加氢尾油催化裂解生产润滑油基础油催化剂活性稳定性研究

Study on activity stability of catalytic cracking catalyst for producing lube base oil from hydrocracking bottoms

以加氢尾油为原料,在固定床反应器上利用自制催化裂解催化剂进行中试试验。考察了操作条件及原料中的碱性氮化物对催化剂活性稳定性的影响。结果表明,操作温度的不平稳、空速及压力的提高均会造成催化剂活性稳定性变差,运转周期缩短。大分子碱性氮化物可以毒化催化剂外表面活性中心,小分子碱性氮化物可以进入催化剂孔道,造成催化剂活性中心全部失活。在实际生产中,通过严格控制温度变化,采用低空速及常压,对含碱性氮化物较多的原料进行必要的预处理可以最大限度地延长催化剂运转周期。

A pilot test was carried out on a fixed-bed reactor for catalytic cracking of hydrocracking bot- toms over self-developed catalyst. Influence of operation condition and basic nitrogen compounds in the feed oil on activity stability of the catalyst was investigated. The results showed that instability of opera- tion temperature and increase in space velocity and pressure would cause deterioration of the activity sta- bility, resulting in shorter service cycle. Big basic nitrogen compounds （BNC） molecules poisoned the active sites on external surface of the catalyst, while small BNC molecules entered pore channels of the catalyst, both caused deactivation of the active sites. Strictly-controUed operating temperature, lower space velocity, atmospheric pressure and necessary pre-treatment of the feed oil containing much BNC would help lengthen the service cycle.