Raghunath Satpathy

Advances in Environmental Engineering and Green Technologies • 2021

The halogenated hydrocarbons have been widely used by human beings. They are xenobiotic and toxic. The microbes having a specific group of hydrolase enzymes, known as dehalogenases, that actually break the carbon-halogen bonds of the halogenated substances and subsequently convert them into their non-toxic forms. In this chapter, the categories of dehalogenase enzymes possessed by microorganisms are narrated. The overall source, mechanism of catalysis, and structural aspects of the haloalkane dehalogenase enzymes have been discussed with special focus to the bioremediation of 1, 2 dichloroethane.

Haozhe Zheng

Highlights in Science, Engineering and Technology • 2022

With the growing problem of oil seepage from gas stations around the world, remediation of oil-contaminated soils is receiving increased attention. Microbial electrochemical techniques have been shown to remove hydrocarbons from soil. Microbial fuel cells (MFC) show a strong potential to immobilize and dissipate contaminants using microorganisms. In this context, this review briefly introduces the conventional methods for remediation of petroleum soil contamination, focusing on the effects of different factors and configurations on the effectiveness of MFC remediation. Compared to traditional remediation methods, applying MFC to petroleum leaks in gas stations has better environmental and economic benefits. It does not require the application of chemicals or ex situ remediation of the soil, which largely reduces the cost and does not cause secondary pollution to the surrounding environment such as soil or atmosphere. In the long term, this technology has a good potential to enhance the remediation effect by changing the applied electric field, soil texture, and petroleum degrading bacteria. In addition, making soil MFC simultaneously achieve combined remediation of petroleum hydrocarbons and other contaminants remains to be studied. Finally, this paper emphasizes that there are few practical applications about MFC site remediation and there is a need to conduct site tests with large scale. If the pilot-scale tests are similar to the laboratory-scale treatment results, the technology will gain more popularity.

Mohd Faheem Khan

Processes • 2025

Fluorinated xenobiotics, such as per- and polyfluoroalkyl substances (PFAS), fluorinated pesticides, and pharmaceuticals, are extensively used across industries, but their extreme persistence, driven by the high carbon–fluorine (C–F) bond dissociation energy (~485 kJ/mol), poses serious environmental and health risks. These compounds have been detected in water, soil, and biota at concentrations from ng/L to µg/L, leading to widespread contamination and bioaccumulation. Traditional remediation approaches are often costly (e.g., EUR >100/m3 for advanced oxidation), energy-intensive, and rarely achieve complete degradation. In contrast, microbial defluorination offers a low-energy, sustainable alternative that functions under mild conditions. Microorganisms cleave C–F bonds through reductive, hydrolytic, and oxidative pathways, mediated by enzymatic and non-enzymatic mechanisms. Factors including electron donor availability and oxygen levels critically influence microbial defluorination efficiency. Microbial taxa, including bacteria, fungi, algae, and syntrophic consortia, exhibit varying defluorination capabilities. Metagenomic and microbial ecology studies continue to reveal novel defluorinating organisms and metabolic pathways. Key enzymes, such as fluoroacetate dehalogenases, cytochrome P450 monooxygenases, reductive dehalogenases, peroxidases, and laccases, have been characterised, with structural and mechanistic insights enhancing the understanding of their catalytic functions. Enzyme engineering and synthetic biology tools now enable the optimisation of these enzymes, and the design of microbial systems tailored for fluorinated compound degradation. Despite these advances, challenges remain in improving enzyme efficiency, broadening substrate specificity, and overcoming physiological constraints. This review emphasises the emerging promise of microbial defluorination as a transformative and green solution, uniquely integrating recent multidisciplinary findings to accelerate the development of sustainable microbial defluorination strategies for effective remediation of fluorinated xenobiotics.

Arunima Nayak, Brij Bhushan

Advances in Environmental Engineering and Green Technologies • 2021

Rapid industrialization, urbanization, and use of modern agricultural practices have resulted in the rise in pollutant levels in soil. In this context, nano-bioremediation has emerged as a new tool for controlling soil pollution by the application of nanomaterials with subsequent use of bioremediation. Due to its cost-effectiveness, eco-friendliness, and sustainability, the use of bioremediation in soil reclamation has rapidly gained prominence. Nanomaterials have helped in remediating toxic soil environments, thereby improving microbial activity and bioremediation efficiency. The overall time as well as costs are greatly reduced. The major limitation of this technology is its longer treatment time and its ineffectiveness for a wide range of pollutants. The chapter has an aim to present an overview of the recent advances and applications in the field of nano-bioremediation of various polluted areas of the environment. Different classes of nanomaterials along with their properties as well as application towards removal of soil pollutants will be addressed.

Rupesh Dutta Banik, Pritha Pal, Sibashish Baksi

Journal of Survey in Fisheries Sciences • 2023

Meeting environmental regulations for both liquid and solid wastes are produced during the manufacture of leather items is one of the long-term issues facing the leather industry. Insufficient treatment of these wastes will cause environmental pollution and endanger human health. Trimmings have generally been underutilized among other trash that are produced. Hair is not utilized, however collagen found in trims and garbage. Many organic and inorganic particles together with the discharge of suspended or gas-solid oil and grease, nitrogen-containing compounds, and heavy metals either by themselves or in their reduced salt form, chlorides, sulphates, chemical oxygen demand (COD) and total dissolved solids (TDS) are all considerably generated and influenced by tanning operations. Formaldehyde used in the production of finished leather that are difficult to biodegrade and can cause the production of free formaldehyde, a recognized carcinogen. Microbial bioremediation is a novel technique that may be used in a variety of soil and water environments due to microorganisms' adaptability to remove hazardous pollutants that could offer a safer and affordable strategy. The pollution profile of leather industries, microbial bioremediation for pollution reduction from diverse ecological lattices and interactions between the microbes and contaminants has received substantial attention in this review.

