Electrochemical Advanced Oxidation of Lamotrigine at Ti/DSA (Ta2O5-Ir2O5) and Stainless Steel Anodes

Treatment of dyeing wastewater by combined sulfate radical based electrochemical advanced oxidation and electrocoagulation processes

Present study is a novel attempt to experimentally verify that electrochemical treatment of organic pollutants on stainless steel (SS) anode is a combination of electro‐oxidation (EO) and electro‐coagulation (EC) with quantitative estimation of individual contributions of the two mechanisms. Target organic pollutants, metformin HCl (MET‐HCl) and lamotrigine (LAM), were electrochemically treated with SS anode for this purpose. Experiments were designed using central composite rotatable design (CCRD) to assess the effect of current density (CD) and supporting electrolyte concentration (SEC) as independent process parameters. Under all conditions, the process was experimentally verified to be a combination of EO and EC. For MET‐HCl, true mineralization (TM) as a result of EO contribution varied between 50.13% and 66.64%. EO contribution and resulting TM for LAM ranged from 37.5% to 61.83%. EC contributed 30.6%–31.84% towards MET‐HCl remediation causing the TOC to be transferred from the liquid to the sludge produced (SP). EC contribution was 23.68%–35.89% for LAM remediation. Thus, apparent mineralization (AM), the sum of EO and EC contributions, ranged from 80.63% to 97.79% for MET‐HCl and 61.18% to 96.82% for LAM.Process parameters were statistically optimized using response surface methodology (RSM) to simultaneously maximize TM and AM with minimal energy consumption and maximal current efficiency. The optimized conditions were 0.83 mA/cm2 CD and 86.66 ppm SEC for MET‐HCl. The corresponding values were 1.31 mA/cm2 CD and 79.51 ppm SEC for LAM.

Mixed industrial wastewater treatment by combined electrochemical advanced oxidation and biological processes

As pollution becomes one of the biggest environmental challenges of the twenty-first century, pollution of water threatens the very existence of humanity, making immediate action a priority. The most persistent and hazardous pollutants come from industrial and agricultural activities; therefore, effective treatment of this wastewater prior to discharge into the natural environment is the solution. Advanced oxidation processes (AOPs) have caused increased interest due to their ability to degrade hazardous substances in contrast to other methods, which mainly only transfer pollution from wastewater to sludge, a membrane filter, or an adsorbent. Among a great variety of different AOPs, a group of electrochemical advanced oxidation processes (EAOPs), including electro-Fenton, is emerging as an environmental-friendly and effective treatment process for the destruction of persistent hazardous contaminants. The only concern that slows down a large-scale implementation is energy consumption and related investment and operational costs. A combination of EAOPs with biological treatment is an interesting solution. In such a synergetic way, removal efficiency is maximized, while minimizing operational costs. The goal of this review is to present cutting-edge research for treatment of three common and problematic pollutants and effluents: dyes and textile wastewater, olive processing wastewater, and pharmaceuticals and hospital wastewater. Each of these types is regarded in terms of recent scientific research on individual electrochemical, individual biological and a combined synergetic treatment.

This study was performed to evaluate the temperature, pH change, and electrolysis products at the anode during transcatheter electrocoagulation (TCEC). Stainless steel and platinum anodes insulated by standard angiographic catheters were placed in renal dialysis tubing. The tubing, filled with either saline solution or plasma, was placed in a water bath (25 degrees C) containing a cathode. Temperature was recorded at the tip of the anode, placed in saline solution, using 15 ma for 20 minutes (n = 5 for each wire and current). pH was measured during applications of 15, 30, and 60 ma for 20 minutes (n = 6 for each current, anode, and solution). The solutions were analyzed for products of electrolysis. The temperature remained constant. The pH declined to 1.5 +/- .3 (mean +/- SEM) with the platinum electrode and to 2.5 +/- .5 with the stainless steel anode. Metallic elements and oxygen were the electrolysis products recovered from the stainless steel experiments. Chlorine gas was the major product recovered from the platinum studies. These results confirm that during TCEC there is no thermal injury. The pH change at the anode is probably a major mechanism in TCEC. Different types of reactions take place at platinum and stainless steel anodes, which may account for differences between TCEC with these two electrodes.

