钙钛矿型La2NiB'O6催化剂Ni和B'位点的协同效应及其对二氧化碳甲烷化性能的影响
Synergistic effect of Ni and B'Sites on Perovskite type La2NiB'O6 catalyst and its effect on catalytic performance for carbon dioxide methanation
钟读乐 1刘磊 2李婉婷 2刘立伟 2南军 1李奇2
作者信息
- 1. 中海油天津化工研究设计院有限公司,天津 300131
- 2. 中国科学院苏州纳米技术与纳米仿生研究所,江苏 苏州 215123
- 折叠
摘要
钙钛矿型金属氧化物由于高的可逆储氧能力和结构稳定的特点,在催化领域被广泛应用.本文研究了钙钛矿型金属氧化物对于CO2甲烷化的催化活性,通过溶胶凝胶法制备了 LaNiO3催化剂,同时用不同的元素B'(B'=Co,Mn,Fe)对Ni进行掺杂得到La2NiB'O6双钙钛矿,通过测试催化能力以研究不同金属间协同作用对催化效果的影响,利用XRD,BET,SEM和H2-TPR等方法对制备的催化剂进行了 一系列表征.结果显示,第二金属元素的加入没有改变原有的结构,将前驱体进行简单还原后,La2NiB'O6催化剂具有高的氧空位、较好的还原性、优异的Ni分散性,它取决于Ni-B'离子之间的协同作用.其中,La2NiCoO6催化剂在400 ℃表现出最佳的催化性能,转化率达91.3％,这归因于Co掺杂形成的双金属合金以及在3种催化剂中具有更高的氧空位,更好的还原性能和对CO2更强的吸附性能,提供了更多的反应位点,从而增强了 La2NiCoO6催化剂对CO2甲烷化反应的催化活性.
Abstract
In this paper,the catalytic activity of perovskite type metal oxides for CO2 methanation was in-vestigated.LaNiO3 catalyst was prepared by sol-gel method,and La2NiB'O6 perovskite was obtained by doping Ni with different elements B'(B'=Co,Mn,Fe).The catalytic ability of different catalysts was tested to study the synergistic effect between different metals.Prepared catalysts were characterized using XRD,BET,SEM and H2-TPR.The results indicate that the original structure remained unchanged de-spite the introduction of a second metal element.Reducing the precursor in a hydrogen atmosphere resul-ted in the formation of La2O3 from the A site of La,and the reduction of the B site to the corresponding metal ions.Due to the synergistic effect between different Ni-B'ions,the La2NiB'O6 catalysts showed differences in oxygen vacancies,reducibility,and dispersion.Among them,the Ni-Fe ions increased the o-verall reduction resistance of the catalysts due to the high temperature stability of Fe.Conversely,The La2NiCoO6 catalysts showed excellent performance in oxygen vacancy,reducibility and dispersibility,which enabled the catalysts to provide more reactive sites for the reaction and enhanced the adsorption per-formance of CO2,and thus strengthened the catalytic activity of La2NiCoO6 catalysts in the methanation reaction of CO2.In performance test,La2NiCoO6 achieved the highest conversion and selectivity,showing the best catalytic performance at 400 ℃,with a conversion of 91.3％.
关键词
双钙钬矿型氧化物/CO2甲烷化反应/B位掺杂/协同效应Key words
bimetallic oxides/CO2 methanation reaction/synergistic effect引用本文复制引用
基金项目
CNOOC joint project(E3491501)
出版年
2024
NETL
NSTL
万方数据