Adsorption and photodegradation of microcystin-LR onto sediments collected from reservoirs and rivers in Taiwan: a laboratory study to investigate the fate, transfer, and degradation of microcystin-LR

Background, aim, and scope

This study demonstrated the adsorption capacity of microcystin-LR (MC-LR) onto sediment samples collected from different reservoirs (Emerald and Jade reservoirs) and rivers (Dongshan, Erhjen, and Wukai rivers) in Taiwan to investigate the fate, transport behavior, and photodegradation of MC-LR.

Main features

Langmuir adsorption and photodegradation studies were carried out in the laboratory and tested the capability of sediments for MC-LR adsorption. These data suggested that sediments play a crucial role in microcystins degradation in aquatic systems.

Results and discussion

The results of batch experiments revealed that the adsorption of MC-LR varied significantly with texture, pH, and organic matter content of sediments. Silty and clay textures of the samples were associated with larger content of organic matter, and they displayed the enhanced MC-LR adsorption. Low pH sediment showed increased adsorption of MC-LR. The effective photodegradation of MC-LR (1.6 ??g/mL) was achieved within 60 min under 254 nm light irradiation.

Conclusion

A comparative study of adsorption capacity of all sediment samples was carried out and discussed with respect to different aspects. Among all, sediments collected from Jade reservoir showed enhanced MC-LR adsorption (11.86 ??g/g) due to favored textural properties (BET surface area = 20.24 m2/g and pore volume = 80.70 nm).

Perspectives

These data provide important information that may be applied to management strategies for improvement of water quality in reservoirs and rivers and other water bodies in Taiwan.     

磁性介孔锰铁复合氧化物对Cr(Ⅵ)的吸附性能研究

以复合金属草酸盐为前驱体制备了纳米晶构筑的介孔锰铁氧化物材料,采用透射电镜、X射线衍射仪和固体比表面测定仪等对产物进行了表征.并研究了其对水体Cr(Ⅵ)的吸附性能,考察了pH及离子强度对吸附容量的影响、吸附动力学、吸附等温线以及碱液对Cr(Ⅵ)的洗脱率。结果表明,获得的锰铁氧化物为纳米晶构筑的介孔材料,比表面达277.4 m2/g,对Cr(Ⅵ)在酸性条件下有较强的吸附性能。在初始Cr(Ⅵ)质量浓度为100 mg/L,pH值在2时,10 min内能使溶液中的Cr(Ⅵ)去除率达96.8%,最大Cr(Ⅵ)吸附容量Qm为40 mg/g。     

Characterization and lead(II), cadmium(II), nickel(II) biosorption of dried marine brown macro algae Cystoseira barbata

Purpose

The objectives of this research are to identify the functional groups and determine corresponding pK _a values of the acidic sites on dried brown algae Cystoseira barbata using FTIR and potentiometric titrations, and to investigate the biosorption ability of biomass towards divalent nickel, cadmium, and lead ions. Adsorption was studied as a function of solution pH and contact time, and experimental data were evaluated by the Langmuir isotherm model.

Methods

CaCl₂ pretreatment was applied to the sorbent for enhancing the metal uptake capacity. The effect of solution pH on biosorption equilibrium was investigated in the pH range of 1.5?C5.0. Individual as well as competitive adsorption capacity of the sorbent were studied for metal cations and mixtures.

Results

The retention of the tested metal ions was mostly influenced from pH in the range of 1.5?C2.5, then stayed almost constant up to 5.0, while Ni(II) uptake showed the highest variation with pH. Potentiometric titrations were performed to find the number of strong and weak acidic groups and their acidity constants. The density of strong and weak acidic functional groups in the biomass were found to be 0.9 and 2.26?mmol/g, respectively. The FTIR spectra of the sorbent samples indicated various functionalities on the biomass surface including carboxyl, hydroxyl, and amino and sulphonate groups which are responsible for the binding of metal ions.

