1,3,5-Benzenetricarboxylic acid assisted synthesis of CuZnAlZr catalysts for CO2 hydrogenation to methanol
CO2 hydrogenation to methanol is one of the important ways to synthesize chemical value-added products,which helps to relieve energy and environmental pressure.CuZnAlZr catalysts for CO2 hydrogenation to methanol were synthesized by co-precipitation method,and the resulting catalysts were characterized by X-ray diffraction(XRD),N2O-H2 titration,N2 adsorption/desorption,H2 temperature programmed reduction(H2-TPR),X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM)and transmission electron microscopy(TEM).And the effects of 1,3,5-benzenetricarboxylic acid(BTC)assisted synthesis on the dispersion of active Cu species in CuZnAlZr catalysts and their catalytic performance were investigated in detail.The results show that after the introduction of BTC into the CuZnAlZr catalysts precursor,the gas products generated by the decomposition in the calcining stage,contributes to the increase of the specific surface area of the catalyst and generates more pore structures,and it also weakens the interaction between Cu and the carrier oxide,which contributes to the dispersion of Cu species.When the amount of BTC introduced into the catalyst is n(BTC)/n(Cu2+)= 1/6,more highly dispersed smaller Cu grains and ZnO crystalline phases existe on the surface of the CuZnAlZr catalysts calcined in air and the enhanced synergy between Cu and ZnO species leds to excellent catalytic performance with CO2 conversion rate and methanol space-time yield up to 27.81%and 278.6 g/(kg·h),respectively.This indicates that the introduction of appropriate amount of BTC in the precursor to assist the synthesis can lead to highly active hydrogenation catalysts with high Cu dispersion and small Cu grains.
国家科技期刊平台
NSTL
万方数据
