Boron Removal Research Articles

Morphological justification of the complex treatment program of gastroduodenal disorders on the background of chronic pancreatitis

In this paper an innovative precipitation process that uses the leachate from the acid washing of combustion bottom ash (bottom ash leachate, BAL) together with Ca(OH)2 was developed for the removal of boron from water. Several batch experiments were conducted to identify the most suitable operating conditions by treating real “produced water” generated during oil extraction activities. The developed process consists of an initial acidification, followed by the dosage of BAL and, then, by the addition of Ca(OH)2. The best removal performances were obtained by setting the initial pH at 1 and reaching a final value of 11 through the addition of Ca(OH)2. Boron abatement rapidly grew in response to the increase of bottom ash leachate dosage up to a dose of 20 mL/L, beyond which the removal yield showed an asymptotic trend. The process proved to be very fast reaching the steady state within 10 min and the removal trends were accurately described by a pseudo-second order kinetic law. The temperature had a positive effect on the process performance when using low BAL dosages for values up to 40 °C. Beyond this temperature there was a deterioration in the boron removal regardless of the dose of bottom ash leachate. An abatement efficiency close to 90 % was reached at T = 20 °C by dosing in sequential steps five aliquots of an overall BAL dosage of 20 mL/L. The characterization of precipitate proved the coexistence of multiple compounds in both crystalline and amorphous form. The treated water had very low concentrations of metallic ions.

Optimal design and operation of reverse osmosis seawater desalination system for boron removal with economic, energy, and environmental concerns

This paper introduces a superstructure-based simultaneous optimum design and operation of seawater reverse osmosis (RO) system with boron removal under time-variant constraints. Three operational strategies are utilized to improve operability of the system under boron restrictions, including changing the activated number of pressure vessels, permeates split ratio, and pH values. Moreover, exergo-environmental and exergo-econoenvironmental analysis models are integrated. The economic efficiency, energy utilization, and environmental impact could be optimized in both design and operation phases. The effect of water tank area, membrane type, and boron concentration on water production are investigated with constant feed conditions. Choosing proper water tank volume and type of membrane could not only reduce cost but also better operation conditions, such as improving the efficiency of pumps and reducing feed pH of RO pass 2. When both the eco-costs/value ratio and emergy rate of product are added as a penalty, the annual operation cost (a reduction of 5.50 %), emergy rate (a reduction of 7.02 %) and eco-costs/value ratio (a reduction of 7.48 %) of the product could be reduced with only a small amount of water cost increment (about 2.66 %). Improving the efficiency of pumps would be an effective method to improve overall performance of the RO plant.

Hybrid adsorptive nanofiltration hollow fiber membranes with charge-patterned UiO-66 incorporated thin-film nanocomposite selective layer for enhanced boron removal

Herein, hybrid adsorptive nanofiltration (NF) hollow fiber (HF) membranes with the charge-patterned structure were fabricated and characterized for enhanced boron removal application. Mg–Al layer double hydroxide (LDH) and bentonite nanoparticles (NPs) were used as adsorbents in the support layer, while pristine and novel amine modified UiO-66 metal-organic frameworks (MOFs) were used to synthesize thin-film nanocomposite polyamide (PA) selective layer. UiO-66 was modified using triethylamine (TEA) and polyethylene imine (PEI) and the modification was approved through FTIR, DLS, and FESEM analyses. Prior to the performance evaluation of the fabricated membranes, the feasibility of boron removal by PA, and pristine and modified UiO-66 was investigated using molecular dynamics (MD) simulation and the diffusion coefficients were estimated. The structure of the fabricated thin film composite (TFC) and thin film nanocomposite (TFN) membranes were characterized by AFM, zeta potential and FESEM analyses showing agglomeration of the MOFs at 0.1 wt%. Membrane performance in boron removal was evaluated through brackish water condition at 4 bar in neutral and alkaline pH. The results showed that the contribution of the adsorptive support is 8 and 4% for the supports containing LDH and bentonite, respectively. Boron removal of the UiO-66 TFN membrane was achieved up to 58%, while the charge-patterned UiO-66/PEI TFN membrane was able to remove boron up to 87 and 91% at neutral and alkaline pH conditions.

