1. M.L. Gao, Y. Zhang, X.L. Gong, Z.G. Song, Z.Y. Guo, Removal mechanism of di-n-butyl phthalate and oxytetracycline from aqueous solutions by nano-manganese dioxide modified biochar, Environ. Sci. Pollut. Res., 25 (2018) 7796–7807.
  2. J.H. Franco, B.F. da Silva, E.F.G. Dias, A.A. de Castro, T.C. Ramalho, M.V.B, Zanoni, Influence of auxochrome group in disperse dyes bearing azo groups as chromophore center in the biotransformation and molecular docking prediction by reductase enzyme: implications and assessment for environmental toxicity of xenobiotics, Ecotoxicol. Environ. Saf., 160 (2018) 114–126.
  3. Z.J. Huang, Z.Y. Huang, L.J. Feng, X.W. Luo, P.X. Wu, L.H. Cui, X.Y. Mao, Modified cellulose by polyethyleneimine and ethylenediamine with induced Cu(II) and Pb(II) adsorption potentialities, Carbohydr. Polym., 202 (2018) 470–478.
  4. Lalita, A.P. Singh, R.K. Sharma, Synthesis and characterization of graft copolymers of chitosan with NIPAM and binary monomers for removal of Cr(VI), Cu(II) and Fe(II) metal ions from aqueous solutions, Int. J. Biol. Macromol., 99 (2017) 409–426.
  5. R.L. Gao, Q.L. Fu, H.Q. Hu, Q. Wang, Y.H. Liu, J. Zhu, Highlyeffective removal of Pb by co-pyrolysis biochar derived from rape straw and orthophosphate, J. Hazard. Mater., 371 (2019) 191–197.
  6. D.L. Huang, C.J. Hu, G.M. Zeng, M. Cheng, P. Xu, X.M. Gong, R.Z. Wang, W.J. Xue, Combination of Fenton processes and biotreatment for wastewater treatment and soil remediation, Sci. Total Environ., 574 (2017) 1599–1610.
  7. A.I.A. Sherlala, A.A.A. Raman, M.M. Bello, A. Asghar, A review of the applications of organo-functionalized magnetic graphene oxide nanocomposites for heavy metal adsorption, Chemosphere, 193 (2018) 1004–1017.
  8. J. Barton, M.B.G. García, D.H. Santos, P. Fanjul-Bolado, A. Ribotti, M. McCaul, D. Diamond, P. Magni, Screen-printed electrodes for environmental monitoring of heavy metal ions: a review, Microchim. Acta, 183 (2016) 503–517.
  9. D.L. Huang, R. Deng, J. Wan, G.M. Zeng, W.J. Xue, X.F. Wen, C.Y. Zhou, L. Hu, X.G. Liu, P. Xu, X.Y. Guo, X.Y. Ren, Remediation of lead-contaminated sediment by biocharsupported nano-chlorapatite: accompanied with the change of available phosphorus and organic matters, J. Hazard. Mater., 348 (2018) 109–116.
  10. J. Ma, Y. Ma, F. Yu, X.H. Dai, Rotating magnetic field-assisted adsorption mechanism of pollutants on mechanically strong sodium alginate/graphene/l-cysteine beads in batch and fixed-bed column systems, Environ. Sci. Technol., 52 (2018) 13925–13934.
  11. C.Q. Wang, H. Wang, Pb(II) sorption from aqueous solution by novel biochar loaded with nano-particles, Chemosphere, 192 (2018) 1–4.
  12. W.J. Xue, Z.W. Peng, D.L. Huang, G.M. Zeng, J. Wan, R. Xu, M. Cheng, C. Zhang, D.N. Jiang, Z.X. Hu, Nanoremediation of cadmium contaminated river sediments: microbial response and organic carbon changes, J. Hazard. Mater., 359 (2018) 290–299.
  13. S.L. Cardoso, C.S.D. Costa, E. Nishikawa, M.G.C. da Silva, M.G.A. Vieira, Biosorption of toxic metals using the alginate extraction residue from the brown algae Sargassum filipendula as a natural ion-exchanger, J. Cleaner Prod., 165 (2017) 491–499.
  14. R. Deng, D.L. Huang, J. Wan, W.J. Xue, L. Lei, X.F. Wen, X.G. Liu, S. Chen, Y. Yang, Z.H. Li, B. Li, Chloro-phosphate impregnated biochar prepared by co-precipitation for the lead, cadmium and copper synergic scavenging from aqueous solution, Bioresour. Technol., 293 (2019) 122102.
  15. C. Lin, W.J. Luo, T.T. Luo, Q. Zhou, H.F. Li, L.R. Jing, A study on adsorption of Cr(VI) by modified rice straw: characteristics, performances and mechanism, J. Cleaner Prod., 196 (2018) 626–634.
  16. L.E. Hernández-Hernández, A. Bonilla-Petriciolet, D.I. Mendoza-Castillo, H.E. Reynel-Ávila, Antagonistic binary adsorption of heavy metals using stratified bone char columns, J. Mol. Liq., 241 (2017) 334–346.
