D
Workshop Summary

EDUCATION

In the first item on the agenda, participants debated the value of green chemistry on the curriculum of the future and spoke about the challenges of rooting sustainability in both the curriculum and textbooks. The need to educate faculty, industrial scientists, and the general public was also discussed. As an introductory comment, Andrea Larson stated that the challenge lay in approaching education at all levels and emphasized the difficulty in understanding the scope and scale of the challenges facing the chemistry community.

Brad Allenby described education in sustainable chemistry within the larger context of the overall changes taking place in this field. Chemistry is shifting in meaning right now, he said. “We appear to be in the period of fundamental redefinition of much of the intellectual landscape, and I think that is important to bear in mind when we think about what we know and what we don’t know,” Allenby said.

Allenby believes the current education system fails to equip any student for the world in which they will be working and living. In particular, the topics of ethics and systems complexity are either missing or severely de-emphasized. In his opinion, no student should be permitted to graduate from any institution of higher learning without completing a course that equips him or her to think about complexity. This should not be a technical course that teaches modeling; instead, it should be designed to teach them how to intuitively consider complex systems and the limitations when working with them.



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Sustainability in the Chemical Industry: Grand Challenges and Research Needs D Workshop Summary EDUCATION In the first item on the agenda, participants debated the value of green chemistry on the curriculum of the future and spoke about the challenges of rooting sustainability in both the curriculum and textbooks. The need to educate faculty, industrial scientists, and the general public was also discussed. As an introductory comment, Andrea Larson stated that the challenge lay in approaching education at all levels and emphasized the difficulty in understanding the scope and scale of the challenges facing the chemistry community. Brad Allenby described education in sustainable chemistry within the larger context of the overall changes taking place in this field. Chemistry is shifting in meaning right now, he said. “We appear to be in the period of fundamental redefinition of much of the intellectual landscape, and I think that is important to bear in mind when we think about what we know and what we don’t know,” Allenby said. Allenby believes the current education system fails to equip any student for the world in which they will be working and living. In particular, the topics of ethics and systems complexity are either missing or severely de-emphasized. In his opinion, no student should be permitted to graduate from any institution of higher learning without completing a course that equips him or her to think about complexity. This should not be a technical course that teaches modeling; instead, it should be designed to teach them how to intuitively consider complex systems and the limitations when working with them.

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs Many American students also obtain the best education in terms of the specifics of their disciplines. However, education at all levels currently lacks conceptual insight in sustainability and green chemistry. The curricula, teaching materials, and emphasis on multi-disciplinary programs that cover not only technical competence but also the social and environmental dimensions of green chemistry are missing. Allenby stressed that there is a need for the ability to understand large-scale systems at an appropriate scale, especially since this is not something that an individual scientist or firm will do effectively. “We need an institutional basis to maintain a dialogue with these systems so that, for example, when the atmosphere begins to display strange chemistry based on a very, very small percentage of CFCs, we are able to respond,” Allenby said. There is also a need for an appropriate prioritization of values, ethics, and goals. Opinions differ on the values placed upon different aspects of green chemistry. “If I am working in a factory and you find a way to substitute for a carcinogen that I am being exposed to, then I am going to like that. I may not care too much if that has impacts down the line on ecosystems,” Allenby explained. These problems are currently being solved on an individual scale. The policy structure at the moment encourages the imposition of individual values, an adversarial process. A single set of values applied to difficult questions will most likely be inadequate, which the field of chemistry needs to move beyond. To achieve this, institutional capability must exist. However, Allenby warned that there might not be any easy solutions. “I think that we need to appreciate the complexity of what we are doing and begin to develop tools that allow us to do better in the short run, while we are working on evolving the institutions we need in the longer run,” he said. Mary Kirchhoff of the American Chemical Society (ACS) looked at some trends in green chemistry education. The ACS Green Chemistry Institute is a strong advocate for green chemistry education. Other voices are also joining this call, which helps to build the case for increased education in this area. “Right now, there are a few champions who are very passionate about what they are doing, believe very strongly in green chemistry, but it is not across the board, and that is really where we have to keep working,” she said. Schools with green chemistry courses include Carnegie Mellon University, Davidson College (North Carolina), and Hendrix College. “You are not limited by the size of your institution, if you want to integrate green chemistry into the curriculum,” Kirchoff said. The green chemistry lab at the University of Oregon offers the most comprehensive approach she has seen. All undergraduates who take organic chemistry are exposed to a green chemistry approach in the lab. The University of Massachusetts has instituted a Ph.D. program in green chemistry. At the University of

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs Scranton, Michael Cann has developed a number of online modules that are easily accessible for use in different categories, such as in physical chemistry, general chemistry, and organic chemistry. However, sustainability education must move beyond four-year-colleges. For example, community colleges tend to be overlooked in the educational picture. In a critical move, the University of Oregon has partnered with the local community college to encourage transfers from two-year to four-year colleges. When these students move to the four-year schools, educators want them to have been exposed to green chemistry and sustainability concepts. Educational textbooks are also devoid of green chemistry, sustainability, or many of the related topics. General Chemistry, Brown and LeMay’s most recent edition, contains five pages on green chemistry within its “chemistry and the environment” chapter. Zumdahl1 has a sidebar on green chemistry that describes the use of CO2 for dry cleaning. Kirchoff said that these are steps in the right direction, but educators tend to skip sidebars in an effort to get through an overly ambitious syllabus. Many interesting topics, especially the more modern research areas, tend to be in sidebars and side boxes. As a result, they do not get covered in the main body of the course. However, Organic Chemistry is very encouraging; Solomon’s most recent edition has five different green chemistry examples embedded in the text. Overall, green chemistry is starting to creep into mainstream textbooks. “This is where I think we really need to be focusing our efforts, if we want to see a lot of students impacted by green chemistry,” Kirchhoff said. In addition, the subjects of toxicity and toxicology should receive more appropriate attention. Usually, the LD50—the “lethal dose” that kills 50 percent of a group of test animals exposed to a material—is the only toxicity or toxicology topic covered. Occasionally, the textbook will refer to poisons and cover the alkaloids and poison dart frogs. There is room for improvement to incorporate these subjects into educational material. Lab lectures should also incorporate more information on sustainability. Even in her own teaching experiences, Kirchhoff only provides technical information about chemicals, such as whether a chemical is hazardous or toxic, when to use it in a hood, or where MSDS sheets are located if students want to look at them. “We don’t have a culture of emphasizing green chemistry topics or related topics like toxicology,” she said. 1   Zumdahl, Steven S. 2003. Introductory Chemistry: A Foundation, Fifth Edition. Houghton-Mifflin.

