ZSM-5-KIT-5 (Zk) materials with different amounts of ZSM-5 emulsion were successfully synthesized by a nano self-assembly method.

Zr modified mesoporous alumina Al-TUD-1 with different Zr content was successfully synthesized via sol− gel method and the optimal thermal treatment time was 4 h. The characterization results of HRTEM, XPS and pyridine FT-IR revealed that Zr atoms acted as electronic promoters not only enhanced the sulfidation degree and modulated the morphology of MoS 2 active phases but also brought more acidities into the alumina framework. Additionally, the sulfided catalysts were evaluated using dibenzothiophene (DBT) and FCC diesel as feedstocks, respectively. NiMo/ZrAT-100 catalyst with the largest pore size, the highest active metal sulfidities, as well as the highest total acid and B/L value exhibited the highest HDS (99.1%) and HDN efficiencies (98.7%) in diesel hydrotreating reaction; moreover, it possessed the largest reaction rate constant in DBT HDS reaction. Furthermore, a possible reaction network was also proposed, in which DDS route was the predominant pathway for DBT HDS.

Perfluorooctanoic acid (PFOA) is a widely distributed recalcitrant contaminant. In recent years, advanced oxidation processes have been explored for PFOA degradation, yet factors influencing their efficacy and degradation mechanism are not fully understood. Here, we resolve ambiguity in the literature regarding the role of superoxide in PFOA degradation (e.g., by nucleophilic attack) by considering three pure superoxideproducing systems: KO 2 in dimethyl sulfoxide, xanthine oxidase with hypoxanthine, and WO x /ZrO 2 catalyst with H 2 O 2 . Superoxide production was confirmed in all systems by electron paramagnetic resonance spectroscopy and by precipitation of nitroblue tetrazolium, a common superoxide probe. Positive control experiments showed that the produced superoxide degrades ∼48% of bisphenol A within 1 day, corroborating the fact that superoxide was sufficiently stable and available for reaction in the test systems. However, no PFOA degradation was observed, which was corroborated by the absence of fluoride and degradation byproducts in all three systems. Therefore, other reaction pathways should be explored for PFOA degradation.

Zirconium modified mesoporous materials were successfully synthesized by different methods including direct synthesis and post synthesis (grafting and impregnating).

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