Kinetic investigation of dry reforming of methane reaction over Ni–Rh/ZrO2–Al2O3 catalyst using Langmuir-Freundlich isotherm.

The study involved conducting kinetic measurements for the dry reforming of methane (DRM) over a Ni–Rh/Al 2 O 3 (85%)-ZrO 2 (15%) catalyst under a wide range of operating conditions (temperature: 500–900 °C, total flow rate of the inlet feed: 50–100 mL/min). The support material was prepared using the sol-gel method, followed by impregnation of Ni–Rh catalyst on the incipient wetness of the Al 2 O 3 –ZrO 2 support. The calcined, reduced and spent samples were characterized by X-ray diffraction (XRD), thermal gravimetric analysis (TGA), inductively coupled plasma atomic emission spectrometer (ICP-AES), N 2 adsorption/desorption and CHNS analyzer, and tested for activity, yield and stability in DRM reaction. Furthermore, kinetic behavior of Ni–Rh/Al 2 O 3 –ZrO 2 catalyst in DRM process was investigated by assuming DRM and reverse water-gas shift (RWGS) reactions take place on two kinds of different active sites. Experimental data were fitted using rate expressions based on the Langmuir-Freundlich (LF) isotherm for DRM and RWGS reactions. The activation energy for the DRM reaction was optimized at 43.62 kJ/mol, falling within the reported literature range of 24.73–108.9 kJ/mol. Statistical indices indicated that the kinetic model accurately predicted CO 2 conversion compared to other responses, with an error of 12.054%. The computed and experimental trends for CH 4 and CO 2 conversions, H 2 and Co yield in terms of temperature were similar with each other and the difference between the calculated and experimental trends was lower for conversions compared to yields. • Kinetic of DRM process was assessed utilizing a LF approach. • Kinetic model predict well experimental CO 2 conversion than other responses. • The error of the kinetic model was determined to be 12.054%. • DRM reaction activation energy aligning well with existing literature reports. [ABSTRACT FROM AUTHOR]