Conclusions

The capacity of the biomass for single metal ions (around 1?mmol/g) was increased to 1.3?mmol/g in competitive adsorption, Pb(II) showing the highest Langmuir intensity constant. Considering its extremely high abundance and low cost, C. barbata may be potentially important in metal ion removal from contaminated water and industrial effluents.     

Removal of Pb(II) and Cd(II) ions from water by Fe and Ag nanoparticles prepared using electro-exploding wire technique

Purpose

This work aimed at investigating the adsorption of lead and cadmium onto Fe and Ag nanoparticles for use as a water contaminant removal agent as a function of particle type, sorbent concentration, and contact time.

Methods

Fe and Ag spherical nanoparticles were prepared in water by the lab-made electro-exploding wire (EEW) system and were investigated for their structure properties. Adsorption experiments were carried out at room temperature and pH 8.3 water solutions.

Results

The removal/adsorption of both Pb(II) and Cd(II) ions was found to be dependent on adsorbent dosage and contact time. Pb(II) adsorption onto Fe and Ag nanoparticles showed more or less similar efficiency and behavior. The kinetic data for the adsorption process obeyed pseudo second-order rate equations. The calculated equilibrium adsorption capacities (q _e) were 813 and 800 mg/g for Pb sorption onto Fe and Ag nanoparticles, respectively. Cd(II) ion adsorption onto Fe nanoparticles obeyed pseudo second-order rate equations with q _e equal to 242 mg/g, while their adsorption onto Ag nanoparticles obeyed pseudo first-order rate equations with q _e of 794 mg/g. The calculated q _es are in quite agreement with the experimental values. The removal/uptake mechanisms of metal ions involved interaction between the metal ion and the oxide/hydroxyl layer around the spherical metallic core of the nanoparticle in water medium.

Conclusion

Fe and Ag nanoparticles prepared using the EEW technique exhibited high potentials for the removal of metal ions from water with very high adsorption capacities, suggesting that the EEW technique can be enlarged to generate nanoparticles with large quantities for field or site water purification.     

Effects of organic acids on adsorption of lead onto montmorillonite,goethite and humic acid

Adsorption isotherms for Pb onto six soil components (quartz, feldspar, kaolinite, montmorillonite, goethite and humic acid) were studied. The influence of pH, EDTA and citric acid on the adsorption of Pb onto montmorillonite, goethite and humic acid were considered. Results indicate that the experimental data fit the Langmuir Adsorption Isotherm. The adsorption capacity for Pb at pH 6 was found to be in the order: humic acid (22.7 mg g(-1)) > goethite (11.04 mg g(-1)) > montmorillonite (10.4 mg g(-1)) > kaolinite (0.91 mg g(-1)) > feldspar (0.503 mg g(-1)) > quartz (0.148 mg g(-1)). Generally, the amount of Pb adsorbed onto montmorillonite, goethite and humic acid decreased with increasing concentrations of EDTA and citric acid and with increases in alkality. However, there were two exceptions: (1) addition of citric acid increased the amount of Pb adsorbed onto humic acid; and (2) the amount of Pb adsorbed onto goethite decreased with increasing pH in the presence of EDTA. Some mechanisms involved in the adsorption reactions are discussed.     

Preparation of alginate-chitosan hybrid gel beads and adsorption of divalent metal ions

