Mg助剂对Co／Mg／HZSM-5催化剂结构及其催化甲烷部分氧化制合成气性能的影响  

Effect of a Mg Promoter on the Structure and Catalytic Performance of a Co/Mg/HZSM-5 Catalyst for the Partial Oxidation of Methane to Syngas

作　　者：张诺伟[1] 黄传敬[1] 匡飞平[1] 高晓晓[1] 翁维正[1] 万惠霖[1] 

机构地区：[1]厦门大学化学化工学院化学系、固体表面物理化学国家重点实验室,福建厦门361005

出　　处：《物理化学学报》2008年第12期2165-2171,共7页Acta Physico-Chimica Sinica

基　　金：国家重点基础研究发展规划项目(2005CB221401,2005CB221408);国家自然科学基金(20433030,20423002);福建省自然科学基金(2007J0168)资助

摘　　要：采用XRD、TEM、H2-TPR、Raman、XPS和活性评价等方法,研究了Mg助剂对Co/Mg/HZSM-5催化剂物理化学性质和甲烷部分氧化(POM)制合成气反应性能的影响.研究发现,在Co/HZSM-5催化剂中添加Mg助剂,可有效地提高催化剂的催化活性和稳定性.在750℃和空速1.0×105mL·h-1·g-1反应条件下,Co/Mg/HZSM-5在连续反应30h的实验时间内催化活性稳定不变,而Co/HZSM-5因其活性中心Co0转化生成CoAl2O4非活性相,反应10h后即迅速失活.催化剂表征结果表明,在Co/Mg/HZSM-5催化剂中钴物种除以Co3O4存在外,一部分钴物种还与Mg助剂发生强相互作用生成较难还原的MgCo2O4,由此导致还原后钴金属的分散度较高.关联催化剂表征和活性评价结果,讨论了催化剂结构与性能之间的关系.The effect of a Mg promoter on the physical and chemical properties, as well as catalytic performance of the Co/Mg/HZSM-5 catalyst for the partial oxidation of methane（POM） to syngas was studied by XRD, H2-TPR, TEM, Raman, XPS and activity measurements. The activity and stability of the Co/HZSM-5 catalyst was effectively improved by Mg modification. At T=750℃ and SV （space velocity）=l.0×10^5 mL·h^-1· g^-1 the Mg-modified catalyst exhibited high activity and good stability during a long run. The unmodified catalyst rapidly deactivated after 10 h on stream. Catalyst deactivation was mainly due to the transformation of CoO into COAl2O4 as indicated by TPR and XPS. For the Co/Mg/HZSM-5 catalyst the Co species, in addition to ones existing as Co3O4, reacted with the Mg promoter to produce MgCo2O4. This structure, after reduction, led to a higher dispersion of Co metal, compared with the Mg-free catalyst. From the results of the characterization and activity measurements, the relationship between catalyst structure and performance was discussed.

关 键 词：Co/HZSM-5催化剂 Mg助剂 甲烷部分氧化 合成气 

分 类 号：TE665.3[石油与天然气工程—油气加工工程]