Arbeláez Perez Oscar Felipe, Bustamante Londoño Felipe, Villa Holguin Aída Luz, Ardila A Alba N, Fuentes Gustavo A
Grupo de investigación Termomec, Facultad de Ingeniería, Universidad Cooperativa de Colombia, Calle 50 No. 40-74 - Bloque A - Piso 4, Medellín, Colombia.
Environmental Catalysis Research Group, Chemical Engineering Department, School of Engineering, Universidad de Antioquia, Calle 70 No. 52-21, Medellín, Colombia.
Sci Rep. 2024 Jul 19;14(1):16667. doi: 10.1038/s41598-024-59070-y.
Monometallic and bimetallic Cu:Ni catalysts with different Cu:Ni molar ratios (3:1, 2:1, 1:1, 1:2, 1:3) were synthesized by wetness impregnation on activated carbon and characterized by TPR (temperature programmed reduction), XRD (X-ray diffraction) and XPS (X-ray photoelectron spectroscopy). The synthesized catalysts were evaluated in the gas phase production of diethyl carbonate from ethanol and carbon dioxide. The largest catalytic activity was obtained over the bimetallic catalyst with a Cu:Ni molar ratio of 3:1. Its improved activity was attributed to the formation of a Cu-Ni alloy on the surface of the catalyst, evidenced by XPS and in agreement with a previous assignment based on Vegard law and TPR analysis. During the reaction rate experiments, it observed the presence of a maximum of the reaction rate as a function of temperature, a tendency also reported for other carbon dioxide-alcohol reactions. It showed that the reaction rate-temperature data can be adjusted with a reversible rate equation. The initial rate as a function of reactant partial pressure data was satisfactorily adjusted using the forward power law rate equation and it was found that the reaction rate is first order in CO and second order in ethanol.
通过在活性炭上进行湿浸渍法合成了具有不同铜镍摩尔比（3:1、2:1、1:1、1:2、1:3）的单金属和双金属铜镍催化剂，并通过程序升温还原（TPR）、X射线衍射（XRD）和X射线光电子能谱（XPS）对其进行了表征。在由乙醇和二氧化碳气相生产碳酸二乙酯的反应中对合成的催化剂进行了评估。在铜镍摩尔比为3:1的双金属催化剂上获得了最大的催化活性。其活性的提高归因于催化剂表面形成了铜镍合金，这一点通过XPS得到了证实，并且与之前基于维加德定律和TPR分析的结论一致。在反应速率实验中，观察到反应速率随温度存在一个最大值，其他二氧化碳-醇类反应也有此趋势。结果表明，反应速率-温度数据可以用一个可逆速率方程进行拟合。用正向幂律速率方程对初始速率随反应物分压的数据进行了满意的拟合，发现反应速率对一氧化碳为一级，对乙醇为二级。
