Dysprosium promotion on Co/Al2O3 catalysts towards enhanced hydrogen generation from methane dry reforming. (15th September 2022)

• Record Type: Journal Article
• Authors: Cao, Anh Ngoc T.; Pham, Cham Q.; Nguyen, Tung M.; Van Tran, Thuan; Phuong, Pham T.T.; Vo, Dai-Viet N.
• Is Part Of: Fuel. Volume 324:Part C(2022)
• Publication Date: 2022-09-15
• Subjects: Hydrogen -- Syngas -- Methane dry reforming -- Cobalt catalyst -- Dysprosium promoter; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2022.124818
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: Dy addition significantly enhanced the basicity of Co/Al2 O3 catalyst. 0.3 wt%Dy was the best loading for activity and deposited carbon mitigation. Dy promotion mitigated carbon deposition because of its redox cycling character. H2 /CO ratios varied within 0.70–0.86 at 973 K. Abstract: Dysprosium (Dy) promoted Co/Al2 O3 catalysts with different Dy loadings (0-3 wt%) were synthesized via an impregnation approach for methane dry reforming. Promoter addition enhanced the basicity of catalysts owing to the basic attribute of Dy2 O3 . Co3 O4 crystallite sizes were reduced from 8.15 to 6.68 nm with 0.1–0.3 wt%Dy promotion due to the diluting effect, resulting in higher metal dispersion. Particularly, at 973 K, 0.3 wt%Dy appeared as the best promoter loading and achieved the highest CH4 conversion, as well as H2 and CO yields of the corresponding 79.4%, 65.8% and 89.2% because of growing basic site density and the enhancing number of Co active sites. The temperature-programmed oxidation analyses also revealed that 0.3%Dy-10%Co/Al2 O3 suppressed carbonaceous deposition from 12.84% to 7.76% since the extra oxygen mobility and redox cycling of Dy2 O3 could effectively oxidize surface carbonaceous species to CO and H2 .