铝对固体超强酸/介孔分子筛催化性能的促进作用

采用浆态直接浸渍-焙烧方法制备了铝促进的固体超强酸／介孔分子筛材料，并采用XRD、N2吸附、吡啶吸附IR、反应表征等方法对其结构及性能进行了表征。铝的引入有利于形成和稳定样品表面的B酸，有助于稳定表面硫物种，而样品的比表面和孔容随着铝的加入变化不大。添加适量的铝能够大大提高正丁烷异构化的催化活性。

Promotion Effect of Al on MCM-41 Supported Strong Solid Acid Materials

Al-promoted sulfated zirconia (SZ) was confined inside pure-silica MCM-41 (abbreviated as SZA/MCM-41). It was prepared by slurry impregnation followed by decomposition of the metal sulfate. The effects of aluminum on these samples were investigated by powder XRD, N2 adsorption and DRIFT techniques in detail. The experimental results show that the ordered porous host structure is still maintained in the catalyst. Sulfated zirconia is in meta-stable tetragonal phase. The IR spectrum of the adsorbed pyridine showed that the amounts of Bronsted acid sited on the SZA/MCM-41 are improved comparing to SZ/MCM-41. The addition of aluminum can help the retention of sulfur species on the surface of the composites. Between SZ/MCM-41 and SZA/MCM-41, no significant changes in structural properties such as surface areas, pore volumes etc. can be found. In comparison to SZ/MCM-41 without aluminum, the catalytic activities of the Al-promoted catalysts are greatly improved. The best conversion is achieved when the catalyst is promoted by 1.1%(wt) aluminum and calcined at 720oC.