Isotope Techniques in Chemical Wastewater Treatment: Opportunities and Uncertainties.

A comprehensive and in-depth analysis of reaction mechanisms is essential for advancing chemical water treatment technologies. However, due to the limitations of conventional experimental and analytical methods, the types of reactive species and their generation pathways are commonly debatable in many aqueous systems. As a highly sensitive diagnostic tool, applications of isotopes as tracers and reactive probes offers deeper insights than conventional methods with minimal interference from reaction conditions.

Whether peracetic acid-based oxidation process is an alternative to the traditional Fenton process in organic pollutants degradation and actual wastewater treatment?

Industrialization has exerted significant adverse effects on water quality, leading to an increasing demand for environmentally friendly and high-efficiency technologies. The traditional Fenton process has been recognized as a viable method for treating challenging industrial wastewater. Recently, peracetic acid (PAA)-based advanced oxidation processes (AOPs) have emerged as a promising Fenton-like technology for efficient wastewater treatment.

Fluoride ions enhanced cobalt ferrite for peroxymonosulfate activation with efficient performance and active oxygen yield regulation.

The activation of peroxymonosulfate (PMS) by cobalt-based catalysts for the degradation of organic pollutants has been widely studied, while the role of coexisting anions has received little attention. In this study, the performance of atrazine (ATZ) degradation by the addition of fluoride ions (F) in the activation of PMS by cobalt ferrite (CoFeO) was investigated. The addition of F to the CoFeO/PMS system increased ATZ degradation effect from 82 % to 98 % within 10 min, and the rate increased from 0.

N-doped carbon nanotubes encapsulated NiZnC nanoparticles catalyst for peroxymonosulfate activation: Heterojunction structure and N-doping enhance electron transfer capability.

In this paper, a type of N-doped carbon nanotube-coated NiZnC metal nanoparticle heterostructure catalyst (NZC-C-700) was prepared by two-step roasting method and applied to depredate bisphenol A (BPA) with peroxymonosulfate (PMS) activation. Characterizations and first principles calculation (DFT) reveal that the heterostructure formed by the graphite carbon layer and NiZnC metal nanoparticles, coupled with various N doping, can effectively modulate surface charge distribution, which could improve charge transfer capability between the catalyst and PMS. Meanwhile, the results of quenching experiments, electron paramagnetic resonance (EPR) and chronoamperometry proposed that the system is a typical singlet oxygen (O) -dominated non-radical pathway.

Electron transfer tuning for persulfate activation via the radical and non-radical pathways with biochar mediator.

Electron mediator-based in-situ chemical oxidation (ISCO) offers a novel strategy for groundwater remediation due to diverse reaction pathways. However, distinguishing and further tuning the reaction pathway remains challenging. Herein, biochar as an electron mediator targeted active peroxysulphate (PDS) via the radical or non-radical pathway.

Activation of persulfates on carbon nanotubes for water decontamination: Is the non-radical process consistently considered across different pH levels?

Carbon nanotubes-driven persulfates oxidation processes (CNTs/PS) have been extensively studied for environmental remediation. Solution pH is one of the main factors affecting wastewater treatment, but it is often overlooked. Herein, we report the effect laws of pH on the mechanism of peroxymonosulfate (PMS) or peroxydisulfate (PDS) activation by CNTs.

Switchable surface Fe sites for water/sediment remediation through enhanced selective oxidation and ROS regulation: Performance, mechanism and application.

Selective oxidation relying on high-valent iron-oxo species (Fe(IV/V)) is a promising way of effective organic decontamination. However, Fe(IV/V) formation and further purposeful reinforcement production are commonly insufficient and unsustainable. Herein, cerium (Ce) modification strategy was adopted for efficient micropollutants removal through boosting Fe(IV/V) generation.

Activation of PAA at the Fe-N Sites by Boron Nitride Quantum Dots Enhanced Charge Transfer Generates High-Valent Metal-Oxo Species for Antibiotics Degradation.

Advanced oxidation processes (AOPs) based on peracetic acid (PAA) offer a promising strategy to address antibiotic wastewater pollution. In this study, Fe-doped graphitic carbon nitride (g-CN) nanomaterials were used to construct Fe-N sites, and the electronic structure was tuned by boron nitride quantum dots (BNQDs), thereby optimizing PAA activation for the degradation of antibiotics. The BNQDs-modified Fe-doped g-CN catalyst (BNQDs-FCN) achieved an excellent reaction rate constant of 0.

