[Research Advances in Removal Efficiency and Mechanism of Microplastics in Drinking Water Treatment Plants].

Microplastics, as a novel type of environmental pollutant, have attracted notable attention in environmental research due to their widespread distribution and potential biological toxicity. Drinking water treatment plants play a crucial role in ensuring the safety of the water supply, with a particular focus on the removal efficiency of microplastics in drinking water treatment plants. Different treatment processes in water plants exhibit various removal efficiencies of microplastics and they operate through distinct removal mechanisms.

Biodegradation-assisted removal of sulfur-based odor compounds in rural drinking water using durable chitosan/polyvinyl alcohol biochar aerogels.

Rural drinking water often suffers from unpleasant odors like dimethyl sulfide (DMDS) and dimethyl trisulfide (DMTS) due to poor raw water quality and limited treatment options. This study introduces durable chitosan/polyvinyl alcohol (PVA) biochar aerogels-supported bioflims in ultrafiltration (BAB-UF) reactors, where the incorporation of PVA significantly enhances structural integrity, biodegradation resistance, and functional lifespan, providing an efficient, sustainable solution for removing odorous compounds from rural water. Experimental results showed the enhanced chitosan/PVA porous biochar aerogels (CPPCA) displayed excellent biocapacity and structural stability.

Effective and mechanistic insights into shale gas wastewater reverse osmosis concentrate treatment using ozonation-biological activated carbon process.

Reverse osmosis (RO) plays a pivotal role in shale gas wastewater resource utilization. However, managing the reverse osmosis concentrate (ROC) characterized by high salinity and increased concentrations of organic matter is challenging. In this study, we aimed to elucidate the enhancement effects and mechanisms of pre-ozonation on organic matter removal efficacy in ROC using a biological activated carbon (BAC) system.

Cobalt based bimetallic catalysts for heterogeneous electro-Fenton adapting to vary pH for HEDP and MIT degradation.

Most of the materials studied as catalysts in the electro-Fenton system are variants of iron oxide or iron hydroxide. However, iron-based catalysts often exhibit weak catalytic capabilities under neutral and alkaline conditions. In this work, we synthesized three cobalt based bimetallic oxides, CoCuOx, CoAlOx, and CoNiOx, using hydrothermal method and evaluated them as catalysts for the heterogeneous electro-Fenton system to remove 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) and Methylisothiazolinone [2-methyl-4-isothiazolin-3-one] (MIT).

Removal of 6-methylquinoline from shale gas wastewater using electrochemical carbon nanotubes filter.

6-Methylquinoline (6-MQ) is identified as a high-concentration organic compound pervasive in shale gas wastewater (SGW) and poses a significant risk of environmental pollution. In response, this study aimed to address these challenges by introducing an innovative electrochemical membrane constructed with multi-walled carbon nanotubes (CNTs) for the removal of 6-MQ. The investigation systematically explored the impact of voltage, initial pollutant concentration, and salinity on the performance of the electrochemical CNTs filter.

Characterizing hazardous substances of shale gas wastewater from the upper Yangtze River: A focus on heavy metals and organic compounds.

In the last decade, rapid shale gas exploration in upper Yangtze River ecological zone in China has led to increasing concerns about the environmental impact of shale gas wastewater (SGW). However, our understanding of the types of potential hazardous substances of SGW remains limited. In this study, eight SGW samples from three shale gas regions in upper Yangtze River: the Sichuan Basin, the Guizhou Plateau, and the Three Gorges Area were collected, and their general water quality, trace metals, and organic compounds were comprehensively analyzed.

Potential hazards of typical small molecular organic matters in shale gas wastewater for wheat irrigation: 2-butoxyethanol and dimethylbenzylamine.

2-butoxyethanol (BE) and dimethylbenzylamine (DMBA) are small molecular organic compounds commonly found in shale gas wastewater (SGW) and environmental samples, yet their environmental risks in exposure and irrigation reuse have not been thoroughly studied. From the perspectives of physicochemical properties and toxicity, seven groups of irrigation treatment were designed for wheat irrigation according to the concentration gradient. Overall, wheat growth was normal, but higher DMBA concentrations resulted in more severe growth inhibition.

Multi-omics analysis to reveal key pathways involved in low C/N ratio stress response in Pseudomonas sp. LW60 with superior nitrogen removal efficiency.