Fabrication of high boron removal reverse osmosis membrane with broad industrial application prospect by introducing sulfonate groups through a polyvinyl alcohol coating

The effective removal of boron from water is highly desirable for many chemical processes. Reverse osmosis (RO) membrane technology has been considered to be a competitive technology for boron removal. However, in addition to seawater, RO membrane technology is rarely used in the treatment of other industrial wastewaters containing boron. In this work, a high boron removal RO membrane with broad industrial application prospect was developed. Specifically, sulfonate groups were grafted onto the surface of the RO membrane through the acetal reaction of polyvinyl alcohol (PVA) with benzaldehyde disulfonic acid disodium salt (BADSA Na). In this process, PVA was coated on the membrane surface in advance. The possibility that large complexes can form due to the reaction between PVA and boric acid and the characteristic of the sulfonate group which can decrease the hydrogen bonding sites work together to reduce the rate of boron diffusion, and then a high boron removal rate is achieved. Under seawater conditions, the boron removal rate of the membrane was improved obviously from 85.71% to 91.63%, while a high flux of 44.41 L m−2 h−1 and a high salt rejection of 99.63% was maintained. In addition, the membranes developed were able to maintain excellent boron removal performance in three other industrial water scenarios (geothermal water, nuclear power plant wastewater and oilfield fracturing flowback fluid). Furthermore, the overall performance of the membrane is better than that of other commercially available membranes and existing processes, showing that the membrane developed has a bright promise for various industrial applications.

Analysis of Boron Removal By Capacitive Deionization

Climate change and water overextraction are some of the reasons for a growing global water stress, with seawater desalination being the leading solution worldwide. The state-of-the-art technology for seawater desalination is reverse osmosis (RO), utilizing mechanical pressure to push seawater through membranes, leaving the dissolved species in the brine. However, boron, which is considered toxic in high concentrations, is poorly removed by RO. This is because under normal conditions boron is present as boric acid, a small neutrally-charged compound. The most common technique to overcome this problem includes multiple RO stages combined with chemical dosage of the effluent, ensuring boron is present as borate, a charged species, present in high pH conditions.Capacitive deionization (CDI) is an emerging membraneless technique for water treatment and desalination, based on electrosorption of salt ions into microporous electrodes. Large internally-generated pH gradients develop during CDI operation, and thus CDI can potentially remove boron without chemically adjusting the feed pH. Here, we present a novel theoretical framework predicting the adsorption of boron in micropores, while considering pH-dependent chemical surface groups in the micropores, ion transport in the macropores, and local electrolyte pH. Moreover, we account for association and dissociation reactions of boron-consisting compounds in the electrolyte[1].We analyzed the effects electrodes order have on pH dynamics, where panels a. and b. in the attached figure present spatiotemporal plots of the pH for the case where cathode is placed upstream (panel a., cat-an) and the anode placed upstream (panel b., an-cat). This analysis shows that higher pH in the anode are expected for the an-cat configuration, counter to common-wisdom in the field. Panel c. follows this trend, by presenting the removed boron as a function of scaled flow velocity for both configurations. The results show, both experimentally and theoretically, that an-cat configuration should be preferred. Similarly, we found that an optimum charging voltage exists, even without accounting for parasitic reactions. Moreover, we found that also the discharging voltage significantly affects boron removal. Overall, CDI is a promising technology for boron removal, but a deep theoretical understanding of the problem is crucial towards future optimization.

Use of banana peel for the removal of boron from aqueous solutions in the batch adsorption system

Use of banana peel for the removal of boron from aqueous solutions in the batch adsorption system

Effect of silicon on the mathematical model prediction and adsorption mechanism of boron removal by a fixed-bed column

To promote the practical application of a novel resin (tiron-modified resin) in the removal of toxic element boron from actual water, the dynamic adsorption of boron was investigated in the presence of silicon by a fixed-bed column. The breakthrough time, exhaustion time and adsorption capacity of the column bed decreased in the presence of silicon due to competitive adsorption. The boron adsorption capacity decreased from 5.01 mg/g to 2.91 mg/g in the mixed solution compared with the single solution containing the same initial concentration. However, the total adsorption capacity (the sum of boron and silicon) was close to that of single boron. The Thomas and Yoon-Nelson models can appropriately predict the whole breakthrough curves (BTCs) of boron and the sum of both elements during the column bed adsorption process despite the coexistence of silicon. This result will have great reference value in related fields. The mixed adsorption mechanism of boron and silicon varied from single adsorption. For boron, besides the formation of triangular and tetrahedral complexes, the B-O-Si chemical bonds were also formed. However, the silicon was mainly adsorbed via monomers, with the addition of one-dimensional linear polymer and two-dimensional sheet polymers. The presence of silicon reduced the life factor of the column bed's capability to avoid breakthrough time from 6.8 to 5.5 cycles at t = 0, but prolonged the completely exhausting time from 7.8 to 11.7 cycles. T-resin manifests itself in preferential and continuous adsorption of boron, showing enormous potentialities for controlling boron pollution in actual waters.

