Alkane metathesis over immobilized pincer-ligated iridium complexes: Effect of support nature

In this work, catalytic alkane metathesis has been evaluated as a suitable approach to upcycle hydrocarbons (polyolefins) at moderate temperatures. To this end, a pincer-ligated iridium complex (dehydrogenation catalyst) has been combined with a rhenium-based (metathesis) catalyst, being the effect of immobilizing the Ir complex over different supports deeply investigated. FTIR spectroscopy has been used to confirm the complex grafting and to elucidate the anchoring site…

Unraveling the Mo/HZSM-5 reduction pre-treatment effect on methane dehydroaromatization reaction

Reduction pre-treatment at different temperatures were performed over Mo/HZSM-5 system before methane dehydroaromatiztion reaction. We have shown the crucial effect of reduction temperature on the final catalytic performance. Outstanding improvement in the aromatics conversion has been attained. Thus, H-2 formation form methane cracking reaction seems to be hindered for pre-treated catalysts. As a consequence, the…

Evidence of new Ni-O-K catalytic sites with superior stability for methane dry reforming

Liquid fuels produced via Fischer-Tropsch synthesis from biomass-derived syngas constitute an attractive and sustainable energy vector for the transportation sector. This study focuses on the role of potassium as a promoter in Ni-based catalysts for reducing coke deposition during catalytic dry reforming. The study provides a new structural link between catalytic performance and physicochemical properties.…

Characterization of Re-Mo/ZSM-5 catalysts: How Re improves the performance of Mo in the methane dehydroaromatization reaction

In this study, the promoting effect of rhenium addition as a co-dopant on Mo/ZSM-5 catalysts system has been analysed. Hence, bimetallic (Re-Mo/ZSM-5) catalysts have been synthesized using a sequential impregnation methodology. The catalytic performance for direct aromatization of methane reaction has been determined and correlated with their physical and chemical state combining multiple characterization techniques.…

IR spectroscopic insights into the coking-resistance effect of potassium on nickel-based catalyst during dry reforming of methane

Dry reforming of methane (DRM) is an effective catalytic route for transforming CO2 and CH4 into valuable syngas and thus potentially attractive for mitigating the emission of environmental harmful gases. Therefore, it is crucial to develop rationally Ni-based catalysts highly resistant to coking and sintering. In this scenario, the addition of small amounts of potassium to nickel…

Functionalized biochars as supports for Pd/C catalysts for efficient hydrogen production from formic acid

Biomass waste product was used to generate biochars as catalytic supports for selective hydrogen production from formic acid. The supports were obtained after pyrolysis in CO2 atmosphere of non-pretreated and che-mically ZnCl2 activated raw materials (vine shoot and crystalline cellulose). The support series includes materials with different textural properties and surface chemistry. The support nature…

(NH4)4[NiMo6O24H6].5H2O / g-C3N4 materials for selective photo-oxidation of Csingle bondO and Cdouble bondC bonds

Novel composite photo-catalysts having (NH4)(4)[NiMo6O24H6]center dot 5H(2)O Polyoxometalate (POM) species deposited over g-C3N4 are synthesized. Materials were characterized through a multitechnique approach showing the stability of the carbon nitride component both through the synthesis process and under reaction. Contrarily, the POM component evolves under reaction conditions to maximize the interaction with the support. Such a…