Response Surface Modeling and Optimization of CO Hydrogenation for Higher Liquid Hydrocarbon Using Cu–Co–Cr + ZSM-5 Bifunctional Catalyst

This paper represents an extensive statistical analysis of the combined effects of operating variables (temperature, pressure, reaction time, and H2/CO flow rate) toward CO-hydrogenation for liquid hydrocarbon which was performed in a fixed bed benchtop reactor system, by means of response surface methodology (RSM). The application of RSM in conjunction with a central composite rotatable design (CCRD) was used for modeling and optimizing the performance of a multivariable FT-synthesis process using bifunctional CuO–CoO–Cr2O3 + ZSM-5 catalyst. The CuO–CoO–Cr2O3 catalyst was synthesized by a coprecipitation method, and its physiochemical characterization was done by using Brunauer–Emmett–Teller, temperature-programmed reduction, thermogravimetric analysis, X-ray diffraction, and transmission electron mocroscopy techniques. Through this work a 50 full factorial (CCRD) experimental design was employed. Maximum CO conversion was predicted and experimentally validated to determine optimum conditions that allow improvement of the performance of the catalyst for a long run time of 120 h. The optimum values of CO conversion, temperature, pressure, and (H2/CO) molar ratio were found to be 64.3%, 310 ± 4 °C, 33–36 bar, and 1.0, respectively.