The oxidative degradation ability of peracetic acid (PAA) for organic pollutants can be enhanced by different activation methods. This study investigated the degradation efficiency and mechanisms of tetracycline (TC) using PAA activated by liquid-phase discharge plasma. An 86.08 % degradation efficiency for TC after 60 min treatment was achieved in the Plasma/PAA system, much higher than that of the sole Plasma (46.64 %) and PAA (15.19 %). Acidic conditions and neutral conditions were more favorable for TC removal than alkaline conditions. Inorganic ions generally inhibited TC degradation, though notably, low concentrations of Cl- and NO3- promoted it. Free radical quenching experiments and electron paramagnetic resonance (EPR) analysis confirmed the crucial roles of center dot OH, RO center dot , and 1 O 2 in TC degradation. Three-dimensional fluorescence spectroscopy (3DFS) and ultraviolet -visible absorption spectroscopy (UV -VIS) elucidated the TC degradation mechanism, revealing key aspects of antibiotic structural decomposition. Further analysis of the degradation products by liquid chromatography-mass spectrometry (LC-MS) indicated three potential degradation pathways. Biotoxicity evaluations indicated that the synergistic system significantly reduced the biotoxicity of the degradation products. This study demonstrated an efficient method for plasma-activated PAA in degrading persistent pharmaceutical pollutants. It also confirmed the system 's applicability across a broad spectrum of organic pollutants and water bodies, highlighting its potential for a wide range of environmental protection applications.

Low-temperature plasma technology has been successfully applied to the treatment of persistent organic pollutants in water. By combining catalysts with low-temperature plasma, the degradation efficiency and energy utilization efficiency of pollutants can be effectively improved. In this study, ferrocene (Fc) was added as a new catalyst to the low-temperature plasma system to treat tetracycline (TC) found in wastewater. The degradation efficiency of TC after 60 min of plasma treatment, Fc adsorption, and Fc/plasma treatment was compared, indicating that Fc/plasma improved the removal compared with using plasma alone. The effects of primary parameters such as Fc dosage, initial pH, discharge voltage, and anions in wastewater on TC removal efficiency were investigated. Under the conditions of Fc dosage of 400 mg/L, pH of 9, and discharge voltage of 20 kV, the degradation efficiency of TC was 76.59%. Results of free quenching experiments indicated that hydroxyl radicals played an important role in the treatment of TC. The characterizations of Fc showed that the structure of Fc before and after use in the plasma system changed little. In addition, toxicity testing using toxicity assessment software showed that only two to three degradation intermediate products had slightly higher toxicity than TC. The iron leaching concentration was 2.5 mg/L, and the Fc dissolution concentration was 1.72 mg/L after the reaction.

As a typical type of organic flocculant, chitosan is limited by its poor water solubility and narrow pH range application.

Indeed, the efficient and sustainable recovery of lithium from highly concentrated sodium-containing mother liquors of Li2CO3 and salt-lake brines remains a significant challenge. Herein, two typical Li+ recognition receptors, namely benzo-12-crown-4 and thenoyltrifluoroacetone, were separately introduced into the cationic and anionic parts to successfully synthesize novel bi-functionalized task-specific ionic liquids [(B12C4)Cnim][TTA] (n = 4, 6, 8). A new, green, and high-efficiency extraction system has been developed by dissolving [(B12C4) C6im][TTA] in commercial room-temperature ionic liquid 1-hexyl-3-methyl-imdazolium bis(trifluromethylsulfonyl)imide [C6mim][NTf2], without the addition of any other co-extractants. The newly developed [(B12C4)C6im][TTA]-[C6mim][NTf2] extraction system exhibited a wide pH working range (4.0-11.0), high lithium extraction efficiency (95.4 %), as well as superior separation factors of Li/Na ( beta Li/Na = 2154.0) and Li/K (beta Li/K=757.2). The extraction mechanism involving cation exchange was determined through slope analysis, ion chromatography, UV-vis spectroscopy and FT-IR spectra measurement, indicating that one [(B12C4)C6im] [TTA] molecule can interact with two lithium ions and form a 1:2 complex. Moreover, the [(B12C4)C6im][TTA]- [C6mim][NTf2] extraction system also demonstrated fast extraction kinetics, facile stripping and regeneration, along with good cycling performance. Furthermore, a multi-stage countercurrent extraction process to extract lithium from the simulated mother liquor of Li2CO3 was evaluated. When the volume ratio (O/A) of oil phase (O) to water phase (A) was 1.0, only two theoretical extraction stages were needed to extract 91.4 % of lithium into the organic phase. Thus, the [(B12C4)C6im][TTA]-[C6mim][NTf2] extraction system is promising for lithium extraction from mother liquor of Li2CO3 and salt-lake brines. This study also opens the avenue for designing cationic and anionic bi-functionalized ionic liquids for metal ion separation.

