Preparation of confined Ru-iongel catalysts and their application for a low temperature water–gas shift reaction

Abstract

In this study, a series of iongel catalysts were prepared and studied for the low temperature water–gas shift (WGS) reaction. Compared to the supported ionic liquid (IL) phase catalysts, Ru-iongel catalysts showed better WGS activity and stability. This was mainly because of the strong interaction between the IL and the silica support by the hydrogen bonds in the iongel catalysts. The IL loading and structure both had a remarkable effect on the catalyst's texture, and thus, affected the catalytic activity. It was found that the activity of iongel catalysts increased with the increase of the IL loading and the iongel catalysts with larger anions showed higher catalyst activity over the WGS reaction. The iongel catalysts showed certain activity over the WGS reaction in the temperature range from 120 °C to 200 °C, and the highest turnover frequency (66.7 h⁻¹) was obtained at 160 °C over 2%Ru/30%[BDMIM]BF₄@SiO₂ catalyst. Through the control experiments and Fourier-transform infrared spectroscopy, a ruthenium carbonyl complex was shown to be the active component.