  17. W. Yao, J. Wang, P.Y. Wang, X.X. Wang, S.J. Yu, Y.D. Zou, J. Hou, T. Hayat, A. Alsaedi, X.K. Wang, Synergistic coagulation of GO and secondary adsorption of heavy metal ions on Ca/Al layered double hydroxides, Environ. Pollut., 229 (2017) 827–836.
  18. O. Tavakoli, V. Goodarzi, M.R. Saeb, N.M. Mahmoodi, R. Borja, Competitive removal of heavy metal ions from squid oil under isothermal condition by CR11 chelate ion exchanger, J. Hazard. Mater., 334 (2017) 256–266.
  19. Y.P. Li, Z.J. Xu, S.Y. Liu, J.W. Zhang, X.N. Yang, Molecular simulation of reverse osmosis for heavy metal ions using functionalized nanoporous graphenes, Comput. Mater. Sci., 139 (2017) 65–74.
  20. S.H. Lee, Y.G. Jeong, Y.I. Yoon, W.H. Park, Hydrolysis of oxidized polyacrylonitrile nanofibrous webs and selective adsorption of harmful heavy metal ions, Polym. Degrad. Stab., 143 (2017) 207–213.
  21. X.M. Gong, D.L. Huang, Y.G. Liu, Z.W. Peng, G.M. Zeng, P. Xu, M. Cheng, R.Z. Wang, J. Wan, Remediation of contaminated soils by biotechnology with nanomaterials: bio-behavior, applications, and perspectives, Crit. Rev. Biotechnol., 38 (2018) 455–468.
  22. G.A. Adebisi, Z.Z. Chowdhury, P.A. Alaba, Equilibrium, kinetic, and thermodynamic studies of lead ion and zinc ion adsorption from aqueous solution onto activated carbon prepared from palm oil mill effluent, J. Cleaner Prod., 148 (2017) 958–968.
  23. D. Xia, F. Tan, C.P. Zhang, X.L. Jiang, Z. Chen, H. Li, Y.M. Zheng, Q.B. Li, Y.P. Wang, ZnCl2-activated biochar from biogas residue facilitates aqueous As(III) removal, Appl. Surf. Sci., 377 (2016) 361–369.
  24. H.T. Hao, G.F. Liu, Y.L. Wang, B.Y. Shi, K. Han, Y. Zhuang, Y. Kong, Simultaneous cationic Cu(II)‒anionic Sb(III) removal by NH2-Fe3O4-NTA core-shell magnetic nanoparticle sorbents synthesized via a facile one-pot approach, J. Hazard. Mater., 362 (2019) 246–257.
  25. J.W. Pan, B.Y. Gao, W. Song, X. Xu, B. Jin, Q.Y. Yue, Column adsorption and regeneration study of magnetic biopolymer resin for perchlorate removal in presence of nitrate and phosphate, J. Cleaner Prod., 213 (2019) 762–775.
  26. H.B. Li, X.L. Dong, E.B. da Silva, L.M. de Oliveira, Y.S. Chen, L.Q. Ma, Mechanisms of metal sorption by biochars: biochar characteristics and modifications, Chemosphere, 178 (2017) 466–478.
  27. W.J. Xue, D.L. Huang, G.M. Zeng, J. Wan, C. Zhang, R. Xu, M. Cheng, R. Deng, Nanoscale zero-valent iron coated with rhamnolipid as an effective stabilizer for immobilization of Cd and Pb in river sediments, J. Hazard. Mater., 341 (2018) 381–389.
  28. A. Maleki, Z. Hajizadeh, V. Sharifi, Z. Emdadi, A green, porous and eco-friendly magnetic geopolymer adsorbent for heavy metals removal from aqueous solutions, J. Cleaner Prod., 215 (2019) 1233–1245.
  29. Q.Q. Yin, R.K. Wang, Z.H. Zhao, Application of Mg–Al-modified biochar for simultaneous removal of ammonium, nitrate, and phosphate from eutrophic water, J. Cleaner Prod., 176 (2018) 230–240.
  30. M. Fomina, G.M. Gadd, Biosorption: current perspectives on concept, definition and application, Bioresour. Technol., 160 (2014) 3–14.
  31. J.S. He, J.P. Chen, A comprehensive review on biosorption of heavy metals by algal biomass: materials, performances, chemistry, and modeling simulation tools, Bioresour. Technol., 160 (2014) 67–78.
  32. S.H.A. Hassan, M. Koutb, N.A. Nafady, E.A. Hassan, Potentiality of Neopestalotiopsis clavispora ASU1 in biosorption of cadmium and zinc, Chemosphere, 202 (2018) 750–756.
