References
  -  U. Asghar, F. Perveen, S.K. Alvi, F.A. Khan, I. Siddqui,
    T.H. Usmani, Contamination of arsenic in public water supply
    schemes of Larkana and Mirpurkhas Districts of Sind, J. Chem.
    Soc. Pak., 28 (2006) 130–135. 
-  J.G. Hering, P.-Y. Chen, J.A. Wilkie, M. Elimelech, S. Liang,
    Arsenic removal by ferric chloride, J. AWWA,
    88 (1996) 155–167. 
-  P. Askari, A. Faraji, G. Khayatian, S. Mohebbi, Effective
    ultrasound-assisted removal of heavy metal ions As(III),
    Hg(II), and Pb(II) from aqueous solution by new MgO/CuO
	  and MgO/MnO2 nanocomposites, J. Iran Chem. Soc., 14 (2017)
  613–621. 
-  S. Zavareh, M. Zarei, F. Darvishi, H. Azizi, As(III) adsorption
    and antimicrobial properties of Cu–chitosan/alumina
    nanocomposite, Chem. Eng. J., 273 (2015) 610–621. 
-  C. Babu, B. Palanisamy, B. Sundaravel, K. Shanthi,
    V. Murugesan, Dihalogen crosslinked Fe3O4-reduced graphene
    oxide nanocomposites for arsenic and mercury adsorption,
  Sci. Adv. Mater., 7 (2015) 794–805. 
-  D. Chakraborti, M.M. Rahman, B. Das, A. Chatterjee, D. Das,
    B. Nayak, A. Pal, U.K. Chowdhury, S. Ahmed, 
 B.K. Biswas,
    Groundwater arsenic contamination and its health effects in
    India, Hydrogeol. J., 25 (2017) 1165–1181.
-  A. Azizullah, M.N.K. Khattak, P. Richter, D.-P. Häder, Water
    pollution in Pakistan and its impact on public health—a review,
    Environ. Int., 37 (2011) 479–497. 
-  M. Bibi, M.Z. Hashmi, R.N. Malik, Human exposure to arsenic
    in groundwater from Lahore district, Pakistan, Environ. Toxicol.
    Pharmacol., 39 (2015) 42–52. 
-  A.S. Qureshi, Climate Change and Water Resources in
    South Asia, AA Balkema Publishers, Leiden, 2005, 
 pp. 197–230.
-  R. Nickson, J. McArthur, B. Shrestha, T. Kyaw-Myint, D. Lowry,
    Arsenic and other drinking water quality issues, Muzaffargarh
    District, Pakistan, Appl. Geochem., 20 (2005) 55–68. 
-  S. Muhammad, M.T. Shah, S. Khan, Arsenic health risk
    assessment in drinking water and source apportionment using
    multivariate statistical techniques in Kohistan region, northern
    Pakistan, Food Chem. Toxicol., 48 (2010) 2855–2864. 
-  M. Islam-Ul-Haq, N. Deedar, H. Wajid, Groundwater Arsenic
    Contamination—A Multi Directional Emerging Threat to Water
    Scarce Areas of Pakistan, 6th International IAHS Groundwater
    Quality Conference, Fremantle, Western Australia, 2007. 
-  A.Z.M. Badruddoza, Z.B.Z. Shawon, W.J.D. Tay, K. Hidajat,
    M.S. Uddin, Fe3O4 cyclodextrin polymer nanocomposites for
    selective heavy metals removal from industrial wastewater,
  Carbohydr. Polym., 91 (2013) 322–332. 
-  S. Sobhani, M. Bazrafshan, A.A. Delluei, Z.P. Parizi, Phospha-
    Michael addition of diethyl phosphite
 to α, β-unsaturated
    malonates catalyzed by nano γ-Fe2O3-pyridine based catalyst
    as a new magnetically recyclable heterogeneous organic base,
    Appl. Catal., A, 454 (2013) 145–151.
-  A. Farooqi, H. Masuda, N. Firdous, Toxic fluoride and arsenic
    contaminated groundwater in the Lahore and Kasur districts,
    Punjab, Pakistan and possible contaminant sources, Environ.
