(120a) Synthesis Gas Conversion to Higher Alcohols On Copper

Higher alcohols have received considerable interest as alternatives to non-renewable, petroleum resources due to their versatility; higher alcohols have applications as fuel additives and alternative feedstocks for producing a variety of petroleum-derived chemicals.¹ Cu-based modified methanol synthesis catalysts have shown promise in experiments as inexpensive catalysts for synthesizing higher alcohols from synthesis gas, a combination of carbon monoxide (CO) and hydrogen (H₂).^2-3 Syngas is a product in coal and biomass gasification and steam reforming of methane, the main component of abundant natural gas. The addition of alkali to Cu-based methanol synthesis catalysts promotes the formation of higher alcohols from CO and H₂.⁴ In order for the large scale commercialization of syngas to higher alcohol conversion processes to become economically feasible the yield and selectivity to higher alcohols must be enhanced. Reaching that goal requires a fundamental understanding of the reaction mechanism for the underlying surface chemistry. In this study, first principles electronic structure calculations based on periodic, self-consistent, density functional theory (DFT) are utilized to gain fundamental insights into kinetically important elementary steps in the synthesis of higher alcohols from CO and H₂ on K-promoted Cu catalysts.

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