SO_4^(2-)/TiO_2固体超强酸制备及其气相催化乙醇与叔丁醇制备ETBE性能

Preparation of SO_4^(2-)/TiO_2 Super-acid Catalyst and Activity for Gas Phase Synthesis of Ethyl Tert-butyl Ether from Ethanol and Tert -butyl Alcohol

选取TiO2为载体,采用沉淀-浸渍法制备了负载型SO24-/TiO2固体超强酸催化剂。并运用IR、XRD、比表面积、全硫测定、酸性测定等表征了催化剂。测试结果表明,所制备的催化剂具有固体酸的特征,酸性与焙烧温度有关,适当提高焙烧温度有利于样品酸强度的提高,但焙烧温度过高会导致脱硫;浸渍液H2SO4浓度高有利于提高催化剂的硫含量,但是浓度过高,会在催化剂表面形成硫酸盐,从而降低催化剂的比表面积,酸性降低。气相催化乙醇与叔丁醇制备ETBE的催化活性表明,ETBE的选择性为43.60%。

In this paper, TiO_2 was used as carrier, solid super-acid catalysts SO~ 2- _4/TiO_2 were prepared by precipitation-impregnation method and characterized by XRD, IR, BET surface area, chemical anlysis,etc. The results showed that catalysts had the characteristic of solid super acid. It was found that the acidity of solid super acid was related to the baking temperature, and higher baking temperature was advantageous to increase the acidity. But too high baking temperature resulted in the decrease of the sulfur content and the acidity. It was also found that the higher concentration of H_2SO_4 is benifit to increase the acidity, but too high concentration of H_2SO_4 make the sulfate formation,surface area and acidity decrease.The catalytic activity for gas phase synthesis ETBE from tert-butyl alcohol and ethanol was investigated and the results showed that the ETBE selectivity was 43.60%.