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As an important organic fine chemical products, stearic acid, lauryl alcohol esters with high economic value, can be used as fungicides, cosmetics, plasticizers, plant growth regulating agents, the automotive cylinder lubricants, fibers, lubricants, Widely used in light industry, chemical industry, metallurgy, medicine and other industries. The basic literature synthesis of stearic acid lauryl alcohol ester strong acid as catalyst, toluene, and other organic compounds as solvent, 120 ℃ reaction, will inevitably bring about severe pollution and low yield. Enzymatic synthesis of higher fatty alcohol esters have a mild reaction conditions, good selectivity, high yield, in line with the characteristics of green chemistry and environment friendly chemical. Enzymatic synthesis of stearic acid, lauryl alcohol esters literature not reported. This article is based on the above context, exploration of of lauryl best preparation conditions by enzymatic synthesis of stearic acid, and strive to further explain the laws of Enzymatic production of high-carbon ester, and strive to achieve the accumulation of industrial production data. From animal pig pancreatic lipase from the fungus Candida enzyme hydrolytic activity and synthetic activity of research and found that the highest hydrolytic activity of Candida enzyme powder contained Candida enzymes, textile fabrics immobilized membrane highest synthesis vitality. The film uploaded Candida yeast enzymes stearic acid lauryl alcohol ester synthesis study found that this enzyme catalytic esterification of long-chain fatty acids and higher fatty alcohol capacity which can be used in different polar solvents broad pH range of applications, and the moisture content of less demanding, has a higher temperature resistance and other characteristics. The optimum reaction conditions: n-hexane as a solvent, 40 ° C, lauryl alcohol and stearic acid ratio 1:1, pH value 7.0, the amount of enzyme 4% zeolite 0.7 g stearic acid conversion rate of reaction for 4 hours to reach 92.15%. Film carrier enzyme-catalyzed synthesis of stearate, lauryl alcohol esters kinetic mechanism for further study and found that within a certain temperature range, the Arrhenius equation, and by measuring the initial rate of the reaction at different temperatures, the parameter fitting, to calculate the apparent activation energy Ea = 7.821kJ/mol. Through the determination of the initial reaction rate under different substrate concentration, reaction in line with the ping-pong mechanism envisaged bisubstrate enzyme-catalyzed esterification reaction model, application of kinetic equations of the reaction mechanism was discussed, projected the kinetic parameters of the reaction.
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