Naturally occurring polysaccharides such as alginic acid and chitosan have been recognized as one of the most effective adsorbents to eliminating low levels of heavy metal ions from waste water stream. The present study intended to use alginic acid and chitosan simultaneously, which are expected to form a rigid matrix structure of beads due to electrostatic interaction between carboxyl groups on alginic acid and amino groups on chitosan, and to prepare alginate-chitosan hybrid gel beads. This could be achieved for the first time by using water-soluble chitosan, which was obtained by deacetylating chitin to 36-39% degree. The water-soluble chitosan dissolved in water could remain in solution in the presence of sodium alginate, and the homogeneous solution of chitosan and alginate was dispensed into a CuCl2 solution to give gel bead particles. The resultant beads were then reinforced by a cross-linking reaction of aldehyde groups on glutaraldehyde with amine groups on the chitosan. The cross-linking reaction made the beads durable under acidic conditions. The adsorption of Cu(II), Co(II), and Cd(II) on the beads was significantly rapid and reached at equilibrium within 10 min at 25 degrees C. Adsorption isotherms of the metal ions on the beads exhibited Freundlich and/or Langmuir behavior, contrary to gel beads either of alginate or chitosan showing a step-wise shape of adsorption isotherm.     

Adsorption/desorption properties of copper ions on the surface of iron-coated sand using BET and EDAX analyses

This study was conducted to develop a heating process for coating hydrated iron oxide on the sand surface to utilise the adsorbent properties of the coating and the filtration properties of the sand. BET and scanning electron microscope (SEM) analyses were used to investigate the surface properties of the coated layer. An energy dispersive X-ray (EDAX) technique of analysis was used for characterising metal adsorption sites on the iron-coated sand surface. The results indicated that the iron-coated sand had more micropores and higher specific surface area because of the attachment of iron oxide. Copper ions could penetrate into the micropores and mesopores of iron oxide on sand surface, and the regeneration of the iron-coated sand could be achieved by soaking with pH = 3.0 acid solution. Besides, the results of EDAX analysis showed that copper ions were chemisorbed on the surface of iron-coated sand. Results of the study developed an innovative technology for coating iron oxide on sand surface for the treatment of heavy metal in water.     

Removal of Pb(II), Cd(II), Cu(II), and Zn(II) by hematite nanoparticles: effect of sorbent concentration, pH, temperature, and exhaustion

Nanoparticles offer the potential to improve environmental treatment technologies due to their unique properties. Adsorption of metal ions (Pb(II), Cd(II), Cu(II), Zn(II)) to nanohematite was examined as a function of sorbent concentration, pH, temperature, and exhaustion. Adsorption experiments were conducted with 0.05, 0.1, and 0.5 g/L nanoparticles in a pH 8 solution and in spiked San Antonio tap water. The adsorption data showed the ability of nanohematite to remove Pb, Cd, Cu, and Zn species from solution with adsorption increasing as the nanoparticle concentration increased. At 0.5 g/L nanohematite, 100 % Pb species adsorbed, 94 % Cd species adsorbed, 89 % Cu species adsorbed and 100 % Zn species adsorbed. Adsorption kinetics for all metals tested was described by a pseudo second-order rate equation with lead having the fastest rate of adsorption. The effect of temperature on adsorption showed that Pb(II), Cu(II), and Cd(II) underwent an endothermic reaction, while Zn(II) underwent an exothermic reaction. The nanoparticles were able to simultaneously remove multiple metals species (Zn, Cd, Pb, and Cu) from both a pH 8 solution and spiked San Antonio tap water. Exhaustion experiments showed that at pH 8, exhaustion did not occur for the nanoparticles but adsorption does decrease for Cd, Cu, and Zn species but not Pb species. The strong adsorption coupled with the ability to simultaneously remove multiple metal ions offers a potential remediation method for the removal of metals from water.     

Adsorption and removal of As(V) and As(III) using Zr-loaded lysine diacetic acid chelating resin

An adsorption process for the removal of As(V) and As(III) was evaluated under various conditions using zirconium(IV) loaded chelating resin (Zr-LDA) with lysine-Nalpha,Nalpha diacetic acid functional groups. Arsenate ions strongly adsorbed in the pH range from 2 to 5, while arsenite was adsorbed between pH 7 and 10.5. The sorption mechanism is an additional complexation between arsenate or arsenite and Zr complex of LDA. Adsorption isotherm data could be well interpreted by Langmuir equation for As(V) at pH 4 and As(III) at pH 9 with a binding constant 227.93 and 270.47 dm3 mol(-1) and capacity constant 0.656 and 1.1843 mmol g(-1), respectively. Regeneration of the resin was carried out for As(V) using 1 M NaOH. Six adsorption/desorption cycles were performed without significant decrease in the uptake performance. Column adsorption studies showed that the adsorption of As(V) is more favorable compared to As(III), due to the faster kinetics of As(V) compared to As(III). Influence of the coexisting ions on the adsorption of As(V) and As(III) was studied. The applicability of the method for practical water samples was studied.     

