Ni-Mg-ZrO2催化剂上煤层甲烷三重整制合成气

摘要

Ni-ZrO2 and Ni-Mg-ZrO2 catalysts were prepared by a co-precipitation method, and then were characterized by BET, XRD, H2-TPR and CO2-TPD techniques. The performances of catalysts in the tri-reforming of coal bed methane to syngas were studied in a fixed bed reactor. The reaction conditions (temperature and feed gas composition) were mainly investigated. The results showed that at f = 800 t, atmospheric pressure, CH4/CO2/H2O/O2/N2 = 1.0/0.45/0. 45/0. 1/0.4, GHSV = 30 000 mL/(g·h), about 99% of CH4 conversion, 65% of CO2 conversion, and Vh/Vco, of 1. 5 could be achieved during 58 h of reaction, which are related to the strong metal-support interaction, the good thermal stability and basic nature of the catalyst. Furthermore, high temperature favors the tri-reforming of methane. By adjusting the feed gas composition, a specific VH2/VCo could be achieved.%采用共沉淀法制备Ni-ZrO2和Ni-Mg-ZrO2催化剂,用BET、XRD、H2-TPR、CO2-TPD等技术对催化剂进行了表征.采用固定床流动反应装置,研究了催化剂在煤层甲烷三重整制合成气反应中的催化性能；考察了反应温度和原料气体组成对反应的影响.实验结果表明,Ni-Mg-ZrO2催化剂在反应温度800℃、常压、空速为30000mL/(g·h)、CH4/CO2/H2O/O2/N2=1.0/0.45/0.45/0.1/0.4的条件下,CH4转化率为99％,CO2转化率为65％左右,生成合成气H2/CO体积比为1.5,并在58 h的实验中催化剂活性和稳定性良好.这主要归因于催化剂中金属和载体之间的强相互作用、催化剂的高热稳定性和强碱性.此外,较高的反应温度有利于甲烷三重整反应的进行；通过调节原料气组成,可以获得不同H2/CO体积比的合成气.