In掺杂对CuZn催化剂合成气制低碳醇性能影响

Effect of In doping on the performance of CuZn catalyst for synthesis of low carbon alcohol from syngas

中文关键词:  完全液相法  In组分含量  CO2选择性

英文关键词:complete liquid-phase method  In component contents  CO2 selectivity

中文摘要:

      为解决CuZnAl催化剂在合成气（CO和H2）制C2+醇过程中CO2选择性高，总醇选择性低的问题，采用完全液相法制备了不同In组分含量的CuZnIn催化剂（Cat-Inx）。XRD、N2吸/脱附和H2-TPR等表征结果表明，In改变了催化剂表面的Cu晶粒尺寸、还原性质和表面元素组成，与Cu存在较强的相互作用和电荷转移，显著抑制了CO2的生成。Cat-In4具有最好的综合催化性能，在反应48 h时CO转化率18.77%，CO2选择性17.68%，总醇选择性41.94%，C2+醇在总醇中的占比可达76.38%，其中乙醇占总醇63.22%。本研究结果支持In的作用是：稳定关键中间体CHx*，促进C-C键形成，进而推动反应向C2+醇方向进行，显著降低CO2的选择性。

英文摘要:

      To address the high CO2 selectivity and low total alcohol selectivity of CuZnAl catalysts in syngas (CO and H2) conversion to C2+ alcohols, CuZnIn catalysts with varying indium (In) contents (denoted as Cat-Inx) were synthesized via a complete liquid-phase method. Characterization by XRD, N2 adsorption/desorption, and H2 temperature-programmed reduction (H2-TPR) revealed that In incorporation modulated the Cu crystal size, reduction behavior, and surface elemental composition of the catalysts, and had a strong interaction and charge transfer with Cu, significantly suppressing the formation of CO2. The strong Cu-In interaction and charge transfer significantly suppressed CO2 formation. Among the catalysts, Cat-In4 exhibited optimal performance, achieving a CO conversion of 18.77%, CO2 selectivity of 17.68%, and total alcohol selectivity of 41.94% after 48 h of reaction. Notably, C2+ alcohols accounted for 76.38% of the total alcohols, with ethanol contributing 63.22% to the alcohol products. The results of this study support that the role of In is to stabilize the key intermediate CHx* and promote C-C bond formation, which in turn drives the reaction in the direction of C2+ alcohol and significantly reduces the selectivity of CO2.