Active Fischer-Tropsch synthesis Fe-Cu-K/SiO 2 catalysts prepared by autocombustion method without a reduction step

Effective Inclusion of ZnMg in a Fe-Based/HZSM-5-Integrated Catalyst for the Direct Synthesis of Aromatics from Syngas

“…34 However, an excessively high degree of carbonization also promotes the surface carbon deposition, covering a large number of active sites by carbon deposits, that accelerates the deactivation of the catalyst. 35,36 While the addition of Zn, on the other hand, is conducive to the formation of spinel ferrite species (ZnFe 2 O 4 ) that can significantly improve the reaction activity of low-carbon olefins to aromatics (to be discussed). 37 Mg also enables a strong interaction of Fe−Mg and facilitates the reduction and carbonization behavior that induces the chain growth reaction and thus increases the overall aromatics selectivity.…”

Cu-Promoted Iron Catalysts Supported on Nanorod-Structured Mn-Ce Mixed Oxides for Higher Alcohol Synthesis from Syngas

“…The slight reduction peak at about 340 • C corresponds to the surface oxygen reduction of cerium oxide from CeO 2 species to Ce 2 O 3 species [17], indicating the transformation of Ce species during the reduction procedure which is in accordance with the results of XRD. The peaks at about 550 • C could be ascribed to the reduction of iron oxide to metal iron (Fe 2 O 3 to Fe 3 O 4 , Fe 3 O 4 to FeO and FeO to Fe) [11,18,19]. The iron and copper oxide species were probably formed in the process of centrifugation and passivation, oxidized from metal nanoparticles by air.…”

Effect of the nickel impregnation method on clay supports in the hydroconversion reaction of n-decane

“…35–37 Auto-combustion methods involve an oxide-reduction reaction between a fuel such as glycine and an oxidant (generally nitrates) that react exothermically when they reach ignition. 36–38 However, obtaining bifunctional catalysts by means of these auto-combustion processes has not been sufficiently studied and there is only one report related to this system where active catalysts are achieved in the hydroconversion reaction. 39…”

“…33,34 However, in the search for new synthesis methods that allow for better control of particle size, metallic dispersion, distance between metallic and acid sites and larger surface areas, auto-combustion (which requires an external heat source) and Microwave-assisted auto-combustion (where the heat required for ignition is generated from inside the solid) appear as interesting, versatile, simple and accessible methods for the preparation of said solids in short times and at low costs, generating materials with high surface areas, small particle sizes, high crystallinity and purity of the metallic phases, resistance to sintering and greater access to active sites. [35][36][37] Auto-combustion methods involve an oxidereduction reaction between a fuel such as glycine and an oxidant (generally nitrates) that react exothermically when they reach ignition. [36][37][38] However, obtaining bifunctional catalysts by means of these auto-combustion processes has not been sufficiently studied and there is only one report related to this system where active catalysts are achieved in the hydroconversion reaction.…”

“…[35][36][37] Auto-combustion methods involve an oxidereduction reaction between a fuel such as glycine and an oxidant (generally nitrates) that react exothermically when they reach ignition. [36][37][38] However, obtaining bifunctional catalysts by means of these auto-combustion processes has not been sufficiently studied and there is only one report related to this system where active catalysts are achieved in the hydroconversion reaction. 39 In this context and in order to evaluate the effect of the method of metal incorporation (Ni) in properties such as metallic dispersion and metal-support interaction, in this work three synthesis routes are proposed, i) auto-combustion, ii) microwave assisted auto-combustion and iii) wet impregnation, for the supported metallic phase, while the acid function is modulated based on the support using different clays: a bentonite and a vermiculite (clays type 2 : 1, two layers of silicon tetrahedra per one layer of aluminum octahedra), 40 whose fundamental difference is their interlaminar charge (bentonite has a lower charge compared to vermiculite) 41 and a halloysite (clay 1 : 1, has a layer of silicon tetrahedra for a layer of aluminum octahedra) which has the particularity of forming nanotubes with the silicon groups on the exterior surface and the aluminum groups on the interior surface of the nanotubes.…”