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs In addition to the lack of educational materials and the over-crowded chemistry education curriculum, the perceived lack of rigor of green chemistry and sustainability is another barrier. It is challenging to conduct and teach green chemistry, because the easy reactions, which involve the use of hazardous materials at high temperatures and pressures, have already been identified. Inertia is also another challenge. Today’s educators have not been trained in green chemistry; it was not part of the curriculum when many of today’s working chemists and chemical engineers were in undergraduate and graduate school. It is a challenge to get over this mind set. What, then, are the available resources? Paul Anastas and John Warner came out with their pivotal work, Theory and Practice, in 1998. Since then, other green chemistry texts have emerged. Even though Doxsee and Hutchison’s lab manual2 focuses on the organic lab, the information is widely applicable to green chemistry in general, and it forms more than just a simple collection of experiments. About a year ago, the Journal of Chemical Education began running a regular feature about topics in green chemistry. One can find lab experiments and different activities regarding green chemistry that can be integrated into the curriculum. In addition, Kirchoff praised the environmental chemistry text by Colin Baird and Mike Cann.3 It provides a breakthrough in terms of integrating green chemistry into mainstream textbooks. A number of different ACS resources also exist. Introduction to Green Chemistry is specifically designed for high school students and is the most popular of the green chemistry materials that ACS has. Students at the high school level and teachers appear to be very interested in this topic. In terms of general public outreach, ACS’ Outreach video provides a good introduction of green chemistry. This informational video focuses on the work of three Presidential Green Chemistry Challenge award winners in a way that is accessible and understandable. Kirchhoff and other speakers noted that chemistry should be considered in the broader context of societal issues. Beyond the Molecular Frontier,4 a National Academies report, specifically emphasized the need for scientists and engineers to understand societal implications in order to enhance stewardship of the planet and recommended a greater emphasis 2   Doxsee, K. M., J. E. Hutchison. 2004. Green Organic Chemistry: Strategies, Tools and Laboratory Experiments, First Edition. Brooks/Cole. 244. 3   Baird, C., M. Cann. 2004. Environmental Chemistry, Third Edition. WH. Freeman. 4   Beyond the Molecular Frontier. 2003. Washington, D.C.: The National Academies Press.

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs on the human aspect of the scientific endeavor. ACS also has an ongoing project called Exploring the Molecular Vision, an initiative by the Society Committee on Education division to examine the reform of chemical education. Project participants have cited the need for emphasizing toxicity education, highlighting the role of chemistry in supporting the environment, and promoting high ethical standards in environmental performance. Green chemistry, sustainability, ethics, toxicology, and safety issues are generally absent from the chemistry curriculum at this point. ACS recommends that green chemistry be taught at the high school, undergraduate, and graduate levels in terms of classroom lectures and laboratory training. The Committee on Professional Training (CPT) also stresses interdisciplinary work. CPT guidelines currently emphasize subjects such as economics, marketing, and business within an environmental context, generally pointing out connections between science and society. CPT also has an environmental chemistry option in which the ACS Committee on Environmental Improvement has recommended that green chemistry should be included. Kirchhoff described different approaches for integrating green chemistry into existing courses and curricula. One method is to develop a whole new course around green chemistry, which has the advantage providing great depth into the subject. The disadvantage is that a new course is usually treated as an elective and therefore does not impact as many people as a required course does. Nevertheless, it is still an excellent way to introduce students to the real “nuts and bolts” of green chemistry. Another route is to integrate green chemistry into existing courses both within the classroom and the laboratory. This can be tricky, especially if educators use textbooks that do not include green chemistry, which requires them to be creative with introducing the subject into their courses. Students should also be encouraged to explore green chemistry on their own. Kirchhoff suggested that, as an alternative to teaching research students the use of established methods, have them instead look in the literature for “greener” tools. There should be an over-arching philosophy of “what are you producing when you do this reaction, what are the by-products,” Kirchhoff said. Educators should consider this even as they teach organic chemistry. Many textbooks do not include the by-products. “There are by-products, and those by-products have consequences,” she said. Conferences, symposia, and school activities provide great opportunity to educate students more about this subject. For example, ACS is organizing their third summer school on green chemistry for graduate students and postdoctoral researchers to be held at McGill University at Montreal in July. The ACS student affiliates program also recognizes green chemistry chapters at schools. Another often-overlooked opportu-

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs nity is the incorporation of sustainability into campus building construction and landscaping. St. Olaf College not only received $500,000 from the Keck Foundation to integrate green chemistry into their curriculum, but they also were awarded $98,000 from the Kresge Foundation for the design of an environmentally friendly science center. “In the end, what you ideally want is a building that is green, with a program that is green. Tie these two together,” Kirchhoff said. There are several benefits in the incorporation of green chemistry into the education curriculum. One is professional preparation; as industry moves toward an increased emphasis on sustainability, they will need students who are trained in green chemistry and sustainability issues. Students themselves have an interest in environmental issues and in demonstrating that chemistry and environmental stewardship are not mutually exclusive. On a practical level, sustainability and green chemistry education can increase lab safety and decrease lab waste. In terms of continuing education opportunities, summer workshops such as the program at the University of Oregon may help faculty members feel comfortable with introducing these topics into their teaching. Many faculty members are uncomfortable because they lack the background in sustainability or green chemistry education and practice. However, continuing education programs may enable them to teach and practice sustainability on their own campuses. Industrial chemists may need similar workshops. Many chemists who currently work in industry also do not have training in green chemistry or sustainability, so they also need to enhance their skills. One participant pointed out that it might also be important to educate patients and doctors concerning the metabolism of drugs. There is a question of how to educate people to take 100 milligrams of a cox-2 inhibitor, instead of pressing for 400 milligrams, he said. Mary Kirchhoff emphasized that it is important to hold students’ interest in green chemistry as early as possible, and to show them that that chemistry is not the grand polluter of the planet but instead offers solutions to some of the environmental challenges that we face. DEFINITION OF GREEN CHEMISTRY One of the recurrent themes was the search for a term for sustainable chemistry, and discussion about the use of the label “green chemistry” or “environmental chemistry” and its definition. Some participants thought the term “green chemistry” did not do justice to the multidisciplinary and integrative nature of the projects they are working on. Some asked if the name green chemistry is not a detriment to what they are trying to achieve. Mary Kirchhoff said it might be a ques-

