Preparation of Phyllosilicate Catalysts Using Rice Husk as Template for CO2 Hydrogenation
SONG Miaomiao1, GUO Meiting1, CAI Dongren1, ZHAN Guowu1, WANG Yuanpeng2, LI Qingbiao2
1. College of Chemical Engineering, Huaqiao University, Integrated Nanocatalysts Institute (INCI), Xiamen 361021, China;
2. College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
Abstract：Herein, the layered transition metal silicates were prepared by using the rice husk as both silicon source and hard template, and the transition metal ions in the silicate can be in-situ reduced by H2 to prepare transition metal-based catalysts for CO2 hydrogenation reaction. The rice husk and the derived catalysts were systematically characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), nitrogen physical adsorption, X-ray fluorescence spectroscopy (XRF), thermalgravimetric analysis (TGA), H2 temperature-programmed reduction (H2-TPR), and so forth. The results showed that the rice husks indeed provide the silicon source for the growth of phyllosilicate under hydrothermal conditions, while the obtained phyllosilicate retained the hierarchical porous structure of rice husks. CO2-temperature-programmed desorption (CO2-TPD) verified that the alkali metals (K, Ca) in rice husk could self-dope the resultant phyllosilicate and promote the CO2 adsorption capacity of the phyllosilicate. In addition, the prepared transition metal catalysts can effectively catalyze the CO2 hydrogenation, wherein the nickel silicate exhibited the highest catalytic activity. Besides, in-situ diffuse reflection Fourier transform infrared spectroscopy (DRIFTS) was used to explore the intermediates in CO2 hydrogenation over the nickel silicate catalyst. The results showed that formate (HCOO*) was the key species for the production of CO and CH4.
SONG Miaomiao,GUO Meiting,CAI Dongren et al. Preparation of Phyllosilicate Catalysts Using Rice Husk as Template for CO2 Hydrogenation[J]. Chemical Reaction Engineering and Technology, 2022, 38(4): 318-328.
