Recent advances in electrochemical decontamination of perfluorinated compounds from water: a review

● Recent advances in the electrochemical decontamination of PFAS are reviewed. ● Underlying mechanisms and impacting factors of these processes are discussed. ● Several novel couped systems and electrode materials are emphasized. ● Major knowledge gaps and research prospects on PFAS removal are identified. Per- and polyfluoroalkyl substances (PFAS) pose serious human health and environmental risks due to their persistence and toxicity. Among the available PFAS remediation options, the electrochemical approach is promising with better control. In this review, recent advances in the decontamination of PFAS from water using several state-of-the-art electrochemical strategies, including electro-oxidation, electro-adsorption, and electro-coagulation, were systematically reviewed. We aimed to elucidate their design principles, underlying working mechanisms, and the effects of operation factors (e.g., solution pH, applied voltage, and reactor configuration). The recent developments of innovative electrochemical systems and novel electrode materials were highlighted. In addition, the development of coupled processes that could overcome the shortcomings of low efficiency and high energy consumption of conventional electrochemical systems was also emphasized. This review identified several major knowledge gaps and challenges in the scalability and adaptability of efficient electrochemical systems for PFAS remediation. Materials science and system design developments are forging a path toward sustainable treatment of PFAS-contaminated water through electrochemical technologies.     

Pollutant decontamination by polyethyleneimine-engineered agricultural waste materials: a review

Environmental Chemistry Letters - The direct discharge of untreated contaminants into global water systems has jeopardized our water security worldwide. This environmental concern has prompted...     

Soil management for sustainable crop disease control: a review

Excessive use of agrochemicals in conventional crop management has caused serious environmental and health problems including loss of biodiversity and human disorders. A number of chemical biocides have shown complex chronic effects such as change in endocrine functions and immune systems. Application of different chemical biocides to the soil and plants have increased substantially over the last five decades. Total consumption of chemical fertilizers worldwide increased tenfold from 1950 to 2000. This is also true for chemical biocides with its annual current use of 3 billion l and a value of 30 billion dollars. There are ample evidences indicating that plants which grow in rich soil associated with N-P-K availability are prone to pests and diseases. Managing and exploiting soil environmental conditions as part of an integrated control strategy can make a significant contribution to agricultural sustainability and environmental quality. Application of organic matter and practises which increase the total microbial activity in the soil might enhance general suppression of pathogens by increasing competition for nutrients. Choice of crops in rotation with plants less susceptible to specific pathogens causes a decline in population due to natural mortality and the antagonistic activities of co-existent root zone microorganisms. Plants growing in disease-suppressive soil resist diseases much better than in soils with low biological diversity. Understanding the effect of soil environmental factors on plant disease incidence and the best crop management strategies to prevent, avoid, escape and control diseases were the aims of this literature review. This article comprises the main topics on soil fertility associated with N-P-K and other macro- and micro nutrients, and also soil pH, structure and texture, organic matter and microbial reserves, describes the use of various crop management practises which reduce the incidence of plant diseases.     

Chitosan-based beads as sustainable adsorbents for wastewater remediation: a review

Environmental Chemistry Letters - Water contamination is increasing worldwide, yet actual methods of water and wastewater treatment are limited, in particular by actual fossil-fuel derived...     

Biopolymer-supported TiO2 as a sustainable photocatalyst for wastewater treatment: a review

The rising water pollution by pesticides, pharmaceuticals and dyes is a major health issue calling for advanced remediation methods such as photocatalysis with titanium dioxide (TiO₂), yet the use of TiO₂ displays issues of aggregation, mass loss, recovery, and reusability. These issues have been recently solved by synthesizing biopolymer-supported photocatalysts using cheap, biodegradable and safe biopolymers such as chitosan, alginate, cellulose, cyclodextrin, guar gum and starch. Here we review biopolymer-supported TiO₂ photocatalysts for the removal of organic compounds, with focus on preparation methods, photo and chemical stability, reusability, and adsorptive capacity. We discuss applications of immobilized photocatalysts at the industrial scale.

     

Green technology for sustainable surface protection of steel from corrosion: a review

Plants contain substances that inhibit corrosion. Here we review biomass-based corrosion inhibitors from plant leaves, nuts, and fruit peels, after treatment with acids, bases or saline solutions. The mechanism of corrosion inhibition involves a monolayer coverage, according to isotherm and Langmuir models. Plant extract-based corrosion inhibitors contain heteroatoms whose electrons pair in the p-electron level in multiple bonds and the vacant d-orbitals of iron. Corrosion inhibition under marine conditions involves various chemical interactions between metals and dissolved ionic components.

     

Polymeric nanocomposite membranes for water treatment: a review

Environmental Chemistry Letters - Water scarcity is a pressing global challenge. Filtration with actual polymeric membranes shows good capability for pollutant separation, but broad applications of...     

Synthesis and application of titanium dioxide photocatalysis for energy,decontamination and viral disinfection: a review

Environmental Chemistry Letters - Global pollution is calling for advanced methods to remove contaminants from water and wastewater, such as TiO2-assisted photocatalysis.  The...     

Ecological engineering for water in sustainable settlements construction

The components of a water system in a settlement should benefit the residents, environment and nature. Ecological engineering for water use in settlements is crucial for designing and constructing a sustainable community. This article discusses ecological engineering measures and technology case studies in China for systematic regulation of the multiple functions of water in a sustainable community. These methods include reusing all sources of water (rainwater, wastewater and surface water), separating water that has been used for different purposes, promoting nutrient cycling, and improving the self-purification of water by controlling pollutant loads.     

