Development and evaluation of a sulfate precipitation method for separating key flocculated-species from titanium-based flocculant.

Key flocculated-species is the pivotal factor influencing the effectiveness of flocculants, which in turn directly determines the performance of mainstream wastewater treatment processes. Recovery of titanium-coagulated sludge and high-efficiency of titanium-coagulation have made titanium-coagulants an attractive hot point. However, the separation of key titanium-based flocculated-species remains a critical bottleneck limiting the advancement of titanium-based flocculant chemistry in water treatment.

Efficient production of singlet oxygen via dioxygen activation on Cu decorated MoS facilitates the elimination of oxytetracycline.

Molecular oxygen (O), a green oxidant, is applied in advanced oxidation processes, which represents one of the current focal points in water treatment research. However, achieving efficient and economical activation of O remains a formidable challenge because of its spin-restricted nature. Herein, zero-valent copper (Cu) modified molybdenum disulfide (MoS) materials were applied as O activators to degrade organic pollutants.

Microenvironment modulation of biocatalyst derived from natural cellulose of wheat straw for enhancing p-nitrophenol degradation via boosting peroxymonosulfate activation.

Defect-rich nitrogen-doped biocatalyst (B-NC) was synthesized from natural cellulose of wheat straw using straightforward mechanical method and one-step pyrolysis approach. In contrast to the nitrogen-doped biocatalyst (NC), by leveraging the synergistic effects of nitrogen dopants and surface defects, the microenvironment-modulated B-NC exhibited the enhanced mass transfer efficiency and a significant improvement in reactivity for p-nitrophenol degradation (111 %-196 %). The catalyst's exceptional performance primarily arose from graphitic N, pyridinic N and CO active sites, which mainly derived from the cellulose structure of wheat straw and nitrogen dopants.

Recent Progress of Layered Double Hydroxide-Based Materials in Wastewater Treatment.

Layered double hydroxides (LDHs) can be used as catalysts and adsorbents due to their high stability, safety, and reusability. The preparation of modified LDHs mainly includes coprecipitation, hydrothermal, ion exchange, calcination recovery, and sol-gel methods. LDH-based materials have high anion exchange capacity, good thermal stability, and a large specific surface area, which can effectively adsorb and remove heavy metal ions, inorganic anions, organic pollutants, and oil pollutants from wastewater.

Boosting interfacial solar steam generation by three-dimensional bilayer cellulose aerogels.

Interfacial solar steam generation (ISSG) provides a sustainable approach of clean water production through desalination and water purification. It is still needed to pursue a fast evaporation rate, high-quality freshwater production, and low-cost evaporators. Herein, a three-dimensional (3D) bilayer aerogel was fabricated using cellulose nanofiber (CNF) as a skeleton filled with polyvinyl alcohol phosphate ester (PVAP), and carbon nanotubes (CNT) as a light absorbing material in the top layer.

(NH)MoS/MnFeO hybrid with multiple active sites boosted activation of peroxymonosulfate for removal of tetracycline.

Advanced oxidation processes (AOPs) based on peroxymonosulfate (PMS) activation have attracted much attention in wastewater treatment. Here, a series of (NH)MoS/MnFeO (MSMF) composites were prepared and used as PMS activators to remove tetracycline (TC) for the first time. When the mass ratio of (NH)MoS to MnFeO was 4.

Capacitive deionization of high concentrations of hexavalent chromium using nickel-ferric-layered double hydroxide/molybdenum disulfide asymmetric electrode.

To decontaminate wastewater affected by high concentrations of aqueous hexavalent chromium (Cr(VI)) and improve the capability of layered double hydroxide (LDH) as an electrode in the capacitive deionization (CDI) process, nickel-ferric-LDH (NiFe-LDH) and NiFe-LDH/molybdenum disulfide (NiFe/MoS) were synthesized using a hydrothermal method. Characterization results indicated that the flower-like cluster framework of MoS was decorated with the NiFe-LDH. Addition of MoS improved the conductivity, capacitance reversibility, charge efficiency, coulombic efficiency, and stability of NiFe/MoS.

Solid slow-release carbon source assembled microbial fuel cell for promoting superior nitrogen removal in an aerobic granular sludge bioreactor.

Although the coupling process of microbial fuel cell (MFC) and activated sludge is widely used for organic matter removal and electric energy recovery, the problem of high effluent nitrate still exists due to the lack of influent carbon source. Herein, a poly (butanediol succinate) (PBS) assembled MFC was established in an aerobic granular sludge (AGS) bioreactor for simultaneous promoting nitrogen removal and electricity generation. Compared to AGS-Control group, the total inorganic nitrogen (TIN) and COD removal efficiencies of AGS-MFC group were improved to 84.

Self-powered photoelectrochemical aptasensor based on AgInS@Co/Ni-UiO-66@CDs photoelectrode for estradiosl detection.