Increasing environmental pollution and shortage of critical resources call for technologies capable of achieving total resource recovery from waste materials. In this study, high leaching rates of 99.16% for lithium and 97.37% for iron were obtained from spent lithium iron phosphate (LFP) batteries through electrochemical (EC) advanced oxidation processes (EAOPs), and associated leaching mechanism was subsequently investigated. Moreover, residual C, Fe, and P elements in leach residue were directly converted into a P, N-doped asymmetric single-atom Fe catalyst (Fe-CN3P), enabled by well-dispersion of Fe elements and removal of surface passivation layers during leaching. When activated with peroxymonosulfate (PMS), Fe-CN3P catalyst exhibited a pseudo-first-order kinetic rate of 10.768 min-1 for bisphenol A (BPA) degradation, which is approximately 2-10 times higher than those of conventional single-atom catalysts. Based upon experimental and theoretical investigation, the presence of P in the local coordination environment was found to substantially enhance catalytic activity of Fe sites. P incorporation alters the adsorption mode of HSO5 - on Fe active centres and increases Bader charges in the FeIV═O reactive intermediate, thereby improving the capability of Fe to withdraw electrons from the BPA molecules. This study offers new perspectives for synergistically advancing "comprehensive resources recovery" and "waste to treat waste."

Increasing environmental pollution and shortage of critical resources call for technologies capable of achieving total resource recovery from waste materials. In this study, high leaching rates of 99.16% for lithium and 97.37% for iron were obtained from spent lithium iron phosphate (LFP) batteries through electrochemical (EC) advanced oxidation processes (EAOPs), and associated leaching mechanism was subsequently investigated. Moreover, residual C, Fe, and P elements in leach residue were directly converted into a P, N‐doped asymmetric single‐atom Fe catalyst (Fe‐CN 3 P), enabled by well‐dispersion of Fe elements and removal of surface passivation layers during leaching. When activated with peroxymonosulfate (PMS), Fe‐CN 3 P catalyst exhibited a pseudo‐first‐order kinetic rate of 10.768 min −1 for bisphenol A (BPA) degradation, which is approximately 2–10 times higher than those of conventional single‐atom catalysts. Based upon experimental and theoretical investigation, the presence of P in the local coordination environment was found to substantially enhance catalytic activity of Fe sites. P incorporation alters the adsorption mode of HSO 5 − on Fe active centres and increases Bader charges in the Fe IV ═O reactive intermediate, thereby improving the capability of Fe to withdraw electrons from the BPA molecules. This study offers new perspectives for synergistically advancing “comprehensive resources recovery” and “waste to treat waste.”

Electrochemical advanced oxidation for treating ultrafiltration effluent of a landfill leachate system: Impacts of organics and inorganics and economic evaluation

Performance of Nb/BDD material for the electrochemical advanced oxidation of prednisone in different water matrix

Influence of the anode material on the degradation of naproxen by Fenton-based electrochemical processes

Elimination of radiocontrast agent Diatrizoic acid from water by electrochemical advanced oxidation: Kinetics study, mechanism and mineralization pathway

Incineration of acidic aqueous solutions of dopamine by electrochemical advanced oxidation processes with Pt and BDD anodes

Bench scale electrocoagulation studies of bio oil-in-water and synthetic oil-in-water emulsions

Degradation of diuron in water by electrochemical advanced oxidation in a microreactor: effects of anion contamination on degradation and toxicity

Dairy wastewater (DW) contains a high concentration of organic and inorganic pollutants. In recent years, extensive research has been conducted to develop more efficient techniques for the treatment of DW. Electrochemical advanced oxidation processes (EAOPs) have gained significant attention among the various treatment approaches. EAOPs rely on electrochemical generation of hydroxyl radicals (•OH) which are considered highly potent oxidizing compounds for the degradation of pollutants in DW. In this paper, we provide an overview of the treatment of DW using various EAOPs, including anodic oxidation (AO), electro-Fenton (EF), photo electro-Fenton (PEF), and solar photo electro-Fenton (SPEF) processes, both individually and in combination with other techniques. Additionally, we discuss the reactor design and operating parameters employed in EAOPs. The variation in degradation efficiency is due to different oxidizing agents produced in specific approaches and their pollutant degradation abilities. In AO process, •OH radicals generated on electrode surfaces are influenced by electrode material and current density, while EF procedures use Fe2+ to create oxidizing agents both on electrodes and in the DW solution, with degradation mechanisms being affected by Fe2+, pH, and current density; additionally, PEF and SPEF approaches enhance oxidizing component production and pollutant degradation using ultraviolet (UV) light. Integration of EAOPs with other biological processes can enhance the pollutant removal efficiency of the treatment system. There is a scope of further research to exhibit the effectiveness of EAOPs for DW treatment in large scale implementation.