Self-healing concrete for sustainable buildings. A review

Environmental Chemistry Letters - A total of 12 billion tons of concrete materials are produced annually, about 2 tons per person. More sustainable buildings are thus needed to decrease the carbon...     

Methods to prepare biosorbents and magnetic sorbents for water treatment: a review

Access to drinkable water is becoming more and more challenging due to worldwide pollution and the cost of water treatments. Water and wastewater treatment by adsorption on solid materials is usually cheap and effective in removing contaminants, yet classical adsorbents are not sustainable because they are derived from fossil fuels, and they can induce secondary pollution. Therefore, biological sorbents made of modern biomass are increasingly studied as promising alternatives. Indeed, such biosorbents utilize biological waste that would otherwise pollute water systems, and they promote the circular economy. Here we review biosorbents, magnetic sorbents, and other cost-effective sorbents with emphasis on preparation methods, adsorbents types, adsorption mechanisms, and regeneration of spent adsorbents. Biosorbents are prepared from a wide range of materials, including wood, bacteria, algae, herbaceous materials, agricultural waste, and animal waste. Commonly removed contaminants comprise dyes, heavy metals, radionuclides, pharmaceuticals, and personal care products. Preparation methods include coprecipitation, thermal decomposition, microwave irradiation, chemical reduction, micro-emulsion, and arc discharge. Adsorbents can be classified into activated carbon, biochar, lignocellulosic waste, clays, zeolites, peat, and humic soils. We detail adsorption isotherms and kinetics. Regeneration methods comprise thermal and chemical regeneration and supercritical fluid desorption. We also discuss exhausted adsorbent management and disposal. We found that agro-waste biosorbents can remove up to 68–100% of dyes, while wooden, herbaceous, bacterial, and marine-based biosorbents can remove up to 55–99% of heavy metals. Animal waste-based biosorbents can remove 1–99% of heavy metals. The average removal efficiency of modified biosorbents is around 90–95%, but some treatments, such as cross-linked beads, may negatively affect their efficiency.

     

Photoelectrochemical water splitting using post-transition metal oxides for hydrogen production: a review

Environmental Chemistry Letters - Dihydrogen (H2), commonly named ‘hydrogen,’ is considered as a promising renewable fuel that does not emit carbon dioxide upon combustion. Nonetheless,...     

Design of polymeric carbon nitride-based heterojunctions for photocatalytic water splitting: a review

Environmental Chemistry Letters - Developing high-efficiency and stable photocatalysts able to accomplish spontaneous overall water splitting, without using sacrificial agents, is the ultimate goal...     

Strategies to design modified activated carbon fibers for the decontamination of water and air

The rapid industrialization has induced the entry of organic and inorganic contaminants into the environment at a rate greater than environmental cleaning. As a consequence, pollutants have accumulated in environmental media, thus posing health risk for living organisms. Here, we present surface treatment strategies that modify physicochemical properties of activated carbon fibers for environmental remediation. In particular, we review metals, metal oxides and various advanced materials used for modifying activated carbon fibers. We discuss the utilization of modified activated carbon fibers for adsorption of organic pollutants and inorganic pollutants, and for the degradation of organic pollutants by photocatalysis, electrocatalysis, Fenton process and dielectric barrier discharge. We also discuss air pollutant removal, capacitive deionization, removal of inorganic ions and microbial decontamination by modified activated carbon fibers.     

Ecological accounting: new tools for a sustainable culture

Ecological accounting is concerned with providing information to assist managers with performance appraisal, control, decision-making and reporting for an organisation or region. It is based on ecological concepts and on ecological measures and values in addition to the familiar economics ones. The implementation of sustainable development requires a cultural change and ecological accounting would represent a part of this change within both organisations and wider society. In many ways, ecological accounting could help bring sustainable development into common sense and give it a place as a day-to-day business goal.     

Algae and bacteria consortia for wastewater decontamination and transformation into biodiesel,bioethanol, biohydrogen,biofertilizers and animal feed: a review

Traditional wastewater treatment has been aimed solely at sanitation by removing contaminants, yet actual issues of climate change and depletion of natural resources are calling for methods that both remove contaminants and convert waste into chemicals and fuels. In particular, biological treatments with synergic coupling of microalgae and bacteria appear promising to remove organic, inorganic, and pathogen contaminants and to generate biofuels. Here, we review the use of algae and bacteria in the treatment and valorization of wastewater with focus on cell-to-cell adhesion, wastewater properties, and techniques for algae harvesting and production of biodiesel, bioethanol, biohydrogen, exopolysaccarides, biofertilizers, and animal feeds.

     

Supported porphyrins for the photocatalytic degradation of organic contaminants in water: a review

Environmental Chemistry Letters - Porphyrins are differentiated π-conjugated compounds with unique photochemical and redox properties. The tetrapyrrole macrocycle core of porphyrins is...     

Electrochemical oxidation of azo dyes in water: a review

Environmental Chemistry Letters - Pollution of waters by azo dyes is a major global issue because some azo dyes have carcinogenic and mutagenic effects. Therefore, advanced methods are required to...     

Dyes removal from water using polymeric nanocomposites: a review

Environmental Chemistry Letters - Most dyes are pollutants that should be removed from waters due to their mutagenic and carcinogenic properties, requiring advanced adsorption methods. Here, we...     

Piezocatalytic removal of water bacteria and organic compounds: a review

Environmental Chemistry Letters - In the context of climate change, freshwater shrinkage and industrialization, human diseases are increasing due to water pollution by toxic chemicals and...