Effects of glycols on Fischer–Tropsch synthesis activity and coordination structure of Co species in Co/SiO2: Mechanism for enhanced dispersion of Co0 nanoparticles

Enhancing the Fischer–Tropsch Synthesis Activity of Co-based Catalysts by Adding ZrO x to the SiO2 Support and Chelating Ligands to the Co-precursor

“…In our previous work [19][20][21][22][23], we found that the chelateor glycol-assisted catalysts with Co content of 20 mass% also exhibited higher FTS activity than catalysts prepared without using these organic additives. The effects of combination of the organic additives and ZrO x modification on the activity of the catalysts with higher Co content of 20 mass% were also investigated.…”

“…and polymerlike compounds derived from the chelating agents or glycols during calcination [23]. On the other hand, in situ DRIFTS study on Co (20)/ZrO x (Y)/SiO 2 suggested that interaction between Co and Zr-OH species was formed in the ZrO x -modified catalyst prepared by the LDP method [25].…”

“…3. High temperature H 2 reduction had minor influence on the catalysts prepared in the absence of ZrO x , i.e., Co (20) Since Co/SiO 2 catalysts with enhanced activity could be prepared using other glycols such as DEG and TEG [22,23], the doubly promoted catalysts were also prepared using these glycols. Their FTS activity was investigated under the same reaction conditions after H 2 reduction at 773 K. As depicted in Fig.…”

“…. In successive studies [22,23], it was also demonstrated that glycols with weak affinity to Co 2? such as ethylene glycol (EG), diethylene glycol (DEG), or triethylene glycol (TEG) enhanced dispersion of Co 0 as well without loss of the high reducibility of Co.…”

“…Details of the stepwise impregnation method can be found elsewhere [19,21]. For the catalyst prepared using glycols, the co-impregnation method was used regardless the Co content of the catalysts [22,23]. The catalysts thus prepared were denoted as Co(X)-chelate(Y)/SiO 2 (co-impregnation) Co(X)-chelate(Y)/ZrO x /SiO 2 (stepwise impregnation) and Co(X)-Gly(Y)/ZrO x /SiO 2 in this paper, where X and Y denote Co content (as metallic Co) and molar ratio of the organic additives to Co 2?…”