In practical engineering, nitrogen removal at low temperatures or low C/N ratios is difficult. Although strains can remove nitrogen well at low temperatures, there is no research on the performance and deep mechanism of strains under low C/N ratio stress. In this study, Pseudomonas sp.

Tracing microplastics in rural drinking water in Chongqing, China: Their presence and pathways from source to tap.

Despite the significant attention given to microplastics in urban areas, our understanding of microplastics in rural drinking water systems is still limited. To address this knowledge gap, we investigated the presence and pathways of microplastics in rural drinking water system, including reservoir, water treatment plant (WTP), and tap water of end-users. The results showed that the treatment processes in the WTP, including coagulation-sedimentation, sand-granular active carbon filtration, and ultrafiltration, completely removed microplastics from the influent.

Efficient nitrogen removal by a novel extreme strain, Pseudomonas reactans WL20-3 under dual stresses of low temperature and high alkalinity: Characterization, mechanism, and application.

Although many studies report the resistance of heterotrophic nitrification-aerobic denitrification (HN-AD) strains to single environmental stress, there is no research on its resistance to dual stresses of low temperature and high alkalinity. A novel bacterium Pseudomonas reactants WL20-3 isolated in this study showed removal efficiencies of 100%, 100%, and 97.76% for ammonium, nitrate, and nitrite, respectively, at 4 °C and pH 11.

A novel hypothermic strain, Pseudomonas reactans WL20-3 with high nitrate removal from actual sewage, and its synergistic resistance mechanism for efficient nitrate removal at 4 °C.

Nitrate can be well removed by bacteria at 25-30 °C. However, nitrate removal almost ceases at temperatures lower than 5 °C. In this study, a novel hypothermic strain, Pseudomonas reactans WL20-3 exhibited an excellent aerobic nitrate removal ability at 4 °C.

Janus Membrane with Hydrogel-like Coating for Robust Fouling and Wetting Resistance in Membrane Distillation.

Membrane distillation (MD) is a promising technique for water reclamation from hypersaline wastewater. However, fouling and wetting of the hydrophobic membranes are two prominent challenges for the widespread application of MD. Herein, we developed an antiwetting and antifouling Janus membrane comprising a hydrogel-like polyvinyl alcohol/tannic acid (PVA/TA) top layer and a hydrophobic polytetrafluoroethylene (PTFE) membrane substrate via a facile and benign strategy combining mussel-amine co-deposition with the shrinkage-rehydration process.

Dissolved organic matter in complex shale gas wastewater analyzed with ESI FT-ICR MS: Typical characteristics and potential of biological treatment.

Knowledge on the composition and characteristics of dissolved organic matter (DOM) in complex shale gas wastewater (SGW) is critical to evaluate environmental risks and to determine effective management strategies. Herein, five SGW samples from four key shale gas blocks in the Sichuan Basin, China, were comprehensively characterized. Specifically, FT-ICR MS was employed to provide insights into the sources, composition, and characteristics of SGW DOM.

Water footprint of shale gas development in China in the carbon neutral era.

The production of shale gas in China has repercussions for the global energy landscape and carbon neutrality. However, limited and threatened water resources may hinder the expansion of shale-derived natural gas, one of China's most promising development prospects. Coupling historical trends with policy guidance, we project that baseline water stress will intensify in two-thirds of China's provinces in the next decade.

Safe purification of rural drinking water by biological aerated filter coupled with ultrafiltration.

Water resources of many rural areas are usually lakes or reservoirs, which can be easily affected by run-off, non-point source pollution and are often of poorer quality compared with urban water sources. Drinking water supply in remote rural areas usually suffers from various challenges, such as the high cost of construction and maintenance of centralized drinking water treatment plants and pipe networks, due to the dispersed nature of villages, which are often located in varied and complex topographies. In this study, a combined process comprising biological aerated filter (BAF) combined with ultrafiltration was developed to treat polluted reservoir water.

Occurrence of Iodophenols in Aquatic Environments and the Deiodination of Organic Iodine with Ferrate(VI).

Toxic and odorous iodophenols are commonly identified as disinfection by-products (DBPs) in drinking water. Herein, ng/L levels of iodophenols were identified in river water, wastewater treatment plant effluent, and medical wastewater, with the simultaneous identification of μg/L to mg/L levels of iodide (I) and total organic iodine (TOI). Oxidation experiment suggested that the I, TOI, and iodophenols could be oxidized by ferrate [Fe(VI)], and more than 97% of TOI had been transformed into stable and nontoxic IO.

