Search

Efficient sulfate radical-based advanced oxidation processes (SR-AOPs) are important for treating organic contaminants of industrial wastewater. To achieve this goal, tannic acid (TA)–modified skin collagen fibers (CFs) were prepared for the enhanced immobilization of Fe3+ based on multiple complexation interactions, resulting in a heterogeneous catalyst with more catalytic sites (defined as TA-Fe-CFs) for activating peroxymonosulfate (PMS). During the removal of an organic dye (rhodamine B, RhB) from water, the hierarchical TA-Fe-CFs exhibited excellent adsorption capacity at the early stage before the introduction of PMS, which can be ascribed to the π-π interaction between TA and aromatic RhB. Such improved mass transfer of target contaminants into the catalytic support was proved to be beneficial for improving the utilization efficiency of sulfate radicals in subsequent SR-AOPs. After introducing PMS, the reductive TA moieties of the heterogeneous catalyst were able to accelerate the redox cycle of Fe3+/Fe2+ in Fenton reactions, facilitating the activation of PMS to generate sulfate radicals for the degradation of organic RhB. [ABSTRACT FROM AUTHOR]

A novel CO 2 -responsive cotton as an eco-friendly adsorbent derived from poly(4-acryloyloxybenzophenone- co -2-(dimethylamino) ethyl methacrylate) and cotton was fabricated via a facile and fast dip-coating method. As expected, upon CO 2 stimulation, the protonated cotton presented CO 2 -induced "on-off" selective adsorption behaviors toward anionic dyes owing to electrostatic interactions. The adsorption isotherms and kinetics of the CO 2 -responsive cotton toward anionic dyes obeyed the Langmuir isotherm and pseudo-second-order kinetics models, respectively. It is noteworthy that the CO 2 -responsive cotton exhibited high adsorption capacity and ultrafast adsorption rate toward anionic dyes with the maximum adsorption capacities of 1785.71 mg g -1 for methyl orange (MO), 1108.65 mg g -1 for methyl blue (MB), and 1315.79 mg g -1 for naphthol green B (NGB), following the adsorption equilibrium times of 5 min for MO, 3 min for MB, and 4 min for NGB. Moreover, the CO 2 -responsive cotton also exhibited high removal efficiency toward anionic dyes in synthetic dye effluent. Additionally, the CO 2 -responsive cotton could be facilely regenerated via heat treatment under mild conditions and presented stable adsorption properties even after 15 cycles. Finally, the as-prepared CO 2 -responsive cotton exhibited outstanding antibacterial activity against E. coli and S. aureus . In summary, this novel CO 2 -responsive cotton can be viewed as a promising eco-friendly adsorbent material for potential scalable application in dye-contaminated wastewater remediation.