Himanshi Verma, Meghna Jindal, Shabir A. Rather

Advances in Environmental Engineering and Green Technologies • 2021

The soil is a repository of microorganisms such as bacteria, fungi, algae, and protozoa. Among these, more bacteria are found, most of which are located in the rhizosphere region of the soil. The rhizosphere, under the direct control of plant root secretions, is the complex, narrow area of the soil. It is densely populated with microorganisms (mostly bacteria) that interact with the plants. These interactions influence the growth of the plant directly or indirectly. Plant growth-promoting rhizobacteria (PGPR) inhabiting the rhizosphere colonizes the plant roots and increases plant growth via different mechanisms. Iron is an essential micronutrient required by almost all life forms including plants. Oxidation of Fe2+ (soluble) to Fe3+ (insoluble) due to the soil's aerobic conditions limits its bioavailability. Siderophores are selective low molecular weight ferric ion chelators secreted by bacteria to acquire iron from the surrounding. They bind to iron (Fe3+) with high specificity as well as high affinity. By helping the insolubilisation of iron, it promotes the growth and yield.

Rajalakshmi Sridharan, Veena Gayathri Krishnaswamy

Advances in Environmental Engineering and Green Technologies • 2021

Industrialization led to an increase in chemicals in the environment. The soil absorbs these chemicals and holds them for years until treated. The action of bacteria, fungi, and algae utilize the pollutants and generate energy. The bioremediation contains a diverse treatment process, but the effectiveness of the bioremediation increases by the enzymatic action. Laccase, a copper-containing enzyme, is versatile and oxidizes complex organic compounds without generating reactive oxygen species (ROS). This process is carried by laccase-mediated systems (LCMs) controlled by low redox potential. The presence of redox mediators oxidizes the chemical compounds at the higher rate, making laccase degradation of the pollutants effectively. The chapter provides a glimpse of soil bioremediation by bacteria and fungi as individual species and symbiotic species, the production of laccase enzyme by bacteria and fungi, methods adopted to enhance the enzyme activity, and degradation of pollutants in soil.

Arpitha Chikkanna, Devanita Ghosh

Research Anthology on Emerging Techniques in Environmental Remediation • 2022

Microorganisms play very important role in elemental and mineral chemistry on earth surface. Along with the major biogeochemical cycles such as Carbon, Nitrogen, Sulphur and Phosphorus, which are crucially involved in thermodynamic balances in earth system, microbes are also involved in trace metal cycling. The organic carbon sustaining the indigenous microbial communities critically controls these microbial processes. A large number of the microbial communities are able to form a wide variety minerals, of which many have only biogenic origin and cannot be formed inorganically. Microbes also play a critical role in dissolution of minerals; a process which not only helps in soil formation and the transport of nutrients to higher trophic levels, but can also have many important industrial roles. Thus, in these metabolic activities, microorganisms contribute to the geological phenomenon of the transformation of metals and minerals. This chapter focuses on the role of various microbial metabolic processes that are involved in mineralization and mineral dissolution and the consequences involved with it.

Md. Idrish Raja Khan

Advances in Environmental Engineering and Green Technologies • 2021

Mycoviruses are obligate parasites of fungi and can infect the majority of the fungal groups. They remain mysterious to various communities throughout the globe. Mycoviruses are responsible for certain changes in fungal hyphae, which could be asymptomatic and may cause a reduction or elimination of the virulence capacity of fungal hosts by the process called hypovirulence. Such fungal-virus system could be valuable for the development of novel biocontrol approaches against fungal pathogens for the development of a sustainable environment. There are adequate reports where mycovirus has been employed as a biocontrol approach against the pathogenic fungi in the fields of agriculture and other allied sciences. The prime focus of this review is to emphasize naturally available mycoviruses and strategies to adopt the mycovirus therapy which could serve as an excellent alternative strategy against chemical prophylactic and therapeutic approaches.

Ruiyi Qu

Theoretical and Natural Science • 2024

Abstract. Soil pollution is a global environmental problem that poses a threat to ecological balance and human health. Microbial soil remediation is an eco-friendly technology that utilizes microorganisms to degrade or transform soil pollutants. Due to some drawbacks of traditional soil remediation methods, microbial remediation method has become a hot research topic nowadays. In recent years, the development of genomics analysis technology has greatly promoted the progress of microbial remediation research, and the use of genomics approach is free from the technical constraints of traditional research and can efficiently obtain the relative abundance of microbial communities and other information. In this paper, we reviewed the application of genomics in microbial soil remediation, and discussed the genomic analysis of several examples of heavy metal contaminated soil remediation, which provides a reference for researchers to quickly screen analytical methods in the field of microbial soil remediation, and reveals the biological significance of genomics analytical techniques.

Avni Jain, Neha Singh, Suphiya Khan

Advances in Environmental Engineering and Green Technologies • 2021

The demand for the development of eco-friendly, sustainable, and adaptable technologies for the disinfection of the environmental contaminants is increasing nowadays. Nano-bioremediation is one such technique that has made possible the use of biosynthetic nanoparticles for soil pollution remediation. It is an effective, efficient, and feasible method for revitalizing soil potential and rendering it pollution free. Pollutants present in soil are a great threat to soil biota, environment, and in fact human health. Nanomaterials exhibit the unique chemical and physical properties because of which they have always received attention in the growing era of bioremediation. Use of nanotechnology for bioremediation is one such technology as it focuses mainly on the interaction between the contaminants, the microorganisms, and the nanomaterials being used for both the positive (i.e., stimulating) and negative or toxic environmental effects. Thus, this chapter focuses on the need to recover the polluted soil and application of nano-remediation technology for restoring soil's cultivation capacity.

