【作者】 王磊；

【导师】 刘靖；

【作者基本信息】 大连理工大学 ， 工业催化， 2015， 硕士

【摘要】 在现代炼油工业中,正构烷烃的加氢异构化生成支链烷烃是一种重要的加工过程,已广泛应用于生产高辛烷值汽油。特别是由于汽车工业的高速发展对高辛烷值汽油的需求日益增多,因此,寻找应用于将低辛烷值C5-C8直链烷烃转变为高辛烷值的多支链异构体的异构化催化剂已经成为世界上许多研究工作者的目标。ZSM-22分子筛具有一维十元环孔道结构、孔径为0.44 nm 0.55 nm,由于其独特的孔道结构和酸性使其在正构烷烃的异构化反应中具有优势,常被用于双功能催化剂的酸性载体。本论文研究目的在于寻找正辛烷在ZSM-22催化剂上进行异构化反应的最合适的条件,包括催化剂的制备条件和反应条件。本论文主要的内容包括如下：1.对于Pt/ZSM-22催化剂,将反应压力固定为3 MPa并且体系中的氢气质量流量固定,系统考察反应温度和空速的影响,发现在反应温度为310℃、空速为0.7h-1的条件下,此时得到的异构化产物收率最大,达到40.32%。进一步考察催化剂的还原时间和反应压力的影响,得到最合适的还原时间为8h,最合适的反应压力为3 MPa。2.对于Pt-P/ZSM-22催化剂,将反应压力固定为3MPa并且将体系中的氢气质量流量固定,系统考察反应温度和空速的影响,发现在反应温度为320℃、空速为1.05h-1的条件下,此时得到的异构化产物收率最大,达到53.82%。进一步考察氢气／烃体积比的影响,发现氢气／烃体积比在200-400范围内较合适。在最优实验条件下,此催化剂在110h内有较好的稳定性。3.通过制备两个系列的催化剂考察不同的改性方法对催化剂催化效果的影响,研究发现,硝酸铵的处理次数,水蒸气钝化和磷改性的处理顺序对Pt-P/ZSM-22催化剂的影响最大。采用三种评价方法对比不同的催化剂,不同的评价方法会得到不同的结论。更多还原

【Abstract】 Hydroisomerization of n-alkanes to their branched isomers is one of the important processes in the modern petroleum refining industry that has been widely applied in producing high-octane gasoline. In particular, with the ever-increasing demand for high-octane gasoline due to the rapid development of the automobile industry, searching for catalysts to isomerize C5-C8 n-alkanes of low octane rating into multi-branched isomers of high octane rating has been the subject of many investigations around the world.As an acidic carrier of bifunctional catalysts, ZSM-22 with a one-dimensional 10-membered-ring channel system of 0.44 nm 0.55 nm has shown its advantages in n-alkane isomerization due to its distinct pore structure and acidity. The study is aiming at searching for optimum condition for catalytic performance of isomerization of n-octane on ZSM-22 catalysts, including catalyst preparation and reaction conditions.The main contents of this thesis are as follows:1. Isomerization of n-octane on Pt/ZSM-22 catalyst was maintained at 40.32% yield of isomerization products under the conditions of 583 K,3.0 MPa, volumetric H2/n-octane ratio 300, and weight hour space velocity (WHSV) 0.7 h-1. Further, effects of reduction time and reaction pressure for catalyst were investigated, it was found that reduction time 8h, reaction pressure 3 MPa were optimal conditions.2. Isomerization of n-octane on Pt-P/ZSM-22 catalyst was maintained at 53.82% yield of isomerization products under the conditions of 593 K,3.0 MPa, volumetric H/2/n-octane ratio 200, and weight hour space velocity (WHSV) 1.05 h-1. Further, the stability of this catalyst was investigated, it has a good stability in 110h.3. Effects of different modification methods for catalysts were investigated by two series of ZSM-22 catalysts, it was found that the impact of the times of ammonium exchanged, the sequence of water vapor passivation and phosphorus modification treatment on Pt-P/ZSM-22 catalyst is biggest. The catalysts were compared by using three evaluation methods, it was found that different evaluation methods get the different conclusions.更多还原