Arsenic removal in polluted water using pillared clays

More than 170 million individuals have been influenced by arsenic (As) because of the ingestion of As-polluted groundwater. The presence of As in water bodies, particularly groundwater, has been found to become a widespread issue in the past few decades. Because arsenic causes extreme wellbeing impacts, even at a low concentration in drinking water, the innovations of As removal from contaminated water are of significant importance. Traditional strategies, for example, reverse osmosis, ion exchange, and electro-dialysis are generally utilized for the remediation of As-polluted water; however, the high cost and/or sludge production restricts their application in less-developed areas. The utilization of adsorbents acquired from natural materials has been explored as an alternative for the costly techniques for As removal. This paper aims to review the past and current developments in using naturals adsorbents or modified natural materials for arsenic removal and show the different parameters, which may influence the As removal effectiveness of the natural adsorbent, such as contact time, adsorbent dosage, flow rate, pH, reusability, temperature, and influence of others ions.

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Preparation of an Iron Oxide Modified Montmorillonite for Removal of Arsenic in Waters

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.156-157.849 ◽

2010 ◽

Vol 156-157 ◽

pp. 849-853 ◽

Cited By ~ 2

Author(s):

Hai Fei Liu ◽

De Ren Miao ◽

Fei Liu

Keyword(s):

Iron Oxide ◽

Arsenic Removal ◽

Polluted Water ◽

X Ray Diffraction ◽

Characteristic Analysis ◽

Experimental Conditions ◽

Thermal Gravimetry ◽

Modified Montmorillonite ◽

Removal Of Arsenic ◽

Better Than

Most concerns have focused on the arsenic (As) contamination in wastewater. Montmorillonite (MMT) has been proved to be a good adsorbent for removal heavy metals existing as cation in ground water while it is invalid for anions. However, arsenic usually exists as anions in aqueous. Accordingly, suitable modifications on MMT need to be done before using. This paper presents the results that a kind of commercial MMT has been modified by iron oxides under normal and inverse titration conditions. The x-ray diffraction (XRD), Thermal Gravimetry Analysis and Differential Thermal Analysis (TGA-DTA) and SBET analysis have been employed to elucidate the modification mechanisms. Modification characteristic analysis illustrated that the iron oxide associated with MMT by coated style as polymerization of hydroxyl-Fe (Fe (OH) 3) under inverse titration condition. Under normal titration condition, on the other hand, the iron oxide associated with MMT predominant by intercalation as goethite (FeOOH). The arsenic removal efficiencies of different modified products for polluted water have also been verified by batch experiments. Results proved that Iron oxide modified MMT on the removal efficiency of arsenic significantly increased and the normal titration is better than inverse titration as indicated by the arsenic removal ratios under the same experimental conditions. Based on these results, the iron oxide modified MMT by normal titration procedure is a promising material for removal arsenic in wastewaters.

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Influence of Various Factors on Arsenic Removal Using Ferruginous Manganese Ore

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.2753 ◽

2011 ◽

Vol 71-78 ◽

pp. 2753-2758 ◽

Cited By ~ 2

Author(s):

Yong Bing Huang ◽

Li Li Wang ◽

Shu Xin Tu ◽

Xiu Ying Liu ◽

Xiao Juan Li ◽

...

Keyword(s):

Reaction Time ◽

Removal Efficiency ◽

Competitive Adsorption ◽

Arsenic Removal ◽

Orthogonal Experiment ◽

Polluted Water ◽

Manganese Ore ◽

Electrostatic Repulsion ◽

Temperature Time ◽

Coexisting Ions

This paper dealt with the influence of various factors on As(Ⅲ) and As(Ⅴ) removal using ferruginous manganese ore, including environmental factors (temperature, time, light, pH) and coexisting ions(HCO3-,CO32-,Cl-,HPO42-,SiO32-,SO42-,Mg2+,Ca2+,Fe3+). The comprehensive influence of various factors was also studied in orthogonal experiment. The results showed that the removal efficiency of As(Ⅲ) was up to 90.26%, while As(Ⅴ) was only 79.88%, under the conditions of that manganese ore dosage was 0.1000g per 50ml polluted water, reaction time was 1h, pH was 3.05, the concentration of arsenic was 204.45ug/l. Lower pH could achieve higher removal efficiency. Illumination was little beneficial to the removal efficiency. SiO32-, HPO42-, CO32- and HCO3- could reduce the efficiency, due to competitive adsorption and electrostatic repulsion. The results of orthogonal experiment indicated that SiO32- and HPO42- were the greatest competitors with arsenic for adsorptive sites on the manganese ore, while temperature and time had no significant effect on arsenic removal.

