Ex-situ pre-sulfiding of a hydrotreating catalyst in expansion bed was studied. The influence of presulfiding conditions on sulfiding degree (α) was investigated. The results showed thatαincreased with sulfiding temperature till 370 ℃, where maximum hydrogenation activity was attained. Pyridine-TPD results indicated that acidity increased with sulfiding temperature, which then affected hydrogenation activity of the catalyst. Comparison was made between ex-situ expansion bed and in-situ fixed-bed method. The catalyst presulfided by ex-situ expansion bed exhibited higher α and hydrogenation activity. The suitable condition for ex-situ expansion bed pre-sulfiding was as follows: sulfiding time　≤ 10
t₀; sulfiding temperature = 370 ℃; bed expansion rate = 12%. Better activity was attained when pre-sulfiding and reduction were carried out simultaneously.

A new environmentally-benign Keggin catalyst, LaSiW₁₂O₄₀, was prepared and characterized by FTIR. Catalytic properties of the catalyst were investigated using synthesis of cyclohexanone ethylene ketal from cyclohexanone and ethylene as the probe reaction，including influence of cyclohexanone/ethylene molar ratio，catalyst dosage，reaction time and repeated use of the catalyst. The catalyst exhibited high activity for synthesis of cyclohexanone ethylene ketal，with cyclohexanone conversion of 99.0% under favorable condition. Meanwhile, it featured simplicity in preparation and good properties in repeated use .