Adsorption and cosorption of cadmium and glyphosate on two soils with different characteristics

Glyphosate [N-(phosphonomethyl)glycine] (GPS; H3G) is a widely used pesticide throughout the world. It affects metal behaviors in soil-plant system due to its functional groups, which react with metal ions to form metal complexes. Adsorption and cosorption of cadmium and glyphosate on a Wushan soil (WS soil, Anthrosol) and a Zhuanhong soil (ZH soil, Udic Ferrisol) as affect by solution pH were studied by means of batch adsorption experiments. It indicated that the adsorption quantity of Cd or glyphosate was highly relevant to soil characteristics. The WS soil had higher adsorption capacity of Cd than the ZH soil, due to its high organic matter content and cation exchange capacity (CEC). In contrast, the adsorption quantity of glyphosate on the WS soil was less than that on the ZH soil, because the WS soil has lower iron and aluminum oxides content but higher pH than the ZH soil. The herbicide glyphosate affected Cd adsorption on the two soils when they coexisted in a same soil solution, which was attributed to a glyphosate-induced pH-decrease and the corresponding decline in negative surface charges of the soil. Beside that, glyphosate reacted with solution Cd to form the water-soluble complexes that had lower affinity to soil surface in comparison with Cd itself. On the other hand, the presence of Cd in the soil solution also affected the adsorption of glyphosate on the soils. The presence of Cd increased adsorption quantity of glyphosate on the WS and ZH soils, which was resulted from the decrease of equilibrium solution pH caused by Cd2+ exchange with H+ ions of soil surface. In addition to that, glyphosate adsorption possibly takes place on sites where Cd was previously adsorbed and acted as a bridge between the soil and glyphosate.     

Removal of metal ions and humic acid from water by iron-coated filter media

Iron oxide is an excellent, regenerable adsorbent, and often controls free metals through adsorption reaction. The utilization of heating process for coating iron oxide on sand surface allowed the media to be used in a packed column. Iron-coated sand was investigated for adsorbing metal ions and natural organic matter from water by batch and column experiments. Chemical analysis (energy dispersive analysis of X-ray, EDAX) was used for characterizing the copper and lead adsorption sites on iron-coated sand. From the batch experiment results, the copper and lead ions could be removed simultaneously by the iron-coated sand in the competition adsorption system. The interaction between copper, lead ions and iron oxide on sand surface was primarily the chemical bonds. The maximum adsorption capacities of iron-coated sand for copper and lead were 0.259 mg Cu/g-sand and 1.211 mg Pb/g-sand, respectively. The presence of humic acid led to increase the adsorption of copper and lead. Results from column experiments indicated that the copper ions, lead ions and humic acid could be removed completely before the breakpoint. Consequently, the iron-coated sand may be applied for the adsorption/filtration of metal ions and natural organic matters from water.     