Amrendra Kumar, Swati Agarwal

Advances in Environmental Engineering and Green Technologies • 2021

Microbial products are being used from ages in known as well as unknown forms. Some common products harvested from microbes include proteins, amino acids, antibiotics, antibodies, secondary metabolites, organic acids, lipids, and so on. It also includes antivirals, polymers, surfactants, enzyme inhibitors, nutraceuticals, and many industrial and agricultural products. Moreover, sometimes the whole single celled microbes are harvested as a rich source of protein called single cell proteins. In a nutshell, all these products cover almost every economic sector like food, feed, agriculture, healthcare, fuel, textile, and pharmaceutical. Hence, these microbial products have serious socio-economic impressions and have unleashed enormous possibilities in terms of commercial production. However, only a small fraction of microbial products are exploited, and a larger chest remains to be achieved. In the chapter, the importance of microbes in the production of proteins, enzymes, and secondary metabolites are discussed in detail with special emphasis on sustainable agriculture.

R. Gayathri, J. Ranjitha, V. Shankar

Bioremediation for Environmental Pollutants • 2023

Chemical elements with an atomic mass unit ranging from 63.5 – 200.6 (relative atomic mass) and a relative density exceeding 5.0 are generally termed as heavy metals. Since they are non-biodegradable inorganic contaminants, physical and chemical methods of degradation are ineffective. Heavy metals cannot be degraded easily due to their physical and chemical properties, such as the rate of oxidation & reduction reactions, rate of solubility, formation of complexes with other metal ions, etc. They are flexible, and easily accumulated in the environment. In the case of bioaccumulation, they are highly lethal to the organisms. The process of removal of toxic and hazardous material from the environment using plants and microorganisms is termed bioremediation. The disposal of toxic contaminants using plants is termed phytoremediation. Microbial bioremediation consists of the removal of toxic elements with the application of microorganisms during which the toxic substance is converted into either end products or nontoxic and non-hazardous forms or recovery of metals. <br>

Junqia Kong, Zhibin He, Chen Longfei et al.

• 2021

Lacking of systematic evaluations in soil quality and microbial community recovery after different amendments addition limits optimization of amendments combination in coal mine-soils. We performed a short-term incubation experiment over 12 weeks to assess the effects of three amendments (biochar: C; nitrogen fertilizer at three levels: N-N1~N3; microbial agent at two levels: M-M1~M2) based on C/N ratio (regulated by biochar and N level: 35:1, 25:1, 12.5:1) on soil quality and microbial community in the Qilian Mountains, China. Over the incubation period, soil pH and MBC/MBN were significantly lower than unamended treatment in N addition and C+M+N treatments, respectively. Soil organic carbon (SOC), total nitrogen (TN), available nitrogen (AN), available phosphorus (AP), available potassium (AK), microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) contents had a significant increase in all amended treatments (P<0.001). Higher AP, AK, MBC, MBN and lower MBC/MBN were observed in N2-treated soil(corresponding to C/N ratio of 25:1). Meanwhile, N2-treated soil significantly increased species richness and diversity of soil bacterial community (P<0.05). Principal coordinate analysis further showed that soil bacterial community compositions were significantly separated by N level. C-M-N treatments (especially at N2 and N1 levels) significantly increased the relative abundance (>1%) of the bacterial phyla Bacteroidetes and Firmicutes, and decreased the relative abundance of fungal phyla Chytridiomycota (P<0.05). Redundancy analysis illustrated the importance of soil nutrients in explaining variability in bacteria community composition (74.73%) than fungal (35.0%). Our results indicated that N and M addition based on biochar can improve soil quality by neutralizing soil pH and increasing soil nutrient contents, and the appropriate C/N ratio (25:1: biochar+N2-treated soil) can better promote mass, richness and diversity of soil bacterial community. Our study provided a new insight for achieving restoration of damaged habitats by changing microbial structure, diversity and mass by regulating C/N ratio of amendments

