摘要
采用浸渍法在不同干燥和焙烧温度下制备一系列WNi型加氢裂化催化剂,采用N2-物理吸附、NH3-TPD、XRD、TPR等手段对催化剂进行表征,并用十二烷为模型化合物考察催化剂的加氢裂化性能。结果表明:随着焙烧温度的升高,催化剂的比表面积略有降低,孔径变大,孔体积变化不大;随着焙烧温度的升高,催化剂的酸量呈先增加后降低的变化趋势,在400℃时达到最大值,当焙烧温度提高到600℃时,金属组分在载体表面发生聚集;加氢裂化催化剂的活性随着焙烧温度的升高呈先增加后降低的变化趋势,峰值出现在焙烧温度为500℃处。说明适宜的焙烧温度有利于提高催化剂的催化性能,当催化剂经过高温焙烧时,会对其活性产生抑制作用。干燥温度由200℃降到120℃时,催化剂的孔体积和孔径提高,比表面积略有降低,酸量基本不变,催化活性提高。
A series of W/Ni-based hydrocracking catalysts dried and calcined under various temperatures was prepared by impregnation method. The prepared catalysts were characterized by means of Nz adsorption,NH3-TPD,XRD and TPR technique; the hydrocracking performance of these catalysts was investigated using dodecane as model compound. The results showed that with the increase of calcination temperature,the specific surface area of the catalyst decreased slightly,pore size increased and pore volume was basically unchanged. The acid amount and hydrocracking activity of the catalyst both showed a tendency to ascend firstly, followed to descend with the in.crease of calcination temperature, and the peak value for the former and the latter was at 400 ℃ and 500℃ ,respectively. When the calcination tempera ture reached 600 ℃ ,aggregation of the metal components happened on the surface of the carrier. On the whole,catalyst calcined under suitable temperature could improve its performance, yet high temperature calcination might suppress the activity of the catalyst. Reducing the catalyst drying temperature from 200 ℃ to 120℃ ,the specific surface area of the catalyst decreased,pore size and pore volume increased, acid amount was basically unchanged and the catalyst activity enhanced.
出处
《石油炼制与化工》
CAS
CSCD
北大核心
2012年第1期36-40,共5页
Petroleum Processing and Petrochemicals
关键词
焙烧温度
干燥温度
加氢裂化催化剂
活性
calcination temperature
drying temperature
hydrocracking
catalyst
activity
