Effect of Surfactant-Induced Modifications on CuCoMn Catalysts for Higher Alcohol Synthesis

A series of surfactant-modi ed CuCoMn-based catalysts were prepared for higher alco-hol synthesis from biomass-based syngas. Three typical surfactants, cetyltrimethylammo-nium bromide (CTAB), sodium dodecyl sulfate (SDS) and pluronic P123 triblock copoly-mer (EO₂₀PO₇₀EO₂₀), were employed. Compared to surfactant-free CuCoMn catalyst, CO conversion increased from 17.4% to 29.7% over SDS-modi ed CuCoMn catalyst, and the selectivity of higher alcohols increased from 22.0% to 41.2% over CTAB-modi ed catalyst. Besides, the proportions of higher alcohols in total alcohols increased over all surfactant-modi ed catalysts. The catalysts were characterized by N2 adsorption/desorption, XRD, XPS and IR analysis. The results showed that several more favorable features rendered the CTAB-modi ed CuCoMn catalyst to be suitable for higher alcohol production, such as the larger pore size, better crystallinity of CuCoMnO4 spinel, moderate surface atomic distribu-tion and lower valence of metallic ions. In addition, it was veri ed that CTAB addition at the metal precipitation stage was bene cial to higher alcohol synthesis. Surfactant-induced modi cation provides a promising alternative method for catalyst improvement in synthesis of higher alcohols.