Hydrogen Production by Glycerol Steam Reforming on the Ni/CaO-Al.sub.2O.sub.3 Catalysts: The Study of Synergistic Effect Between CaO and Al.sub.2O.sub.3

• Published in: Catalysis letters 2023-12, Vol.153 (12), p.3698
• Main Authors: Sabokmalek, Saleh, Alavi, Seyed Mehdi, Rezaei, Mehran, Akbari, Ehsan
• Format: Article
• Language: English
• Subjects: Catalysts; Glycerin; Glycerol; Hydrogen; Lime
• ISSN: 1011-372X
• DOI: 10.1007/s10562-022-04247-1

Ni catalysts impregnated on CaO-Al.sub.2O.sub.3 with various Al/Ca molar ratios were synthesized, and employed in the glycerol steam reforming process to investigate the effect of calcium content on the catalyst efficiency. The prepared catalysts were characterized by XRD, BET, H.sub.2-TPR, CO.sub.2-TPD and SEM analyses. According to the preliminary tests, the characteristic features of the catalysts were directly affected by the Al/Ca molar ratio. The specific surface area and total pore volume increased with increasing in Al.sub.2O.sub.3 content. Meanwhile, the higher CaO content increased the catalyst reducibility and also the concentration of basic sites. The sample with Al/Ca of 2 had the best performance with glycerol conversion of 99.4% and H.sub.2 yield of 99.9% at 700 °C. Moreover, the results revealed that the catalyst calcined at 500 °C, and reduced at 700 °C possessed a glycerol conversion of 99.4% and this catalyst was selected as the best sample among the studied catalysts.