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs tion of moving “away from the model that, here is chemistry and here is everybody else.” She said there is a need to see that chemistry does not operate in a vacuum, especially at the industrial level. There was also the question that the label green sometimes doesn’t just mean biologically derived; in fact, it means “stop and think about whether it really is better all the way through the life cycle.” Mary Kirchhoff pointed out that the term biologically derived is not so much of the confusion as is the term environmental chemistry. She said when she sometimes receives applications to review green chemistry chapters, many of them have included monitoring the pH in a local stream or cleaning up trash as green chemistry activities. “So, they are sort of confusing care of the environment with green chemistry,” Kirchhoff said. Lauren Heine said it was a great challenge to define what is green. There is no green chemical, she pointed out. “Water, of course, you can drown in it,” she pointed out. But everything is context based, and the material and the metabolism in which it flows have to be considered, she said. According to Heine, the lack of agreement on what defines a sustainable product or sustainable chemistry makes it hard for companies to market a new product. People are often averse to taking a chance in designing a green material, if they don’t know that that definition is going to hold up in the market place. “Because if somebody comes out with a different definition, they may well have invested in a green product that is not perceived of as green,” she said. Heine pointed out that companies should not focus on developing just one or two green chemical products, because it does not demonstrate real commitment to customers, and it does not educate customers. It increases vulnerability at the corporate level if companies only make green that which is profitable. But if a company commits to a corporate-wide strategy of green chemistry, the company will be respected. One participant said the environmental performance and life cycle costs should not be put into an MSDS sheet, because an MSDS sheet is more regulatory and compliance based, that green chemistry deserves its own sheet. Berkeley Cue said green chemistry is the definition he is most comfortable with. It is the utilization of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture, and application of chemical products. He added that many people think green chemistry is just about organic chemistry. Analytical chemistry, physical chemistry, inorganic chemistry, biochemistry, all of the disciplines that interface with chemical synthesis are covered by this definition, Cue said. He reminded the participants of the 12 principles of green chemistry

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs as articulated by Paul Anastas and John Warner, the most important being prevention. “It is better to prevent waste than to have to deal with it once you have produced it,” Cue said. He listed atom economy, less hazardous chemical synthesis, safer chemicals, design for energy efficiency, renewable feedstocks, catalysis, and finally, design for degradation. From the pharmaceutical industry perspective, this is the biggest challenge. The challenge is for the molecules to be stable when they are synthesized, stored, and incorporated in the dosage form. They then should have at least a two-year shelf life where there is no appreciable degradation. They should be stable in the patient when they ingest them, because the active drug has to get to the site of action. Then, as the drug leaves the patient through the biological processes, it would be ideal to have them completely degrade into innocuous materials. There is also a series of 12 green engineering principles that go along with the green chemistry principles. Material and energy inputs and outputs are as inherently non-hazardous as possible. Processes and systems designed to maximize energy, space, mass, and time efficiency, embedded atrophy and complexity, should be viewed as an investment when making design choices. We should target durability and not immortality. Design for all unnecessary capacity capability, one-size-fits-all solutions should be considered a design flaw. Brad Allenby used CFCs (chlorofluorocarbons) as an example to show how the understanding of what is green has changed. CFCs are a classic example of green chemistry because they substituted for fairly toxic, dangerous materials. “If I apply any of the metrics, the heuristics that we tend to use in green chemistry—lower toxicity, lower impact on workers, safer for users, more stable—I would love CFCs,” Allenby said. What made CFCs desirable on one scale—their stability—made them undesirable when they got up into the upper atmosphere and began to break up the ozone. He also pointed out that this happened on a very small scale. “If you were looking at volumetric chemical consumption in the United States, you would not have looked at CFCs,” he said. They were a minor trace atmosphere and yet, because of the dynamics of the system, they turned out to be extremely critical. “So, a green chemical de-stabilized major earth systems with effects that we are probably not entirely familiar with at this point,” he said. CFCs show us that at the time, we did not have the ability to know how to think about what was or was not green, Allenby explained. This means there are gaps in the way that chemistry and its impact on global systems is thought about. But Allenby also said the response to CFCs was positive; alternatives were found, and used where CFCs had been employed, in the electronic sector, cleaning circuit boards, cleaning piece parts. This means the other lesson from CFCs is not to go into paralysis

