Removal of toluene over bi-metallic Pt–Pd-SBA-15 catalysts: Kinetic and mechanistic study

Selective Hydrogenation of the Carbonyls in Furfural and 5-Hydroxymethylfurfural Catalyzed by PtNi Alloy Supported on SBA-15 in Aqueous Solution Under Mild Conditions

“…Compared with pure silica SBA-15, the BET surface areas and pore volumes of all the synthesized catalysts had a decrease after metal introduction. The average pore diameter of PtNi/SBA-15 decreased obviously, due to the potential encapsulation of nanoalloys into the mesochannels( Chang et al, 2020 ). However, the average pore diameters of Pt/SBA-15, Ni/SBA-15, and Pt-Ni/SBA-15 slightly increased, which could be attributed to the blockage of the small micropores by nanoparticles ( Zhou et al, 2020 ).…”

“…However, the majority of metal particles of Pt-Ni/SBA-15 intensively grew on the edge of SBA-15, rather than being evenly distributed on the tunnel of SBA-15. These results indicated that the metal ions might migrate to the surface and agglomerate during the ordinary incipient impregnation process, which limited the metal dispersion and decreased the metal atom utilization to some extent ( Chang et al, 2020 ). For PtNi/SBA-15 catalyst, small metal particles with 5.8 nm of average diameter were uniformly distributed on SBA-15, which could be attributed to the fact that PVP played an important role in the novel synthesis method of PtNi/SBA-15.…”

“…In the hydrothermal synthesis process, PVP, as surfactant with the isolation function, contributed to form PtNi nanoalloys and control the PtNi alloys size, and structure ( Xu et al, 2014 ). In the impregnation and calcination process, the use of PVP prevented the aggregation of metal particles and successfully fixed the metal particles in the SBA-15 pores channel, which inhibited their migration onto the surface ( Chang et al, 2020 ). Furthermore, the smaller particle size of PtNi/SBA-15 would further increase the metal atom utilization and the active catalytic surface, which could minimize the metal usage and made the PtNi/SBA-15 catalyst more ecologically friendly while maintaining the efficient catalytic performance.…”

“…In Eq. 4 , the metal dispersion for bimetallic catalyst was calculated based on TEM analysis according to the literatures, where the value 6.59 was obtained from calculation by assuming spherical metal crystallites of uniform diameter ( Jin et al, 2008 ; Chang et al, 2020 ; Zhou et al, 2020 ). The site density was calculated from the average diameter of platinum and nickel crystallites estimated by TEM ( Wu et al, 2012 ).…”

Insights into the role of strontium in catalytic combustion of toluene over La1−xSrxCoO3 perovskite catalysts

“…Under the conditions of a GHSV of 800 000 mL g À1 h À1 and 7 mg sample, the kinetic study was carried out, and the activation energy (E a ) of toluene oxidation was calculated according to the Arrhenius equation. The inlet gaseous toluene concentration was 600 ppm in order to ensure that the conversion of toluene was below 20%, 19 to maximize the elimination of the influence of internal and external diffusion.…”