摘要
负载型催化剂具有活性组分分散度好、机械强度高等优点,在工业中应用广泛。围绕合成气经费托路线直接制备烯烃(FTO),本工作详细研究了Na助剂对SiO_(2)负载型Co_(2)C基催化剂构效关系的影响,发现随着Na含量的提高,CH_(4)选择性降低,烯烷比(物质的量之比)提高,烯烃选择性上升。结构表征表明:Na助剂的添加可有效调控SiO_(2)载体表面性质,弱化金属-载体间相互作用,促进CoMn复合氧化物的形成,同时加速Co物种的碳化速率,最终有利于暴露(101)和(020)晶面的棱柱状Co_(2)C纳米结构的形成,从而体现出良好的FTO催化性能。
Supported catalysts are widely used in industry with the advantages of high dispersion of active components and high mechanical strength.Herein,the effects of sodium on the structure-performance relationship of Co_(2)C-based supported catalysts for Fischer-Tropsch to olefins were studied.It was found that with the increase of Na content,both olefins selectivity and olefins/paraffins ratio increased gradually with decreasing methane selectivity.Combined with structure characterization,it was suggested that the addition of Na promoter could effectively regulate the surface property of SiO_(2)support and weaken the support-metal interaction,which would accelerate the carbonization rate of Co species and benefit the formation of Co_(2)C nanoprisms.
作者
贾汭泽
林铁军
安芸蕾
龚坤
钟良枢
孙予罕
JIA Ruize;LIN Tiejun;AN Yunlei;GONG Kun;ZHONG Liangshu;SUN Yuhan(CAS Key Laboratory of Low-carbon Conversion Science&Engineering,Shanghai Advanced Research Institute,Shanghai 201203,China;University of the Chinese Academy of Sciences,Beijing 100049,China)
出处
《化学反应工程与工艺》
CAS
2022年第2期97-106,共10页
Chemical Reaction Engineering and Technology
基金
国家自然科学基金(91945301)
科技部重点研发计划(2017YFB0602202)。
关键词
合成气转化
费托反应
烯烃
碳化钴
助剂效应
syngas conversion
Fischer-Tropsch reaction
olefins
cobalt carbide
promoter effect