Fe/ZSM-11 as a novel and efficient photocatalyst to degrade Dichlorvos on water solutions

Abstract

Iron modified ZSM-11 zeolites were tested as heterogeneous catalysts in the photodegradation of Dichlorvos water solutions. ZSM-11 zeolite matrixes were synthesized by the hydrothermal method and iron was incorporated by the wet impregnation method in four different concentrations. Catalysts samples were characterized by several techniques (XRD, BET, UV-vis DRS, ICP-OES, TPR, EPR) in order to confirm structure, crystallinity and iron species present. a-Fe 2 O 3 was detected by XRD in higher iron content samples and it presence was confirmed by EPR, TPR and UV-vis DRS. Band gap energies for Fe/ZSM-11 samples were closer to that reported for pure a-Fe 2 O 3 . The materials so far characterized were tested as heterogeneous catalyst in Dichlorvos photodegradation. Fe/ZSM-11 with a 6 wt% of iron incorporation showed the best catalytic behavior. Higher iron loadings showed lower degradation efficiencies. This material is reusable for at least six catalytic cycles without considerable differences among the DDVP amount degraded.

Insight into the efficient oxidation of methyl-ethyl-ketone over hierarchically micro-mesostructured Pt/K-(Al)SiO2 nanorod catalysts: Structure-activity relationships and mechanism

“…From Fig. 3C, for KA-NRS and KA-SFNS support, the band at around 241.8 nm was assigned to Al-O charge-transfer transition of four-coordinated framework, which refers to structures with highly ordered octahedral symmetry and stabilized in the framework of silica [33]. This band shifts toward high energy of 257.2 nm after loading Pt nanoparticles due to Al-O-Pt [34].…”

Integrating pore interconnectivity and adaptability in a single crystal hierarchical zeolite for liquid alkylation

“…Figure 1 showed the powder X‐ray diffraction patterns for various MEL zeolite samples; it was observed that all the synthesized samples exhibited the characteristic peaks (such as 2θ = 7.9, 8.8, 14.8, 23.1, and 23.9°) of an MEL topologic framework, 23,24 indicating that the MEL zeolites were successfully fabricated in the present work. No other detectable diffraction peaks for metal phases, such as large iron oxides, were found, which indicated a substantial absence of large metal crystallites.…”

Decoloración fotocatalítica del Rojo de Alizarina S empleando nanocatalizadores de hierro

“…Como puede observarse, el aumento del contenido hierro genera una disminución del área superficial de los nanotubos. Este efecto es atribuido al bloqueo que produce la agregación de la fase activa sobre la superficie interna del nanotubo (Gomez et al, 2017). El contenido de Fe en los nanomateriales, determinada por AA, fue muy similar a la cantidad teórica.…”