Cobalt doped g-CN activated peroxymonosulfate for organic pollutant degradation: Alterations in cobalt species and reactive oxygen species.

Cobalt-based materials are promising catalysts for activating peroxymonosulfate (PMS) to degrade organic pollutants. Among various cobalt-based catalysts, the alteration in cobalt species and the reactive species produced are not fully understood. Herein, four materials were synthesized by controlling synthesis methods and doping of g-CN to regulate cobalt species.

Self-cleaned surface of vanadium boride for long-lasting and boosted Fenton oxidation.

Coupling extra electron supply with iron-mediated advanced oxidation processes (AOPs) is an efficient strategy for long-lasting oxidation of organic contaminants in environmental remediation. Many subsequent attempts have been made, such as homogeneous catalysts and metal catalysts, of which secondary organic pollution and surface passivation layers limit their application. In this work, metal borides as co-catalysts can efficiently accelerate the Fenton reaction by firmly sacrificing electrons to Fe(III) reduction.

Influence of S(IV) reduction on the reaction mechanisms and the generation of reactive oxygen species in B-Cu@Fe/PPS system.

Heterogeneous sulfite-based advanced oxidation process is extremely promising for the removal of various industrial pollutants owing to its generation of multiple reactive oxygen species (ROS), while the unclear mechanism of S(IV) conversion and ROS generation hinder its practical applications. Here, the iron-copper bimetallic was synthesized for potassium pyrosulfate catalysis, which was designed for insight into the mechanism of micropollutant degradation driven by sulfur species conversion. Experimental and theoretical calculations have shown that the reaction process and corresponding mechanisms can be significantly distinguished into three different stages.

Revealing the essence of anion ligands in regulating amorphous MnOx to activate peracetic acid for micropollutant removal.

How the anion ligands of manganese precursors affect the catalytic activity of amorphous manganese oxides (MnOx) in Fenton-like process is poorly understood. Here, five amorphous MnOx synthesized by Mn(II) precursors with different ligands were characterized and adopted to activate peracetic acid (PAA) for bisphenol A (BPA) degradation. Although > 90 % BPA removal was achieved in the five MnOx/PAA processes via both adsorption and oxidation, the oxidation k greatly differentiates by the ligands types with the order of MnOx-N > MnOx-S > MnOx-Cl > MnOx-AA > MnOx-OA.

Comprehensive Insight into the Common Organic Radicals in Advanced Oxidation Processes for Water Decontamination.

Radical-based advanced oxidation processes (AOPs) are among the most effective technologies employed to destroy organic pollutants. Compared to common inorganic radicals, such as OH, O, and SO, organic radicals are widespread, and more selective, but are easily overlooked. Furthermore, a systematic understanding of the generation and contributions of organic radicals remains lacking.

MIL-125-PDI/ZnInS Inorganic-Organic S-Scheme Heterojunction With Hierarchical Hollow Nanodisc Structure for Efficient Hydrogen Evolution from Antibiotic Wastewater Remediation.

Efficient photocatalytic production of H from wastewater is expected to address environmental pollution and energy crises effectively. However, the rapid recombination of photoinduced carriers results in low photoconversion efficiency. At present, inorganic-organic S-scheme heterojunction have become a prominent and promising technology.

N-coordinated iron sites dispersed in porous carbon frameworks to activate peroxymonosulfate for efficient sulfisoxazole degradation and real hospital wastewater decontamination.

Herein, an N-coordinated Fe site dispersed in porous carbon frameworks (Fe-NC) fabricated from zeolitic imidazolate frameworks encapsulated with iron acetylacetonate (Fe(acac) @ZIFs) was employed to activate peroxymonosulfate (PMS) for the attenuation of sulfisoxazole (SIZ) and treating real hospital wastewater. The constructed Fe-NC/PMS system exhibited good catalytic stability for SIZ degradation, maintaining excellent degradation performance over multiple cycles with virtually no leaching. The quenching experiments, electron paramagnetic resonance (EPR) capture analyses, and semi-quantitative measurements showed that singlet oxygen (O) and high-valent metal-oxo species were mainly responsible for SIZ degradation by Fe-NC/PMS.

