Promotion Effect of Lantanum ions on Co/SiO_2 Catalysts Prepared via Solvated Metal Atom Impregnati

• 作 者: 吴世华 张守民 黄维平 李保庆 石娟
• 机 构: Department of Chemistry, NanKai University, Tianjin 300071, China,Department of Chemistry, NanKai U
• 出 处: Journal of Rare Earths
• 发表日期: 2004年03期
• 关键词: octane silica toluene promoted alumina

In order to assess the promotional effects of La~(3+) on CO hydrogenation of Co/SiO_2 catalyst, solvated metal atom impregnation (SMAI) method was used to prepare unpromoted 10% (mass fraction) Co/SiO_2 and a series of La~(3+)-promoted 10% (mass fraction) Co/SiO_2 catalyst with different La/Co atomic ratios (0.1, 0.3, 0.5). X-ray diffraction (XRD), and CO chemisorption measurements show that the cobalt particle size decreases as the La/Co ratios increase. X-ray photoelectron spectrescopy indicates that cobalt is in zero-valent state for all the samples. Catalytic test shows that the catalytic activity of La~(3+)-promoted Co/SiO_2 in CO hydrogenation is higher than that of unpromoted Co/SiO_2, and enhances with the La/Co ratios increase. La~(3+) promotion also causes the enhanced selectivity of Co/SiO_2 catalyst for higher hydrocarbon products.

In order to assess the promotional effects of La ~ (3+) on CO hydrogenation of Co / SiO_2 catalyst, solvated metal atom impregnation (SMAI) method was used to prepare unpromoted 10% (mass fraction) Co / SiO_2 and a series of La X-ray diffraction (XRD), and CO chemisorption measurements show that the cobalt particle size was ~ (3 +) - promoted 10% mass fraction Co / SiO 2 catalyst with different La / Co atomic ratios Catalytic test shows that the catalytic activity of La ~ (3 +) - promoted Co / SiO_2 in CO hydrogenation is higher than that of unpromoted Co / SiO 2, and enhances with the La / Co ratio increase. La ~ (3+) promotion also causes the enhanced selectivity of Co / SiO_2 catalyst for higher hydrocarbon products.