Direct Alkoxylation Of Carboxyl Acid Ester In One Step Process

A series of Al-Mg composite oxide catalysts possessing acid-base active sites (SCATs,YCATs, HCATs) were designed and studied in aid of catalysizing one step alkoxylation(ethoxylation or propoxylation) of saturated/ unsaturated carboxyl acid esters. The optimumcatalysts for ethoxylation of ethyl acetate or butyl acrylate and propoxylation of ethyl acetatewere screened out respectively. The amelioration of the manufacture process and surfacemodification of the catalyst for ethoxylation of ethyl acetate were investigated in thisdissertation as well. A technique was described about producing olig-ethylene glycol ethyl ether acetate(EGEEA) by inserting ethylene oxide (EO) into the carbonyl carbon and the ester oxygen ofethyl acetate (EA) with catalyst SCATs. The product was characterized by FT-IR, ESI-MSand GC-MS. It was found that the catalyst, SCAT-5, has the highest production selectivity forEGEEA. The optimum selectivity of EGEEA (51.5%, w/w) was obtained under thefollowing suitable conditions: the amount of catalyst 1.1 g/100 g ethyl acetate, the initialpressure 0.1 MPa, the reaction temperature 145-150 oC, the molar ratio of EA to EO 5:1 andthe feeding rate of EO 0.25 g?min-1. The production selectivity of EGEEA was not decreaseddramatically after the catalyst had been used ten times and it revealed that this kind of catalysthas good catalysis stability. The product of propylene oxide (PO) reacted with ethyl acetate catalyzed by YCATs wasidentified to be olig-propylene glycol ethyl ether acetate (PGEEA) by FT-IR and GC-MSanalysis. The catalyst YCAT-5 has the highest production selectivity of PGEEA. Theoptimum selectivity of PGEEA (50.7%, w/w) was obtained under following suitableconditions: catalyst 1.1 g/100 g ethyl acetate, initial pressure 0.1 MPa, reaction temperature140-145 oC, molar ratio of EA to PO 8:1 and feeding rate of PO 0.25 g?min-1. The catalystmodified by KOH has a higher selectivity of PGEEA (60.3%, w/w). It was explored that deposition-supported loading technique, spraying-desiccation processand surface-modification were applied to produce catalysts for ethoxylation of ethyl acetate.The catalyst prepared by an isovolumetric impregnation-supported technique using alumina orsilica gel showed better catalysis activity and selectivity of EGEEA during the precess of EOinserting into ethyl acrylate. Spraying-desiccation process obviously shortened the period ofpreparing catalyst, and the capability of catalyst made by this process did not changeobviously. The catalyst modified by KOH–ethanol increased the selectivity of EGEEA to64.8% and total selectivity of EGEEA and DEGEEA to 89.8%. The optimum conditions ofmodified process was: the amount of KOH 3 g/100 g CAT, the volume of ethanol 2000mL/100 g CAT, reaction time 0.5 hour and drying temperature 105oC. Ethylene oxide (EO) could be inserted into the carbonyl carbon and the ester oxygen ofbutyl acrylate via catalysts HCATs, which was confirmed by GC analysis of the product'shydrolysate together with FT-IR, GC-MS, ESI-MS analysis of the products. The screening ofpolymerisation inhibitor showed that 4-Oxo-2,2,6,6-tetramethyl piperdine-1-oxyl (TMPO)was the most effective inhibitor during the reaction process. The catalyst comprising ironelement showed some inhibition. In the present of TMPO and using 90-110 oC petroleumether as dilutor, the production of narrow-distributing polyethylene glycol monobutyl etheracrylate (EGBEA) with average addition EO number of 10 could be achieved in one stepprocess catalyzed by HCAT1.