文献类型：期刊文献

英文题名：Methanol promoted naphtha catalytic pyrolysis to light olefins on Zn-modified high-silicon HZSM-5 zeolite catalysts

作者：Cheng, Qi-tong[1];Shen, Ben-xian[1];Sun, Hui[1];Zhao, Ji-gang[1];Liu, Ji-chang[1]

机构：[1]East China Univ Sci & Technol, Res Inst Petr Proc, Shanghai 200237, Peoples R China

年份：2019

卷号：9

期号：36

起止页码：20818

外文期刊名：RSC ADVANCES

收录：;EI(收录号：20192807169708);WOS:【SCI-EXPANDED(收录号:WOS:000474306500036)】；

基金：This work is financially supported by the National Natural Science Foundation of China (Grant 91634112, 21878097) and the Natural Science Foundation of Shanghai (Grant 16ZR1408100).

语种：英文

外文关键词：Pyrolysis - Silicon - Naphthas - Scanning electron microscopy - Fourier transform infrared spectroscopy - Methanol - Temperature programmed desorption - Zeolites - Chemical reactors - Catalysts - Ion exchange - Spectrometry - X ray photoelectron spectroscopy - Optical emission spectroscopy - Inductively coupled plasma - X ray diffraction - Zinc

摘要：The methanol promoted naphtha catalytic pyrolysis system to obtain light olefins (ethylene and propylene) was studied over Zn-modified high-silicon HZSM-5 (Zn/HZSM-5) catalysts. Compared with the individual naphtha catalytic pyrolysis to light olefins, the addition of methanol remarkably improved the naphtha conversion and the yield of the light olefins. All Zn/HZSM-5 samples were characterized by using a variety of techniques including inductively coupled plasma-optical emission spectrometry (ICP-OES), X-ray diffraction (XRD), scanning electron microscopy (SEM), N-2 adsorption, NH3-temperature programmed desorption (NH3-TPD), X-ray photoelectron spectroscopy (XPS), pyridine adsorption infrared spectroscopy (Py-IR), and Fourier transform infrared spectroscopy (FT-IR). The performances of the catalysts for methanol promoted naphtha catalytic pyrolysis were evaluated in a fixed-bed reactor. In the methanol promoted naphtha catalytic pyrolysis reaction, the yield of the light olefins was strongly dependent on the reaction conditions and the degree of Zn ion-exchange. Due to the heterogeneous distribution of the protons of high silicon ZSM-5, two types of Lewis acid sites were formed by the interaction of Zn with hydroxyl groups (OH) adsorbed on HZSM-5. The 0.3-Zn/HZSM-5 (0.3 mol L-1 Zn ion-exchange HZSM-5) sample holds a comparatively high light olefin yield of 51.7 wt% possibly because of the moderate density and distribution of the acid sites on the catalyst.