Shale gas wastewater characterization: Comprehensive detection, evaluation of valuable metals, and environmental risks of heavy metals and radionuclides.

Shale gas wastewater (SGW) has great potential for the recovery of valuable elements, but it also poses risks in terms of environmental pollution, with heavy metals and naturally occurring radioactive materials (NORM) being of major concerns. However, many of these species have not been fully determined. For the first time, we identify the elements present in SGW from the Sichuan Basin and consequently draw a comprehensive periodic table, including 71 elements in 15 IUPAC groups.

Granular activated carbon (GAC) fixed bed adsorption combined with ultrafiltration for shale gas wastewater internal reuse.

Membrane processes are widely applied in shale gas flowback and produced water (SGFPW) reuse. However, particulate matters and organic matters aggravate membrane fouling, which is one of the major restrictions on SGFPW reuse. The present study proposed fixed bed adsorption using granular activated carbon (GAC) combined with ultrafiltration (UF) for the first time to investigate the treatment performance and membrane fouling mechanism.

Millions of microplastics released from a biodegradable polymer during biodegradation/enzymatic hydrolysis.

In this article, we show that enzymatic hydrolysis of a biodegradable polyester (poly(ε-caprolactone)) by Amano Lipase PS in an aqueous (buffer) environment yielded rapidly an excessive number of microplastic particles; merely 0.1 g of poly(ε-caprolactone) film was demonstrated to yield millions of particles. There were also indications of non-enzymatic hydrolysis at the same conditions, but this did not yield any particles within the time frame of the experiment (up to 6 days).

Efficient removal of organic compounds from shale gas wastewater by coupled ozonation and moving-bed-biofilm submerged membrane bioreactor.

Shale gas wastewater (SGW) with complex composition and high salinity needs an economical and efficient method of treatment with the main goal to remove organics. In this study, a coupled system consisting of ozonation and moving-bed-biofilm submerged membrane bioreactor (MBBF-SMBR) was comprehensively evaluated for SGW treatment and compared with a similar train comprising ozonation and submerged membrane bioreactor (SMBR) without addition of carriers attaching biofilm. The average removal rates of MBBF-SMBR were 77.

Can pre-ozonation be combined with gravity-driven membrane filtration to treat shale gas wastewater?

Low-cost gravity-driven membrane (GDM) filtration has the potential to efficiently manage highly decentralized shale gas wastewater (SGW). In this work, the feasibility of combining low dosage pre-ozonation with the GDM process was evaluated in the treatment of SGW. The results showed that pre-ozonation significantly increased the stable flux (372%) of GDM filtration, while slightly deteriorating the quality of the effluent water in terms of organic content (-14%).

Organics removal from shale gas wastewater by pre-oxidation combined with biologically active filtration.

Biological treatment technology is increasingly explored in shale gas wastewater (SGW) treatment owing to its cost effectiveness and requires efforts to improve its efficacy. In this work, ozone and ferrate(VI) oxidation pre-treatment were evaluated to enhance the performance of the subsequent biologically active filtration (BAF) in the removal of organic contaminants. The oxidation improved the SGW biodegradability and organic composition under relative high salinity (~20 g/L).

Green and sustainable method of manufacturing anti-fouling zwitterionic polymers-modified poly(vinyl chloride) ultrafiltration membranes.

The nonsolvent induced phase separation (NIPS) method for ultrafiltration (UF) membrane fabrication relies on the extensive use of traditional solvents, thus ranking first in terms of ecological impacts among all the membrane fabrication steps. Methyl-5-(dimethylamino)-2-methyl-5-oxopentanoate (PolarClean), as a green solvent, was utilized in this study to fabricate poly(vinyl chloride) (PVC) UF membranes. Subsequently, in post-treatment process, zwitterionic polymer, [2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide (DMAPS), was grafted onto the membrane surface to enhance its anti-fouling properties using a greener surface-initiated activator regenerated by electron transfer-atom transfer radical polymerization (ARGET-ATRP) reaction.

A Critical Review of Membrane Wettability in Membrane Distillation from the Perspective of Interfacial Interactions.

Hydrophobic membranes used in membrane distillation (MD) systems are often subject to wetting during long-term operation. Thus, it is of great importance to fully understand factors that influence the wettability of hydrophobic membranes and their impact on the overall separation efficiency that can be achieved in MD systems. This Critical Review summarizes both fundamental and applied aspects of membrane wetting with particular emphasis on interfacial interaction between the membrane and solutes in the feed solution.