A self-powered photoelectrochemical (PEC) aptasensor was constructed to sensitively detect 17β-estradiol (E). Firstly, a reasonable AgInS@Co/Ni-UiO-66@Carbon Nanodots (CDs) photoelectrode with excellent photoelectrochemical performance was built by a simple two-step preparation method. The Co and Ni doping markedly improved the activity of UiO-66; the matched energy level of AgInS and Co/Ni-UiO-66 promoted the separation of electron-hole pairs, and the coupling of CDs further enhanced the conductivity and light utilization.

Self-powered Aptasensors Made with the InO-InS-TiC Composite for Dual-mode Detection of Microcystin-LR.

A dual-mode self-powered aptasensing platform of photoelectrochemical (PEC) and photofuel cell (PFC) was constructed for Microcystin-LR (MC-LR) detection. Specifically, the InO-InS-TiC (IO-IS-TC) composite was facilely assembled on the base of MOF-derived InO hollow tubulars, and the integrated mechanism and photoconversion efficiency are proposed and discussed in detail. Herein, a promising dual-mode sensing platform was constructed using the IO-IS-TC composite as a photoanode matrix with higher output power and obvious photocurrent response.

[Ru(bpy)]@Ce-UiO-66/Mn:BiS Heterojunction and Its Exceptional Photoelectrochemical Aptasensing Properties for Ofloxacin Detection.

A photoelectrochemical (PEC) aptasensor on basis of [Ru(bpy)]@Ce-UiO-66/Mn:BiS composites was constructed for detecting ofloxacin (OFL). First, Ce-UiO-66, prepared by a solvothermal method, had Zr-Zr and Ce-Ce intervalence cycles to increase the charge separation efficiency. Subsequently, Ce-UiO-66 was further modified by [Ru(bpy)] and Mn:BiS cosensitization to improve the photoelectric activity.

Self-powered photoelectrochemical aptasensor based on MIL-68(In) derived InO hollow nanotubes and Ag doped ZnInS quantum dots for oxytetracycline detection.

A self-powered photoelectrochemical (PEC) aptasensor was constructed based on MIL-68(In) derived indium oxide hollow nanotubes (InO HNs) and Ag-doped ZnInS quantum dots (QDs) as sensing matrix for the ultrasensitive detection of oxytetracycline (OTC). The hollow tube structure of the designed photoelectric active platform provided abundant active sites and a larger specific surface area for the immobilization of target recognition unit. The coupling of Ag:ZnInS QDs and InO HNs can accelerate the transmit and separation of photoinduced charge, and thus greatly increasing the intensity of photocurrent signal.

Synthesis of calcium-aluminum-layered double hydroxide and a polypyrrole decorated product for efficient removal of high concentrations of aqueous hexavalent chromium.

To efficiently remove high concentrations of hexavalent chromium (Cr(VI)), calcium-aluminum-layered double hydroxide (CaAl-LDH, denoted as CAL), and polypyrrole-modified CAL (CAL-PPy) were prepared by hydrothermal and in situ polymerization methods, respectively. The chemical structure, morphology, and elemental results indicated that the chain-like polypyrrole was decorated with hexagonal CAL. The specific surface area of CAL-PPy increased from 8.

A dual signal-amplified electrochemiluminescence immunosensor based on core-shell CeO-Au@Pt nanosphere for procalcitonin detection.

A dual signal-amplified sandwich electrochemiluminescence (ECL) immunosensor was fabricated for trace detection of procalcitonin (PCT). CeO-Au@Pt composed of sea urchin-like Au@Pt nanoparticles coated on CeO hollow nanospheres was immobilized on electrode surface to electrochemically catalyze HO to produce a large number of superoxide anion (O). The immunosensor was prepared by linking the capture antibody on immobilized CeO-Au@Pt with heptapeptide (HWRGWVC), which could maintain the activity of the antibody.

Microbial fuel cell enhanced pollutants removal in a solid-phase biological denitrification reactor: System performance, bioelectricity generation and microbial community analysis.

A novel electrochemical system of microbial fuel cell (MFC) coupled solid-phase denitrification biofilm reactor (DBR) system was established to explore the effect of simultaneous power generation and pollutant removal under different HRTs (Ⅰ:48 h; Ⅱ :24 h). The average removal rates of methyl orange, Cr (VI) and NO-N in test group were 93.0, 98.

Ultrafast and efficient removal of Pb(II) from acidic aqueous solution using a novel polyvinyl alcohol superabsorbent.

The direct removal of heavy metal ions from acidic wastewater is a hard problem. In this study, a novel superabsorbent, polyvinyl alcohol phosphate ester (PVAP), was designed and prepared to remove Pb(II) from acidic wastewater (pH = 3). The PVAP can absorb water and swell to reach equilibrium within 30 s, which provides the conditions for ultrafast kinetic adsorption.

Goethite/biochar-activated peroxymonosulfate enhances tetracycline degradation: Inherent roles of radical and non-radical processes.

