The conversion of CO2 over a CoPt/Al2O3 catalyst was investigated. Single-gas adsorption studies indicated that carbon was deposited on the catalyst by exposure to both CO2 and CO in the absence of H2 cofeed. When CO2 was preadsorbed followed by H2 flow, methane was produced, as well as traces of C3-C4 hydrocarbons, but no evidence of the reverse water gas shift reaction was found. Use was made of carbon-14-labeled carbon dioxide to track CO2 conversion and selectivity during reaction of syngas mixtures with different ratios of CO, CO2, and H2. Absence of 14C in unconverted CO and the unequal molar concentration of 14C in the products from reaction at 220 °C and 2 MPa provided strong evidence that 14CO2 was not converted by the reverse water gas shift reaction. The antecedence of the carbon from CO2 mattered, and the carbon did not become part of a common carbon pool for hydrocarbon synthesis. Conversion of CO2 proceeded by a pathway separate from CO. Conclusions drawn from this experimental study were employed to determine implications for the industrial application of Co-catalyzed Fischer-Tropsch synthesis.
|Number of pages
|Industrial and Engineering Chemistry Research
|Published - Feb 4 2015
Bibliographical notePublisher Copyright:
© 2015 American Chemical Society.
ASJC Scopus subject areas
- Chemistry (all)
- Chemical Engineering (all)
- Industrial and Manufacturing Engineering