The acyl homoserine lactone (AHL)-based regulation strategy presents a considerable potential in improving anaerobic digestion (AD) efficiency of complex substrates. However, the reinforcement mechanisms are still unclear. In this study, the effects of different AHL types (C4-HSL, C7-HSL, C12-HSL) and different adding times (0 d, 5 d, 15 d) on AD performance of agricultural wastes (corn straw and cattle manure) were investigated. The results indicated that all types of AHLs exerted positive effects on AD, and the adding time rather than the AHL type was the key factor affecting AD processes. The C12-5d group obtained the highest accumulated methane production (310.7 +/- 2.56 mL/g VS), which increased by 47.71% than that of the Control group. The exogenous AHLs facilitated the hydrolysis and acidification of complex substrates and the utilization of released lowmolecular-weight organic acids in AD systems. Furthermore, the role of methanogenic archaea was upregulated and the dominance of bacteria was relatively weakened in AD systems, which favored the estab- lishment of their balanced and symbiotic metabolic relationship. The enriched Methanobacterium strengthened the hydrogenotrophic methanogenesis pathway. This study provides new insights into the regulation strategy of AD for agricultural waste treatment based on AHL addition.

The flocculation performance of chitosan can be enhanced by grafting modification to overcome its disadvantages of poor water solubility. In this study, chitosan was modified by dielectric barrier discharge plasma and polymerized with acrylamide and aluminum chloride to synthesize a new chitosan-based flocculant, namely, chitosan-acrylamide-aluminum chloride (CA-PAC). After optimizing the synthesis conditions of CA-PAC, the best conditions were as follows: discharge time of 3 min, discharge power of 50 W, polymerization temperature of 60 degrees C, polymerization time of 3 h, total monomer concentration of 100 g/L, and m(AlCl3):m(CA) ratio of 2:1. Characterization was performed through SEM, XPS, FTIR, XRD, TG and 1H NMR. Results showed that the preparation of CA-PAC was successful. The influences of flocculant dosage, pH, and stirring intensity on flocculation efficiency were investigated. The removal efficiency of turbidity was 94.1 %. The investigation of the flocculation mechanism revealed that CA-PAC mainly relied on charge neutralization or the synergic action of electric neutralization, bridging, and roll-sweep under acidic and neutral conditions, but it depended on the joint action of adsorption bridging and net sweeping under alkaline conditions. This study provides new ideas for the preparation and development of modified chitosan and broadens its application in water treatment.

Bioelectrochemical systems (BESs) are an emerging technology for wastewater treatment and resource recovery. These systems facilitate electron transfer between microorganisms and electrodes, enabling their application in various fields, such as electricity production, bioremediation, biosensors, and biocatalysis. However, electrode biofilms, which play a critical role in BESs, face several challenges (e.g., a long acclimation period, low attached biomass, high electron transfer resistance, and poor tolerance and stability) that limit the development of this technology. Quorum sensing (QS) is a communication method among microorganisms that can enhance the performance of BESs by regulating electrode biofilms. QS regulation can positively impact electrode biofilms by enhancing extracellular electron transfer (EET), biofilm formation, cellular activity, the secretion of extracellular polymeric substances (EPS), and the construction of microbial community. In this paper, the characteristics of anode electrogenic biofilms and cathode electrotrophic biofilms in BESs, EET mechanisms, and the main factors affecting biofilm formation were summarized. Additionally, QS regulation mechanisms for biofilm formation, strategies for enhancing and inhibiting QS, and the application of QS regulation for electrode biofilms in BESs were systematically reviewed and discussed. This paper provides valuable background information and insights for future research and development of BES platforms based on QS regulation of electrode biofilms.

The degradation of phenol by pulsed discharge plasma above a liquid surface（APDP） and under a liquid surface（UPDP） was compared. The effects of discharge voltage, discharge distance,initial solution conductivity and initial p H on the removal of phenol were studied. It was concluded that the removal of phenol increases with increasing discharge voltage and with decreasing discharge distance in both APDP and UPDP systems. An increase in the initial solution’s conductivity has a positive effect in the APDP system but a negative effect in the UPDP system. In addition, alkaline conditions are conducive to the degradation of phenol in the APDP system, while acidic conditions are conducive in the UPDP system. Free radical quenching experiments revealed that ·O-2has an important influence on the degradation of phenol in the APDP system, while ·OH plays a key role in the UPDP system. This paper verifies the differences in the two discharge methods in terms of phenol removal.

In recent years, non-thermal plasma technology as an advanced oxidation process has received increasing attention for wastewater treatment. In previous studies, the discussion about the effects caused by different metal electrodes in the plasma treatment system is limited. In this work, phenol degradation efficiency and H2O2 formation with Al, Ti, Fe, Ni, Cu, W, and Mo electrodes were investigated. The use of Fe, Ni, and Al electrodes results in higher phenol removal, than that using W, Cu, Mo, and Ti electrodes. After 70 min of discharge treatment, phenol was continuously decomposed in the solution in the Fe, Cu, and Mo electrodes systems. High peak voltage promoted phenol degradation and H2O2 generation, especially for Fe, Ti and Ni electrodes. The alkaline condition is more conducive to phenol degradation than the neutral and acidic conditions regardless of the electrode type. Fe, Al, Cu, and Ni electrodes are affected more by the adjustment of the conductivity with Clthan that with SO42 � . The dominant influence on H2O2 production and decomposition could be attributed to the catalysis of metal particles and metal ions produced by electrode erosion. According to the radical quenching experiments, the main radicals in the degradation of phenol when using each electrode material were analyzed.