Pd/γ-MnO2/Ni foam cathode for efficient electrocatalytic hydrodechlorination of chlorophenols in aqueous solution and wastewater.

Enhanced removal of sulfur-containing organic pollutants from actual wastewater by biofilm reactor: Insights of sulfur transformation and bacterial metabolic traits

A comprehensive review highlights the photocatalytic heterojunctions and their superiority in the photo-destruction of organic pollutants in industrial wastewater

There has been a recently increasing interest in homogeneous electro-Fenton technology for the remediation of organic pollutants in water streams. In the electro-Fenton process, organic compounds are oxidized by direct electrolysis on the anode in the electrolytic cell based on the generation of a very powerful oxidizing agent, such as the hydroxyl radical (•OH) in a solution. This chapter presents a review on the fundamentals and realistic application of electro-Fenton as an effective degradation process for complex organic pollutants in wastewaters. The classification of this technique, along with the effect of influencing factors such as current density, concentrations of H2O2, Fe2+, anions, etc. are also discussed in this chapter. In addition, the existing challenges and the most important techniques for eliminating complex aqueous organic pollutants in industrial wastewaters are discussed.

Fabrication of a permeable SnO2-Sb reactive anodic filter for high-efficiency electrochemical oxidation of antibiotics in wastewater.

Coupling photocatalytic water oxidation on decahedron BiVO4 crystals with catalytic wet peroxide oxidation for removing organic pollutions in wastewater

Preparation and synergistically enhanced supercapacitance properties of MnO2-PANI/Ti foam composite electrodes

Coking wastewater has a complex and highly concentrated chemical composition which is toxic and does not biodegrade easily. Treating the organic pollutants in this wastewater is very challenging. The toxic substances in this wastewater make traditional biotechnological treatments inefficient. Current wastewater treatment studies are based on unit processes, and no full process studies could be found. This study used the micro-nanometer catalytic ozonation process as a pretreatment unit, and reverse osmosis membrane treatment as a depth processing unit to improve the effect of the coking wastewater degradation. The micro-nanometer catalytic ozonation pretreatment greatly improves the biodegradability of the coking wastewater and promotes the coking wastewater degradation in the anoxia/anaerobic/oxic (A/A/O) system. The integrated coagulation air flotation-micro-nanometer catalytic ozonation-A/A/O-reverse osmosis membrane system can remove 98% of the chemical oxygen demand, which meets the direct emission standard of the new national standard (China). The dominant genera in the A/A/O biochemical reactor were Thioalkalimicrobium, Proteiniphilum, Azoarcu, Bacillus, Fontibacter, and Taibaiella. This work provides a novel approach for the degradation of high-concentration organic wastewater and lays a solid foundation for the restoration of environmental water bodies.

Butene isomerisation catalyst

China is the world’s largest producer of acrylic fiber, and the wastewater generated from its production contains a significant amount of biologically refractory organic pollutants. However, comprehensive screening studies on organic compounds in such wastewater remain limited, which hampers effective wastewater treatment and ecological risk management to some extent. In this study, high-resolution mass spectrometry (HRMS) was combined with comprehensive two-dimensional gas chromatography (GC×GC) and ultra-performance liquid chromatography, along with multiple characterization techniques—including proton nuclear magnetic resonance spectroscopy, infrared spectroscopy, and fluorescence spectroscopy—to qualitatively analyze organic compounds present in wastewater from four stages of wet-spun acrylic fiber production: acrylonitrile mixed wastewater, polymerization wastewater, spinning wastewater, and final mixed wastewater. The results indicated that sulfonate esters, various other esters, alkanes, heterocyclic compounds, aromatic compounds, and substances containing multiple conjugated systems were commonly present across all four sample types, potentially contributing to the poor biodegradability of the wastewater. Additionally, a higher abundance of volatile organic compounds was detected in the mixed wastewater, while acrylonitrile appeared to be more concentrated in the spinning wastewater. The complementary use of spectral analysis, proton nuclear magnetic resonance, and HRMS provided a robust analytical foundation for identifying organic pollutants in acrylic fiber production wastewater.

Persistent organic pollutants (POPs) in wastewater pose significant environmental and health risks due to their toxicity, persistence, and bioaccumulation. Conventional treatment methods often struggle to effectively remove these pollutants, necessitating the development of advanced technologies. Cerium-based photocatalytic nanocomposite membranes have emerged as a promising solution, combining the benefits of physical separation and photocatalytic degradation. This review provides a comprehensive analysis of the advancements in cerium-based photocatalytic membranes for wastewater treatment, focusing on their composition, synthesis methods, photocatalytic properties, and applications. The incorporation of cerium dioxide (CeO 2 ) nanoparticles into membranes enhances hydrophilicity, porosity, and separation performance, with optimal loading levels of 2–3 wt.% demonstrating significant improvements in mechanical properties and water flux. The photocatalytic efficacy of these membranes is influenced by factors such as nanoparticle size, morphology, surface area, and the incorporation of additional materials like graphene oxide or metal oxides. Cerium-based photocatalytic membranes have achieved pollutant removal efficiencies exceeding 95% for a wide range of contaminants, including dyes, antibiotics, oils, and heavy metals. However, challenges such as the wide bandgap of CeO 2 , scalability issues, and long-term stability concerns need to be addressed for successful industrial implementation. Future perspectives highlight the potential of hybrid nanocomposites, metal and non-metal doping, morphology control, and advanced heterojunction construction to enhance the performance and sustainability of cerium-based photocatalytic membranes for wastewater treatment applications.

