Selective oxidation of H2S to sulfur over vanadia supported on mesoporous zirconium phosphate heterostructure

Abstract

Vanadium oxide supported on mesoporous zirconium phosphate catalysts have been synthesised, characterized and tested in the selective oxidation of H2S to sulphur. The nature of the vanadium species depend on the V-loading of catalyst. Catalysts with a Vcontent lower than 4 wt% present both isolated vanadium species and V2O5 crystallites,

On the origin of the spontaneous formation of nanocavities in hexagonal bronzes (W,V)O3

“…Analysis of reactants and reaction products was carried out online by using gas chromatography and two different chromatographic columns (Molecular Sieve 5A and Porapak T) . 13 …”

Vanadium oxide supported on porous clay heterostructure for the partial oxidation of hydrogen sulphide to sulfur

“…However, supported vanadium oxide catalysts presenting V2O5 crystallites are more stable, as a consequence of the partial reduction of V2O5 to V4O9 which can be proposed as the active and selective crystalline phase when working at reaction temperatures lower than 240 ºC [11]. In both unsupported and supported V2O5-containing catalysts, the formation of V4O9 during the oxidation reaction has been confirmed by operando and in-situ conditions using Raman and XAS spectroscopies, respectively [12].…”

“…Regarding vanadium species, catalysts with low V-loadings show important catalyst decay, especially when working at reaction temperatures below 240 ºC [11]. However, supported vanadium oxide catalysts presenting V2O5 crystallites are more stable, as a consequence of the partial reduction of V2O5 to V4O9 which can be proposed as the active and selective crystalline phase when working at reaction temperatures lower than 240 ºC [11].…”

“…Nonetheless the reduction temperature is still lower than that of bulk V2O5, indicating that the particle size of V2O5 is a key factor in the reducibility of the vanadium species. Thus, the catalysts with small particles of V2O5 present a higher interaction with the support, favoring the reducibility than bulky ones [11,27].…”

“…Vanadium oxide based materials constitute an interesting group of catalysts which have been reported recently as potential catalysts for the partial oxidation of H2S to sulfur [5][6][7][8][9][10][11][12][13]. The supported vanadium oxide has been the most studied catalysts.…”