一种煤基合成气制合成天然气用Sc_2O_3促进Ni-ZrO_2高效新型甲烷化催化剂  

A Highly Efficient Sc_2O_3-promoted Ni-ZrO_2 Catalyst for Methanation of Coal-based Syngas to Produce Synthetic Natural Gas

作　　者：代陈[1] 刘志铭[1] 谢建榕[1] 林国栋[1] 张鸿斌[1] 

机构地区：[1]厦门大学化学化工学院,固体表面物理化学国家重点实验室,醇醚酯化工清洁生产国家工程实验室,福建厦门361005

出　　处：《厦门大学学报（自然科学版）》2013年第5期650-654,共5页Journal of Xiamen University：Natural Science

基　　金：国家重点基础研究发展计划(973)项目(2011CBA00508);优秀国家重点实验室基金项目(20923004);教育部创新团队项目(IRT1036)

摘　　要：用Sc2O3作为促进剂，研发出一种Sc2O3掺杂的高效新型Ni—ZrO2基催化剂，该催化剂对CO和CO2共甲烷化制合成天然气（SNG）显示出高的活性和优异的热稳定性．在组成经优化的Ni5Zr3Sc1催化剂上，0．1MPa，573K，V（H2）：V（CO）：V（CO2）：V（N2）=75：15：5：5，出口空速GHSV-40000mL／（h·g）的反应条件下，在反应开始之后的20～332h的反应过程中，CO和CO2的转化率一直分别保持在100％和85％的高水平，产物甲烷的选择性一直保持在100％，耐热试验结果显示，在973K下经历24h甲烷化反应、而后降至573K的Niszr3sc。催化剂试样上，（CO＋CO2）的总转化率仍能稳定地保持在80．2％的水平；而不含Sc2O3。的原基质催化剂（NisZra）在经历相同耐热试验过程之后的（CO＋CO2）总转化率骤降至2．7％，暗示其因烧结而失活．催化剂的表征结果证实，可观量的Sc^3＋溶解入ZrO2晶格导致具有c—ZrO2结构的单一C-（Zr-Sc）Oy相的生成并使其稳定化，这类c-（Zr—Sc）O3相与Ni6Zr3Sc1催化剂的高活性，尤其与优良的热稳定性，密切相关．A type of highly efficient Ni-ZrO2 catalysts doped with Sc2 O3 for co-methanation of CO and CO2 was developed, and dis played high activity and excellent thermal stability. Over a Ni6 Zr3 Sea catalyst under the reaction conditions of 0. 1 MPa, ,573 K, V（ H2 ） ： V（CO） ： V（CO2 ） ： V （ N2 ） = 75 ： 15 ： 5 = 5, GHSV = 40 000 mL/（ h, g） （ outlet）, the observed conversion of CO and CO2 maintained continuously at high levels of 100% and 85 %, respectively,during 20-332 h after the reaction started, with the corresponding selectivity of CH4 product being 100 %. The results of heat-resisting test showed that, over the Ni6 Zr3 Se1 catalyst after undergoing 24 h of the methanation operation at 973 K followed by going down to 573 K,the total conversion of （CO＋CO2） still maintained stable at the level of 80.2%, whereas that of the Sc20a-free Ni6 Zr4 catalyst after undergoing the same heat-resisting test fell to 2.7 %, impl- ying that it was deactivated due to sintering. The results of the catalyst characterization demonstrated that solution of a considerable amount of Sca＋ in the ZrO2 lattice resulted in the formation of （Zr-Sc）Oy composite oxide with simple c-ZrO2 phase-structure, which was closely associated with the high activity,especially the extremely high thermal stability,of the Ni6 Zr3 Sc1 catalyst.

关 键 词：Ni—ZrO2催化剂 Sc2O3-促进Ni-ZrO2催化剂 CO CO2 共甲烷化 合成天然气 

分 类 号：O643.36[理学—物理化学]