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs mode just because a green chemical may be potentially harmful some years down the line. Another example is to reflect on green chemistry network components, Allenby said. None of these products exist by themselves. They all tend to be used in a particular context, a network structure, especially something like a telephone. “If you just have a telephone and there are no towers and nobody else has a telephone, then you have got a really kind of interesting paperweight and that is it,” Allenby said. The technology of designing a telephone and designing the way different components and materials work in a telephone is very complex. One of the mistakes that is made in policy, teaching, and thinking is that there seem to be things that are so bad a ban is immediately needed. There are some cases where that has worked well; lead in gasoline is a classic example. Allenby recounted moving to corporate intranets at AT&T. This significantly reduced the material demand of the company in terms of paper. But corporate intranets also add to the value of the whole set of material-based products, like telephones with lead in them. “Is that good or bad? Is that green or is that not green? I don’t know,” Allenby argued. Part of that is the refusal to understand that green chemistry does not operate at the scale of the bench or at the scale of the reaction. It operates at the scale of regional and global systems. “To me, that is an irreducible responsibility of green chemistry and it is one that so far, I think, has not been adequately addressed,” Allenby pointed out. Allenby said green—not environmental science, but green—is a fairly normative kind of concept. Green chemistry injects the normative into the heart of what has traditionally been a physical science. He reminded the audience of C.P. Snow and his theory of social science versus physical science, which are thrown together in green chemistry. “It is a very, very interesting sociological phenomenon, which is not what I think green chemistry intends to be, but I think it clearly is,” Allenby said. He went on to point out that given the scale of human activities, scientists are actually doing earth systems design and engineering. He gave pharmaceuticals as an example. A pharmaceutical is designed to have a specific impact in a specific human system but, at the scale at which any successful pharmaceutical is used, through any metabolic processes that result in products that are released into aqueous systems, it is also designing aqueous systems in developed countries. Data from a number of different fields shows this link clearly, although it is not clear from the way pharmaceuticals are thought about, or regulated and taught. “Unless we understand that something that is designed at bench scale will, in fact, in many cases, impact systems at regional and global scale, we have not yet begun to grapple with what is

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs already occurring in our world; not what is going to occur, what is already occurring,” Allenby said Allenby said it is important to learn to how to pay more attention to scale, to know that metabolic products are going to end up widely dispersed in the environment. “We should ask if we should be designing not just the pharmaceutical, but also the metabolic product,” he stressed. Earth systems engineering and management is where the serious business of green chemistry begins, and it is an area that hasn’t really been focused on enough at all. “Where is our sense of responsibility? That doesn’t mean simply retreating to ideological structures. Ethics and values need to be comprehensive. We need to learn how to dialogue with these systems, and we need to develop the institutional capability,” he said. Green chemistry is classic white space, it imports a lot of concepts from social science and in particular, historically contingent viewpoints into the practice of chemistry, which is very much a white space practice. Unfortunately, Allenby said, we are not really good at dealing with white spaces. A strongly disciplinary scientist or engineer, will tend to view white space work as being fluffy, and an admission by the person doing it that they couldn’t handle the discipline. It is awfully hard to get interdisciplinary work funded. The staff at the NSF tends to appreciate the importance of interdisciplinary work, but the peer review committee thinks a multidisciplinary researcher is a complete flake, and the process breaks down. DEMAND AND PRODUCT DESIGN Lauren Heine gave the participants some background on GreenBlue, and cradle-to-cradle design. She talked about some of the drivers and obstacles for green chemistry, product formulation, and gave some examples of projects that are designed to facilitate adoption of green chemistry. Lauren Heine talked about the furniture flame retardency partnership and the Design for Environment (DfE) Green Formulation Initiative for cleaning products. She also gave an example of a company using green chemistry as a strategy for product development. The furniture flame retardency partnership was an EPA project, part of the DfE program. GreenBlue is about a year and a half old. It is a not-for-profit organization in Charlottesville, Virginia, that was founded by William McDonough, a well-known green architect, and the German chemist Michael Braungart. They wrote a book called Cradle to Cradle: Remaking the Way We Make Things. The book argues that industry and the public can use the following design principles: using current solar income, celebrating diversity of people, products, geographies, cultures, needs, and design, and that waste equals food. The waste equals food theme is very

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs powerful, Heine explained, as biological materials can be perceived of as nutrients, flowing within biological metabolisms, and technical materials such as metals or polymers can be perceived of as technical nutrients, flowing in technical metabolisms. The value of these materials gives rise to the thought of designing an entire system, and a biological metabolism may be the environment in the broader sense or it also may be a wastewater treatment plant. There has to be thought about designing the biological material, so that it can be metabolized. Sometimes the focus is on designing materials for existing metabolism, and sometimes on designing metabolisms for materials. In the application of these ideas, the first step is to analyze the chemical composition of materials used, to select materials based on safety to humans and ecological systems, and then to design these materials to be nutrients, for high-value recovery or other beneficial uses. Energy recovery could be considered one of the recoverable values, Heine argued. Heine talked about the cradle-to-cradle model. There is value in a big picture mental model, like cradle-to-cradle design, she said. While it initially may sound hokey to an engineer, it is powerful because it engages technical and non-technical people alike. Secondly, it provides a vision, but not a prescriptive approach. Thirdly, the focus on materials and metabolisms points to the importance of systems, and collaboration with others within the value change. GreenBlue sees this as a short-term strategy to move companies and organizations toward sustainability. How well the strategies will work 10 or 20 years from now is not clear, as there may be more important strategies to take. Heine then named some of the obstacles to integrating green chemistry into product formulation. First, change is always difficult, she said. There are huge manufacturing and market challenges. There is a big customer disconnect. Manufacturers will say, we have the brain power, we can make anything, but our customers are not asking for green materials. They might say, we make green chemistries, but our customers aren’t buying them. There is a big disconnect there. A lot of human and ecological toxicology and life cycle impact data is missing that could support decision making. There is a lot of data out there, but it is not necessarily in a form that can support decisions. Two examples are material safety data sheets (MSDS) and technical fact sheets. People look to these to help support decision making, but they are not always very useful. Heine showed an MSDS for a green product that did not show any ingredients. MSDS’s are often wrong, they are generally incomplete, and there is no standard format for them. There is an American National Standards Institute (ANSI) format that is a very good format, that includes environmental attributes, but there are no require-