While biochar supported iron materials have been widely studied in advanced oxidation processes (AOPs), little is known about the effect and mechanism of goethite/biochar in sulfate radical (SO) based AOPs. Herein, a novel goethite/biochar composite was applied as peroxymonosulfate (PMS) activator for tetracycline (TC) degradation in the water. The superior catalytic efficiency of goethite/biochar was achieved through radical (OH and SO) and non-radical (O) processes according to the radicals quenching experiments and electron paramagnetic resonance analysis.

Effective removal of Cu(II), Pb(II) and Cd(II) by sodium alginate intercalated MgAl-layered double hydroxide: adsorption properties and mechanistic studies.

To improve the adsorption efficiency of layered double hydroxides (LDHs) for heavy metals, a novel sodium alginate (SA) intercalated MgAl-LDH (SA-LDH) was synthesized in this work. SA-LDH was characterized by XRD, FTIR, XPS and employed as adsorbent for Cd(II), Pb(II), Cu(II) elimination. Adsorbent dosage, initial pH and contact time, which are regarded as several key parameters, were optimized.

Oxidative transformation of 1-naphthylamine in water mediated by different environmental black carbons.

Black carbons (BCs) are ubiquitous in the natural environment and can significantly influence the environmental behavior of pollutants. This work examined the mediating effects of graphite, soot, and biochar on 1-naphthylamine (1-NA) oxidation under aerobic conditions. It was shown that the three BCs significantly promoted the oxidation of 1-NA in the dark, and the mediation efficiency of graphite was much greater than that of soot or biochar.

Simultaneous nitrate and dissolved organic matter removal from wastewater treatment plant effluent in a solid-phase denitrification biofilm reactor.

In the present study, an up-flow solid-phase denitrification biofilm reactor (US-DBR) was established for simultaneous nitrate and dissolved organic matter (DOM) removal from wastewater treatment plant effluent. After 100 days operation, the nitrate and COD removal efficiencies were high of 97% and 80%, respectively. According to EEM-FRI analysis, aromatic and tryptophan protein-like, humic-like and fulvic acid-like substances were identified in DOM.

Efficient degradation of tetracycline by CoFeLa-layered double hydroxides catalyzed peroxymonosulfate: Synergistic effect of radical and nonradical pathways.

Advanced oxidation technologies based on peroxymonosulfate (PMS) have attracted increasing attention because of their high reactivity and selectivity. Herein, we reported a novel CoFeLa-LDH catalyst, which exhibited excellent performance to activate PMS for tetracycline (TC) elimination. The influence of extra addition, simulation wastewater tests and the reusability experiments were investigated in detail.

Phosphate adsorption performance and mechanisms by nanoporous biochar-iron oxides from aqueous solutions.

To evaluate the adsorption mechanism and performance of phosphate onto the composite of low-cost biochar and iron oxide, four biochar-iron oxides, namely biochar-magnetite (BC-M), biochar-ferrihydrite (BC-F), biochar-goethite (BC-G), and biochar-hematite (BC-H), were prepared by fabricating iron oxide to porous biochar. The biochar-iron oxides had huge surface areas of 691-864 m/g and average pore diameters of 3.4-4.

Aerobic biodegradation of p-nitrophenol in a nitrifying sludge bioreactor: System performance, sludge property and microbial community shift.

The system performance, sludge property and microbial community shift were evaluated in a nitrifying sludge (NS) bioreactor for simultaneous treating p-Nitrophenol (PNP) and high ammonia wastewater. After long-term acclimation for 80 days, the removal efficiencies of PNP and NH-N reached to 99.9% and 99.

Adsorption of heavy metals by l-cysteine intercalated layered double hydroxide: Kinetic, isothermal and mechanistic studies.

To understand the interaction mechanisms between heavy metals and functional groups modified nanomaterials, the l-cysteine (Cys) intercalated MgAl-layered double hydroxide (MgAl-Cys-LDH) was designed by a facile co-precipitation method and used to remove Cu(II), Pb(II) and Cd(II) in water solutions. The XRD, FTIR, SEM, TEM, EDS and XPS characterization analyses proved the carboxyl, thio and amido groups were successfully introduced into MgAl-LDH. The possible mechanisms were analyzed by the XPS and XRD spectra and involved the precipitation of metal hydroxides or sulfides, surface complexation with abundant surface groups, and the isomorphic substitution of Mg(II).

Adsorption and photocatalytic reduction of aqueous Cr(VI) by FeO-ZnAl-layered double hydroxide/TiO composites.

To evaluate the synergetic adsorption capacity of layered double hydroxide (LDH) and photocatalytic reduction property of TiO for aqueous Cr(VI), the FeO-ZnAl-LDH and TiO composites (FLT) were prepared via sol-gel method. The removal efficiency of FLT composites for Cr(VI) changed with the mass ratio of FeO-LDH/TiO, and the optimal ratio was 20% (FLT-2). The adsorption efficiencies of 100 mg FLT-2 were 74% and 64% for 20 and 50 mg/L Cr(VI) solution, and the total removal ratios of Cr(VI) were all over 97% after UV irradiation.