Removal of Borate Ions from Wastewater Using an Adsorbent Prepared from Waste Concrete (PAdeCS).

The removal of boron from model wastewater using PAdeCS, a material derived from waste concrete, was studied. Three different types of boron removal methods were examined: adsorption with untreated PAdeCS, adsorption with heat-treated ettringite-enriched PAdeCS, and coagulation–sedimentation method by mixing untreated PAdeCS as a calcium source and aluminum sulfate as an aluminum and sulfate ion source for the formation of ettringite. The highest boron removal performance was observed for the coagulation–sedimentation method, where the boron concentration in the model wastewater decreased rapidly from 100 mg/L to the level below the Japanese effluent standard at 10 mg/L when the weight ratio of PAdeCS addition into water is 4.0% with aluminum sulfate, of which the added amount corresponds to the stoichiometric condition for the formation of ettringite (Ca:Al:SO42– = 6:2:3). The heat-treated ettringite-enriched PAdeCS also showed higher boron removal performances compared with untreated PAdeCS. The dependency of the boron removal capacity on the aqueous boron concentration can be expressed by the Langmuir equation for all the cases. The maximum capacity (qm) values were 1.83, 3.39, and 3.02 mg/g-solid for adsorption with untreated PAdeCS, adsorption with heat-treated ettringite-enriched PAdeCS, and coagulation–sedimentation, respectively. These capacities were higher or comparable with the ones reported in the literature.

Boron Removal from Synthetic Hydraulic Fracturing Wastewaters by Hybrid Nanofiltration/Complexation Process

<p>The primary purpose of this study is to investigate boron removal from synthetic hydraulic fracturing wastewater by membrane processes. The effects of pressure, pH, feed concentration, and polyol concentration on boron removal were determined using a cross-flow, flat-sheet membrane test unit. The nanofiltration membrane was tested within the scope of the experiments. Accordingly, it was determined that the boron removal increased with pressure, pH, and boron concentration. Under the influence of all these variables, the complexing polyol was used in the membrane experiments to remove the boron at a higher level. Xylitol, one of the polyols that forms the most efficient complex with boric acid, was added to the synthetic hydraulic fracturing wastewater at specific molar ratios. In NF membrane tests with polyol addition, >80% boron removal was recorded under specific operating conditions. High-quality permeate water obtained after membrane treatment can be reused as a hydraulic fracturing fluid. It has been proven that the proposed treatment setup can be an effective alternative for boron removal from hydraulic fracturing wastewater.</p>

Fabrication of fluorinated polyamide seawater reverse osmosis membrane with enhanced boron removal

Developing a reverse osmosis membrane with desirable water/salt selectivity and boron removal has been recognized as crucial for high-efficient seawater desalination. Herein, fluorinated seawater reverse osmosis (SWRO) membranes were fabricated via fluorine-containing monomers-mediated interfacial polymerization or surface modification by grafting fluorine-containing monomers atop nascent polyamide (PA) layer via a second interfacial reaction. The fluorinated molecules, 5-(trifluoromethyl)-1.3-phenylenediamine (TFPD), 3,5-bis(trifluoromethyl) benzoyl chloride (TFBC) or 2,2,2-trifluoroethylamine (TFEA), were confirmedly integrated into the PA matrix presumably via strong chemical covalent bonds, which manipulated the physicochemical properties of the PA layer, including surface hydrophilicity, pore size distribution, cross-linking degree and interactions between membrane and solutes, thereby producing a high-selectivity thin-film composite (TFC) membrane. The optimized membranes, i.e., TFC-TFPD, TFC-TFBC and TFC-TFEA, presented significantly excellent separation performance than the control and commercial membrane, both in water/salt selectivity and boron removal capability, accompanied by a comparable water permeance. Among the three proposed incorporation method of fluorinated monomers, direct grafting of TFEA upon the nascent PA layer demonstrates the best efficiency in introducing fluorine elements in the TFC PA membranes, compared to the addition of TFPD and TFBC into aqueous and organic phases during IP process, respectively. The fluorine-incorporated strategy employed in this present work offered a new design of the PA layer containing fluorinated molecules to obtain the desired permselectivity of TFC SWRO membranes towards efficient removal of salt and boron acid in seawater desalination.