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs additional chemical and mechanical treatments to remove the remaining starch in it and obtain the desired “look.” Historically, oxidizing agents or sodium hydroxide pressure-cooking were needed to get rid of the starch. Now, amylases are added. Cellulases in laundry machines replace the pumice stone that was originally used to make stone washed jeans. The bleaching process now operates with lactase instead of chlorine and other bleaching agents. To demonstrate that the environmental burden of making the enzyme is outweighed by its sustainable applications, Novazyme performed a cradle-to-grave life cycle analysis. For the analysis, the company compares two systems: a combination enzymatic/chemical system and an enzyme-only system. Scalazyme, a pectin ligase enzyme that breaks up pectin in cotton, was presented as an example for the life cycle analyses. It was incorporated into the entire process from cotton processing to knitting. First, a scouring step is required to bleach the cotton and prepare it for coloring, a process which normally requires sodium hydroxide, acetic acid, surfactants, energy, and voluminous amounts of water. Novazyme examined this step and found that the scalazyme enzyme could provide a tremendous reduction in the amount of resources that are used in the original process. With the enzymes, the energy demand is reduced by 25 percent, resource consumption is decreased by more than 25 percent, and water use is cut by 65 percent. If the process by which all cotton in Europe is scoured could be converted to this scalazyme process, it could prevent the pollution of enough water to supply 400,000 people. In 2001, Novazyme won a Presidential Green Chemistry Award for the process. Another example for waste reduction is phytase, an enzyme that breaks up phytic acid in plant material. It can be used to replace the addition of inorganic phosphate to animal feed. Animals fed from phytase-treated feed need less inorganic phosphate in their diet, which results in less phosphate released to the environment. A significant reduction in nutrient salt pollution is also seen. If 23 million pigs in Denmark were given phytase-treated feed, the estimated reduction of aquatic phosphate pollution would be enough to supply an additional amount of potable water for 300,000 people. Another example is amylase in baking, which is used for extended shelf life of bread. Bread treated with amylase has a modified structure of starch such that it doesn’t recrystallize, effectively preventing the bread from going stale. This reduces waste in terms of transportation and wheat production for the supply of bread. “If this was used in all the white bread in the United States, you would probably save the CO2 effects of 50,000 people,” Nedwin said. A future use of enzymes could be in the production of bioethanol, which is made from corn starch, and the challenge is to make it this way

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs as economically as possible. Bioethanol is sustainable and is an almost CO2-neutral energy source. It can replace MTBE as an opting booster in gas. Ten states have successfully banned MTBE, which creates a 1.4 billion gallon per year market right now. Fuel ethanol as a fluid energy source for the transportation sector is the only alternative to gas, except for biodiesel and gas. Today there are blends of 10 percent ethanol, and 20 percent ethanol biofuel is used in Minnesota. In the year 2000 alone, it is estimated that the ethanol industry added 22,000 new jobs and more than $15.3 billion to the gross output of the American economy. Replacement of all MTBE used in gasoline comprises about six percent of total gasoline substitutions, which amounts to a need for 10 billion gallons of ethanol a year. The current corn ethanol production is about three billion gallons a year, an amount that can only provide ethanol gasoline substitution for 30 percent of all gas in the United States. Furthermore, the total MTBE replacement would consume about 30 percent of the farm land growing corn. These facts prompted the Department of Energy to fund a very significant research project with Novazyme and Genencor to evaluate alternatives, operating on a budget of about $18 million over four years. Corn is currently broken down by amylases to corn starch and glucose. The alternative to corn-derived cellulose material is the use of corn stover, which consists mainly of cellulose and hemicellulose. NREL worked out an acid pretreatment process for corn stover, which delivers 56 percent cellulose. The cellulose is further broken down by using a mixture of cellulases. Unfortunately, the corn stover/cellulase process is 50 to 100 times more expensive than the corn/amylase route. There are several different ways of making enzymes less expensive, Nedwin said. These include reducing enzyme production costs by reducing the cost of feedstocks and enzyme recovery processes, by employing onsite production of enzymes where the corn is grown, by increasing the fermentation yield, or by increasing enzyme activity on a program basis. All factors point to novel enzymes that can be genetically engineered to be tailor-made to specific industrial processes. Enzyme candidates can be integrated into an expression host, characterized biochemically, and tested on the conversion of pretreated corn stover to ethanol. The enzyme cost to make a gallon of ethanol from corn starch is between five and ten cents. The enzyme cost from biomass was $5.40 at the onset of this project, and it is now down to 27 cents,6 which is a 20-fold reduction. The ultimate goal in order to compete with cornstarch is about 10 cents. For this work, 6   This figure was current at the time of presentation in February 2005. However, at press time, Novozymes announced that the enzyme cost had been lowered to $0.10-0.18 per gallon ethanol, a 30-fold reduction.

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs Novazyme received two awards in 2004, the Scientific American 50 award and, together with NREL and Genencor, an R&D-100 award. Nedwin said pretreated corn stover is about the furthest advancement in terms of technology today. The future needs other pretreatments and mixes of enzymes with different types of substrates. “If we look at making the biorefinery happen in a big way out of biomass, we need government support. If we look here historically, the government has had tremendous help in pushing industry, in the railroads, in the Detroit automotive industry, and even the biotech, by changing patent laws,” he pointed out. Nedwin summarized the role of enzymes in sustainability. Today, only five percent of fine chemical, polymer, bulk chemical, and specialty chemical industries are impacted by enzyme processes or wholesale microorganisms. McKinsey & Company estimated that by 2010 this number can be up to 10 to 20 percent, which translates into sustainable development to produce less pollution using enzymatic routes. He added that knowledge of enzymology in the chemistry industry needs to be broader, as does the awareness of applications and demand. But in the end, enzymes must be price competitive. Participants asked about enzymes in nonaqueous environments, as enzymatic hydrolysis is found only in aqueous environments. Glenn Nedwin said there are some breakthroughs being made in that area, such as lipases which work in organic solvents and immobilization of lipases and other enzymes. MEMBRANE PROCESSES William Koros talked about membranes and separation processes and their energy saving potential. He showed that this technology has great potential with the help of some examples; nevertheless, it is nonetheless still underdeveloped. Separation technology is a possible application to save energy. In the United States, around 33 percent of the total energy use is in the industrial arena, and 40 percent of that fraction is used for separation. This translates into about 15 percent of the total energy use. If this number could be lowered, it would have an enormous impact. This is a huge opportunity, because global capacity will grow over that period of time. If the capacity that is installed today is based on current, largely thermally-driven technology, then membranes will not sustain it as the world stabilizes at a population of 10 billion. “[W]e are buying what we are going to live with in terms of thermal separations if we don’t do something,” Koros said. Membranes have great potential as energy savers, Koros said. Looking across the separation spectrum, membranes are the low energy inten-