磷酸根和硫离子在纳米铁表面的竞争吸附

通过纳米铁对磷酸根和硫离子的单吸附和竞争吸附的研究,从吸附动力学和吸附等温线两个方面分析并验证了其吸附特性和模式。分析表明,相对于磷酸根,纳米铁对硫离子的吸附能力更强,在竞争条件下居优势地位。采用准一级和准二级吸附动力学方程对实验数据进行模拟分析,结果表明,纳米铁对磷酸根和硫离子的吸附符合二级动力学方程。吸附等温线分析采用Freundlich和Langmuir吸附等温线方程模拟分析,分析结果表明,纳米铁颗粒对磷酸根的吸附符合Freundlich吸附模式,而对硫离子的吸附符合Langmuir吸附模式。     

Removal of cyanotoxins from surface water resources using reusable molecularly imprinted polymer adsorbents

Introduction

Microcystins (MCs; cyclic heptapeptides) are produced by freshwater cyanobacteria and cause public health concern in potable water supplies. There are more than 60 types of MCs identified to date, of which MC-LR is the most common found worldwide. For MC-LR, the WHO has established a threshold value of 1???g?L^?1 for drinking water. The present MCs removal methods such as coagulation, flocculation, adsorption, and filtration showed low efficiency for removing dissolved MC fraction from surface waters to the stipulated limit prescribed by WHO based on MC health impacts. The search for cost-effective and efficient removal method is still warranted for remediation of dissolved MC-LR-contaminated water resources.

Materials and methods

Molecularly imprinted polymer (MIP) adsorbent has been prepared using non-covalent imprinting approach. Using MC-LR as a template, itaconic acid as a functional monomer, and ethylene glycol dimethacrylate as a cross-linking monomer, a MIP has been synthesized. Computer simulations were used to design effective binding sites for MC-LR binding in aqueous solutions. Batch binding adsorption assay was followed to determine binding capacity of MIP under the influence of environmental parameters such as total dissolved solids and pH.

Results and discussion

The adsorptive removal of MC-LR from lake water has been investigated using MIPs. The MIP showed excellent adsorption potential toward MC-LR in aqueous solutions with a binding capacity of 3.64???g?mg^?1 which is about 60% and 70% more than the commercially used powdered activated carbon (PAC) and resin XAD, respectively. Environmental parameters such as total organic carbon (represented as chemical oxygen demand (COD)) and total dissolved solids (TDS) showed no significant interference up to 300?mg?L^?1 for MC-LR removal from lake water samples. It was found that the binding sites on PAC and XAD have more affinity toward COD and TDS than the MC-LR. Further, the adsorption capacity of the MIP was evaluated rigorously by its repeated contact with fresh lake water, and it was found that the adsorption capacity of the MIP did not change even after seven adsorption/desorption cycles. The contaminated water of MC-LR (1.0???g?L^?1) of 3,640?L could be treated by 1?g of MIP with an estimated cost of US $1.5.

Conclusions

The adsorption capacity of the MIP is 40% more than commercially used PAC and resins and also the polymer showed reusable potential which is one of the important criteria in selection of cyanotoxins remediation methods.     

多孔水凝胶P（HEA/AMPS）对水溶液中Fe（Ⅲ）的吸附

以2-丙烯酸羟乙酯（HEA）和2-丙烯酰胺基-2-甲基丙磺酸（AMPS）为单体合成了聚合物水凝胶（PHEA/AMPS）,采用水凝胶对水溶液中Fe（Ⅲ）的吸附行为进行了研究。实验主要考察了聚合物组分、溶液pH、初始Fe（Ⅲ）浓度和吸附时间对水凝胶吸附作用的影响,并通过FT-IR和XPS分析了吸附前后水凝胶的变化。结果表明,当单体摩尔比AMPS∶HEA=1∶1,pH=2时,水凝胶对Fe（Ⅲ）的吸附容量最大。水凝胶对水溶液中Fe（Ⅲ）的吸附容量随着溶液中初始Fe3＋浓度的增加而增加,但当初始Fe3＋的浓度达到1 g/L时,吸附容量基本达到饱和。吸附等温线符合Langmuir等温线方程,吸附动力学符合准二级模型。FI-IR和XPS的分析表明,水凝胶的磺酸基和酰胺基是吸附Fe3＋的有效功能性基团,吸附机理为螯合和离子交换。     

Removal of Pb2+ from aqueous solution by adsorption on chemically modified muskmelon peel

