Dichloromethane catalytic combustion over Co3O4 catalysts supported on MFI type zeolites

Synergistic Effect of ZSM-5 Zeolite in Pt–CeO2–TiO2/ZSM-5 Catalysts for Highly Efficient Catalytic Oxidation of VOCs

“…For the O 1s XPS spectra, three kinds of oxygen species can be observed at BE = 529.8, 531.9, and 532.7 eV assigned to the surface lattice oxygen (O latt ), oxygen within the nonchemical oxide or oxygen-deficient region (O v ) and the surface absorbed water or hydroxyl species (O sur ), respectively. − As shown, only one peak corresponding to O sur species is observed for Pt/ZSM-5 catalyst due to the existence of plentiful silicon hydroxyl groups on the ZSM-5 zeolite surface . Two peaks of O latt and O v appear in the spectra of Pt/CeTi and the O v /O total molar ratio is 0.22.…”

“…49−51 As shown, only one peak corresponding to O sur species is observed for Pt/ ZSM-5 catalyst due to the existence of plentiful silicon hydroxyl groups on the ZSM-5 zeolite surface. 51 More specifically, the peaks α, β, and γ are ascribed to the desorption of NH 3 adsorbed on the weak acid sites and the peak δ is assigned to the desorption of NH 3 that was chemically absorbed on the strong acid sites, 27 while only NH 3 desorption peaks (peaks α, β, and γ) corresponding to the weak acid sites occur for the Pt/CeTi. After peak fitting and quantitative analysis, Figure 10(B) exhibits that the number of strong acid sites and total acid sites of the Pt−CeTi/ZSM-5 catalysts apparently reduce when the CeO 2 −TiO 2 /ZSM-5 mass ratio generally increases, which may be connected to the reducing amount of the ZSM-5 zeolite and the coverage of Bronsted acid sites by the CeO 2 −TiO 2 mixed oxides.…”

Research progress of molecular sieve supported catalysts in catalytic oxidation of chlorine-containing volatile organic compounds

“…Single catalyst has a certain oxidation effect on DCM, but its effect is generally inferior to that of supported catalyst. In the spectrum recorded by Zhang et al [46], compared with the pure Co 3 O 4 catalyst, the A1g band of the Co 3 O 4 /ZSM-5 ratio shifts to a lower frequency, and the analytical peak is about 550℃, which is lower than that of the pure Co 3 O 4 catalyst. During the oxidation process, DCM will be adsorbed by acid sites on the surface of molecular sieve, and chlorine atoms will be removed in the form of HCl.…”

Temperature dependent fabrication of various rod and rhombohedral-shaped mesoporous Co3O4 crystals and their capability towards elimination of toxic Cr(vi) ions from the aquatic environment

“…Some similar types of observations are also reported previously. 69,70 We have also calculated the average crystalline sizes of the sample by using the Debye-Scherrer equation. 71,72 Table 3 summarizes the results which confirmed that at 400 1C, Co 3 O 4 offers the lowest crystalline size.…”