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs sity enablers that can allow energy conservation in the chemical industry. In an ideal sense, this technology is not thermally driven, but instead mechanically driven. “So, one avoids a lot of the second law restrictions that are currently plaguing separation processes,” Koros said. But the technology is insufficiently developed. Although membranes have the greatest potential to facilitate low energy processes, they are by far the most immature in terms of technical development. The reason for their lack of application is due to a failure to implement improvements for installation of those membranes. Koros pointed out that membranes could be used in large-scale processes. Many times people are under the mistaken impression that membranes do not scale, Koros said. Other very selective processes like chromatography and affinity methods do not scale very well, but membranes and adsorption do. In fact, membranes and adsorption are a very powerful “one-two punch,” because adsorption can deal with very dilute solutions, while membranes can deal with more concentrated solutions. In many cases, hybrid systems incorporating these two technologies are very attractive. There are two fundamentally different kinds of membranes. One operates primarily on the basis of hydrodynamic sieving, which is not actually a filtration process but rather a more subtle process. The size of the rejected entity ranges from 20 Angstroms up to chunks of dust, and it is very easy to shear away and strip away a suspending medium. Usually it is an aqueous organic suspending medium passing through the membrane, and in which some undesirable component is rejected. Something very different happens when the scale of what is being stripped is on the same order of magnitude as the medium from which it is being stripped. Separation of an aqueous suspending medium with salts or organic components is very energy intensive to separate. In a process called ultrafiltration (or microfiltration), a physical pore is built into a membrane in order to separate particles that are less than 20 Angstroms in diameter. A transmembrane pressure drives the suspending fluid via current flow through the membrane, while the rejected biomolecule is separated because it can’t fit through the pores. This technology is a very powerful energy saver. As calculated by Koros, capturing a cubic meter of water using this technology costs about 6.7 kilowatt hours per cubic meter (assuming 33 percent energy efficiency) compared to about 73 kilowatt hours per cubic meter using an optimized, fairly efficient triple effect type evaporator method. The real cost, in terms of mechanical energy, is about 2.2 kilowatt hours per cubic meter. The problems of this process boil down to the need to obtain better control of pore size and uniformity. If the process involves larger solids or more complicated feeds, such as renewable feedstocks, it becomes very

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs important to control the physical chemistry at the membrane surface. If one takes a step into the next part of that spectrum and considers stripping away micromolecules from micromolecules, or ions from water, it becomes an extremely expensive and energy intensive proposition. Water must want to be in the membrane more favorably than does the ion or the organic molecule being rejected. In addition, once it is in the membrane, there has to be more favorable molecular diffusion process to cause that separation. While this technology exists as a functional one, it is only known to work well for aqueous systems in a highly evolved state, Koros pointed out. Seawater reverse osmosis is the only well developed example. This is very compatible with wind generation, because it could be off-shore and wind could drive the pump to bypass some of the second law restrictions regarding thermal generation of energy. The energy cost is about 10 times more efficient than that for the thermal option. This could have implications on a worldwide basis. Around the globe, there are about a billion people who do not have adequate drinking water. About nine billion gallons of water are desalinated every day around the globe, half of which performed thermally in plants that were constructed before membrane technology existed. Due to investment in research, most of the new de-salination plants are now membrane-based. The savings could be about 1.4 quads a year, Koros calculated, which is essentially a payback on the roughly $1 billion of research that was invested in the membrane option over the last 40 years. There is a whole array of other kinds of membrane applications such as olefin paraffin separations which remove sulfur and benzene from gasoline or isomer separations that distinguish between normal and more bulky isomers. These kinds of separations can be performed but not very well with the current generation of membranes. To have an impact on the energy use, they would have to be as efficient as a reverse osmosis unit. Koros looked at another example of separation: propane and propylene, a significant market of about 25 billion pounds a year with a growth potential on par with the GDP. Currently, it is a very expensive and energy intensive process conducted through cryogenic distillation. A new unit costs about $50 million, but membranes could cut both energy costs and the capital costs, Koros said. The problem is whether such a membrane actually exists. Propane and propylene are very similar; propylene has a compact and a bulky end, but propane only has a bulky end. The difference in size is about half an Angstrom. “If you simply take a polymer and turn it into a carbon molecular sieve at 500 or 550, all of a sudden, you get an enormous selectivity because it becomes possible to do size and shape discrimination that is simply not possible by a polymer alone,” Koros explained. Tenths of Angstroms can be easily distinguished.

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs However, cost is still a problem. This process is about a thousand times more expensive per square meter of membrane than the polymer process. “I think the only thing that can be done is analogous to walking on both legs. You don’t count on all your left leg or your right leg. Organics or polymers are very easy to process,” Koros explained. Both technologies need to be developed. Inorganic- and carbon-based membranes are extremely selective because of their rigid size and shape discriminating ability. There must be investment into the development of the next generation of membranes that retains this exquisite size and shape separating capability. In some cases, organic polymers do fine, such as in reverse osmosis. However, as there is a need for increasing selectivity, the next generation technology is being pushed almost to a pure inorganic glued together by a polymer. It can be achieved, as early work in the last couple of years has demonstrated. It is possible to put a million of these fibers into a module that is about a foot in diameter and about a meter long with the surface area of a football field. If the hybrid material can be put on the outside of the fiber while maintaining the inside as a flexible material, “it thinks it is a polymer in terms of mechanical properties but, in terms of its separating properties, it thinks it is a molecular sieve, or at least a hybrid material,” Koros said. The idea is to integrate this material into a practical process in which mixtures of molecular sieve entities and polymers are made up as a “dope.” It is spun into a hollow fiber about 200 microns in diameter, placed through fluid exchange, and dried. Instead of a thousand-fold higher cost, the estimate is about $5 a square foot or $50 a square meter. “This technology is about where I would say aqueous reverse osmosis was in the late 1960’s. It was clear that it worked, but it didn’t work very well, and there still has to be a significant investment made. We are making a decision. We are either going to invest in something that has this ability to cause an order of magnitude reduction or we won’t,” Koros said. Participants asked if membranes offer an opportunity to separate a molecule the size of water from a 300-, 400-, or 500-gram per mole pharmaceutical, for example as in a waste water treatment facility. This process would be somewhere between a true solution diffusion process and one that has aspects of a filtration process, Koros said. There are membranes in this dimension, and they are not difficult separations in aqueous systems. Separations for hydrocarbons have the problem that hydrocarbon molecules are dissolved on the surface of the inorganic membrane, one of the participants noted. A major interest is in organic membranes because they withstand very high temperature conditions. There are some thoughts that, by cutting the surface of the membrane material, the ad-

