Enhancing electricity generation and pollutant degradation in microbial fuel cells using cyanobacteria-derived biochar electrodes.

Utilizing microbial fuel cells (MFCs) technology to simultaneously achieve efficient biopower generation and pollutant degradation is a persistent pursuit. However, the limited rate of extracellular electron transfer (EET) and the availability of electrode materials remain key factors limiting the practical application of MFCs. In this article, modified carbon derived from cyanobacteria is applied to modify electrodes and assemble MFCs.

Inhibit or promote? Trade-off effect of dissolved organic matter on the laccase-mediator system.

A biocatalytic system comprising fungal laccase and mediators can generate phenol radicals and efficiently eliminate various triarylmethane dyes. This study systematically explores the kinetic impact of dissolved organic matter (DOM), represented by humic substance (HS consisting of 90% fulvic acid, from lignite), on the decolorization of seven typical triarylmethane dyes by Trametes versicolor laccase and twenty natural mediators. Among these, 4-hydroxybenzyl alcohol (4-HA) and methyl violet (MV) undergo in-depth investigation regarding degradation products, pathways, and reaction mechanisms.

Carbon slow-release and enhanced nitrogen removal performance of plant residue-based composite filler and ecological mechanisms in constructed wetland application.

Stable carbon release and coupled microbial efficacy of external carbon source solid fillers are the keys to enhanced nitrogen removal in constructed wetlands. The constructed wetland plant residue Acorus calamus was cross-linked with poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) to create composite solid carbon source fillers (Ac-BDPs). The study demonstrated the slow release of carbon sources from Ac-BDPs with 35.

Efficient photochemical conversion of naproxen by butanedione: Role of energy transfer.

Photochemical active species generated from photosensitizers, e.g., dissolved organic matter (DOM), play vital roles in the transformation of micropollutants in water.

Visible light-driven oxidation of non-native substrate by laccase attached on Ru-based metal-organic frameworks.

Light-induced electron transfer can broaden the substrate range of metalloenzyme. However, the efficiency of photo-enzyme coupling is limited by the poor combination of photosensitizer or photocatalyst with enzyme. Herein, we prepared the nano-photocatalyst MIL-125-NH@Ru(bpy) by in site embedding ruthenium pyridine-diimine complex [Ru(bpy) into metal organic frameworks MIL-125-NH and associated it with multicopper oxidase (MCO) laccase.

Modeling, optimization and understanding of adsorption process for pollutant removal via machine learning: Recent progress and future perspectives.

It is crucial to reduce the concentration of pollutants in water environment to below safe levels. Some cost-effective pollutant removal technologies have been developed, among which adsorption technology is considered as a promising solution. However, the batch experiments and adsorption isotherms widely employed at present are inefficient and time-consuming to some extent, which limits the development of adsorption technology.

Antimony (Sb) pollution control by coagulation and membrane filtration in water/wastewater treatment: A comprehensive review.

Antimony (Sb) pollution in the water environment caused by the large-scale mining of Sb ore and the wide use of Sb-containing products seriously endangers human health and poses a great threat to the ecological environment. Coagulation is one of the most cost-effective technologies for Sb pollution control in water/wastewater treatment and has been widely used. However, a comprehensive understanding of Sb pollution control by coagulation, from fundamental research to practical applications, is lacking.

Heterogeneous catalysis mediated by light, electricity and enzyme via machine learning: Paradigms, applications and prospects.

Energy crisis and environmental pollution have become the bottleneck of human sustainable development. Therefore, there is an urgent need to develop new catalysts for energy production and environmental remediation. Due to the high cost caused by blind screening and limited valuable computing resources, the traditional experimental methods and theoretical calculations are difficult to meet with the requirements.

An all-in-one approach for synthesis and functionalization of nano colloidal gold with acetylacetone.

Controllable synthesis, proper dispersion, and feasible functionalization are crucial requirements for the application of nanomaterials in many scenarios. Here, we report an all-in-one approach for the synthesis and functionalization of gold nanoparticles (AuNPs) with the simplest-diketone, acetylacetone (AcAc). With this approach, the particle size of the resultant AuNPs was tunable by simply adjusting the light intensity or AcAc dosage.

[Fabrication of Supported Titanium Xerogel Adsorbent and Performance Evaluation for Arsenite Removal].

Although the adsorption capacity of titanium xerogel(TAX) for arsenite(As(Ⅲ)) is high(254 mg·g), the adsorption rate is slow. Therefore, TAX was loaded onto activated carbon, sponge, and resin to fabricate a supported adsorbent, and the arsenite removal performance was evaluated. Except sponge, activated carbon and resin could successfully load TAX.

Photochemical Synthesis of Selenium Nanospheres of Tunable Size and Colloidal Stability with Simple Diketones.

Temporal and spatial segregations are two fundamental requirements for the successful synthesis of nanoparticles (NPs). To obtain colloidally stable selenium nanospheres (SeNSs), surfactants or polymers are generally needed as structure-directing agents or stabilizers in the reduction approaches for SeNP synthesis. The addition of such chemicals sacrifices the purity of the obtained SeNPs and, therefore, is detrimental to the applications.

Role of complexation in the photochemical reduction of chromate by acetylacetone.