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Research Progress on Biological Removal of Arsenic Technology

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.253-255.1040 ◽

2012 ◽

Vol 253-255 ◽

pp. 1040-1043

Author(s):

Xing Sheng Kang ◽

Qiang Su ◽

Jun Shen ◽

Yi Li

Keyword(s):

High Efficiency ◽

Arsenic Removal ◽

Environmental Concern ◽

Low Cost ◽

Research Progress ◽

Polluted Water ◽

Biological Removal ◽

Global Environmental ◽

Removal Technology ◽

Removal Of Arsenic

Arsenic is a toxic element, which is harmful to environment and human health. How to treat arsenic polluted water has become a global environmental concern. Current biological arsenic removal technology was researched base on plants, microorganisms and so on. Biological removal of arsenic technology has high efficiency, low cost, and low secondary pollution, which will be the most promising technology.

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Application of Monoclinic Bismuth Vanadate in Photooxidation of Arsenic-Polluted Water

Transactions of the ASABE ◽

10.13031/trans.13754 ◽

2020 ◽

Vol 63 (6) ◽

pp. 1649-1655

Author(s):

Miaomiao Chen ◽

Yi Li ◽

Hong Pan ◽

Jiuwei Teng ◽

Ganesh Bora ◽

...

Keyword(s):

Visible Light ◽

Arsenic Removal ◽

Inorganic Arsenic ◽

Bismuth Vanadate ◽

Light Irradiation ◽

Polluted Water ◽

List Type ◽

Trivalent Arsenic ◽

Keywords Arsenic ◽

Pentavalent Arsenic

HighlightsPhotooxidation of trivalent arsenic to pentavalent arsenic was catalyzed by s-m BiVO4 under visible light irradiation.The roles of catalyst, light, and oxygen were investigated.The photooxidation mechanism was studied, and a possible reaction route is proposed.Abstract. Oxidation is a necessary step for inorganic arsenic removal. In this study, monoclinic bismuth vanadate (BiVO4) was synthesized to photooxidize trivalent arsenic to pentavalent arsenic in water in the presence of light and oxygen. Light irradiation initiates photooxidation after physical absorption of arsenite on BiVO4. Addition of oxygen slightly improved the photooxidation efficiency. Photooxidation parameters were optimized; 2.6 mM of BiVO4 synthesized at pH 2 was effective to photooxidize 0.1 M of arsenite in alkaline solution, and 99.8% removal of trivalent arsenic was achieved with a photooxidation efficiency of 85.5%. Photooxidation by BiVO4 might be initiated by hydroxyl radicals resulting from irradiation by visible light. Appropriate BiVO4 morphology and alkalinity of the reaction mixture facilitated photooxidation. Keywords: Arsenic, BiVO4, Photooxidation, Speciation.

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Arsenic removal from drinking water using low-pressure nanofiltration under various operating conditions

Water Practice & Technology ◽

10.2166/wpt.2018.042 ◽

2018 ◽

Vol 13 (2) ◽

pp. 295-302 ◽

Cited By ~ 3

Author(s):

M. Harfoush ◽

S. A. Mirbagheri ◽

M. Ehteshami ◽

S. Nejati

Keyword(s):

Drinking Water ◽

Arsenic Removal ◽

Arsenic Concentration ◽

Inorganic Arsenic ◽

Low Pressure ◽

Operating Conditions ◽

Polluted Water ◽

Initial Concentration ◽

Wide Range ◽

Arsenite Removal

Abstract Currently, one of the main environmental concerns is the toxicity caused by arsenic. Arsenic-polluted water can cause many human health problems including various cancerous diseases. In natural water, inorganic arsenic can be found in the forms of arsenite and arsenate, which have been found in several Iranian provinces – e.g., East Azerbaijan, Kurdistan, and the city of Bijar – in high concentrations. Modern nanofiltration (NF) technology enables a wide range of water resource pollutants to be controlled efficiently. In this study, in an attempt to enhance arsenic removal (both arsenite and arsenate) from drinking water using low pressure NF, operating conditions like arsenic concentration, the trans-membrane pressure applied, and a range of different temperatures have all been considered. The highest arsenate removal achieved was 94% with an initial concentration of 500 μg/L, at 7 bar pressure, and 28 °C. The highest arsenite removal was 90%, with an initial concentration of 100 μg/L, at 5 bar pressure, and also at 28 °C. Increasing the pressure had a positive effect on the removal of both species, however, increasing the temperature had negative impacts. It was always found that arsenate removal was better than arsenite removal.