Rapid and efficient removal of organophosphorus pollutant and recovery of valuable elements: A boosted strategy for eliminating organophosphorus from wastewater.

Considering the significant hazards of organophosphorus compounds (OPs) and the potential crisis of phosphorus (P) resource shortage, there is a great necessity to develop economically feasible, highly effective, and sustainable strategies to remove OPs and recover P resources. In this study, low-cost microscale zero-valent iron (mZVI) was used to activate hydrogen peroxide for the rapid and efficient elimination of Tetrakis(hydroxymethyl)phosphonium sulfate (THPS) from the aquatic environment. Compared to the conventional Fenton reaction and commercial mZVI, mZVI/HO-based Fenton-like reaction exhibited superior removal performance for THPS.

Overlooked Complexation and Competition Effects of Phenolic Contaminants in a Mn(II)/Nitrilotriacetic Acid/Peroxymonosulfate System: Inhibited Generation of Primary and Secondary High-Valent Manganese Species.

Organic contaminants with lower Hammett constants are typically more prone to being attacked by reactive oxygen species (ROS) in advanced oxidation processes (AOPs). However, the interactions of an organic contaminant with catalytic centers and participating ROS are complex and lack an in-depth understanding. In this work, we observed an abnormal phenomenon in AOPs that the degradation of electron-rich phenolics, such as 4-methoxyphenol, acetaminophen, and 4-presol, was unexpectedly slower than electron-deficient phenolics in a Mn(II)/nitrilotriacetic acid/peroxymonosulfate (Mn(II)/NTA/PMS) system.

Long-range interactions driving neighboring Fe-N sites in Fenton-like reactions for sustainable water decontamination.

Actualizing efficient and sustainable environmental catalysis is essential in global water pollution control. The single-atom Fenton-like process, as a promising technique, suffers from reducing potential environmental impacts of single-atom catalysts (SACs) synthesis and modulating functionalized species beyond the first coordination shell. Herein, we devised a high-performance SAC possessing impressive Fenton-like reactivity and extended stability by constructing abundant intrinsic topological defects within carbon planes anchored with Fe-N sites.

Advanced Characterization Techniques and Theoretical Calculation for Single Atom Catalysts in Fenton-like Chemistry.

Single-atom catalysts (SACs) have attracted extensive attention due to their unique catalytic properties and wide range of applications. Advanced characterization techniques, such as energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy, and X-ray absorption fine-structure spectroscopy, have been used to investigate the elemental compositions, structural morphologies, and chemical bonding states of SACs in detail, aiming at unraveling the catalytic mechanism. Meanwhile, theoretical calculations, such as quantum chemical calculations and kinetic simulations, were used to predict the catalytic reaction pathways, active sites, and reaction kinetic behaviors of SACs, providing theoretical guidance for the design and optimization of SACs.

Ecological risk assessment methods for oxidative by-products in the oxidation degradation process of emerging pollutants: A review.

The inherent toxicity and persistence of emerging contaminants such as antibiotics and endocrine disruptors pose substantial threats to the environment. Advanced oxidation processes (AOPs) employed for oxidative degradation could yield toxic oxidation by-products (OBPs), including organic acids and aromatic hydrocarbons. Despite their typically low concentrations, OBPs require scrutiny owing to their potential health risks.

Hydroxylamine-induced activation of permanganate for enhanced oxidation of sulfamethoxazole: Mechanism and products.

Recently, many reagents have been introduced to accelerate the formation of highly reactive intermediate Mn species from permanganate (KMnO), thereby improving the oxidation activity of KMnO towards pollutants. However, most studies have mainly focused on sulfur-containing reducing agents (e.g.

One-step fabrication of a self-driven point-of-care chip by femtosecond laser direct writing and its application in cancer cell HO detection via semiconductor-based SERS.

Self-driven microfluidic systems have attracted significant attention and demonstrated great potential in the field of point-of-care (POC) testing due to their device simplicity, low power consumption, increased portability, and reduced sample consumption. To develop POC detection chips with diverse characteristics that meet different requirements, there is a strong demand for feasible strategies that enable easy operation and reduce processing time. Here, a one-step processing approach using femtosecond laser direct writing technology was proposed to fabricate a capillary-actuated POC microfluidic chip.