    Pollut., 145 (2007) 839–849. 
-  S. Iftekhar, M.U. Farooq, M. Sillanpää, M.B. Asif, R. Habib,
    Removal of Ni(II) using multi-walled carbon nanotubes
    electrodes: relation between operating parameters and
    capacitive deionization performance, Arabian J. Sci. Eng.,
    42 (2017) 235–240. 
-  S. Iftekhar, V. Srivastava, M. Sillanpää, Enrichment of
    lanthanides in aqueous system by cellulose based silica
    nanocomposite, Chem. Eng. J., 320 (2017) 151–159. 
-  R.J. Gohari, W. Jye Lau, T. Matsuura, A.F. Ismail, Remediation
    of Heavy Metals in the Environment, CRC Press, Boca Raton,
    Florida, USA, 2016, pp. 413–438. 
-  P. Brandhuber, G. Amy, Alternative methods for membrane
    filtration of arsenic from drinking water, Desalination, 117(1998)
    1–10. 
-  A.A. Alswat, M.B. Ahmad, T.A. Saleh, Zeolite modified with
    copper oxide and iron oxide for lead and arsenic adsorption
    from aqueous solutions, J. Water Supply Res. Technol. AQUA,
    65 (2016) 465–479. 
-  M. Yang, T.-J. Jiang, Z. Guo, J.-H. Liu, Y.-F. Sun, X. Chen,
    X.-J. Huang, Sensitivity and selectivity sensing cadmium(II)
    using amination functionalized porous SnO2 nanowire bundlesroom
    temperature ionic liquid nanocomposite: combined
    efficient cation capture with control experimental conditions,
  Sens. Actuators, B, 240 (2017) 887–894. 
-  S. Carfagna, N. Lanza, G. Salbitani, A. Basile, S. Sorbo, V. Vona,
    Physiological and morphological responses of lead or cadmium
    exposed Chlorella sorokiniana 211–8K (Chlorophyceae),
    SpringerPlus, 2 (2013) 147, doi:10.1186/2193-1801-2-147. 
-  D. Mohan, C.U. Pittman Jr., Arsenic removal from water/wastewater using adsorbents—a critical review, 
 J. Hazard.
    Mater., 142 (2007) 1–53.
-  S. Zhou, D. Wang, H. Sun, J. Chen, S. Wu, P. Na, Synthesis,
    characterization, and adsorptive properties of magnetic
    cellulose nanocomposites for arsenic removal, Water Air Soil
    Pollut., 225 (2014) 1945. 
-  M. Fanadzo, D. Zireva, E. Dube, A. Mashingaidze, Evaluation
    of various substrates and supplements for biological efficiency
    of Pleurotus sajor-caju and Pleurotus ostreatus, Afr. J. Biotechnol.,
    9 (2010) 2756–2761. 
-  H. Zhu, Y. Jia, X. Wu, H. Wang, Removal of arsenic from water
    by supported nano zero-valent iron on activated carbon,
    J. Hazard. Mater., 172 (2009) 1591–1596. 
-  C. Kamala, K. Chu, N. Chary, P. Pandey, S. Ramesh, A. Sastry,
    K.C. Sekhar, Removal of arsenic(III) from aqueous solutions
    using fresh and immobilized plant biomass, Water Res.,
    39 (2005) 2815–2826. 
-  A.A. Alswata, M.B. Ahmad, N.M. Al-Hada, H.M. Kamari,
    M.Z.B. Hussein, N.A. Ibrahim, Preparation of zeolite/zinc oxide
    nanocomposites for toxic metals removal from water, Results
    Phys., 7 (2017) 723–731. 
-  R. Attinti, D. Sarkar, K. Barrett, R. Datta, Adsorption of arsenic(V)
    from aqueous solutions by goethite/silica nanocomposite,
    Int. J. Environ. Sci. Technol., 12 (2015) 3905–3914. 
