ZrO_(2)修饰对Co/SiC催化剂的费托合成性能影响  

The promotional effects of ZrO_(2)modification on the activity and selectivity of Co/SiC catalysts for Fischer-Tropsch synthesis

作　　者：王民[1,2] 郭舒鹏 许金山 李留忠[1] 陈从标[2] 马中义[2] 贾丽涛[2] 侯博[2] 李德宝[2] WANG Min;GUO Shupeng;XU Jinshan;LI Liuzhong;CHEN Congbiao;MA Zhongyi;JIA Litao;HOU Bo;LI Debao(Research Institute of Qilu Branch Company,SINOPEC,Zibo 255400 China;China State Key Laboratory of Coal Conversion,Institute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,China)

机构地区：[1]中国石油化工股份有限公司齐鲁分公司研究院,山东淄博255400 [2]中国科学院山西煤炭化学研究所,山西太原030001

出　　处：《燃料化学学报（中英文）》2024年第8期1088-1094,共7页Journal of Fuel Chemistry and Technology

基　　金：山西省自然科学基金(202203021212005);山西省基础研究计划(20210302124466);中央引导地方科技发展资金(YDZJSX2021C041);中国科学院山西煤炭化学研究所创新基金(SCJC-DT-2022-06)资助。

摘　　要：本研究采用ZrO_(2)对SiC表面进行改性,制得系列Co-ZrO_(2)/SiC催化剂,借助N2物理吸附、XRD、H2-TPR、XPS等表征手段对催化剂物化性质进行结构分析,并利用微型固定床反应器对催化剂的活性进行评价,研究ZrO_(2)改性SiC载体对钴基费托合成催化剂的影响。研究结果表明,由于ZrO_(2)体相存在氧空穴等不同的活性位,H2在Co表面被活化后形成的部分H溢流到ZrO_(2)表面并储存到ZrO_(2)表面,而ZrO_(2)与Co之间存在相对较强的相互作用,使得Co周围的H浓度增加,进而Co/SiC催化剂的还原度显著增加。同时,ZrO_(2)与SiC表面的无定形相发生相互作用形成Zr−O−Si键。由于Si(1.90)的电负性高于Zr(1.33),部分电子可以通过Zr-O-Si结构从Zr转向Si,形成富电子的SiOxCy相和SiO_(2)相。从而降低了SiC表面无定形相的对Co物相吸电子能力,减弱了Co与SiC表面的无定形相的相互作用,进而提高了Co相的电子密度。采用ZrO_(2)对SiC进行修饰后,同时提高了Co/SiC催化剂中Co物相的电子密度和还原度,使得催化剂对长链烃的选择性显著提升。Co/SiC catalysts have exhibited excellent performance in Fischer-Tropsch synthesis reaction.However,few research focuses on investigating the effect of SiC supports surface properties of on catalyst performance.In this study,ZrO_(2)was utilized to modify the SiC surface,leading to the preparation of a series of Co-ZrO_(2)/SiC catalysts.The physicochemical properties of the catalyst were comprehensively analyzed by using N2 adsorption,XRD,H2-TPR,XPS analyses.Catalytic performance was evaluated using a fixed bed reactor,shedding light on the effect of ZrO_(2)modified SiC support on cobalt-based Fischer-Tropsch synthesis catalysts.The results indicated that ZrO_(2)surface modification on SiC resulted in an enhanced reduction degree of Co/SiC catalysts.Additionally,ZrO_(2)exhibited strong interaction with the amorphous phase on the SiC surface,thereby weakening the interaction between Co and the amorphous phase.This led to an increase in the electron density of cobalt species,consequently improving the selectivity of Co/SiC catalysts towards long-chain hydrocarbons.

关 键 词：钴基催化剂 SIC ZrO_(2) 费托合成 

分 类 号：TQ546[化学工程—煤化学工程]