Back to Search
Start Over
Effect of NH3 Alkalization and MgO Promotion on the Performance of Ni/SBA-15 Catalyst in Combined Steam and Carbon Dioxide Reforming of Methane.
- Source :
- Journal of Nanomaterials; 5/17/2021, p1-14, 14p
- Publication Year :
- 2021
-
Abstract
- In this work, 31.4 wt.% Ni/SBA-15 (Ni/SBA-15) nonpromoted and alkalized with ammonia solution and by MgO promoter catalysts were prepared and used for combined steam and CO<subscript>2</subscript> reforming of CH<subscript>4</subscript> (bireforming). Effect of concentration of ammonia solution (NH<subscript>3(aq)</subscript>) (10–25 vol.%) and Mg content (3–12 wt.%) on the properties of the Ni/SBA-15 catalysts was investigated by low-angle and powder X-ray diffraction (XRD), N<subscript>2</subscript>-BET isothermal adsorption, SEM, TEM, EDS mapping, H<subscript>2</subscript>-TPR, and CO<subscript>2</subscript>-TPD methods. The performance of the catalysts in bireforming was assessed in the temperature range of 550–800°C. The enhancement of dispersion of NiO particles, reducibility, and basicity of alkalized Ni/SBA-15 catalysts were responsible for improving the catalytic performance of this catalyst. The results revealed that the Ni/SBA-15 treated with 15-25% NH<subscript>3(aq)</subscript> solution and promoted with 3-9% Mg exhibited high activity for CH<subscript>4</subscript> conversion. Meanwhile, Ni6Mg/SBA-15 showed the highest CO<subscript>2</subscript> conversion. Among tested catalysts, Ni/SBA-15-20NH<subscript>3</subscript> and Ni9Mg/SBA-15 samples had an almost equal activity with a CH<subscript>4</subscript> conversion of nearly 97% and a CO<subscript>2</subscript> conversion of about 84% at 700°C thanks to its moderate affinity with both CO<subscript>2</subscript> and CH<subscript>4</subscript>. However, the H<subscript>2</subscript>/CO ratio of the product mixture remained at 2.02 on the Ni/SBA-15-20NH<subscript>3</subscript> catalyst and almost 1 on the Ni9Mg/SBA-15 sample. These results might be related to the fact that the alkalization of the Ni/SBA-15 catalyst by NH<subscript>3(aq)</subscript> solution had an advantage over using MgO because side reactions were unlikely to occur. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 16874110
- Database :
- Complementary Index
- Journal :
- Journal of Nanomaterials
- Publication Type :
- Academic Journal
- Accession number :
- 150316311
- Full Text :
- https://doi.org/10.1155/2021/5570866