-  C.-H. Liu, Y.-H. Chuang, T.-Y. Chen, Y. Tian, H. Li, M.-K. Wang,
    W. Zhang, Mechanism of arsenic adsorption on magnetite
    nanoparticles from water: thermodynamic and spectroscopic
    studies, Environ. Sci. Technol., 49 (2015) 7726–7734. 
-  J.A. Gomes, P. Daida, M. Kesmez, M. Weir, H. Moreno,
    J.R. Parga, G. Irwin, H. McWhinney, T. Grady, E. Peterson,
    Arsenic removal by electrocoagulation using combined Al–Fe
    electrode system and characterization of products, J. Hazard.
    Mater., 139 (2007) 220–231. 
-  T. Sun, Z. Zhao, Z. Liang, J. Liu, W. Shi, F. Cui, Efficient As(III)
    removal by magnetic CuO-Fe3O4 nanoparticles through photooxidation
    and adsorption under light irradiation, J. Colloid
  Interface Sci., 495 (2017) 168–177. 
-  B. Chen, Z. Zhu, J. Ma, M. Yang, J. Hong, X. Hu, Y. Qiu, J. Chen,
    One-pot, solid-phase synthesis of magnetic multiwalled carbon
    nanotube/iron oxide composites and their application in arsenic
    removal, J. Colloid Interface Sci., 434 (2014) 9–17. 
-  J. Tuček, R. Prucek, J. Kolařík, G. Zoppellaro, M. Petr, J. Filip,
    V.K. Sharma, R. Zbořil, Zero-valent iron nanoparticles reduce
    arsenites and arsenates to As(0) firmly embedded in core–shell superstructure: challenging strategy of arsenic treatment
    under anoxic conditions, ACS Sustainable Chem. Eng., 5 (2017)
    3027–3038. 
-  N. Ponomarev, Synthesis of Novel Cellulose Based
    Nanocomposites by Green Methods and Their Possible use as
    Adsorbents, School of Engineering Science Laboratory of Green
    Chemistry, Lappeenranta University of Technology, Finland,
    2017. 
-  M. Auffan, J. Rose, O. Proux, D. Borschneck, A. Masion,
    P. Chaurand, J.-L. Hazemann, C. Chaneac, J.-P. Jolivet,
    M.R. Wiesner, Enhanced adsorption of arsenic onto maghemites
    nanoparticles: As(III) as a probe of the surface structure and
    heterogeneity, Langmuir, 24 (2008) 3215–3222. 
-  I. Andjelkovic, D.N. Tran, S. Kabiri, S. Azari, M. Markovic,
    D. Losic, Graphene aerogels decorated with α-FeOOH
    nanoparticles for efficient adsorption of arsenic from
    contaminated waters, ACS Appl. Mater. Interfaces, 7 (2015)
    9758–9766. 
-  H. Li, C. Shan, Y. Zhang, J. Cai, W. Zhang, B. Pan, Arsenate
    adsorption by hydrous ferric oxide nanoparticles embedded in
    cross-linked anion exchanger: effect of the host pore structure,
    ACS Appl. Mater. Interfaces, 8 (2016) 3012–3020. 
-  K. Grover, S. Komarneni, H. Katsuki, Uptake of arsenite by
    synthetic layered double hydroxides, Water Res., 43 (2009)
    3884–3890. 
-  E. Otgonjargal, Y.-S. Kim, S.-M. Park, K. Baek, J.-S. Yang, Mn–Fe
    layered double hydroxides for adsorption of As(III) and As(V),
    Sep. Sci. Technol., 47 (2012) 2192–2198. 
-  Q. Wang, Q. Lin, Q. Li, K. Li, L. Wu, S. Li, H. Liu, As(III) removal
    from wastewater and direct stabilization 
 by in-situ formation of
    Zn-Fe layered double hydroxides, J. Hazard. Mater., 403 (2021)
    123920, doi:10.1016/j.jhazmat.2020.123920.
