Selective CO methanation over CeO$_{2}$--ZrO$_{2}$-composed NiO and Co$_{3}$O$_{4}$ catalysts

Abstract

CeO 2-ZrO 2-composed NiO and Co 3 O 4 catalysts were prepared by 3 different methods. Both CO methanation and selective CO methanation were carried out. All catalysts were prepared by (1) co-precipitation, (2) surfactantassisted co-precipitation, and (3) surfactant-assisted co-precipitation with ultrasound mixing methods. Catalysts were characterized by using N 2 physisorption, XRD, SEM, TEM, and TPR-H 2 techniques. The highest surface area value, uniform pore size distribution, and pores having small diameters were observed for the catalysts prepared by using the surfactant and ultrasound. The NiO/CeO 2 /ZrO 2 prepared by the surfactant-assisted co-precipitation was the most active catalyst for CO methanation. It gave 50% CO conversion to CH 4 at 150 • C and all CO was converted to CH 4 after T > 225 • C. Moreover, 22.3% CH 4 was formed and the CO level decreased below 100 ppm at 200 • C during the selective CO methanation activity test over this catalyst.

Selective CO methanation over NiO--Al$_{2}$O$_{3}$--ZrO$_{2}$ and Co$_{3}$O$_{4}$--Al$_{2}$O$_{3}$--ZrO$_{2}$ catalysts

“…After 300 • C methanation activity decreased because of the reverse water gas shift reaction. The CO level decreased under 100 ppm at 200 • C. The method that we used is given by Derekaya et al 50 Characteristic properties were determined by different techniques. Finally, methanation studies were carried out to investigate the effect of the catalyst preparation methods on activity.…”

“…25,26 The aim of the present study was to develop a catalyst that shows high activity for CO methanation and selective CO methanation reactions. For this aim, two different catalysts were prepared as follows: 50…”