Influence of Supports on the Catalytic Activity and Coke Resistance of Ni Catalyst in Dry Reforming of Methane

Da Hye Song,Hyo Been Im,Un Ho Jung,Tae Ho Lee,Ki Bong Lee,Kee Young Koo,Young Eun Kim

doi:10.3390/catal12020216

Abstract

The dependence of the catalytic activity and coke resistance of Ni-based catalysts on the support type was investigated in the dry reforming of methane (DRM). Catalysts were prepared using incipient wetness impregnation and analyzed using ICP-OES, BET-BJH, XRD, H2-chemisorption, H2-TPR, and CO2-TPD. DRM was performed at 600–750 °C at 144,000 mL/gcat∙h of GHSV (CH4/CO2/N2 = 1/1/1). Ni/Al2O3 and Ni/MgO catalysts formed NiAl2O4 and NiO-MgO solid solutions, respectively, owing to strong binding between the metal and support. In contrast, MgO-Al2O3 and MgAl2O4 supports suppressed NiAl2O4 and NiO-MgO solid solution formation, due to Mg addition, with high metal dispersions of 4.6 and 6.6%, respectively. In the DRM reaction, the Ni/MgO-Al2O3 and Ni/MgAl2O4 catalysts showed high CH4 conversions of 78.1 and 76.8%, respectively, compared with Ni/Al2O3 and Ni/MgO at 750 °C. A stability test was performed at 600 °C for 20 h. A coke study of the spent catalysts was performed using SEM and TGA. Alkaline-earth metal-containing catalysts Ni/MgO-Al2O3 and Ni/MgAl2O4 with strong CO2 adsorption properties showed 20 wt% reduction in carbon deposition compared to commercial catalysts. Therefore, the support and basic properties of the catalyst significantly influenced the catalyst performance and coke resistance in the DRM.

Highlights

Publisher’s Note: MDPI stays neutralRecently, there has been an increased focus on problems related to climate change and the need for reducing carbon dioxide (CO2 ) emissions
Zanganeh et al reported that the crystallite size increased and the specific surface area decreased with increasing calcination temperature when NiOMgO was calcined at 600–800 ◦ C [22]
This was attributed to the lack of calcination of the MgO-Al2 O3 (LDH) support used for the Ni catalyst preparation, which contained MgO and Al2 O3 in a 30:70

Summary

Introduction

Publisher’s Note: MDPI stays neutralRecently, there has been an increased focus on problems related to climate change and the need for reducing carbon dioxide (CO2 ) emissions. The development of carbon dioxide utilization (CDU) technologies is necessary to reduce CO2 emissions over the long term. Among CDU technologies, the dry reforming of methane (DRM) reaction is an important technique that could be used to reduce the total annual anthropogenic greenhouse gas emissions (multi-GtCO2 /year) [1,2]. The. DRM reaction (Equation (1)) produces the beneficial syngas (H2 + CO) from CH4 and CO2 [4]. The product H2 /CO ratio of the DRM reaction is 1, which renders the produced syngas suitable for the synthesis of methanol and dimethyl ether or Fischer–Tropsch synthesis [5]. The reverse water gas shift (RWGS) reaction (Equation (2)) occurs as a side reaction up to 820 ◦ C under the DRM with regard to jurisdictional claims in published maps and institutional affiliations

Methods

Results

Conclusion