-  A. Abo Markeb, A. Alonso, A.D. Dorado, A. Sánchez,
    X. Font, Phosphate removal and recovery from water using
    nanocomposite of immobilized magnetite nanoparticles on
    cationic polymer, Environ. Technol., 37 (2016) 2099–2112. 
-  S. Ahmad, Water Resources Development and Management
    in Pakistan, The Pakistan Development Review Part II (Winter
    2007), pp. 911–937. 
-  J. Cai, L. Zhang, Rapid dissolution of cellulose in LiOH/urea
    and NaOH/urea aqueous solutions, Macromol. Biosci., 5 (2005)
    539–548. 
-  S. Iftekhar, V. Srivastava, M. Sillanpää, Synthesis and application
    of LDH intercalated cellulose nanocomposite for separation of
    rare earth elements (REEs), Chem. Eng. J., 309 (2017) 130–139. 
-  S.-M. Li, N. Jia, J.-F. Zhu, M.-G. Ma, R.-C. Sun, Synthesis
    of cellulose–calcium silicate nanocomposites in ethanol/
    water mixed solvents and their characterization, Carbohydr.
    Polym., 80 (2010) 270–275. 
-  M.-G. Ma, F. Deng, K. Yao, Manganese-containing cellulose
    nanocomposites: the restrain effect of cellulose treated with
    NaOH/urea aqueous solutions, Carbohydr. Polym., 111 (2014)
    230–235. 
-  R. Buchanan, H. Caspers, J. Murphy, Lattice vibration spectra of
  Mg(OH)2 and Ca(OH)2, Appl. Opt., 2 (1963) 1147–1150. 
-  M. Thommes, K. Kaneko, A.V. Neimark, J.P. Olivier,
    F. Rodriguez-Reinoso, J. Rouquerol, K.S. Sing, Physisorption of
    gases, with special reference to the evaluation of surface area
    and pore size distribution (IUPAC Technical Report), Pure
    Appl. Chem., 87 (2015) 1051–1069. 
-  I.A. Udoetok, R.M. Dimmick, L.D. Wilson, J.V. Headley,
    Adsorption properties of cross-linked 
 cellulose-epichlorohydrin
    polymers in aqueous solution, Carbohydr. Polym., 136 (2016)
    329–340.
-  M. Lim, G.-C. Han, J.-W. Ahn, K.-S. You, H.-S. Kim, Leachability of
    arsenic and heavy metals from mine tailings of abandoned metal
    mines, Int. J. Environ. Res. Public Health, 6 (2009) 2865–2879. 
-  G. Vijayakumar, R. Tamilarasan, M. Dharmendirakumar,
    Adsorption, kinetic, equilibrium and thermodynamic studies on
    the removal of basic dye Rhodamine-B from aqueous solution
    by the use of natural adsorbent perlite, J. Mater. Environ. Sci.,
    3 (2012) 157–170. 
-  S. Muryanto, S.D. Hadi, Adsorption laboratory experiment
    for undergraduate chemical engineering: introducing kinetic,
    equilibrium and thermodynamic concepts, IOP Conf. Ser.: Mater.
    Sci. Eng., 162 (2016) 012004, doi: 10.1088/1757-899X/162/1/012004. 
-  Y.-S. Ho, Review of second-order models for adsorption
    systems, J. Hazard. Mater., 136 (2006) 681–689. 
-  C. Qing, Study on the adsorption of lanthanum(III) from
    aqueous solution by bamboo charcoal, J. Rare Earths, 28 (2010)
    125–131. 
-  Q. Yuan, N. Li, Y. Chi, W. Geng, W. Yan, Y. Zhao, X. Li, B. Dong,
    Effect of large pore size of multifunctional mesoporous
    microsphere on removal of heavy metal ions, J. Hazard. Mater.,
    254 (2013) 157–165. 
-  G.P. Gillman, A simple technology for arsenic removal
    from drinking water using hydrotalcite, Sci. Total Environ.,
    366 (2006) 926–931. 
-  O.S. Thirunavukkarasu, T. Viraraghavan, K.S. Subramanian,
    O. Chaalal, M.R. Islam, Arsenic removal in drinking water—
    impacts and novel removal technologies, Energy Sources,
    27 (2005) 209–219. 
