ZSM-12分子筛合成、表征与正癸烷加氢异构化反应催化性能

发布时间：2018-05-05 01:35

本文选题：ZSM- + 表征　；参考：《石油学报(石油加工)》2017年03期

【摘要】：以甲基三乙基溴化铵为模板剂,硅溶胶为硅源,Al_2(SO_4)_3·18H_2O为铝源制备了2种不同n(Si)/n(Al)的ZSM-12分子筛。采用XRD、XRF、氮气吸附-脱附、吡啶吸附红外光谱、SEM和TEM等表征了合成的分子筛样品。以正癸烷为模型化合物对合成的ZSM-12制备的Pt催化剂进行加氢异构化反应评价。结果表明,合成分子筛为纯相ZSM-12晶体,合成过程中物料反应完全,且铝原子完全处于分子筛骨架中,分子筛Br9nsted酸中心数量和强度随n(Si)/n(Al)变化而改变。以高n(Si)/n(Al)合成的ZSM-12分子筛为载体制备的Pt催化剂具有较高的异构选择性,且产物中含有较多的多支链异构体。将催化剂催化性能与分子筛物化性质关联得出,ZSM-12分子筛孔径较大,为了提高异构选择性和多支链异构体产率,需要更少和更弱的Br9nsted酸性中心。
[Abstract]:Using methyl triethylammonium bromide as template and silica sol as silicon source, two kinds of ZSM-12 molecular sieves with different nnsSiN / nc-Al were prepared by using 18H_2O as aluminum source. The synthesized molecular sieve samples were characterized by XRF, nitrogen adsorption-desorption, pyridine adsorption infrared spectroscopy and TEM. The hydroisomerization of Pt catalyst prepared by synthetic ZSM-12 was evaluated using n-decane as model compound. The results show that the synthetic molecular sieve is pure phase ZSM-12 crystal, the material reaction is complete during the synthesis process, and the aluminum atom is completely in the molecular sieve skeleton. The number and strength of the acid center of the molecular sieve Br9nsted change with the change of nn Si Si / n O Al. The Pt catalyst prepared on the support of ZSM-12 molecular sieve synthesized by high nnn Si / nn Al has high isomerization selectivity and there are many branched chain isomers in the product. It was found that the pore size of ZSM-12 molecular sieve was larger by correlating the catalytic activity with the physicochemical properties of molecular sieve. In order to improve the isoselectivity and the yield of multi-branched isomers, fewer and weaker Br9nsted acidic centers were needed.
【作者单位】：中国石化石油化工科学研究院;
【基金】：中国石油化工股份有限公司项目(R113017)资助
【分类号】：O643.36

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