Biosorption of Boron from Industrial Wastewater by Green Algae Spirogyra sp.

Introduction: Increasing the concentration of Boron in drinking water, wastewater, and irrigation have negative effects on the human environment. This pollution can be partially removed by the application of phytoremediation technologies using algae or aquatic plants. The aim of the current study was to determine the biosorption capacity of the algae Spirogyra sp. for Boron from industrial wastewater and examine the best elimination conditions using different parameters.
 Materials and Methods: In this study, 100 g of fresh algal biomass was collected from the industrial wastewater of a copper mine located in Kerman, Iran.
 At first, algae was selected among various algal species concerning abundance and resistance ability to high concentrations of Boron. Then, removal of Boron by the algal was examined in terms of algae biomass levels (2 and 4 gr), incubation time intervals (2, 12. 24. 48, and 72 hours), and different concentrations of Boron (5, 10, 15, 25, and 100 ppm) on the were examined. The experiment was factorial with a completely randomized design framework and three replications.
 Results: The results presented that the elimination of Boron from industrial wastewater was performed by biomass of algae Spirogyra sp. The maximum Boron absorption was achieved at concentrations of 5 ppm and an incubation time of 12 hours. The absorption of Boron was higher in 4 gr than in 2 gr of algae biomass treatment.
 Conclusion: It can be concluded that algae Spirogyra sp. has a strong potential for boron removal in industrial wastewater containing boron ions.

Advances in Technologies for Boron Removal from Water: A Comprehensive Review.

Boron overabundance in aquatic environment raises severe concerns about the environment and human health because it is toxic to various crops and induces many human and animal diseases with long-term consequences. In response to the boron pollution of water resources and the difficulty of eliminating boron from water for production and living purposes, this article summarizes the progress in research on boron removal technology, addressing the following aspects: (1) the reasons for the difficulty of removing boron from water (boron chemistry); (2) ecological/biological toxicity and established regulations; (3) analysis of different existing processes (membrane processes, resin, adsorption, chemical precipitation, (electric) coagulation, extraction, and combined methods) in terms of their mechanisms, effectiveness, and limitations; (4) prospects for future studies and possible improvements in applicability and recyclability. The focus of this paper is thus to provide a comprehensive summary of reported deboronation processes to date, which will definitely identify directions for the development of boron removal technology in the future.

Adsorptive Membrane for Boron Removal: Challenges and Future Prospects.

The complexity of removing boron compounds from aqueous systems has received serious attention among researchers and inventors in the water treating industry. This is due to the higher level of boron in the aquatic ecosystem, which is caused by the geochemical background and anthropogenic factors. The gradual increase in the distribution of boron for years can become extremely toxic to humans, terrestrial organisms and aquatic organisms. Numerous methods of removing boron that have been executed so far can be classified under batch adsorption, membrane-based processes and hybrid techniques. Conventional water treatments such as coagulation, sedimentation and filtration do not significantly remove boron, and special methods would have to be installed in order to remove boron from water resources. The blockage of membrane pores by pollutants in the available membrane technologies not only decreases their performance but can make the membranes prone to fouling. Therefore, the surface-modifying flexibility in adsorptive membranes can serve as an advantage to remove boron from water resources efficiently. These membranes are attractive because of the dual advantage of adsorption/filtration mechanisms. Hence, this review is devoted to discussing the capabilities of an adsorptive membrane in removing boron. This study will mainly highlight the issues of commercially available adsorptive membranes and the drawbacks of adsorbents incorporated in single-layered adsorptive membranes. The idea of layering adsorbents to form a highly adsorptive dual-layered membrane for boron removal will be proposed. The future prospects of boron removal in terms of the progress and utilization of adsorptive membranes along with recommendations for improving the techniques will also be discussed further.

