Influence of acid-base properties of ZnMgAl-mixed oxides for the synthesis of 1-methoxy-2-propanol

The synthesis of 1-methoxy-2-propanol from propylene oxide and methanol was investigated with a series of ZnMgAl catalysts derived from hydrotalcite-like compounds. The mixed oxides were characterized using XRD, TG-DTG, N2 adsorption analysis. NH3-TPD and CO2-TPD methods were used to measure the acid-base properties of the catalysts. Under the optimal reaction condition (the amount of the catalysts, 1.8%; methanol/propylene oxide molar ratio, 5:1; temperature, 393 K; and time, 3 h), ZnMgAl-2 led to the highest propylene oxide conversion of 95.9% and 1-methoxy-2-propanol selectivity of 90.9%. The high catalytic activity and selectivity of ZnMgAl-2 were attributed to the presence of a high density of acidic sites and a medium basic sites.