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs sorption factor could be eliminated. Koros replied that membranes are variations of that idea, which are easier to process. Usually, depending on what the hydrocarbon is, it is possible to have the material tight enough that it won’t allow large molecules in. The membrane already does part of the separation, and it acts as a sort of a raincoat for the membrane that is doing the fine separation. “Now, in terms of being able to use a pure inorganic or carbon, I won’t say that that will never happen. I am afraid that what has to be done is, we need to get onto the field with some technology that actually works, so that people don’t invest in these high energy intensive things,” Koros said. GREEN CHEMISTRY FOR CARBON MANAGEMENT Klaus Lackner talked about the challenge of using fossil fuels, a new fuel economy, and how to intelligently and safely dispose of CO2 produced by the world’s population. The situation of fossil fuels is precarious. If 10 billion people—the potential future global population—start consuming energy at the same rate as the United States, Lackner said that CO2 emissions will lead to climate change on an unprecedented scale. He stated that there is a high likelihood that there will be shortages in oil and gas and pointed out that the global population has been faced with the situation of 30 remaining years of reserves for the past 100 years. “The other unfortunate point is [that] all of that oil is concentrated in the Middle East,” Lackner added. He said two problems—climate change and the end to global oil reserves—will become acute at the same time, which will occur some time in the middle of the century. He emphasized that fossil energy is absolutely vital to the economy. “It is about 85 percent of the total, and I have a very hard time seeing that, in the short term, it is going to be replaced,” Lackner said. But the scale of energy consumption is so large that it might be difficult to find alternatives. The three big alternatives are solar energy, nuclear energy, and fossil fuels. Solar energy is not likely to provide a complete substitution anytime soon; only one ten thousandth of the solar energy on earth is being used. Nuclear energy is the other big player. People argue that the uranium reserves might be too limited. However, if the technology were better, it would not be a problem, Lackner said. With current research, there is a decade or two left for the world energy consumption to use fossil fuels. Lackner projected that there will be fossil fuel for the next 100 to 200 years at a price similar to today’s prices. To underscore that point, Lackner recounted South Africa’s situation under embargo, a time when the country still managed to produce gasoline for about $45 a barrel.

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs From a raw resource point of view, Lackner argued there is no guarantee that fossil fuels will run out in this century. Unfortunately, the environmental havoc will be horrendous if the CO2 problem is not resolved. This means that the fossil fuel cycle has to be engineered; products must be benign and safe, either for use, or for ultimate disposal. It also means that fuel has to be produced from all fossil resources, and advances in gas to liquid and solid to liquid transformations must be made to bring prices down. Disposing of the carbon dioxide is a major challenge, Lackner said. Lackner stated his point of view that any chemical returned to the environment should be in its ground state. This requires a thermodynamic transformation from CO2 to an even lower state, the carbonate form. The amount of CO2 in the atmosphere is increasing. In 1800, it held about 550 gigatons of carbon. It is now in the 750 gigaton range. Current consumption of fossil fuels is about 600 gigatons per year, which is equal to the entire standing biomass. But it is not clear if fossil fuel use will increase by three or four times as much in the coming century. Nevertheless, the CO2 output could potentially amount to orders of magnitude that are huge compared to soil and biomass content. It is already large compared to the storage capabilities of the ocean. In other words, there may be 39,000 gigatons of carbon dioxide dissolved into the ocean, but it cannot be removed or added without drastically changing the pH of the ocean. A pH change of 0.3 would be equivalent to roughly 1,200 to 1,400 gigatons of dissolved CO2. Some hypothetical disposal grounds for CO2 are the ocean, biomass, and the soil. If 30 percent of the ocean’s volume were to be acidified, it would cover some fraction of CO2 disposal, and if biomass could be increased by 50 percent, the disposal of carbon in soil could be increased by another 30 percent. None of these options are ecologically acceptable, feasible, or practical with current technology, Lackner said, and that still wouldn’t come close to covering the emissions if business ran its course as usual. Even in a no growth scenario, CO2 will be a huge problem. The last 200 years has produced 300 gigatons of CO2, and there will be another 300 gigatons released before 2050. “So, this, in a nutshell, is the problem. The fossil carbon pie, in some sense, is rather limited,” Lackner said. To cope with these problems, Lackner said all three major energy options had to be left open since current solar capacities could not be counted on as a full replacement strategy. Nuclear energy, on the other hand, is far too complex and too expensive to replace fossil carbon. “We simply cannot abandon in the foreseeable future the one option which currently works, but I don’t want to belittle the problems,” Lackner said. This still requires massive changes. An entirely new energy industry

