Selective conversion of syngas to olefins-rich liquid fuels over core-shell FeMn@SiO2 catalysts

High-yield production of liquid fuels in CO2 hydrogenation on a zeolite-free Fe-based catalyst

“…This indicates that KZFe-5.0Co is a promising catalyst for efficiently catalyzing CO 2 into long-chain hydrocarbons with high yield. 35,36 However, for KZFe-2.5Co and KZFe-10.0Co, the peaks ascribed to Fe 3 O 4 disappear, while the peaks corresponding to Co 3 Fe 7 (JCPDS, 48-1817) appear. In contrast, the diffraction intensity of KZFe-5.0Co and KZFe-20.0Co is lower that of KZFe-2.5Co and KZFe-10.0Co, probably due to benign dispersion or the formation of small particles.…”

“…After reaction, for the KZFe catalyst, there exist three main phases, Fe 3 O 4 (JCPDS, 89-3854), ZnO, and Fe 5 C 2 (JCPDS, 20-0509) respectively. 35,36 However, for KZFe–2.5Co and KZFe–10.0Co, the peaks ascribed to Fe 3 O 4 disappear, while the peaks corresponding to Co 3 Fe 7 (JCPDS, 48-1817) appear. In contrast, the diffraction intensity of KZFe–5.0Co and KZFe–20.0Co is lower that of KZFe–2.5Co and KZFe–10.0Co, probably due to benign dispersion or the formation of small particles.…”

Effect of Silica Encapsulation on Cobalt-Based Catalysts for Fischer–Tropsch Synthesis under Different Reaction Conditions

“…The influence of shell thickness or pore length on activity and selectivity has also been reported, since CO diffusion limitations may enhance CH 4 selectivity and chain termination probability, , and H 2 O diffusion limitation may lead to the oxidation of the active sites . Many studies have already reported the application of different nature multicore@shell nanoparticles, ,,− core@shell nanoparticles shaped as nanoplates or cubes, and nanocomposites ,, as catalysts in Fischer–Tropsch synthesis. It is worth mentioning that the use of encapsulated nanoparticles might help the understanding of how the diffusion of the reagents and products affects Fischer–Tropsch synthesis, in particular with the use of concentric spherical single-core@shell structures.…”

“…Core–shell particles are an interesting morphology to hinder sintering, since the encapsulation of the active phase by a coating material allows its protection against agglomeration. ,, The use of cobalt core–shell catalysts in Fischer–Tropsch synthesis has already proved effective in modifying the product distribution in comparison with supported catalysts. , Moreover, the variation of the morphological and textural properties of the encapsulating shell may also influence the reaction activity and selectivity, ,, since changes in the reactants and products diffusion might influence the availability of reactants on the active sites and play a role in the hydrocarbon chain growth mechanisms . In that sense, different diffusion regimes may occur within pores of distinct sizes, such as Knudsen diffusion in mesopores, in which lighter molecules would diffuse faster, and configurational diffusion in micropores, in which steric effects would predominate .…”

Novel polyhedral@SiO2 core–shell catalysts designed for Fischer–Tropsch synthesis

“…12,13 Some works have been reported concerning SiO 2 -encapsulated core-shell catalysts. 3,14,15 Zhang et al prepared Fe@Si catalyst and showed that the stability of iron species against sintering was effectively improved by the SiO 2 shell. 3 Besides, Xu et al showed that the C 5+ selectivity over FeMn@SiO 2 -0.25 was higher than that over FeMn.…”