-  H. Genç-Fuhrman, J.C. Tjell, D. McConchie, Increasing the
    arsenate adsorption capacity of neutralized red mud (Bauxsol),
    J. Colloid Interface Sci., 271 (2004) 313–320. 
-  H. Genç-Fuhrman, J.C. Tjell, D. McConchie, Adsorption of
    arsenic from water using activated neutralized red mud,
    Environ. Sci. Technol., 38 (2004) 2428–2434. 
-  T.S. Singh, K.K. Pant, Equilibrium, kinetics and thermodynamic
    studies for adsorption of As(III) on activated alumina, Sep.
    Purif. Technol., 36 (2004) 139–147. 
-  S.R. Kanel, B. Manning, L. Charlet, H. Choi, Removal of
    arsenic(III) from groundwater by nanoscale zero-valent iron,
    Environ. Sci. Technol., 39 (2005) 1291–1298. 
-  S. Maity, S. Chakravarty, S. Bhattacharjee, B. Roy, A study on
    arsenic adsorption on polymetallic sea nodule in aqueous
    medium, J. Water Res., 39 (2005) 2579–2590. 
-  S. Chakravarty, V. Dureja, G. Bhattacharyya, S. Maity,
    S. Bhattacharjee, Removal of arsenic from groundwater using
    low cost ferruginous manganese ore, J. Water Res., 36 (2002)
    625–632. 
-  B.E. Reed, R. Vaughan, L. Jiang, As(III), As(V), Hg, and Pb
    removal by Fe-oxide impregnated activated carbon, 
 J. Environ.
    Eng., 126 (2000) 869–873.
-  T. Budinova, N. Petrov, M. Razvigorova, J. Parra, P. Galiatsatou,
    Removal of arsenic(III) from aqueous solution by activated
    carbons prepared from solvent extracted olive pulp and olive
    stones, Ind. Eng. Chem. Res., 45 (2006) 1896–1901. 
-  D. Mohan, C.U. Pittman Jr., M. Bricka, F. Smith, B. Yancey,
    J. Mohammad, P.H. Steele, M.F. Alexandre-Franco, 
 V. Gómez-Serrano, H. Gong, Sorption of arsenic, cadmium, and lead by
    chars produced from fast pyrolysis of wood and bark during
    bio-oil production, J. Colloid Interface Sci., 310 (2007) 57–73.
-  P.W. Ayers, The physical basis of the hard/soft acid/base
    principle, Faraday Discuss., 135 (2007) 161–190. 
-  R.G. Pearson, Hard and soft acids and bases, J. Am. Chem. Soc.,
    85 (1963) 3533–3539. 
-  R.F. Nalewajski, Electrostatic effects in interactions between
    hard (soft) acids and bases, J. Am. Chem. Soc., 106 (1984)
    944–945. 
-  E. Matijević, L.J. Stryker, Coagulation and reversal of charge
    of lyophobic colloids by hydrolyzed metal ions: III. Aluminum
    sulfate, J. Colloid Interface Sci., 22 (1966) 68–77. 
-  L. Semerjian, G. Ayoub, High-pH–magnesium coagulation–flocculation in wastewater treatment, Adv. Environ. Res.,
    7 (2003) 389–403. 
-  P. Morgan, T.H. Frost, Germicide, United States Patent Office,
    Official Gazzete 1942. 
-  C.C. Mólgora, A.M. Domínguez, E.M. Avila, P. Drogui,
    G. Buelna, Removal of arsenic from drinking water: 
 a
    comparative study between electrocoagulation-microfiltration
    and chemical coagulation-microfiltration processes, Sep. Purif.
    Technol., 118 (2013) 645–651.
-  M. Piñón-Miramontes, R.G. Bautista-Margulis, A.J.F. Pérez-Hernández, Removal of arsenic and fluoride from drinking
    water with cake alum and a polymeric anionic flocculent,
    Fluoride, 36 (2003) 122–128.