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Isophorone extremely versatile as an important fine chemical raw materials and intermediates , and high added value . In recent years, with the green synthesis route of acetone gas-solid phase synthesis of isophorone attention , at home and abroad on the use of solid catalyst is more extensive. In this study, by using ammonia as the precipitating agent , prepared by coprecipitation a of a series MgCaAl composite acid-base solid catalyst , activity was evaluated through a fixed bed reactor , and analysis of the structure and nature of the catalyst by TPD, XRD characterization means . Catalyst compared with MgAl system , MgCaAl composite oxide catalyst catalytic activity is superior to the MgAl systems catalyst . Study preparation method through the system , adding ion to metal molar ratio , the precipitation pH value , crystallization temperature (co-precipitation of the preparation conditions of the temperature) and the calcination temperature and the like , to determine the existing experimental conditions the preparation of such catalysts are more suitable conditions as : and stream coprecipitation method , Mg / Ca / Al molar ratio of 10:1:10 , precipitation at pH 9.0 , the crystallization temperature of 70 ° C , the calcination temperature of 600 ℃, the catalyst has good catalytic activity . The acetone conversion was 32.8%, and selectivity was 84.8% isophorone . The experiment investigated the influence of the reaction temperature , diluents, and other factors in the catalyst evaluation condition . The experimental results shows that : appropriate to reduce the reaction temperature can reduce the generation of high boiling components , the the acetone conversion rate and isophorone selectivity of 32.3% and 86.5% . The experimental results show that , MgCaAl ternary complex oxide catalyst surface of the acid - base centers properties ( strength and density) , more suitable for a synthesis reaction of isophorone , and the catalyst has good stability .
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