Shenaz Sultana Ahmed, Popy Bora

bioRxiv (Cold Spring Harbor Laboratory) • 2023

ABSTRACT Growing brinjal ( Solanum melongena L.) in a soil polluted with organophosphorus pesticide (OP) residues coupled with an additional threat of wilt disease caused by Ralstonia solanacearum ( Rs ), pose a formidable management challenge for residue free crop production. Our study aimed at identifying efficient OP-degrading bacteria (OPDB) and their compatibility with microbial bio-control agents (MBCA) for twin objective of microbial degradation of OP -residues and reduction in incidence of bacterial wilt of brinjal in OP-contaminated soil. As many, ten bacterial isolates showing OP-degrading potential were recovered through colony growth in mineral salt (MS) - medium treated with 25 ppm chlorpyriphos. Efficient isolates displaying growth up to 700ppm chlorpyriphos were further screened for OP-degradation, leading to identification of two most efficient OPDB, Acromobacter marplatensis [MW397524] ( Am ) and Pseudomonas azotoformans [MW397525] ( Pa ). These two isolates having in vitro compatibility with each other, showed further compatibility with two most widely used MBCA, viz., Pseudomonas flourescens [KT258013] ( Pf ) and Trichoderma harzianum [ON364138] ( Th ), facilitating the development of consortium having extended functional corridor. The response of combination of OPDB + MBCA( Am + Pa + Pf + Th ) showed 80% lower percent wilt incidence (PWI), 2.8 times higher fruit yield of brinjal, and 15-25% lower OP-residues over un-inoculated control treatment. Our studies, hence, put forward a strong unified delivery mechanism of OPDB and MBCA as a part of green technology for chemical residue -free vegetable production in contaminated soils. IMPORTANCE Microbes isolated from crop rhizospheres are known to exhibit multiple functions (plant growth promotion, antagonism against soil borne pathogens e.g., Rs, and acaricidal properties) depending upon type of stimuli by regulating the plant defense. Considering the limited past efforts on twin objective of cleaning up the pesticide residues accumulated in the soil (microbial removal of pesticide residues) and providing an additional safeguard against soil borne pathogen causing bacterial wilt in brinjal to collectively develop a microbial consortia mediated crop production system, devoid of any chemical residues. Such an effort adds strength to organic production system on pesticide contaminated soils. In the present study, we succeeded in identifying two most effective chloropyrifos residues degrading OPDB having compatibility two MBCA for developing consortia formulation, which aided in developing pesticide residue free soil, neutralising bacterial wilt pathogen ( Rs ), and creating a better nutrient supply for a well deserved production system. Such efforts would pave the way for developing more robust microbial formulations (with emphasis on entomopathogenic application) having dynamic microbial functions to replace any futuristic use of agrochemcials.

G‐Y. Rhee, Y‐C. Cho, E.B. Ostrofsky

Remediation Journal • 1999

Abstract The extent of natural dechlorination varies widely in sediments and fails to reach its maximum potential. Recent laboratory and field studies have suggested that the potential for further dechlorination is low in the Hudson and St. Lawrence Rivers. Laboratory investigations have also indicated that polychlorinated biphenyl (PCB) dechlorination is directly coupled to the growth of dechlorinating microorganisms in that: (a) there was no growth of dechlorinating microorganisms below the threshold concentration, (b) the rate of chlorine removal per gram sediment was significantly correlated to the growth rate of the microorganisms, (c) the negative effect of lower moisture levels on dechlorination was correlated to the microorganism death rate, and (d) the extent of natural dechlorination in the St. Lawrence River appears to be related to the in‐situ population size of dechlorinators. There also appear to be many dechlorinating populations, each with different requirements and competence. Therefore, the growth enhancement of these microorganisms is the key to promoting PCB dechlorination either in situ or ex situ. © 1999 John Wiley & Sons, Inc.

Kumud Dubey, K. P. Dubey

Advances in Environmental Engineering and Green Technologies • 2021

Bauxite residue (red mud) is an industrial waste bye product of Alumina industry. It is toxic and highly alkaline in nature having heavy metals. Its disposal is the paramount environmental issue in Alumina industry. In the present study, bioremediation of red mud was carried out through cyanobacteria amendments and plantation. Two cyanobacterial species (viz. Phormidium and Oscillatoria) were found promising after studying their effect on physico-chemical characteristics of red mud. Seeds of selected tree species (viz. Dalbergia sissoo, Prosopis juliflora, Acacia auriculiformis, Pithecellobium dulce, Cassia siamia) were procured, and a nursery of these tree species was raised. Performances of two cyanobacteria (viz. Phormidium and Oscillatoria sps.) in combinations with PSB and VAM on red mud are very encouraging and hold considerable promise for bioremediation and revegetation of red mud. Inoculated seedlings of P. juliflora, P. dulce, A. auriculiformis, and C. siamia performed well for red mud revegetation.

Elze Hesse, Daniel Padfield, Florian Bayer et al.

bioRxiv (Cold Spring Harbor Laboratory) • 2018

Abstract In an era of unprecedented environmental change, there have been increasing ecological and global public health concerns associated with exposure to anthropogenic pollutants. While there is a pressing need to remediate polluted ecosystems, human intervention strategies might unwittingly oppose selection for natural detoxification, which is primarily carried out by microbes. We test this possibility in the context of a ubiquitous chemical remediation strategy aimed at targeting toxic metal pollution: the addition of lime-containing materials. Here we show that raising pH by liming decreased the availability of toxic metals in acidic mine-degraded soils, but as a consequence selected against microbial taxa that naturally remediate soil through the production of metal-scavenging siderophores. Understanding the ecological and evolutionary consequences of human intervention on key traits is crucial for the engineering of evolutionary resilient microbial communities, having important implications for human health and biotechnology.

Turna Dutta

Journal of Survey in Fisheries Sciences • 2023

Antibiotics are compounds that are natural as well as synthetic and semi-synthetic. They show various activities that are antimicrobial in nature. This group of medicines is one of the most successful ones in their usage. In nations that are developing, antibiotics have emerged as a boon. But along with this came a curse. The antibiotics are not completely degraded within the body. The indigested portion comes out into the environment, causing the pollution of antibiotics. Already chemicals, so the usage of chemicals to get rid of such pollution is another hazard. In this review, we have discussed the removal of such antibiotic pollution from various sources like households, hospitals, agricultural fields, and other such places with the help of biological organisms, primarily microorganisms. Bioremediation is a quite common term in the present day, and one of the most effective ones. The microbes either break the chemicals into non-toxic elements or use that as their energy sources and thus, the harmful effect of the compounds gets reduced. The focus of the present review helps us to analyze antibiotics and their bioremediation.

