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4-chlorophenol (4-CP) could be rapidly mineralized by using Fenton reaction. However, massive iron sludge will be generated because of the excessive consumption of iron salt and poor recycling of FeIII back to FeII. In this paper, by introducing hydrogen gas and solid catalyst Pd/NH2-MIL-101(Cr) to classic Fenton reactor, the novel system named MHACF-NH2-MIL-101(Cr) was constructed. Much less FeII was needed in this system because the hydrogen could significantly accelerate the regeneration of FeII. The catalyst improved the utilization of H2. The degradation reaction of 4-CP could be driven by using only trace amount of FeII. It could be rapidly degraded by the hydroxyl radical detected by the 4-Hydroxy-benzoicacid which is the oxidative product of benzoic acid and hydroxyl radical. The effects of dosage of ferrous salt, H2O2 and catalyst, H2 flow, Pd content, and initial pH of and concentration of 4-CP aqueous solution were investigated. The robustness and morphology changes of this catalytic material were also systematically analysed. By clarifying the role of this solid MOFs material in this hydrogen-mediated Fenton reaction system, it will provide a new direction for the research and development of advanced oxidation processes with high efficiency and low sludge generation in future. [ABSTRACT FROM AUTHOR]

The article presents a study on fluorescent chemosensors based on thioether amide for palladium. It discusses the use of palladium in various industries, tools for the detection of palladium species, sensing probes for palladium, the fluorescence change in the presence of various metal ions, and the use of fluorescence emission spectra.

Excessive consumption of Fe (II) and massive generation of sludge containing Fe (III) from classic Fenton process remains a major obstacle for its poor recycling of Fe (III) to Fe (II). Therefore, the MHACF‐MIL‐101(Cr) system, by introducing H2, Pd0 and MIL‐101(Cr) into Fenton reaction system, was developed at normal temperature and pressure. In this system, the reduction of FeIII back to FeII by solid catalyst Pd/MIL‐101(Cr) for the storage and activation of H2, was accelerated significantly by above 10‐fold and 5‐fold controlled with the H2‐MIL‐101(Cr) system and H2‐Pd0 system, respectively. However, the concentration of Fe (II) generated by the reduction of Fe (III) could not be detected with the only input of H2 and without the addition of MOFs material. In addition, the apparent consumption of Fe (II) in MHACF‐MIL‐101(Cr) system was half of that in classical Fenton system, while more Fe (II) might be reused infinitely in fact. Accordingly, only trace amount of Fe (II) vs H2O2 concentration was needed and hydroxyl radicals through the detection of para‐hydroxybenzoic acid (p‐HBA) as the oxidative product of benzoic acid (BA) by·OH could be continuously generated for the effective degradation of 4‐chlorophenol(4‐CP). The effects of initial pH, concentration of 4‐CP, dosage of Fe2+, H2O2 and Pd/MIL‐101(Cr) catalyst, Pd content and H2 flow were investigated, combined with systematic controlled experiments. Moreover, the robustness and morphology change of Pd/MIL‐101(Cr) were thoroughly analyzed. This study enables better understanding of the H2‐mediated Fenton reaction enhanced by Pd/MIL‐101(Cr) and thus, will shed new light on how to accelerate Fe (III)/Fe (II) redox cycle and develop more efficient Fenton system. [ABSTRACT FROM AUTHOR]