Cobalt-Nickel Catalysts for Selective Hydrogenation of Carbon Dioxide into Ethanol
Cobalt-Nickel Catalysts for Selective Hydrogenation of Carbon Dioxide into Ethanol
复制标题
用于二氧化碳选择性加氢成乙醇的钴镍催化剂
DOI：
10.1021/acscatal.9b04187
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发表时间：
2019
期刊：
影响因子：
12.9
通讯作者：
Xiao Feng-Shou
中科院分区：
文献类型：
--
作者：
Wang Lingxiang;He Shenxian;Wang Liang;Lei Ye;Meng Xiangju;Xiao Feng-Shou
CO2选择性加氢生成有价值的乙醇是通过偶联适当的C1中间体形成C2-含氧化合物来进行的。匹配不同的C1中间体对于该过程至关重要，但难以控制。我们发现，将镍物种引入钴催化剂中可以促进从CO2加氢形成相对稳定的 * CHx中间体，这显著地避免了甲烷化的发生。* CHx物种随后插入到 *HCOO中，这是另一种容易形成的中间体，以产生C2-含氧化合物。优化后的催化剂Co0.52Ni0.48AlOx在200 °C下反应12 h，乙醇收率为15.8 mmol gcat-1，选择性为85.7%，优于贵金属催化剂。
Selective hydrogenation of CO2into valuable ethanol proceeds by the coupling of appropriate C1intermediates to form C2-oxygenates. Matching the different C1intermediates is crucial for this process but is difficult to control. We found that incorporation of nickel species into the cobalt catalyst could boost the formation of relatively stable *CHxintermediate from CO2hydrogenation, which significantly avoids an occurrence of methanation. The *CHxspecies subsequently insert into the *HCOO, another intermediate that is easily formed, to produce C2-oxygenates. Following this pathway, the optimized catalyst, Co0.52Ni0.48AlOx, gives the ethanol yield at 15.8 mmol gcat–1with selectivity at 85.7% in the CO2hydrogenation at 200 °C for 12 h, which even outperforms those of noble metal catalysts.