Anna Poshtarenko

E3S Web of Conferences • 2021

The process of purification and disinfection of yeast production sewage under the action of electrodialysis has been studied. As a result of research to determine the physicochemical and microbiological sewage composition, it was found that in sewage of the 1st degree of yeast separation has the highest excess content of organic and mineral substances in terms of: Chemical oxygen consumption (COC) - 31096/500 mg О2 / dm3, suspended solids - 6800 / 300 mg / dm3, chlorides - 2147/350 mg / dm3and sulfates - 6089/400 mg / dm3. The content of organic substances, which is characterized by the Chemical oxygen consumption (COC) indicator, in sewage of general discharge, 2nd and 3rd degree of yeast separation is 41%, 50% and 74% and that is lower than in sewage of the 1st degree of yeast separation. The number of microorganisms in terms of Total microbial count (TMC) in sewage of the 1st stage of yeast separation is the largest and is 12·107 colony-forming units CFU / cm3. It is determined that the process of sewage treatment and disinfection from minerals occurs more efficiently in the cathode zone, and from organic substances and microorganisms - in the anode zone of the electrodializer at a water temperature of 293 K, current of 0.1 A and duration of exposure 20 min.

Jonghun Lim

ECS Meeting Abstracts • 2024

The escalating presence of nitrogen pollutants in urine wastewater poses a significant environmental challenge. Among the array of methods available to tackle this issue, electrochemical oxidation processes that produce reactive chlorine species (RCS) from readily available chloride ions appear as a promising solution. Despite the investigation of various anode materials, current options continue to face challenges such as low selectivity in generating reactive chlorine species (RCS), instability, and significant energy consumption. This study investigated iridium-doped tin oxide (Ir-SnO 2 ) as an efficient, stable, and energy-saving anode for RCS-mediated treatment of urine wastewater. The Ir-SnO 2 anode surpassed counterparts like IrO 2 SnO 2 and Sb-SnO 2 , showcasing its superior electrochemical performance marked by high current density, minimal charge transfer resistance, and a significant active surface area. Additionally, it attained outstanding current efficiency of 91.7% and energy efficiency of 7.79 mmol Wh -1 for generating reactive chlorine species (RCS) at 30 mA cm –2 in a diluted 0.1 M chloride solution. Density functional theory (DFT) calculations corroborated experimental findings, indicating that the introduction of Ir to SnO 2 boosts chlorine adsorption by altering the electronic structure, thereby reducing overpotential and enhancing electrocatalytic activity for chlorine evolution reactions. Ir-SnO 2 also showcased impressive effectiveness in removing ammonia nitrogen, total nitrogen, and chemical oxygen demand, achieving efficiencies of 100%, 97.8%, and 89.1%, respectively. These outcomes rivaled those attained by IrO 2 (dimensional stable anode, DSA), surpassing the performance of the boron-doped diamond (BDD) anode. Additionally, Ir-SnO 2 demonstrated the lowest energy consumption compared to benchmark DSA and BDD anodes when treating urine wastewater. In stability evaluations, the Ir-SnO 2 electrode maintained a stable anodic cell potential for 100 hours of continuous electrolysis in a 0.1 M NaCl electrolyte and remained operational over five cycles without any signs of deactivation.

Aicheng Chen

ECS Meeting Abstracts • 2024

The contamination of water with a myriad of pollutants has become an increasingly global issue in recent decades due to the widespread expansion of industrialization, which has tremendously propagated the development of large-scale industries and increased metallurgic production. Water contamination is anticipated to increase at least two-fold over the next 20 years. In this talk, a new design of an integrated electrode is introduced for the photo-electrochemical purification of water from a wastewater treatment plant. A nanoporous TiO 2 structure, directly grown on a Ti substrate by anodization, and a RuO 2 -IrO 2 -based electrode was utilized as the photocatalyst and the electrocatalyst, respectively. Photocatalytic and electrocatalytic activities were synergistically combined to achieve an integrated and highly catalytically active electrode. Our experimental results have shown that the efficient enablement of photocatalytic and electrocatalytic activities within a single integrated electrode may be achieved via the new design. The applicability of this integrated electrode system was also tested in a pilot plant at a local water treatment facility. The pilot plant testing results revealed that much more efficient removal of organic waste was accomplished using the integrated electrode system as compared to only photocatalyst or electrocatalyst. The synergistic effect of the integrated bi-functional electrodes will be discussed.

Wang Yun-Hai, Kuang Jun-Yao

Journal of Advanced Oxidation Technologies • 2013

Abstract Nickel and antimony doped tin dioxide (NATO) coated titanium electrodes were used for electrochemical treatment of oilfield produced wastewater. The effects of electrode distance, current density and electrolysis time on COD removal ratio, current efficiency, energy efficiency and BOD to COD ratio were investigated. The optimized electrode distance of 5 mm and current density of 6 mA cm

Kajal Gautam, Yatindra Kumar, Shriram Sonawane et al.

Research Square • 2024

Abstract In the present study, electrochemistry based electro-coagulation (EC) process, as a green approach is used for the decolorization of Reactive Blue 4 (RB4) from simulated wastewater. A multivariate approach, response surface methodology (RSM) and central composite design (CCD) is employed to model and optimize the EC process with five input variables (pH, initial concentration of dye, current density, operating time, and electrodes gap) to treat the wastewater containing RB4 dye. The efficiency of EC process is calculated in terms of % decolourization and chemical oxygen demand (COD) removal. A back-propagation Artificial Neural Network (BP - ANN) is also engaged to predict the % colour and % COD removal. The experimental values of %decolourization (89.3%) and COD removal (84.3%) are found very close to predicted %decolourizations (88.6% and 89.4%) and COD removal (83.4% and 84.4%) at optimized conditions [pH ( X 1 ) = 7.0; initial dye concentration ( X 2 ) = 1297.6 mgL -1 ; current density ( X 3 ) = 13.42 mAcm -2 ; contact time ( X 4 ) = 70 min and initial electrodes gap ( X 5 ) = 1.0 cm] using RSM and ANN, respectively. Techno-economic efficacy is determined in terms of an operating cost as Rs. 114.82 m -3 . The physico-chemical properties of the EC process generated sludge are analyzed using FTIR and FESEM/EDX. The comparative analysis with previous studies and future perspectives of the EC process for the removal of RB4 from wastewater is also carried out.

