Enhanced synergy between Cu 0 and Cu + on nickel doped copper catalyst for gaseous acetic acid hydrogenation
- PDF / 1,947,492 Bytes
- 13 Pages / 595.276 x 785.197 pts Page_size
- 115 Downloads / 210 Views
RESEARCH ARTICLE
Enhanced synergy between Cu0 and Cu+ on nickel doped copper catalyst for gaseous acetic acid hydrogenation Jingwei Zhang, Lingxin Kong, Yao Chen, Huijiang Huang, Huanhuan Zhang, Yaqi Yao, Yuxi Xu, Yan Xu, Shengping Wang, Xinbin Ma, Yujun Zhao (✉)
Key Laboratory for Green Chemical Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
© Higher Education Press 2020
Abstract As the substitution of common noble catalysts in the hydrogenation of carboxylic acid, a highly effective Cu-Ni/SiO2 catalyst was prepared by a novel stepwise ammonia evaporation method. Its performance in the gasphase hydrogenation of acetic acid was further examined. With the introduction of Ni dopant, more stable Cuδ+ sites, which can adsorb more acetic acid, were formed due to the electron transfer from Cu to Ni. This makes more Cu0 sites available for hydrogen adsorption, which was suggested as the rate-determining step in acetic acid hydrogenation. A conversion of 99.6% was successfully achieved on this new Cu/SiO2-0.5Ni catalyst, accompanied by the ethanol selectivity of 90%. The incorporation of nickel between copper nanoparticles enhances the synergistic effect between Cu0 and Cu +. It also helps mitigate the aggregation of copper nanoparticles due to the Ostwald ripening effect induced by acetic acid and enhance the stability of copper catalyst in the conversion of carboxylic acid. Keywords carboxylic acid, hydrogenation, copper, nickel, stability
1
Introduction
Energy becomes one of the big threats to the world because of the gradual depletion of fossil energy. Biomass is a promising alternative energy source due to its renewable nature and quantitative supply [1,2]. Pyrolysis technology is normally used to convert biomass into liquid bio-oil, chemicals, or other products. During this procedure, a large Received April 15, 2020; accepted July 2, 2020 E-mail: [email protected]
quantity of carboxylic acid is generated [3,4]. Carboxylic acids or esters derived from biomass are usually utilized to produce biodiesel or other biofuel [5‒7]. In addition, residual carboxylic acids in biofuel can cause undesired side reactions such as polymerization or esterification, producing unwanted large molecules [3,8] or disturbing the reaction temperature and product selectivity [9]. Therefore, it is necessary to convert these carboxylic acids to valuable chemical products or liquid fuel for better utilization of biomass. Among many carboxylic acid conversion processes, selective hydrogenation to alcohol is considered as an effective process [4,10,11]. Acetic acid is the most common model compound that is used to develop effective catalysts or study the catalyst mechanism for the carboxylic acid hydrogenation. Most catalysts used in selective hydrogenation of acetic acid come from noble metals of group VIII elements. These catalysts were mainly comprised of noble metals supported on metal ox
Data Loading...