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs has to be built, and CO2 emissions between now and 2050 must be held constant. It also means the establishment of an energy economy at the current, or double the current, size that will not emit CO2 while simultaneously allowing the current CO2-emitting energy economy to exist. Lackner cautioned against depending on rising efficiency. “If you throw every efficiency and every trick in the book into this game, you might be able to hold things constant until 2050. The problem is, at that point, when the options run out and CO2 levels start rising again naturally, the effect is effectively zero by the end of the century,” Lackner said. This is why there is a need for new technologies to keep CO2 levels constant. CO2 has to be collected and disposed of at the big concentrated sources in a permanent and safe manner. At the same time, CO2 has to be captured from the air in order to deal with the waste produced by the transportation sector. Lackner then discussed the options for disposing of carbon dioxide. One of the proposed routes is storing it in the ocean. Since the oceans will simply acidify, Lackner said that idea has been discredited. Furthermore, the turnover requires an 800-year time scale, which means the greenhouse gas problem is merely postponed to be dealt with by future generations. The second option is to put CO2 under the ground. This is done today, as the United States buries some 20 to 30 million tons of CO2 for the sake of enhanced oil recovery. CO2 can also be pumped on to coal bed methane or into saline aquifers. Most people suggest 300 gigatons of carbon can be stored in these ways. “But by the scale we are looking at, this is not enough,” Lackner pointed out. Furthermore, there needs to be a minimum of 10,000 years in securely storing the carbon. The third possibility could be going to the thermodynamic ground state. Carbonates are in a lower state than carbon dioxide. Carbonic acid dissolves serpentine rocks, and the serpentine reacts, forming silica and magnesium carbonate. It is an exothermic reaction, producing about 63 kilojoules per milliliter and giving free energy points in the right direction, even with ambient CO2. But there are still some drawbacks, Lackner said. While the reaction is spontaneous and will stabilize itself, it takes about 100,000 years to occur. As a result, there is a need for an industrial process to bring the reaction time to under an hour. Claiming the rock and dealing with metallics are both affordable. Reclaiming the mine is also affordable, and all this can be done for less than $10 a ton for CO2, but the reaction is simply not fast enough. Using energy would be self-defeating, but at this point, with a 40 or 50 percent energy panel, it can be done for $100 per ton of CO2. That is a factor of three or four higher than the desired cost of about $30 per ton of CO2, “at which point you add maybe two cents to the kilowatt hour and about 25 cents to the gallon a gas,” Lackner said.

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs There is a need for the right catalyst and the right preprocessing step. Lackner suggested using a weak acid to first dissolve this material, making the magnesium salt, and then switching it to the carbonate to recover the acid. The weaker the acid, the easier it is to recover, but it also corresponds to a smaller reaction rate. Determining how to gain another factor of three to five, perhaps even ten, in this process would make all the difference between success and disaster, Lackner said. From a policy point of view, it is absolutely critical because it signals an open door. “The only one of the methods which… opens the door to the next 100 to 200 years is this dramatic step of forming carbonates,” Lackner stressed. There is plenty of peridotite rock, which contains olivine, serpentine, and magnesium silicates. Oman alone has more serpentine than would be needed to deal with all the carbon reserves in the world, but it is highly distributed all over the world, Lackner said. The obvious place to store CO2 is in power plants, Lackner said, which could also be hydrogen plants. Since hydrogen is likely to come from fossil fuels for a long time. Lackner estimated a price range in gigajoules of energy for various fuels to back this prediction. At a gigajoule, coal on average usually costs less than a dollar. Oil is $6 per gigajoule at $30 per barrel, and electricity, at five cents, is $14 a gigajoule. If hydrogen is to be made from electricity, the cost will be at least $20 a gigajoule for hydrogen. From natural gas or coal at today’s prices, it is $6. The obvious prediction is that hydrogen will be made from the cheapest source—coal. Hydrogen can also be derived from tar, coal, shale, or biomass, but it is very unlikely in the foreseeable future to come from wind, photo well tanks, or nuclear energy. “Unless you put on your burner one cent a third kilowatt hour, which I think is an achievable goal for photo well tanks in the long term, you cannot make hydrogen from it,” Lackner said. Bypassing the CO2 problem by using windmills may not be possible. The energy that feeds the wind is about 20 times the energy the world consumes today. It is not clear how much wind energy can be harvested without having an impact on the wind field and thus perhaps on climate. Furthermore, a windmill would require at least 80 square meters of rotor-swept area in order to supply enough energy for a single person in the United States. In comparison, the CO2 output per person would flow through an opening the size of a television screen. Therefore, a device to capture the CO2 produced per person would be a factor of several hundred times smaller than one to collect wind energy for that same person. With the ability to capture CO2 from the air comes the option of either making hydrogen from fossil fuels and collecting the CO2 at the hydrogen plant or running your cars on gasoline and capturing an amount of CO2 from the air that compensates for the emission. In addition, if renewable energy

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Sustainability in the Chemical Industry: Grand Challenges and Research Needs becomes affordable, it is possible to create synthetic carbon-based fuels from CO2 and H2O by using the energy to reduce carbon and hydrogen. Even hydrogen might not be feasible. If the cost drops to $30 per ton of CO2, hydrogen will still not be competitive because the distribution system for the hydrogen will be very expensive. If hydrogen is piped from a central power plant which collects its own CO2 to destinations across the country, it will cost a lot of money. However, the dream of the hydrogen economy is to close the loop and have a renewable energy source to split water into oxygen and hydrogen, giving hydrogen to the consumer who then recreates water. If CO2 can be captured from the air, the same loop is slightly more complicated. The CO2 and hydrogen can be used to run an old-fashioned fissure trough to make gasoline. This means the ability to capture CO2 may actually open doors for carbon in any of its hydrocarbon forms to become an alternative energy carrier. The world may then no longer need fossil fuels if this alternative energy carrier to hydrogen can be used in a vehicle. The future might hold a spectrum of pure carbon to pure hydrogen and, in that spectrum, there is a fuel of choice that can be oxidized. “At the point where you use it, you make CO2 and water, and you give it back,” Lackner said. In a situation where it is very easy to obtain hydrogen for an application—for example, a city bus in a bus fleet—hydrogen might be preferable. This opens up a whole new chemistry of sorting out what fuels are appropriate for the right circumstances and how many different ones can be supported. New power plants, recovering CO2, and the chemical transformation of CO2 into a stable deposit, will all open doors. But there will have to be an energy revolution in the next 60 years. “If we did what we did the last 50 years, which was essentially doing the same thing slightly better, and incrementally more and more and more of it, we cannot repeat this for another 50 years,” Lackner said.