Preparation and evaluation of highly dispersed HHSS supported Cu-Fe bimetallic catalysts for higher alcohols synthesis from syngas

Porous carriers play an important role in the catalytic transformation of syngas into higher alcohols, which promises higher sustainability in C1 chemistry. In this work, a series of hierarchical hollow silica spheres (HHSS) supported Cu-Fe bimetal catalysts were successfully prepared through ultrasonic-assisted impregnation for higher alcohols synthesis from syngas. Structural characterization results indicate that the hierarchical hollow structure of HHSS support can be maintained and the Cu-Fe bimetallic nanoparticles are highly dispersed on HHSS surface. The catalytic performances of samples in the test of CO hydrogenation for higher alcohols synthesis were investigated. The results revealed that the conversion rate of CO and the selectivity of C 2+ OH alcohol increased first and then decreased with the decrease of the amount of Cu content in the Cu x Fe y @HHSS catalyst. The highest CO conversion, alcohol selectivity and STY ROH over Cu-Fe@HHSS catalyst are 65.1 %, 46.6 %, and 118.1 gkg −1 h −1 , respectively. It was found that a large number of CuFe 2 O 4 were formed in Cu-Fe@HHSS catalyst and also confirmed that the CuFe 2 O 4 spinel and CuO-CuFe 2 O 4 were converted to Cu-Fe 5 C 2 composite in the spent Cu-Fe@HHSS catalyst, which can enhance the synergy between Cu-Fe bimetals. Furthermore, copper and iron are highly dispersed on HHSS after the reaction, which enhances the structural stability of the catalyst. Based on the development and utilization of low-cost catalysts and the production of clean liquid fuels, HHSS has a great prospect of catalyst support in the energy field.