摘要
采用常规水热合成法合成了ZSM-22和ZSM-23分子筛,进而制备了分别含有上述分子筛的催化剂,并借助XRD、SEM、NH3-TPD和Py-IR表征了这两种分子筛和催化剂的结构和酸性,同时以正十二烷为模型化合物,采用固定床反应器研究了Pt/ZSM-22和Pt/ZSM-23催化剂上正十二烷加氢异构反应性能。结果表明,在这种模型反应基础上,催化剂的反应活性和选择性主要取决于催化剂的酸量和酸强度以及酸分布,相对而言,ZSM-22分子筛催化剂由于其弱酸和中等强度酸的含量较高,具有更佳的异构化选择性。
ZSM-22 and ZSM-23 zeolites were synthesized via conventional hydrothermal methods.Then,two kinds of catalysts contained aforementioned molecular sieves were prepared respectively.The typical structure and acidity of molecular sieves and catalysts were characterized by using XRD,SEM,NH3-TPD and Py-IR.Then the hydroisomerization performance of these catalysts was studied in a continuous down-flow fixed bed,a stainless steel tubular reactor,where n-dodecane was chosen as the probe molecule.The reaction results indicated that the activity of the catalysts mainly depended on their acid quantity,acid intensity and acid distribution.ZSM-22 zeolite based catalyst with the relative higher amount of weak and mild acid sites exhibited better hydroisomerization selectivity than ZSM-23 zeolite based catalyst.
出处
《化工进展》
EI
CAS
CSCD
北大核心
2012年第11期2477-2482,2487,共7页
Chemical Industry and Engineering Progress
基金
中国石油天然气集团公司项目(080303-01
2009A-3801-04)