Phytoremediation of Boron From Wastewater in Vertical Flow Constructed Wetlands

The aim of this work was to evaluate the possibility of boron removal from synthetic wastewater using a vertical constructed flow (VFCW) planted with Vetiveria zizanioides. Two boron concentrations were used (15 ± 1 and 30 ± 1 mg L−1) and a hydraulic load (HL) of 191 ± 10 L m−2d−1. The wastewater samples were taken and the flow rate in the inlet and outlet of the VFCW were measured. The levels of dissolved oxygen, electrical conductivity, pH and boron were determined in the wastewater. The concentrations of the essential elements and nutrients, namely total Kjeldhal nitrogen, phosphorus, calcium, magnesium, sodium and potassium in above growth biomass composition were measured. The results showed that: boron removal efficiencies depended on the boron concentration, so 60 ± 3% was obtained for the 15 mg L−1 concentration and 26 ± 2% for 30 mg L−1; calcium, magnesium, potassium and sodium concentrations in the vegetal biomass decreased to the boron concentration of 30 mg L−1, and boron may have interfered with Vetiveria zizanioides growth.
 Keywords: biomass composition, boron removal, light expanded clay aggregates, Vetiveria zizanioides, vertical flow constructed wetland

Boron removal and recovery from water and wastewater

Boron removal and recovery from water and wastewater

Partition model for trace elements between liquid metal and silicate melts involving the interfacial transition structure: An exploratory two-phase first-principles molecular dynamics study

Separation of trace elements has become a major obstacle for preparation of high-purity metal materials. Effective design of the separation medium depends on accurate partitioning prediction of the trace elements in the two phases. However, development of a separation prediction model is difficult because of the limitations of recognition of the interfacial transition structures of the trace elements. Here, a partition model for trace elements between metal and silicate melts involving an interfacial transition structure was developed by exploratory two-phase first-principles molecular dynamics simulation. The results showed that the distribution strongly depends on the local coordination structure in the cluster (LCSC) of the impurity element, which is the key for investigating the interfacial transition structure. A computational strategy for the trace-element distribution ratio is proposed to quantify the contribution of the trace element at the interface. The LCSC partition model was demonstrated for trace element boron removal from silicon for molten silicon and silicate melts. The LCSC model gave a better predicted value of the experimental value than the traditional activity model. The new model assists in explaining the transformation mechanism of B atoms at the silicate–silicon interface at the atomic scale. The LCSC partition model allows prediction of the trace element partitioning behavior solely from first-principles calculations.

Boron removal from synthetic brines and oilfield produced waters using aluminum electrocoagulation

High boron (B) levels in oil and gas produced waters prevent its beneficial reuse as irrigation water without proper treatment. Aluminum (Al) electrocoagulation (EC) is a promising technology for B removal, but further research and development is needed to optimize EC for use in removing B from produced waters. To this end, B removal by adsorption onto insoluble aluminum hydroxide solids, generated by EC in simulated brines (up to 50,000 mg/L NaCl) and real oilfield produced waters, was studied. B removal during EC was greater than when aluminum hydroxide solids formed by EC were subsequently exposed to B containing solutions. Working parameters affecting B removal during the EC process, including current, total dissolved solid (TDS), temperature, pH, scale-forming cations and organic matter, were investigated to explore ways to achieve higher B removal. Boron removal increased with increased current loading and time, and with the concomitant increased Al solids concentration. However, too high a current loading limited B removal because of a change in the structure of the aluminum hydroxide solids. Higher TDS decreased B removal slightly, but lower TDS concentrations limited the use of higher current loadings. Temperature increased during EC treatment, particularly at higher current loadings, and this inhibited B removal due to an accelerated aggregation of amorphous Al solids into larger, denser, and presumably more crystalline particles. The best B removal occurred at pH 8, corresponding to a slightly positive zeta potential for aluminum hydroxide and a small but significant fraction of negatively charged B species. Scale-forming cations such as Ba2+ and Sr2+ had no obvious effect on the EC process. The presence of high concentrations of Mg2+ and Ca2+ resulted in low bulk pH values during the EC process and greater formation of solid products, but B removal did not decrease during a pH-controlled (pH = 8) EC process with these divalent cations present. Two produced water samples collected from oilfields in Kansas, US were treated using EC for 1 h, resulting in up to ~70 % B removal from solution with a current loading of 6.67 A/L, and up to 78 % with 13.33 A/L.

