Study on CaO-promoted Co/AC catalysts for synthesis of higher alcohols from syngas

Effects of impregnation strategy on structure and performance of bimetallic CoFe/AC catalysts for higher alcohols synthesis from syngas

“…This suggested that the structure of the active sites changed during the CO hydrogenation reaction. This observation was in agreement with our previous results in which Co 2 C species was detected over the Ca or La promoted the Co/AC catalysts [14,25]. It is preferred that not only the dual active of metallic Co and Co 2 C but also the Co-Fe alloy may be responsible for the synthesis of alcohols in our catalysts.…”

“…Table 2 also shows the alcohols distributions of the monometallic and bimetallic catalysts. The main alcohols products for all of the catalysts contained linear alcohols fell in the range of C 1 to C 18 , which was same as our previous results [14,25], but was different from the conclusion of other groups' reports [30][31][32] with the C 1 to C 5 alcohols as products. In the case of the bimetallic CoFe/AC catalysts, the fraction of C 2 -C 5 alcohols reached ca.…”

“…These observations confirmed that the Co 2 C species were formed in the bimetallic catalysts during the CO hydrogenation, as shown by XRD results previously. Based on the previous investigations of our group [14,[25][26][27] and other researchers [46,47] as well as the result of this work, the formation of Co 2 C during the reaction seems to be pivotal for the synthesis of alcohols over the activated carbon supported bimetallic catalysts.…”

Role of Co2C in ZnO‐promoted Co Catalysts for Alcohol Synthesis from Syngas

“…Prior work has associated the Co 2 C phase both with promoting higher alcohol synthesis,,, and with methane selectivity during CO hydrogenation . We found experimentally that Co 2 C is selective toward methane without Zn and more selective towards alcohols with Zn present (Figure and Table ).…”

“…[23] The data in Figure 6 reveal that the presence of Zn on Co catalysts promotes the formation of Co 2 C under syngas reaction conditions. Similar to Zn in this work, the addition of promoters such as Na [8a,24] and CaO [25] are also known to promote the formation of Co 2 C. To understand the mechanism by which Zn promotes Co 2 C formation, we first look to these other systems for inspiration. In the case of Na, one hypothesis is that Na lowers the barrier for CO dissociation, resulting in carbide formation.…”