Rui Zhao, Wenqiang Jiang

MATEC Web of Conferences • 2018

Nicosulfuron, a kind of sulfonylurea herbicide, because of its high activity and low dosage, has been widely used in corn planting weeding. Electrochemical method was chosen to treat its simulated waste water and the influence factors such as current intensity, plate spacing and electrolyte pH on electrolysis effect were investigated. A double-coated titanium dioxide titanium plate was chosen as the anode accompanied with a single-coated titanium plate as the cathode. The results showed that the removal efficiency of nicosulfuron was the highest when the electrolyte pH=3, the plate spacing is 1.5cm and the current intensity is 0.8A. Under the optimal condition, the removal rate of nicosulfuron reached 86.6% after 7 hours electrolysis. Thus, electrochemical technology might provide a significant method to remove the synthetic organic compounds.

Georgios Bampos, Georgia Antonopoulou, Zacharias Frontistis

Processes • 2025

Global population growth, combined with the energy-intensive demands of modern lifestyles, has led to a significant increase in energy demand, accompanied by the ongoing environmental burden due to the dependence on fossil fuels [...]

Byeong-ju Kim, Hyunwoong Park

ECS Meeting Abstracts • 2020

The configuration of the hybrid electrochemical desalination system with ion exchange membranes is presented. Ion exchange memebranes (anion exchange membrane, cation exchange membrane) was alternately inserted into the system chambers and induce electrochemical desalination with transport of anions and cations toward the anode (nano-TiO2) and cathode (Bi-foam), respectively. Simultaneously, reactive chlorine species (RCS) was produced with the anodic reaction of chloride ion supplied by its transport from the desalination chamber. the produced reactive chlorine species initiated decomposition reaction of urea in anolyte. the Bi-foam cathode converted the dissolved carbon dioxide into formate, the simplest carboxylate anion with one carbon atom. the Faradaic efficiency of formate production was >95%. Additionally, small solar panel (0.5 x 3.5 cm2, 4 V) was wired to examine the solar-to-formate energy efficiency of the hybrid electrochemical desalination system. More details of experiment results will be presented and discussed.

Shan Shao, Jason Chun-Ho Lam

ECS Meeting Abstracts • 2024

Wastewater treatment is an essential process for the sustainable development of a society. The handling and degrading of different refractory and toxic organic pollutants heavily relies on conventional biodegradation. Herein, we developed an electrochemical hydrogenation method to enhance the biodegradability of organic substrates, which subsequently improves their availability to existing biological-driven denitrification, a key step that turned NO 3 - into harmless N 2 . The strategy presents an unprecedented "kill-two-birds-with-one-stone" method to simultaneously deal with excessive organic components, aka. Chemical Oxygen Demand (COD), and nitrate's presence in wastewater. The strategy was discovered by comparing the biodegradability of some organic compounds and their hydrogenation forms. It was found that the hydrogenation product was much more bioavailable. Motivated by this discovery, we synthesized a carbon-supported Ru electrode by electrodepositing Ru on activated carbon cloth (ACC), named Ru/ACC. After that, 4-chlorophenol was used to optimize the experimental conditions, and Ru/ACC electrodes successfully converted 99.9% of 4-chlorophenol with an overall yield reached 90.9%. After that, the Ru/ACC electrodes proved efficient in transferring various wastewater organic pollutants. Besides, the electrochemical hydrogenation effect on biochemical degradation and denitrification was studied. Our electrochemical treatment was significant for the electrochemical hydrogenation method to be applied to wastewater treatment.

Sudeep Popat, Ao Xie

ECS Meeting Abstracts • 2019

Microbial electrochemical cells (MECs) are devices in which anaerobic treatment of wastewater can occur in the anode chamber, where anode-respiring bacteria oxidize fatty acids produced from fermentation of waste organics to produce an electrical current. MECs are best suited for high-strength industrial wastewater streams, rather than dilute domestic wastewater streams. We have evaluated the possibility of using MECs for treatment of rendering wastewater, which contains high concentrations of fats (and often also proteins). We first conducted biochemical methane potential (BMP) tests to determine the anaerobic biodegradability of rendering wastewater (COD concentrations of ~7000 mg/L), and to determine optimum organic loading rate (relative to biomass concentration). Using the optimum conditions, we then conducted batch MEC studies to determine maximum current densities that could be produced, as well as the COD removal and conversion efficiencies. Maximum current densities of up to 2.5 A/m 2 were produced, while COD conversion to electrical current ranged between 70-80%. Our studies indicate that MECs could become suitable for treatment of high fat content wastewater streams.

