Abstract:

Study on two-stage hydrocracking process and supporting catalyst for maximum production of heavy naphtha from straight run diesel is carried out. The results show that under different conversion depths, catalyst B has the highest yield of heavy naphtha, followed by catalyst A, and catalyst C has the lowest yield. When flexible hydrocracking catalyst B with suitable activity is selected for both the first stage and the second hydrocracking, the selectivity of heavy naphtha is the best. When the first stage conversion depth is 60% and the second stage conversion depth is 50%, the yield of heavy naphtha reaches 73.15%, and the aromatic potential content is 49%, which can be used as high-quality feedstocks for catalytic reforming unit. By optimizing the process, some diesel feedstocks are introduced into the secondary reactor to further improve the selectivity of heavy naphtha. After optimization, the yield of heavy naphtha has increased from 73.15% to 73.34%, while the yield of liquid products has increased from 92.20% to 92.25%.

Key words: straight-run diesel, heavy naphtha, two-stage hydrocracking, catalyst, selectivity, conversion depth, yield, process optimization

摘要：

开展了以直馏柴油为原料最大量生产重石脑油的两段加氢裂化工艺及配套催化剂的研究。结果表明：在不同转化深度下，采用催化剂B时重石脑油收率最高，催化剂A次之，催化剂C最低。一段加氢裂化催化剂与二段加氢裂化催化剂均选择活性适宜的灵活型加氢裂化催化剂B时重石脑油选择性最佳，一段转化深度60%、二段转化深度50%的工艺条件下，重石脑油收率达到73.15%,同时芳烃潜含量为49%,可作为优质的催化重整装置原料。通过工艺优化在二段反应器引入部分柴油原料，进一步提升重石脑油选择性，优化后重石脑油收率由73.15%提升至73.34%,同时液体产品收率由92.20%提高至92.25%。

关键词: 直馏柴油, 重石脑油, 两段加氢裂化, 催化剂, 选择性, 转化深度, 收率, 工艺优化