The Study Of Ethoxylation Catalyzed By Mg-Al Complex Mental Oxides And Enzymes

Two new applied nonionic surfacants(fatty alcohol ethoxylates of the narrow range and fatty acid methyl ester ethoxylates) were studied. Mg-Al hydrotalcite-like compounds was synthsized by coprecipition method , and then was calcined . We could get Mg-Al metal complex oxides as catalysts. In addition, the ethoxylation of n-octanol was catalysted by the enzymes. The details are listed below.The optimal process parameters of the ethoxylation of n-octanol were proved, whereafter the influence of water on this reaction was studied. Mg-Al metal complex oxides catalytic selectivity got through determining the content of polyther of production was 86. 8%. Mg-Al complex oxides could be separated by filtration and be activated. It was proved that this catalyst had a good generation performance. At various temperatures, such as 160℃ 160℃ 166℃ 172℃ 178℃ 182℃ and 190℃, the corresponding reaction rate constants calculated were 0. 017min-1 0. 0209min-1 0. 0216min-1 0. 0271min-1 0. 0384min-1 and 0. 0479min-1, after we mensurated reaction pressure-time relations at the above each reaction temperature . Furthermore, activation energy obtained by Arrehnius equation was 58. 3KJ/mol.. We made comparison between propertise of narrow range ethoxylated n-octanol obtained with complex oxides and those of broad range ethoxylates in the presence of KOH. It was found that the former were better than the latter.A series of metal complex oxides catalysts with different Mg-Al moles ratios were prepared by coprecipitation. Through a lot of experiments, We found that Mg-Al complex oxides whose moles ratio was 1:1 had the higher catalytic activity for the direct ethoxylation of methyl laurate. Furthermore , Other process conditions for the synthsis of ethoxylated methyl laurate .such as reaction temperature at 150℃ catalyst amount at 0.4% of designed production, were obtained .It was tested that this heterogenerous catalyst could be reused. The properties of ethoxylated methyl laurate with the same average polyaddition were compared with thoseof ethoxylated dedecanol. There were many similar properties, such as surface tension CMC and so on, of this two production , but the former height of foam and cloud point were lower than the latter.Finally, the ethoxylation of n-octanol catalyzed by enzymes was researched. We found that lipase could catalyze this reaction in the presence of the amount of solvent(glycol). The existence of polyether was examined by three ways such as splitting decomposition of phosphoric-acide test Fourier transform infrared absorption spectrum and nuclear magnetic resonance spectrometry. The production was composed of n-octanol ethoxylates polyethylene glycol and a little raw material.