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Electrochemical deposition has emerged as a novel approach to fabricate metal–organic framework (MOF) films. Here, for the first time, an aqueously cathodic deposition (ACD) approach is developed to fabricate ZIF‐8 type of MOF membranes without addition of any supporting electrolyte or modulator. The fabrication process uses 100% water as the sole solvent and a low‐defect density membrane is obtained in only 60 min under room temperature without any pre‐synthesis treatment. The membrane exhibits superior performance in C3H6/C3H8 separation with 182 GPU C3H6 permeance and 142 selectivity, making it sit at the upper bound of permeance versus selectivity graph, outperforming majority of the published data up to 2019. Notably, this approach uses an extremely low current density (0.13 mA cm−2) operated under an ultrafacile apparatus set‐up, enabling an attractive way for environmentally friendly, energy efficient, and easily scalable MOF membrane fabrications. This work demonstrates a great potential of aqueously electrochemical deposition of MOF membrane in the future research. [ABSTRACT FROM AUTHOR]

A low-cost natural silicate ore supported Fe 2 O 3 (FeSO) was synthesized for catalytic ozonation of sulfamethoxazole (SMX). XRD, SEM-EDS, BET, FTIR and XPS results of the FeSO catalyst confirmed that the natural silicate ore was successfully modified with iron oxide. The effects of key factors, such as catalyst dosage, initial solution pH, reaction temperature, inorganic anions and initial concentration, on ozonation degradation were systemically investigated. The degradation rate of SMX (20 mg L -1 ) was 88.1% after 30 min, compared with only 35.1% SMX degradation rate in the absence of the catalyst, and the total organic carbon (TOC) removal reached 49.1% after 60 min. Reaction mechanisms revealed that surface hydroxyl groups of FeSO were a critical factor for hydroxyl radical (˙OH) production leading to fast SMX degradation in the ozone decomposition process. The degradation products were detected, and the possible pathways of SMX were then proposed. This study provides guidance for preparing a low-cost catalyst and analyzing the degradation products and pathways of SMX in the ozonation process, which is of significance in practical industrial applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Oil-in-water (O/W) emulsion is one type of oily wastewater produced by many industries. The treatment of and resource recovery from O/W emulsions are very challenging. Unlike bulk or floating oil, which can be successfully abstracted from wastewater by hydrophobic/oleophilic materials, the abstraction of emulsified oil is not easy because of its highly hydrophilic surface composed of dense surfactants. Separate reclamation of miscible oil and surfactant through a green approach is even more difficult. Here, we report that a CO 2 -responsive material can abstract emulsified oil and demulsify the oil droplets. Moreover, it can release the abstracted oil and surfactant separately. This material exhibited a very high adsorption capacity for emulsified oil (14 g g -1 ). Upon switching the surface wettability of the material under CO 2 or synthetic flue gas sparging, coalesced oil was reclaimed while the surfactant was retained inside the pores. The hydrophobic character of the material was retrieved when CO 2 was purged with nitrogen sparging or air heating. Then, the surfactant was reclaimed by elution with diluted alkali/ethanol. Oil and surfactant were thus separately reclaimed from the O/W emulsion. High rates of oil removal, oil recovery, and surfactant recovery were maintained during repeated adsorption/desorption operations. This work provides a potentially sustainable and green way for O/W emulsion treatment and resource recovery.