Dimethyl ether synthesis from methanol over diatomite catalyst modified using nitric acid treatment

Abstract

Dimethyl ether synthesis from methanol over diatomite catalysts modified using nitric acid was investigated. The catalytic performance of diatomite was tested in a fixed-bed reactor under atmospheric pressure and within the temperature range of 250–350°C. It was discovered that high acidity of the catalyst yielded a higher methanol conversion rate. Moreover, it was revealed that the acidity of the catalyst surface was controlled by Al(IV) ions whereas basicity of the catalyst surface was determined by Al(V) and Al(VI) ions. From this finding, the authors were able to propose the mechanism of DME synthesis from methanol over treated diatomite.