Correction: Enantioselective synthesis of sulfoxide using an SBA-15 supported vanadia catalyst: a computational elucidation using a QM/MM approach

Correction for ‘Enantioselective synthesis of sulfoxide using an SBA-15 supported vanadia catalyst: a computational elucidation using a QM/MM approach’ by Navjot Kaur et al., Phys. Chem. Chem. Phys., 2017, 19, 25059–25070.

Enantioselective synthesis of sulfoxide using an SBA-15 supported vanadia catalyst: a computational elucidation using a QM/MM approach

Metal catalyzed asymmetric oxidation of prochiral sulfides is one of the prevailing strategies to produce enantiopure sulfoxides.

Characterization of vanadia catalysts on structured micro-fibrous glass supports for selective oxidation of hydrogen sulfide

This work is focused on the characterization of a novel vanadium pentoxide catalysts on a glass-fiber support. The catalyst support consists of a non-porous glass-fiber fabric covered with an additional external surface layer of porous secondary support of SiO2. The vanadia active component is synthesized from vanadyl oxalate precursor by means of an impulse surface thermo-synthesis method. Such catalysts demonstrate high activity and appropriate selectivity in the reaction of H2S oxidation by oxygen into sulfur in the practically important temperature range below 200°C. According to the characterization data, the freshly prepared vanadia catalyst partially consists of mostly the amorphous and badly ordered vanadia with some part of the wellcrystallized V2O5 phase. Under the reaction conditions the main part of vanadia in the catalyst remains in the amorphous V2O5 form, while the less part becomes reduces into of VO2 and other vanadium oxides (such as VO, V2O3 V3O7 and V4O9). Most probably, the crystallized V2O5 in course of reaction is responsible for the deep oxidation of hydrogen sulphide into SO2, while the lower vanadium oxides promote the selective H2S oxidation into elemental sulfur.

Characterization and Deactivation Study of Mixed Vanadium and Potassium Oxide Supported on Microemulsion-Mediated Titania Nanoparticles as Catalyst in Oxidative Dehydrogenation of Propane

The influence of potassium addition to the vanadia supported on the microemulsion-mediated TiO2 nanoparticles in propane oxidative dehydrogenation was studied. Raman spectroscopy demonstrated that the addition of potassium caused enhanced dispersion of vanadia species on the support surface. Also, potassium existence affects the H2 temperature programmed reduction maximum reduction temperature and shifted it to 520°C, which was in accordance with its lesser catalytic activity. Nevertheless, a propylene selectivity enhancement was observed by potassium addition. In spite of the fact that the catalytic performance loss was not severe in vanadia-supported TiO2 anatase, potassium addition led to improve the catalyst lifetime. After deactivation test, potassium-containing vanadia catalyst possessed lower surface area loss (i.e. from 52 to 49 m2 g−1). Average crystallite size of potassium-containing vanadia catalyst exhibited lower decrease than that of potassium-free vanadia catalyst after deactivation test. According to Raman spectra, deactivation phenomena had influenced the population of vanadia species so that monovanadates decreased and polyvanadates increased.

Higher propene yield by tailoring operating conditions of propane oxidative dehydrogenation over V2O5/γ-Al2O3

Supported vanadia catalyst was successfully synthesized using wet impregnation of ?-Alumina to study Propane Oxidative Dehydrogenation (POD). The prepared catalysts were characterized with XRD, BET, and TPR tests. In a broad temperature range (340 to 630?C), effects of vanadia loading (2.7, 5.4, and 9 wt%) and propane to oxygen ratio (3/1 to 1/3) were thoroughly investigated on propane conversion as well as propene yield at atmospheric pressure. Results indicate that by increasing the vanadia content the activity of catalyst increases while selectivity to propene decreases monotonically. As the temperature increases from 340?C to 630?C, yield to propene shows ascending behavior in case of all catalyst samples. Yield to propene shows a climax with changing propane to oxygen ratio from 3/1 to 1/3. The yield increases with increase in oxygen partial pressure of feed until equimolar ratio of propane and oxygen, then it declines with further increase of oxygen partial pressure. A maximum propene yield of 17% was experienced on catalyst with 2.7wt% vanadia at temperatures at 550?C.