高稳定甲烷干重整Ni基催化剂的制备及其催化性能研究  

Preparation and catalytic performance of highly stable methane dry reforming Ni-based catalyst

作　　者：黄艳丽 李晓东 黄伟[1] HUANG Yan-li;LI Xiao-dong;HUANG Wei(Key Laboratory of Coal Science and Technology,Ministry of Education of China and Shanxi Province,Taiyuan University of Technology,Taiyuan 030024,China;School of Chemistry and Chemical Engineering,Jinzhong University,Jinzhong 030619,China)

机构地区：[1]太原理工大学煤科学与技术教育部和山西省重点实验室,山西太原030024 [2]晋中学院化学化工学院,山西晋中030619

出　　处：《天然气化工—C1化学与化工》2020年第5期18-23,38,共7页Natural Gas Chemical Industry

基　　金：国家高技术研究发展计划(2013AA051201);国家科技支撑计划(2013BAC14B04);国家自然科学基金重点资助项目(21336006)。

摘　　要：制备高稳定的Ni基催化剂一直是甲烷干重整(DRM)研究的重点。采用简单的一步水热法,通过调变n(HMT)/n(Ni+Mg+Al)制备了一系列Ce、Zr和Mo改性的Ni Mg Al类水滑石前驱体,再经过焙烧和还原处理后得到Ni/MoCeZr-MgAl(O)催化剂。将该催化剂用于催化甲烷干重整制合成气,考察了制备时不同n(HMT)/n(Ni+Mg+Al)对催化剂性能的影响。借助XRD、BET、H2-TPR、CO脉冲吸附、CO2-TPD和O2-TPO等技术对各个阶段催化剂的结构进行了表征。结果表明,催化剂的催化性能很大程度上取决于n(HMT)/n(Ni+Mg+Al),当比值为2时制备的催化剂性能最佳,在反应温度为900℃,GHSV=60000 mL/(g·h)时,其甲烷转化率能维持在95%左右长达600 h,且积炭速率仅有0.20 mg/(g·h)。高的金属分散度(15.7%)、较大的比表面积、较多的可还原物种及较少的积炭是其高活性和稳定性的原因。该研究为合成稳定高效的DRM催化剂提供了一种简单有效的方法。The preparation of highly stable Ni-based catalysts has always been the focus of methane dry reforming(DRM)filed. A series of Ce, Zr and Mo modified Ni MgAl hydrotalcite-like compounds(HTLcs) precursors were prepared by one-step hydrothermal method and tuning n(HMT)/n(Ni+Mg+Al), which were calcined and reduced to obtain Ni/MoCeZr-MgAl(O) catalysts. The effect of n(HMT)/n(Ni+Mg+Al) on the performance of catalysts in dry reforming of methane to syngas was investigated. The structures of the catalysts at each stage were characterized by XRD, BET, H2-TPR, CO pulse adsorption, CO2-TPD and O2-TPO techniques. The results revealed that the catalytic performance largely depended on n(HMT)/n(Ni+Mg+Al) and the best catalytic performance could be obtained at n(HMT)/n(Ni+Mg+Al) of 2. Under the conditions of 900 ℃ and GHSV=60,000 mL/(g·h), the conversion of CH4 could be maintained at 95% for 600 h, and the coking rate was only 0.20 mg/(g·h). High metal dispersion(15.7%), large specific surface area,more reducible species and less carbon deposition were responsible for its high activity and stability. A simple and effective method for the synthesis of stable and efficient DRM catalysts is provided through the study.

关 键 词：六次甲基四胺 甲烷干重整 水热法 类水滑石 NI基催化剂 

分 类 号：O643.32[理学—物理化学]