Ya Feng Li, Yuan Han Duan

Advanced Materials Research • 2011

The simulant wastewater containing high concentration ammonia-nitrogen was treated by electro-chemical oxidation process in intermittent experiment. The influences of different factors including plate distance,current density, chloride ion concentration and initial pH on ammonia-nitrogen and total nitrogen removal were studied.According to the results of the test, the optimal reaction condition was determined as follows: plate distance was 40mm，current density was 90mA/cm2，chloride ion concentration was 8000mg/L, initial pH was 10。Under the above condition,the total nitrogen concentration reduced from 2000 mg/Lto 280mg/L when the reaction time was 8h, and the removal rate reached 86%. As we can see, the effect of the treatment is quite positive.

Feng Tao Chen, San Chuan Yu, Xing Qiong Mu et al.

Advanced Materials Research • 2012

The Ti/SnO 2 -Sb 2 O 3 /PbO 2 electrodes were prepared by thermal decomposition method and its application in the electrochemical degradation of a heteropolyaromatic dye, Methylene blue (MB), contained in simulated dye wastewater were investigated under mild conditions. The effects of pH, current density and electrolysis time on de-colorization efficiency were also studied. Chemical oxygen demand (COD) was selected as another parameter to evaluate the efficiency of this degradation method on treatment of MB wastewater. The results revealed that when initial pH was 6.0, current density was 50 mA·cm 2 , electrolysis time was 60 min, Na 2 SO 4 as electrolyte and its concentration was 3.0 g·dm 3 , the de-colorization and COD removal efficiency can reach 89.9% and 71.7%, respectively.

Dzmitry Malevich, Sreeman Mypati, Sreemoyee Ghosh Ray et al.

Research Square • 2024

Abstract Cathode materials based on carbon substrates are of high interest for the electrochemical generation of hydrogen peroxide (H 2 O 2 ) for wastewater treatment because of their low cost, chemical stability and high selectivity. However, the H 2 O 2 selectivity of carbon materials can be significantly reduced in presence of surfactants, which are frequent contaminants in wastewater. Therefore, the development of surfactant-tolerant cathode materials is highly important. In this paper, composite electrodes comprising of polytetrafluoroethylene and carbon black on a carbon felt substrate were prepared. The effect of sodium dodecyl sulphate on the electrode activity was investigated. It was found that the electrodes prepared with high bulk density carbon black featured a high H 2 O 2 Faradaic efficiency of 95% in surfactant-free solutions. These electrodes also showed significant surfactant tolerance having a 70% Faradaic efficiency in the presence of 1mM sodium dodecyl sulphate. The enhanced surfactant tolerance is attributed to the hydrophobic properties of the electrode surface.

Jiachao Yao, Sini Lv, Zeyu Wang et al.

Research Square • 2021

Abstract Electro-oxidation is a promising technology for wastewater treatment with bio-refractory organic and nitrogen pollutants; however, the high energy-demanding hinders its wide application. In this study, a novel method by regulating the significant parameter during electro-oxidation process timely for actual dyeing wastewater treatment with energy saving was studied. Operating factors (i.e., flow rate, initial pH value, electrode distance, and current density) were investigated for chemical oxygen demand (COD) and ammonia removal, and results indicated that current density was the key factor which obviously influenced the electrochemical performance. Indirect oxidation by active chlorine was then confirmed as the main reaction pathway for pollutants oxidation, and the relationship between the current density and the generation of active chlorine was established, suggesting that a large part of the generated active chlorine was not utilized effectively. Subsequently, a novel method by variation of current density timely based on the reaction mechanism was proposed; results indicated that, with similar pollutant removal efficiency, energy consumption could be reduced from 31.6 kWh/m 3 to 20.5 kWh/m 3 . Additionally, the novel system was further optimized by Box-Behnken design: COD and ammonia removal efficiencies could reach 71.8% and 100% respectively, and energy-demanding could be reduced by 45.6%.

Maasoomeh Jafari, Gerardine G. Botte

ECS Meeting Abstracts • 2020

Solid waste mismanagement causes environmental contamination. Sewage sludge is the byproduct of the wastewater treatment process and contains pathogenic organisms (e.g Salmonella spp., Escherichia coli, etc.). Anaerobic digestion is widely used for sewage sludge treatment. However, the major drawback of this process is the sluggish rate of sludge biodegradation. Therefore, the retention time in the typical digester is long (between 20-30 days) which consequently results in substantial energy consumption. On the other hand, approximately 50- 60 % of the operational cost in the wastewater treatment plant is dedicated to the treatment and disposal of waste. Hence, it is essential to develop a treatment method to decrease energy consumption. Alkaline treatment is an attractive process for sludge destruction and improvement in the sludge biodegradability. Furthermore, electrochemical oxidation of the organic materials is an environmentally friendly alternative pathway to disintegrate the sludge microbial cells and eliminate the pathogen bacteria from biosolid for safe disposal. Therefore, the combined alkaline electrochemical technique could expedite waste degradation by using the synergetic functions and increase efficiency of the treatment. To overcome the challenges related to the conventional treatment method, our research group has developed a novel, energy-efficient mixed alkali-electrochemical sludge treatment in a membraneless electrochemical system at room temperature and low applied potential. In this study, the bimetallic (platinum-iridium) nanocatalyst was synthesized with modified polyol method. The thermal behavior of the raw sludge and the residue biosolid after electrolysis was evaluated by using thermogravimetric analysis (TGA). To determine the effect of electrolysis on the chemical structure of biosolid, the Fourier-transform infrared spectroscopy-Attenuated Total Reflection (FTIR-ATR) and elemental analysis techniques were applied. Ammonia was produced as a byproduct of the waste treatment which can be converted to hydrogen through electrolysis. A considerable amount of solid reduction was achieved by implementing a short electrolysis treatment which diminished the waste transportation and disposal cost to a large extend. Furthermore, the energy consumption was significantly lower than the previous research studies. In this presentation, results from this study including (i) the electrochemical performance of catalyst for sewage sludge treatment (ii) pathogen disinfection and (iii) biosolid characterization will be provided.

