Scaling-up Synthesis Of Ethoxylated Fatty-acid Methyl Esters

Ethoxylated Fatty-acid Methyl Esters (EFME) with different hydrophobic chains and different EO numbers were synthesized from isolated or mixed fatty-acid methyl esters by direct ethoxylation in the presence of a special catalyst. Their physico-chemical performance was investigated in detail. The experiment results show that EFME has some special characteristics such as higher cmc, lower cloud point and foam self-quenching profile. It is that the capped methyl group in the hydrophilic end of EFME is the most important factor to affect its behaviors. Based upon the above results, this study clarifies the differences between EFME and alcohol ethoxylates (AEO) by comparing surfactant properties of C12-EFME with different EO adduct numbers and C12-AEO. The experiment results also show that the behaviors of EFME can continuously change depending on the EO numbers. EFME has special advantages such as lower price and less foam and is similarly to AEO in the other aspects so that it has the potential to substitute for other ethoxylated nonionic surfactants. Catalyst activity and EO adduct distribution under different catalysts were assessed in the direct ethoxylation of methyl, and a better catalyst composition was screened out.When the catalyst was prepared in the ratio of Al/ Mg= 0.69 under the condition of desiccation temperature 40 ℃, crystal temperature 65-75 ℃, crystal time 18 h and calcinations temperature 500 ℃ the catalyst activity could reach 0.84 gEO/gCat/ min.This kind of catalyst always has high activity capability and can be used repeatly after calcined.EFME that was chemically modified by blocking PO between the capped methyl group and EO chain displays lower foam stability and better rheological properties, which reveals that the new applications of EFME can be developed, for example some product of low bubble even no bubble.Catalyst and EFME were scaled up respectively after success in lab. The best activity of catalyst is 0.73 gEO/gCat/min and the various performance of product EFME are fitted together very much with products synthesized before. Then scaling-up of catalyst and EFME were done respectively. The best catalyst activity is 0.75 gEO/ gCat/ min, and the product EFME has the narrow EO distribution which EO distribution index number is above 70%.The content of no-reacted methyl ester that is 2.85% and by-product PEG that is 3.46% were measured by HPLC.