A Fast and Efficient Response Surface Approach for the Optimization of the Gas-Phase Hydrogenation of Carbon Dioxide on Nickel-Based Catalysts

In this study, the application of the response surface method was used to determine the best reaction conditions of the gas-phase hydrogenation of carbon dioxide on a commercial nickel-based catalyst. The procedural goals included the choice and tests of the robustness of the statistical method that could improve the achievement of the goal of the process, first of all by reducing the number of necessary experiments. The outcome goal for the process under consideration was the optimization of reaction conditions for mild reaction conditions and the stoichiometric deficiency of hydrogen; these reaction conditions are rarely presented in the literature (despite their potential advantages). Both goals were achieved with a successful result. To find optimal reaction conditions, only 36 experiments were carried out. This is a very good result, taking into account the insufficient information in the literature, which means that it is a difficult task to deduce the region of the highest carbon dioxide conversion. The maximum carbon dioxide conversion was obtained for a temperature of 318 °C and a ratio of molar fluxes of H2 to CO2 equal to 3.5. It should be emphasized that this result was confirmed experimentally.