Effect of Support on Selective Oxidation of Ethyl Lactate to Ethyl Pyruvate over Supported Silver Catalyst
YANG Jingfeng1, HUANG Long1, CHEN Jianhua2, YI Yufeng1, WANG Xincheng1
1. Beijing Key Laboratory of Fuels Cleaning and Advanced Catalytic Emission Reduction Technology, College of New Materials and Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China;
2. Beijing Fleming Technology Company Limited, Beijing 102699, China
Abstract：In order to improve the performance of electrolytic silver catalyst for the selective oxidation of ethyl lactate to ethyl pyruvate, the supported silver-based catalysts were prepared using SiO2, α-Al2O3 and γ-Al2O3 as carriers. The effects of carrier type, loading and calcination temperature on the reaction were systematically investigated. X-ray diffraction (XRD), UV-Vis diffuse reflectance spectrum (UV-Vis DRS) and H2 temperature programmed desorption (H2-TPR) were used to characterize the loaded silver-based catalysts. It was demonstrated that the free Ag+ ions and the positively charged silver cluster of Agnδ+ were the active species of the action. The optimal catalyst with better performance was obtained when carrier type was α-Al2O3, the loading of Ag was 7.8% mass fraction and calcination temperature was 600 ℃. The conversion of ethyl lactate was 96.8% and the selectivity of ethyl pyruvate reached 90.7% under the conditions of the reaction temperature being 340 ℃, molar ratio of oxygen to ester being 1.4 and liquid hourly space velocity (LHSV) being 0.6 h-1. After 100 h of reaction, the catalyst still had high activity and could be regenerated by in-situ carbon burning, which showed a good industrial application prospect.
YANG Jingfeng,HUANG Long,CHEN Jianhua et al. Effect of Support on Selective Oxidation of Ethyl Lactate to Ethyl Pyruvate over Supported Silver Catalyst[J]. Chemical Reaction Engineering and Technology, 2022, 38(5): 402-412.