Efficient and Stable Carbon-coated Nickel Foam Cathodes for the Electro-Fenton Process

Organic pollutants in wastewater are the biggest problem facing the world today due to population growth, rapid increase in industrialization, urbanization, and technological advancement. There have been numerous attempts to use conventional wastewater treatment techniques to address the issue of worldwide water contamination. However, conventional wastewater treatment has a number of shortcomings, including high operating costs, low efficiency, difficult preparation, fast recombination of charge carriers, generation of secondary waste, and limited light absorption. Therefore, plasmonic-based heterojunction photocatalysts have attracted much attention as a promising method to reduce organic pollutant problems in water due to their excellent efficiency, low operating cost, ease of fabrication, and environmental friendliness. In addition, plasmonic-based heterojunction photocatalysts contain a local surface plasmon resonance that enhances the performance of photocatalysts by improving light absorption and separation of photoexcited charge carriers. This review summarizes the major plasmonic effects in photocatalysts, including hot electron, local field effect, and photothermal effect, and explains the plasmonic-based heterojunction photocatalysts with five junction systems for the degradation of pollutants. Recent work on the development of plasmonic-based heterojunction photocatalysts for the degradation of various organic pollutants in wastewater is also discussed. Lastly, the conclusions and challenges are briefly described and the direction of future development of heterojunction photocatalysts with plasmonic materials is explored. This review could serve as a guide for the understanding, investigation, and construction of plasmonic-based heterojunction photocatalysts for various organic pollutants degradation.Graphical abstractHerein, the plasmonic effects in photocatalysts, such as hot electrons, local field effect, and photothermal effect, as well as the plasmonic-based heterojunction photocatalysts with five junction systems for the degradation of pollutants are explained. Recent work on plasmonic-based heterojunction photocatalysts for the degradation of various organic pollutants in wastewater such as dyes, pesticides, phenols, and antibiotics is discussed. Challenges and future developments are also described.

The purpose is to optimize the catalytic performance of biochar (BC), improve the removal effect of BC composites on organic pollutants in wastewater, and promote the recycling and sustainable utilization of water resources. Firstly, the various characteristics and preparation principles of new BC are discussed. Secondly, the types of organic pollutants in wastewater and their removal principles are discussed. Finally, based on the principle of removing organic pollutants, BC/zero valent iron (BC/ZVI) composite is designed, among which BC is mainly used for catalysis. The effect of BC/ZVI in removing tetracycline (TC) is comprehensively evaluated. The research results reveal that the TC removal effect of pure BC is not ideal, and that of ZVI is general. The BC/ZVI composite prepared by combining the two has a better removal effect on TC, with a removal amount of about 275 mg/g. Different TC concentrations, ethylene diamine tetraacetic acid (EDTA), pH environment, tert-butanol, and calcium ions will affect the TC removal effect of BC composites. The overall effect is the improvement of the TC removal amount of BC composites. It reveals that BC has a very suitable catalytic effect on ZVI, and the performance of BC composite material integrating BC catalyst and ZVI has been effectively improved, which can play a very suitable role in wastewater treatment. This exploration provides a technical reference for the effective removal of organic pollutants in wastewater and contributes to the development of water resource recycling.

Nanoporous gold (NPG) films were fabricated on Ni foam substrates via a two-step procedure which involves electrodeposition of Au–Sn alloy films on the Ni foam surface, followed by selectively leaching the Sn component through a chemical dealloying process. Pd nanoparticles were then electrochemically deposited on the NPG/Ni foam electrode. The morphology of the Pd-decorated NPG/Ni foam composite electrode (Pd@NPG/Ni foam) was characterized by scanning electron microscopy (SEM). The catalytic activity of the Pd@NPG/Ni foam composite electrode toward H2O2 electroreduction in acid media was evaluated by means of linear scan voltammetry and chronoamperometry. The Pd@NPG/Ni foam composite electrode exhibited high activity and excellent stability for the H2O2 electroreduction, generating a current density of 178 mA cm−2 at 0 V in a 0.5 M H2SO4 + 0.6 M H2O2 electrolyte, in comparison to 98 mA cm−2 on the Pd@Ni foam electrode and 36 mA cm−2 on the NPG/Ni foam electrode. The developed three-dimensional (3D) hierarchical porous Pd@NPG/Ni foam can therefore be considered as a promising type of electrode for fuel cell applications.

Unraveling kinetics and mechanism of electrocatalytic hydrodechlorination of chlorinated PPCPs by nickel-cobalt metal organic framework supported palladium composite electrode