Effect of reaction conditions on supercritical hexanes mediated higher alcohol synthesis over a CuCoZn catalyst

Abstract

Higher alcohol synthesis (HAS) from syngas over a CuCo based catalyst was investigated under supercritical hexanes conditions. The effects of hexanes/syngas molar ratio, H2/CO molar ratio, and gas hourly space velocity (GHSV) on gas‐phase HAS and supercritical hexanes‐phase HAS (SC‐HAS) were investigated. The CO conversion remained relatively constant with increases in the hexanes/syngas molar ratio, whereas the CH4 selectivity decreased. Higher alcohol productivity was found to increase monotonically with an increase in the hexanes/syngas molar ratio. Productivity of higher alcohols increased with an increase in the H2/CO ratio under the gas‐phase conditions. An opposite trend in higher alcohol productivity with H2/CO was observed in SC‐HAS. Further experiments were performed using argon as the reaction medium for comparison with the supercritical hexanes medium results. The enhanced higher alcohol productivity observed in this system can be attributed to improved extraction of alcohol products from the catalyst pores under the supercritical conditions. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1786–1796, 2014

Toward the Development and Deployment of Large-Scale Carbon Dioxide Capture and Conversion Processes

“…It should be mentioned that, apart from the aforementioned catalyst modifications, feed composition adjustment, and operating condition changes, reaction medium can also affect the productivity of the higher alcohols. Recent work demonstrates that supercritical hexanes not only enhance the extraction of alcohol products from the catalyst pores to promote the heat/mass transfer but also improve the selectivity and productivity of higher alcohols …”

“…Recent work demonstrates that supercritical hexanes not only enhance the extraction of alcohol products from the catalyst pores to promote the heat/mass transfer but also improve the selectivity and productivity of higher alcohols. 204 Challenge. Studies of catalysts for higher alcohol synthesis have achieved significant improvements.…”

Selective Conversion of Syngas into Higher Alcohols via a Reaction-Coupling Strategy on Multifunctional Relay Catalysts

“…Higher alcohols containing beyond two carbon atoms, especially ethanol, can be applied extensively as chemical intermediates, solvents, and fuel additives. − Syngas (CO and H 2 ) chemistry has attracted considerable interest due to the increasing demand for the use of nonpetroleum resources for the production of C 2+ chemicals. The key process for the production of C 2+ compounds via syngas conversion is the activation of syngas and control of C–C coupling while overhydrogenation and methane formation are suppressed.…”

Investigation of Supercritical Isooctane as a Reaction Medium in the Conversion of Methanol to Hydrocarbons over H-ZSM-5

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