A cost-effective biosorbent was prepared by a green chemical modification process from muskmelon peel by saponification with alkaline solution of Ca(OH)₂. Its adsorption behavior for lead ions was investigated and found to exhibit excellent adsorption properties. Results showed that the optimal equilibrium pH range for 100 % adsorption is from 4 up to 6.4. Adsorption equilibrium was attained within 10 min. The adsorption process can be described well by Langmuir model and pseudo-second-order kinetics equation, respectively. The maximum adsorption capacity for lead ions was found to be 0.81 mol/kg. Pectic acid contained in the muskmelon peel is the main factor responsible for the uptake of lead ions onto the gel, and the chemical modification process presented in this study can be assumed effective to prepare other similar biomaterials. The large adsorption capacity and the fast adsorption rate indicated that chemically saponified muskmelon peel gel in present study has great potential to be used as a cost-effective adsorbent for the removal of lead ions from the water.     

Surface charge and adsorption from water onto quartz sand of humic acid

The surface charge of humic acid under different conditions of ionic strength, pH, and the presence of various cationic ions (Cu(2+), Zn(2+), Ba(2+), and Ca(2+)) was determined by a titration method using a cationic polyelectrolyte as titrant. Adsorption isotherms in batch experiments of the polymer from water onto quartz sand were determined at 20 degrees C, 40 degrees C, and 60 degrees C and under different conditions of ionic strength, pH, and the presence of various cationic ions (Cu(2+), Zn(2+), Ba(2+), and Ca(2+)). The data indicate significant decrease of humic acid surface charge by decreasing the pH value from 10.0 to 4.1. Similar decrease of humic acid surface charge was observed by increasing either the ionic strength or the affinity of the divalent cation toward the humic acid. At ambient temperature the adsorption of humic acid on the quartz sand seems to be controlled mainly by electrical interaction between the organic particle and the solid substrate. A correlation is found between the surface charge and the adsorbed amount of the polymer, the adsorbed amount increases when the surface charge of humic acid decreases. The increase of the adsorbed amount with the temperature suggests that adsorption process is endothermic.     

Removal of arsenic(V) from aqueous solutions using iron-oxide-coated modified activated carbon.

Removal of arsenic(V) from aqueous solutions was evaluated with the following three different sorption materials: coal-based activated carbon 12 x 40 (activated carbon), iron(II) oxide (FeO)/activated carbon-H, and iron oxide. The apparent characteristics and physical chemistry performances of these adsorbents were investigated by X-ray diffraction, nitrogen adsorption, and scanning electronic microscope. Also, batch experiments for arsenic removal were performed, and the effects of pH value on arsenic(V) removal were studied. The results suggest that the main phases of the iron oxide surface are magnetite, maghemite, hematite, and goethite; fine and uniform iron oxide particles can cover activated carbon surfaces and affect the surface area or pore structures of activated carbon; adsorption kinetics obey a pseudo-first-order rate equation; and adsorption capacities of adsorbents are affected by the values of pH. The optimum value of pH for iron oxide lies in a narrow range between 4.0 and 5.5, and arsenic(V) removal by FeO/activated carbon-H is ideal and stable in the pH range 3 to 7, while activated carbon has the lowest adsorption capacity in the entire pH range. Also, the adsorption characteristics of FeO/activated carbon-H composites and virgin activated carbon match well the Langmuir adsorption model, while those of iron oxide fit well the Freundlich adsorption model.     