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Assessment of Water Mimosa (Neptunia oleracea Lour.) Morphological, Physiological, and Removal Efficiency for Phytoremediation of Arsenic-Polluted Water

Plants ◽

10.3390/plants9111500 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1500

Author(s):

Narges Atabaki ◽

Noor Azmi Shaharuddin ◽

Siti Aqlima Ahmad ◽

Rosimah Nulit ◽

Rambod Abiri

Keyword(s):

Lipid Peroxidation ◽

Arsenic Removal ◽

Dry Weight ◽

Aquatic Systems ◽

Polluted Water ◽

Tolerance Index ◽

Growth Responses ◽

Relative Growth ◽

Arsenic Accumulation ◽

Relative Water

Arsenic is considered to be a toxic and heavy metal that exists in drinking water and can lead to acute biotoxicity. Water mimosa (Neptunia oleracea) has been widely identified as a feasible phytoremediator to clean up aquatic systems. In the current study, the phytoremediation potential of water mimosa exposed to different concentrations of sodium heptahydrate arsenate (Na2HAsO4·7H2O) was tested. A number of plant physiological and growth responses such as height of frond, existence of green leaves, relative growth rate, relative water content, tolerance index, decrease in ratio of biomass and ratio of dry weight, chlorophyll content, photosynthesis rate, intercellular CO2 concentrations, stomatal conductance, air pressure deficit, transpiration rate, proline and lipid peroxidation, as well as arsenic accumulation and removal efficacy were analyzed. The micromorphological analysis results confirmed water mimosa’s tolerance of up to 30 ppm of arsenic treatment. The results obtained from the chlorophyll and gas exchange content also showed severe damage by arsenic at doses higher than 30 ppm. In addition, the highest arsenic accumulation and arsenic removal efficacy were observed at the range of 30–60 ppm. An analysis of proline and lipid peroxidation content confirmed water mimosa’s tolerance of up to 30 ppm of arsenic. The scanning electron microscopy (SEM) and X-ray spectroscopy (EDX) and analysis also confirmed the accumulation of arsenic as shown by the deformation of water mimosa tissues. The results showed that water mimosa is a reliable bioremediator for removing arsenic from aquatic systems.

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Hydrous cerium oxides coated glass fiber for efficient and long-lasting arsenic removal from drinking water

Journal of Advanced Ceramics ◽

10.1007/s40145-020-0435-0 ◽

2021 ◽

Vol 10 (2) ◽

pp. 247-257 ◽

Cited By ~ 1

Author(s):

Ronghui Li ◽

Weiyi Yang ◽

Shuang Gao ◽

Jianku Shang ◽

Qi Li

Keyword(s):

Experimental Data ◽

Drinking Water ◽

Glass Fiber ◽

Arsenic Removal ◽

World Health ◽

Polluted Water ◽

Column Test ◽

Order Model ◽

Treated Water ◽

Cerium Oxides

AbstractA novel arsenic adsorbent with hydrous cerium oxides coated on glass fiber cloth (HCO/GFC) was synthesized. The HCO/GFC adsorbents were rolled into a cartridge for arsenic removal test. Due to the large pores between the glass fibers, the arsenic polluted water can flow through easily. The arsenic removal performance was evaluated by testing the equilibrium adsorption isotherm, adsorption kinetics, and packed-bed operation. The pH effects on arsenic removal were conducted. The test results show that HCO/GFC filter has high As(V) and As(III) removal capacity even at low equilibrium concentration. The more toxic As(III) in water can be easily removed within a wide range of solution pH without pre-treatment. Arsenic contaminated ground-water from Yangzong Lake (China) was used in the column test. At typical breakthrough conditions (the empty bed contact time, EBCT = 2 min), arsenic researched breakthrough at over 24,000 bed volumes (World Health Organization (WHO) suggested that the maximum contaminant level (MCL) for arsenic in drinking water is 10 mg/L). The Ce content in the treated water was lower than 5 ppb during the column test, which showed that cerium did not leach from the HCO/GFC material into the treated water. The relationship between dosage of adsorbents and the adsorption kinetic model was also clarified, which suggested that the pseudo second order model could fit the kinetic experimental data better when the adsorbent loading was relatively low, and the pseudo first order model could fit the kinetic experimental data better when the adsorbent loading amount was relatively high.

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