Gisela C. Régis, Edério D. Bidoia

Holos Environment • 2006

The treatment of chemical industry wastewater by an electrochemical method was investigated using steel and TiRuO2 electrodes. Visible-UV spectrophotometric analyses have been performed in samples electrolyzed at 0, 10, 20, 30 and 40 min to determine the molecular changes in the wastewater. Although the steel electrode caused changes in molecules present in the raw effluent, the TiRuO2 electrode showed to promote more significant changes. It has been observed an increase in the cellular viability after electrolysis; this could be a decrease in the biological toxicity after the treatment. The electrolytic process is an efficient method to modify persistent molecules, normally, found in wastewater of rubber chemical industry and, turn then biocompatible to the environment.

Mohammadreza Nazemi

The Electrochemical Society Interface • 2022

This project will address the critical bottleneck in electrochemical redox processes (i.e., decreasing cost and improving efficiency) for wastewater treatment and resource recovery by developing cost-effective and selective electrode materials that can treat or valorize ROC for safe discharge or reuse. The overarching goal is to develop an electrochemical prototype to degrade a wide range of organic contaminants, minimize electrodes’ fouling and scaling, and recover valuable resources (e.g., metals and salts), contributing to achieving “pipe parity” and “circular economy” using small-scale and modular electrochemical water treatment systems.

Lingjie Xu

Theoretical and Natural Science • 2025

Electrochemical technology has demonstrated significant advantages in water pollution treatment by virtue of its efficient redox reaction and flexible control characteristics. This paper systematically discusses the principles and applications of electrocoagulation (EC), electrooxidation (EO) and electro-flotation (EF): electro-flocculation generates hydroxide colloid adsorption of pollutants through the dissolution of the metal anode, and the removal rate of heavy metals (Pb, Cd, Cu) reaches more than 98%; electro-oxidation degrades difficult-to-biodegrade organics with the help of hydroxyl radicals (-OH), and the removal of dyestuff wastewater can reach over 98%. Electro-oxidation with the help of hydroxyl radicals (-OH) to degrade difficult-to-degrade organic matter, the COD and color removal rate of dyestuff wastewater is more than 80%; Electro-flotation using micro-bubbles to achieve high-efficiency separation of emulsified oils and colloidal particles. The synergistic process (e.g., EC-EF) can remove heavy metals and organics simultaneously, and the reduction rate of chromaticity and COD of printing and dyeing wastewater reaches 92.9% and 88.9%, respectively. However, the high cost of electrodes, high energy consumption and scale-up bottlenecks constrain its development. In the future, we need to focus on the development of low-cost electrode materials, multi-technology coupling (e.g., electrochemical-photocatalytic) and intelligent control, in order to promote electrochemical technology in the direction of zero industrial wastewater discharge and resource transformation, and help the sustainable management of water pollution.

, Yasir AlJaberi Forat

Azerbaijan Chemical Journal • 2025

Population demands are leading to an increase in the dumping of wastewater from domestic and industrial activities worldwide. Electrochemical oxidation (EO) has received a lot of attention in wastewater treatment as one of the treatment technologies. The purpose of this paper is to provide readers with valuable information about EO definitions, mechanisms, operational conditions, and statistical analysis based on recent articles. According to the review, EO is more effective in removing organic contaminants than other methods. This depends on whether additional chemicals are used and the type of anode materials. The material of the anode, contact time, pH, and current density are the most crucial parameters of EO technology. The paper demonstrates that selecting the appropriate anode electrode was a significant challenge in treating wastewater through electro-oxidation. According to the cited papers, EO has been used by more than 85% of them alone, while the remaining 10% have utilized it in combination with other conventional and development methods for wastewater treatment. Compared to other materials, titanium was the most commonly used material for anode manufacturing in EO technology. Electrochemical oxidation technology is a reliable method to eliminate a diverse range of pollutants from various wastewater types

Laura M. González-Méndez, Silvia Y. Martínez-Amador, Leopoldo J. Ríos-González et al.

Processes • 2025

Anthropogenic activities, such as agricultural, industrial, and domestic, generate wastewater, leading to environmental concerns. Wastewater constituents (organic matter, pathogens, pharmaceuticals, heavy metals, and nutrients) have a negative impact if not treated, harming ecosystems and human health. Phytoremediator plants are a good option for domestic wastewater treatment since they help remove pollutants through their physiological activities, which are highly related to anatomical adaptations due to their growth in humid habitats. Macrophytes are a useful tool when coupled with a bioelectrochemical constructed wetland and MFC (CW-MFC), which can enhance the removal efficiency of organic matter present in wastewater and promote higher bioelectricity due to the root activity of plants. This review aims to compare different aquatic macrophyte types in wastewater treatment efficiency and provide useful information for plant selection.

G. Lettinga

Water Science and Technology • 1996

The actual and potential benefits of anaerobic wastewater treatment when implemented at the core of a sustainable and non-vulnerable environmental protection programme are described. The paper focuses on the anaerobic sludge bed (and in particular the expanded granular sludge bed (EGSB)) reactor concept. Start-up of these systems is shown to be rapid, within a few days with granular seed sludges, and they may be applied across a wide range of conditions and strengths of wastewater. EGSB systems are particularly suited to low temperatures (10°C) and very low strengths (<<1000mg/1) and for the treatment of recalcitrant or toxic substrates.