Infiltration of 3D-macrocycles to integrally skinned asymmetric P84 co-polyimide membranes for boron removal

We have molecularly designed negatively charged nanofiltration (NF) membranes by chemical modification of P84 flat membranes with hyperbranched polyethylenimine (HPEI) polymers and then infiltration of sulfocalix[4]arene (SCA4) to enhance their chemical stability and molecular sieving capability. The high molecular weight HPEI polymers developed a strong cross-linked network of P84 polymer chains with extraordinary chemical stability in solvents like N-methyl-2-pyrrolidone (NMP). In addition, the amine groups of HPEI ionically bonded with the electron-accepting sulfonic acid groups of SCA4, resulting in the cross-linked membranes with a proper pore dimension and enhanced size sieving capability. The NF membrane infiltrated with SCA4 in a 0.03 wt% SCA4 solution consisting of 50/50 (wt%) water and methanol for 8 h has boron rejections of 55.37 %, 67.23 %, 87.45 %, 89.95 %, and 98.24 % at pH = 4, 7, 8, 9 and 10, respectively. These performances are comparable with or superior to literature results for membranes made from thin-film interfacial polymerization. The unique SCA4 closed-loop structure not only enhances molecular sieving capability but also achieves negatively charged NF membranes that maximize the potential for removal of toxic ions. This study may provide useful insights to design NF membranes with the aid of supramolecular macrocycles for water reuse and removal of toxic ions.

In situ reactive coating of porous filtration membranes with functional polymer layers to integrate boron adsorber property

The state-of-the-art reverse osmosis membranes for seawater desalination have limited competence to efficiently remove boron. One promising approach for boron removal is to integrate membrane-based separation with selective adsorption of boron in pre- or posttreatment of seawater desalination; the porous support layer of established filtration membranes, constituting the largest part of total membrane volume shall be utilized for this function. Therefore, this study focuses on performing in situ modification of commercial polyethersulfone (PES) microfiltration membranes toward reactive coating the pore surface with a boron affinity polymer-based hydrogel. Modification is carried out in two steps: 1) adsorption of an amphiphilic copolymer which contains tertiary amine groups as co-initiator for surface-selective free radical generation; 2) grafting of a hydrogel layer by using a monomer solution comprising polyol-containing monomer as boron ligand, a cross-linker monomer, and the redox initiator ammonium persulfate (APS). The entire modification process is performed under flow-through conditions. Membranes with different pore sizes were modified; modification parameters, such as molar mass of macromolecular co-initiator as well as composition of reactive monomer solution, were systematically varied. It was found that using an “integrated” initiation system with low molecular weight co-initiator N,N,N′,N′-tetraethyl ethylenediamine (TEMED) added to the reactive solution, yielded significantly higher degree of grafting and therefore superior adsorber properties. Boron binding capacity of modified membranes was evaluated in terms of boron adsorption isotherms, adsorption kinetics, break-through behavior under filtration conditions and regeneration of the adsorber. The trade-off between permeance and boron binding capacity of modified membrane was studied in order to identify promising materials with competitive overall separation performance, i.e. high permeance at a specific filter cut-off in combination with high boron binding capacity.

Boron Removal from Reverse Osmosis Permeate Using an Electrosorption Process: Feasibility, Kinetics, and Mechanism.

Boron is present in the form of boric acid (B(OH)3 or H3BO3) in seawater, geothermal waters, and some industrial wastewaters but is toxic at elevated concentrations to both plants and humans. Effective removal of boron from solutions at circumneutral pH by existing technologies such as reverse osmosis is constrained by high energy consumption and low removal efficiency. In this work, we present an asymmetric, membrane-containing flow-by electrosorption system for boron removal. Upon charging, the catholyte pH rapidly increases to above ∼10.7 as a result of water electrolysis and other Faradaic reactions with resultant deprotonation of boric acid to form B(OH)4- and subsequent removal from solution by electrosorption to the anode. Results also show that the asymmetric flow-by electrosorption system is capable of treating feed streams with high concentrations of boron and RO permeate containing multiple competing ionic species. On the basis of the experimental results obtained, a mathematical model has been developed that adequately describes the kinetics and mechanism of boron removal by the asymmetric electrosorption system. Overall, this study not only provides new insights into boron removal mechanisms by electrosorption but also opens up a new pathway to eliminate amphoteric pollutants from contaminated source waters.