Organic ligands can alter the redox behavior of metal species through the generation of metal-ligand complexes. Photo-induced complexation between ligands and metals is an important, but under-appreciated, aspect of process. Acetylacetone (AA) is a good chelating agent due to keto-enol tautomerization.

Metal-free generation of hydroxyl radicals by benzoate-mediated decomposition of peroxides.

A type of metal-free organic photo-Fenton-like reaction was developed, which was realized by a combination of UV with benzoates and peroxides. The findings here not only provide a novel ˙OH production pathway, but also shed new light on the accurate quantification, better use or prevention of ˙OH in many scenarios.

Reduction of chromate with UV/diacetyl for the final effluent to be below the discharge limit.

Reduction of Cr(VI) to Cr(III) is helpful to lower the toxicity risk and also necessary for the removal of chromium from waste streams through alkaline precipitation. We compared the reduction of Cr(VI) in six UV systems with oxalic acid (OA), ethylenediaminetetraacetic acid (EDTA), salicylic acid (SA), hydroquinone (HQ), acetylacetone (AA) and diacetyl (BD) as chelating or non-chelating photo-activators. Overall, HQ, AA and BD were much more efficient than the carboxylic acids for the photo-reduction of Cr(VI).

Ligand effects on arsenite removal by zero-valent iron/O: Dissolution, corrosion, oxidation and coprecipitation.

Ligands may increase the yields of reactive oxygen species (ROS) in zero-valent iron (ZVI)/O systems. To clarify the relationship between the properties of ligands and their effects on the oxidative removal of contaminants, five common ligands (formate, acetate, oxalate, ethylenediaminetetraacetic acid (EDTA), and phosphate) as well as acetylacetone (AA) were investigated with arsenite (As(III)) as the target contaminant at three initial pH values (3.0, 5.

Sludge reduction and cost saving in removal of Cu(II)-EDTA from electroplating wastewater by introducing a low dose of acetylacetone into the Fe(III)/UV/NaOH process.

Cu(II)-EDTA is highly stable in a wide pH range (3.0∼12.0) and hard to be removed by the conventional precipitation method.

Enhanced Photooxidation of Hydroquinone by Acetylacetone, a Novel Photosensitizer and Electron Shuttle.

Quinones are important electron shuttles as well as micropollutants in the nature. Acetylacetone (AA) is a newly recognized electron shuttle in aqueous media exposed to UV irradiation. Herein, we studied the interactions between AA and hydroquinone (QH) under steady-state and transient photochemical conditions to clarify the possible reactions and consequences if QH and AA coexist in a solution.

Effects of acetylacetone on the thermal and photochemical conversion of benzoquinone in aqueous solution.

Quinones are components of electron transport chains in photosynthesis and respiration. Acetylacetone (AA), structurally similar to benzoquinone (BQ) for the presence of two identical carbonyl groups, has been reported as a quinone-like electron shuttle. Both BQ and AA are important chemicals in the aquatic environment.

Coagulation removal of fluoride by zirconium tetrachloride: Performance evaluation and mechanism analysis.

Fluoride (F) pollution is a worldwide issue. Coagulation with aluminum (Al) salts is an efficient and economical method for the removal of F. However, due to the strong complexation between Al and F, the residual F and Al after coagulation usually exceed the limits.

Adsorption and Reduction of Cr(VI) Together with Cr(III) Sequestration by Polyaniline Confined in Pores of Polystyrene Beads.

The simultaneous reduction and sequestration of Cr(VI) from wastewater is desirable as a cost-effective and environmentally friendly approach. In this study, we execute a one-step facile synthesis strategy on polyaniline (PANI) composites based on aniline adsorption and polymerization on pores of millimeter-scale polystyrene balls (PANI@PS). The well-defined PANI@PS increased the removal capacity of Cr(VI) by 5.

Nonnegligible Generation of Hydroxyl Radicals from UVC Photolysis of Aqueous Nitrous Oxide.

Nitrous oxide (NO) is widely used in radiation-chemistry and photochemistry as a scavenger to convert a hydrated electron ( e) into a hydroxyl radical (·OH). However, few investigations pay attention to the photochemistry of dissolved NO itself. The effects of purged NO on photochemical processes are unclear and neglected.

Feasibility of the UV/AA process as a pretreatment approach for bioremediation of dye-laden wastewater.

Biodegradability and toxicity are two important indexes in considering the feasibility of a chemical process for environmental remediation. The acetylacetone (AA) mediated photochemical process has been proven as an efficient approach for dye decolorization. Both AA and its photochemical degradation products had a high bioavailability.

Acetylacetone as an efficient electron shuttle for concerted redox conversion of arsenite and nitrate in the opposite direction.

The redox conversion of arsenite and nitrate has direct effects on their potential environment risks. Due to the similar reduction potentials, there are few technologies that can simultaneously oxidize arsenite and reduce nitrate in one process. Here, we demonstrate that a diketone-mediated photochemical process could efficiently do this.

Applicability of light sources and the inner filter effect in UV/acetylacetone and UV/HO processes.

Light source is a crucial factor in the application of a photochemical process, which determines the energy efficiency. The performances of acetylacetone (AA) in conversion of aqueous contaminants under irradiation with a low-pressure mercury lamp, a medium-pressure mercury lamp, a xenon lamp, and natural sunlight were investigated and compared with those of HO as reference. In all cases, AA was superior to HO in the degradation of Acid Orange 7.