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From page 62... ... 5-1 SECTION 5 TIER 2 RESULTS Aircraft Type IV Anti-Icing Fluids Table 5-1 lists the FPDs, surfactants, thickeners, and corrosion inhibitors that were selected for evaluation during Tier 2 testing of Type IV aircraft anti-icing formulations. Based on the results of Tier 1 testing, the FPDs that were selected showed improvements in COD, BOD and/or aquatic toxicity over propylene glycol. Read the entire page →
From page 63... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-2 TABLE 5-2. Method of down-selecting thickeners for selection of FPD and thickener with minimum aquatic toxicity and cost. Read the entire page →
From page 64... ... SECTION 5 -- 4BTIER 2 RESULTS 5-3 TABLE 5-5 Method of down-selecting corrosion inhibitors. FPD Thickener + Surfactant Corrosion Inhibitora Down Selectb Aquatic Toxicity DEG A + C TEA Mazon RI 325 E Perform complete aquatic toxicity tests on down-selected mixture (FPD+A+C+E) Read the entire page →
From page 65... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-4 Kelzan HP and K1A96 • Formulation was done with deionized water at room temperature. • A mixer or blender was used to ensure adequate dispersion of the thickener particles. Read the entire page →
From page 66... ... SECTION 5 -- 4BTIER 2 RESULTS 5-5 mixed with water and the viscosities compared to a commercially available Type IV formulation. The change in concentration of the thickeners to match the viscosity of the commercially available Type IV formulation was evaluated for each thickener. Read the entire page →
From page 67... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-6 Figure 5-1. Viscosity of Kelzan HP and K1A96 at different concentrations and shear rates for glycerol/water and diethylene glycol/water mixtures. Read the entire page →
From page 68... ... SECTION 5 -- 4BTIER 2 RESULTS 5-7 Figure 5-2. Viscosity of Carbopol EZ-4 with TEA at different concentrations and shear rates for glycerol/water and diethylene glycol/water mixtures. Read the entire page →
From page 69... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-8 TABLE 5-7. Concentration of thickeners (wt %) Read the entire page →
From page 70... ... SECTION 5 -- 4BTIER 2 RESULTS 5-9 Figure 5-3. Comparison of viscosity/shear rate data for selected thickener concentrations to commercial Type IV formulation. Read the entire page →
From page 71... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-10 Table 5-9 summarizes the aquatic toxicity and cost of the thickeners at the concentrations shown in Table 5-4 (to match the commercial Type IV formulation) Read the entire page →
From page 72... ... SECTION 5 -- 4BTIER 2 RESULTS 5-11 surface, but the measurements were inconsistent. The experimental procedure was revised for determining an advancing contact angle, in which the contact angle is measured while the drop on a surface is increasing in volume. Read the entire page →
From page 73... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-12 Figure 5-4. Surface tension for Si/Au surface using data from Table 5-10. Read the entire page →
From page 74... ... SECTION 5 -- 4BTIER 2 RESULTS 5-13 Figure 5-6. Contact angle measurement results for glycerol/water and surfactants. Read the entire page →
From page 75... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-14 64 has a significantly lower toxicity than the two other surfactants. The LC50 for the rest of the surfactants was close to those of the FPD. Read the entire page →
From page 76... ... SECTION 5 -- 4BTIER 2 RESULTS 5-15 Figure 5-7. Comparison of Viscosity of DEG/ and glycerol/water/thickener (Carbopol EZ-4/TEA formulations with and without the addition of surfactant. Read the entire page →
From page 77... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-16 mixtures. This result suggests that for the DEG/water formulations containing both a thickener and surfactant, the surfactant concentration should be increased to match the contact angle for the commercial Type IV formulation. Read the entire page →
From page 78... ... SECTION 5 -- 4BTIER 2 RESULTS 5-17 Foaming is a potential problem for deicing aircraft because the deicing formulation may cover the windows and impair visibility for the pilot. Foaming tests have been included in AMS 1424H for SAE Type I deicing/anti-icing fluids but have not been included in the requirements for Type IV anti-icing fluids. Read the entire page →
From page 79... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-18 Ridafoam, an anti-foaming agent, was placed in the two formulations containing Carbopol EZ-4/TEA and Tergitol L-64 at 10 percent of the surfactant concentration (Table 5-12) Read the entire page →
From page 80... ... SECTION 5 -- 4BTIER 2 RESULTS 5-19 freezing point) , it is likely that the solution will not form an actual slurry but just a highly viscous solution. Read the entire page →
From page 81... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-20 FPDs/Water, Thickeners, Surfactants, and Corrosion Inhibitors Corrosion tests using sandwich and total immersion were conducted with the two most promising DEG formulations shown in Table 5-14 according to the specifications in SAE AMS 1428 Type IV Fluid. Sandwich corrosion testing was conducted in accordance with ASTM F 1110, Standard Test Method for Sandwich Corrosion Test. Read the entire page →
From page 82... ... SECTION 5 -- 4BTIER 2 RESULTS 5-21 Total immersion testing was carried out in accordance with ASTM F 483, Standard Test Method for Total Immersion Corrosion Test for Aircraft Maintenance Chemicals. The method involves immersing three test coupons of the same alloy in concentrated and diluted anti-icing solutions for 168 hours at an oven test temperature of 38°C. Read the entire page →
From page 83... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-22 replicated 10 times with one C dubia or two fish per replicate. Read the entire page →
From page 84... ... SECTION 5 -- 4BTIER 2 RESULTS 5-23 TABLE 5-17. Comparison of theoretical values with measured test results for step-wise Type IV anti-icer formulation construction Added Component Percent of Mixture Theoretical Values Test Results Microtox® EC50a (mg/L) Read the entire page →
From page 85... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-24 of the acute toxicity endpoints in the final DEG formulation in this research was 32,700 mg/L in the final DEG formulation. Chronic toxicity endpoints ranged from 79.4 to 1,350 mg/L in tests with current-use formulations with each of the four tested products having one or more of the three endpoints at least as low as 130 mg/L (1) Read the entire page →
From page 86... ... SECTION 5 -- 4BTIER 2 RESULTS 5-25 too little or too much to determine reliable BOD5 concentrations. Results from the BOD28 tests indicated that the microorganism population eventually acclimated to DEG with accelerated biodegradation occurring approximately halfway through the 28-day test period. Read the entire page →
From page 87... ... ALTERNATIVE AIRCRAFT ANTI-ICING FORMULATIONS 5-26 additives were fine powder and passed through the smallest sieve (2.38 millimeters) Read the entire page →
From page 88... ... SECTION 5 -- 4BTIER 2 RESULTS 5-27 aRelative to individual component. Further experiments with sodium formate and mixtures of sodium formate and tripotassium citrate were continued. Read the entire page →

From page 62...

... 5-1 SECTION 5 TIER 2 RESULTS Aircraft Type IV Anti-Icing Fluids Table 5-1 lists the FPDs, surfactants, thickeners, and corrosion inhibitors that were selected for evaluation during Tier 2 testing of Type IV aircraft anti-icing formulations. Based on the results of Tier 1 testing, the FPDs that were selected showed improvements in COD, BOD and/or aquatic toxicity over propylene glycol.