Synthesis of Mixed Alcohols from Syngas over Cs-modified Cu/Ce_1−<i>x</i>Zr_<i>x</i>O₂ Catalysts

Abstract

Cu/Ce1-xZrxO2 (x 0-1) was prepared by a coprecipitation-decomposition method using NH3 ・H2O as precipitant (to avoid residues of alkali metals), followed by a boiling process to eliminate NH3 and decompose [Cu(NH3)4] 2 complex. Then Cs was introduced to Cu/Ce1-xZrxO2 by the impregnation method. The prepared CsCu/Ce1-xZrxO2 catalysts (Cs: 1.0 wt%; Cu: 20 wt%) were used to catalyze the synthesis of mixed alcohols in a high-pressure fixed-bed flow reactor under reaction conditions of T 573 K, P 3 MPa, H2/CO 2/1, and GHSV 2400 h -1 . CsCu/CeO2 showed higher CO conversion than the industrial catalyst CsCu/ZnO due to the reducibility of the CeO2 support. Moreover, the STY of higher alcohols over CsCu/CeO2 was much higher than that over CsCu/ZnO due to the oxygen storage capacity of the CeO2-based compounds. Introduction of Zr 4 ions into CeO2 lattices increased the reducibility and the oxygen storage capacity of the CeO2-based compounds, so the STY of higher alcohols over CsCu/Ce0.8Zr0.2O2 was larger than that over CsCu/CeO2. CO conversion increased but selectivity for methanol decreased with higher reaction temperature over CsCu/Ce0.8Zr0.2O2. The selectivity for higher alcohols was maximum at 573 K over CsCu/Ce0.8Zr0.2O2. Both CO conversion and selectivity for higher alcohols increased with higher reaction pressure over CsCu/Ce0.8Zr0.2O2 for the synthesis of mixed alcohols from syngas.

Synthesis of higher alcohols over highly dispersed Cu–Fe based catalysts derived from layered double hydroxides

“…Till now, various types of catalysts have been reported for use in HAS from syngas, such as alkali promoted Cu/ZnO [6][7][8][9], Cu-modified F-T catalysts [10][11][12][13],…”

Effect of secondary additives (Li, Mn) in Fe-promoted Rh/TiO2 catalysts for the synthesis of ethanol from syngas

“…The catalysts for the synthesis of ethanol from syngas can be classified into four categories: (a) Rh-based catalysts [3][4][5][6], (b) modified methanol synthesis catalysts [7,8], (c) modified Fisher-Tropsch catalysts [9,10], and (d) modified Mo-based catalysts [11,12]. Among various catalysts, Rh-based catalysts have the highest selectivity for C 2?…”

Efficient One‐Pot Synthesis of Higher Alcohols from Syngas Catalyzed by Iron Nitrides

“…Several catalyst systems have been developed for HAS till now. In particular, MoS 2 ‐based bimetallic catalysts, such as NiMoS 2 and CoMoS 2 , are widely studied for their high activity and selectivity; however, rigorous operating conditions and sulfur loss hinder their industrial applications . For a modified Cu‐based methanol synthesis catalyst, the promotion of alkalis enhances the C−C and C−O coupling; however, methanol still dominates the product spectrum.…”