The Preparation of Nanosized Pd/ZSM-23 Bifunctional Catalysts for n-Hexadecane Hydroisomerization by Employing PHMB as the Growth Modifi er  

作　　者：Jiazheng Sun Shuxiang Xiong Qiong Wu Wei Wang Wei Wu 

机构地区：[1]National Center for International Research on Catalytic Technology,Key Laboratory of Functional Inorganic Materials Chemistry(Ministry of Education),Heilongjiang University,Harbin 150080,China

出　　处：《Transactions of Tianjin University》2023年第6期482-491,共10页天津大学学报（英文版）

基　　金：funded by the National Key Research and Development Project,Intergovernmental International Science and Technology Innovation Cooperation Key Project(No.2018YFE0108800);National Natural Science Foundation of China(No.22278115);Heilongjiang Province Natural Science Foundation(No.YQ2021B010).

摘　　要：The development of highly effective metal-zeolite bifunctional catalysts for the hydroisomerization of n-alkanes is a paramount strategy to produce second-generation biofuels with high quality.In this study,polyhexamethylene biguanide hydrochloride(PHMB)is precisely added to the initial gel to synthesize nanosized ZSM-23 zeolites(Z23-x PH).Due to orientation adsorption and steric hindrance effects of PHMB,each sample of Z23-x PH demonstrates enhanced mesoporosity in comparison with the conventional Z23-C zeolite.Furthermore,the Bronsted acid density of the Z23-x PH samples is also signifi cantly reduced due to a reduction in the distribution of framework Al at T2-T5 sites.The corresponding Pd/23-C and Pd/Z23-x PH bifunctional catalysts with 0.5 wt%Pd loading for n-hexadecane hydroisomerization are prepared by incorporating ZSM-23 zeolites as acid supports.According to the catalytic test results,the suitable addition of PHMB can effectively promote the iso-hexadecane yield.The Pd/Z23-2PH catalyst with an n_(PHMB)/n(_Si)molar ratio of 0.002 demonstrates the highest maximum iso-hexadecane yield of 74.1%at an n-hexadecane conversion of 88.3%.Therefore,the employment of PHMB has provided a simple route for the development of highly effective Pd/ZSM-23 catalysts for n-alkane hydroisomerization.

关 键 词：n-Hexadecane hydroisomerization Nanosized ZSM-23 zeolite PHMB Bifunctional catalyst 

分 类 号：TQ426[化学工程]