The removal of arsenate from water using iron-modified diatomite (D-Fe): isotherm and column experiments

Iron hydroxide supported onto porous diatomite (D-Fe) is a low-cost material with potential to remove arsenic from contaminated water due to its affinity for the arsenate ion. This affinity was tested under varying conditions of pH, contact time, iron content in D-Fe and the presence of competitive ions, silicate and phosphate. Batch and column experiments were conducted to derive adsorption isotherms and breakthrough behaviours (50 μg L^?1) for an initial concentration of 1,000 μg L^?1. Maximum capacity at pH 4 and 17 % iron was 18.12–40.82 mg of arsenic/g of D-Fe and at pH 4 and 10 % iron was 18.48–29.07 mg of arsenic/g of D-Fe. Adsorption decreased in the presence of phosphate and silicate ions. The difference in column adsorption behaviour between 10 % and 17 % iron was very pronounced, outweighing the impact of all other measured parameters. There was insufficient evidence of a correlation between iron content and arsenic content in isotherm experiments, suggesting that ion exchange is a negligible process occurring in arsenate adsorption using D-Fe nor is there co-precipitation of arsenate by rising iron content of the solute above saturation.     

Catalytic effect of soil colloids on the reaction between CrVI and p-methoxyphenol

Adsorption of CrVI and p-methoxyphenol (PMP) on soil colloids at different pH media was studied. The resulting k1 and n of 1.89 x 10(2) and 0.53 (r2 = 0.99) and k2 and b of 0.13 and 1.25 x 10(3) (r2 = 0.96) were obtained from Freundlich (Q = k1Caqn) and Langmuir [Q = k2bCaq/(1 + k2Caq)] simulation equations, respectively, for CrVI adsorption on soil colloids (pH 4.20). The adsorption of PMP on soil colloids in pH 5.72 media was simulated by five different equations and the results indicated that the Fritz-Schluender one (r2 = 1.00) was the most suitable among them. Adsorption quantity of CrVI and PMP on colloids increased with increasing acidity in the pH range of 3.5-9.0. Study of CrVI adsorption kinetics indicated that the adsorption equilibrium of CrVI was reached rapidly within 2 h. In pure aqueous solution, CrVI reduction by PMP was observed only when the media's pH was lower than 4.0. Oxidation and reduction reaction between CrVI and p-methoxyphenol obviously occurred when soil colloids were involved in this system, even at pH > or = 7.0, which strongly suggested that minerals in soil colloids acted as catalysts to speed the reaction of CrVI and PMP. The oxidized product of PMP by CrVI, extracted by chloroform in acid media and analyzed by gas chromatography-mass spectrometry, was identified as benzoquinone. The reaction included two steps of one electron process.     

Novel chitosan/PVA/zerovalent iron biopolymeric nanofibers with enhanced arsenic removal applications

Enhanced removal application of both forms of inorganic arsenic from arsenic-contaminated aquifers at near-neutral pH was studied using a novel electrospun chitosan/PVA/zerovalent iron (CPZ) nanofibrous mat. CPZ was carefully examined using scanning electron microscopy (SEM) equipped with energy-dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), atomic fluorescence spectroscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermal gravimetric analysis (TGA). Application of the adsorbent towards the removal of total inorganic arsenic in batch mode has also been studied. A suitable mechanism for the adsorption has also been discussed. CPZ nanofibers mat was found capable to remove 200.0?±?10.0 mg g^?1 of As(V) and 142.9?±?7.2 mg g^?1 of As(III) from aqueous solution of pH 7.0 at ambient condition. Addition of ethylenediaminetetraacetic acid (EDTA) enabled the stability of iron in zerovalent state (ZVI). Enhanced capacity of the fibrous mat could be attributed to the high surface area of the fibers, presence of ZVI, and presence of functional groups such as amino, carboxyl, and hydroxyl groups of the chitosan and EDTA. Both Langmuir and Freundlich adsorption isotherms were applicable to describe the removal process. The possible mechanism of adsorption has been explained in terms of electrostatic attraction between the protonated amino groups of chitosan/arsenate ions and oxidation of arsenite to arsenate by Fentons generated from ZVI and subsequent complexation of the arsenate with the oxidized iron. These CPZ nanofibrous mats has been prepared with environmentally benign naturally occurring biodegradable biopolymer chitosan, which offers unique advantage in the removal of arsenic from contaminated groundwater.