  33. B.-Y. Chen, C.-Y. Chen, W.-Q. Guo, H.-W. Chang, W.-M. Chen, D.-J. Lee, C.-C. Huang, N.-Q. Ren, J.-S. Chang, Fixed-bed biosorption of cadmium using immobilized Scenedesmus obliquus CNW-N cells on loofa (Luffa cylindrica) sponge, Bioresour. Technol., 160 (2014) 175–181.
  34. S. Ozturk, B. Aslim, Z. Suludere, Cadmium(II) sequestration characteristics by two isolates of Synechocystis sp. in terms of exopolysaccharide (EPS) production and monomer composition, Bioresour. Technol., 101 (2010) 9742–9748.
  35. H.C. Xu, H.Y. Cai, G.H. Yu, H.L. Jiang, Insights into extracellular polymeric substances of cyanobacterium Microcystis aeruginosa using fractionation procedure and parallel factor analysis, Water Res., 47 (2013) 2005–2014.
  36. Z.H. Wei, R.E. Xing, X. Zhang, S. Liu, H.H. Yu, P.C. Li, Facile template-free fabrication of hollow nest-like α-Fe2O3 nanostructures for water treatment, ACS Appl. Mater. Interfaces, 5 (2012) 598–604.
  37. X.L. Gou, G.X. Wang, X.Y. Kong, D. Wexler, J. Horvat, J. Yang, J. Park, Flutelike porous hematite nanorods and branched nanostructures: synthesis, characterisation and application for gas-sensing, Chem. Eur. J., 14 (2010) 5996–6002.
  38. E. Repo, J.K. Warchoł, A. Bhatnagar, M.Sillanpää, Heavy metals adsorption by novel EDTA-modified chitosan–silica hybrid materials, J. Colloid Interface Sci., 358 (2011) 261–267.
  39. Z. Bacsik, N. Ahlsten, A. Ziadi, G.Y. Zhao, A. Garcia, B. Martin- Matute, N. Hedin, Mechanisms and kinetics for sorption of CO2 on bicontinuous mesoporous silica modified with n-propylamine, Langmuir, 27 (2011) 11118–11128.
  40. Y. Gutha, V.S. Munagapati, Removal of Pb(II) ions by using magnetic chitosan-4-((pyridin-2-ylimino)methyl) benzaldehyde Schiff’s base, Int. J. Biol. Macromol., 93 (2016) 408–417.
  41. N. Zhang, G.-L. Zang, C. Shi, H.-Q. Yu, G.-P. Sheng, A novel adsorbent TEMPO-mediated oxidized cellulose nanofibrils modified with PEI: preparation, characterization, and application for Cu(II) removal, J. Hazard. Mater., 316 (2016) 11–18.
  42. X.Q. Lu, A.M. Vassallo, W.D. Johnson, Thermal stability of humic substances and their metal forms: an investigation using FTIR emission spectroscopy, J. Anal. Appl. Pyrolysis, 43 (1997) 103–113.
  43. X.M. Ren, D.D. Shao, S.T. Yang, J. Hu, G.D. Sheng, X.L. Tan, X.K. Wang, Comparative study of Pb(II) sorption on XC-72 carbon and multi-walled carbon nanotubes from aqueous solutions, Chem. Eng. J., 170 (2011) 170–177.
  44. M. Bansal, U. Garg, D. Singh, V.K. Garg, Removal of Cr(VI) from aqueous solutions using pre-consumer processing agricultural waste: a case study of rice husk, J. Hazard. Mater., 162 (2009) 312–320.
  45. L.S. Tan, J. Xu, X.Q. Xue, Z.M. Lou, J. Zhu, S. Baig, X.H. Xu, Multifunctional nanocomposite Fe3O4@SiO2-mPD/SP for selective removal of Pb(II) and Cr(VI) from aqueous solutions, RSC Adv., 4 (2014) 45920–45929.
  46. Q.M. Li, H.O. Song, R.M. Han, G.X. Wang, A.M. Li, Efficient removal of Cu(II) and citrate complexes by combined permanent magnetic resin and its mechanistic insights, Chem. Eng. J., 366 (2019) 1–10.
  47. Y.D. Zou, X.X. Wang, A. Khan, P.Y. Wang, Y.-H. Liu, A. Alsaedi, T. Hayat, X.K. Wang, Environmental remediation and application of nanoscale zero-valent iron and its composites for the removal of heavy metal ions: a review, Environ. Sci. Technol., 50 (2016) 7290–7304.
  48. Y.M. Ren, N. Li, J. Feng, T.Z. Luan, Q. Wen, Z.S. Li, M.L. Zhang, Adsorption of Pb(II) and Cu(II) from aqueous solution on magnetic porous ferrospinel MnFe2O4, J. Colloid Interface Sci., 367 (2012) 415–421.
  49. X.Y. Guo, B. Du, Q. Wei, J. Yang, L.H. Hu, L.G. Yan, W.Y. Xu, Synthesis of amino functionalized magnetic graphenes composite material and its application to remove Cr(VI), Pb(II), Hg(II), Cd(II) and Ni(II) from contaminated water, J. Hazard. Mater., 278 (2014) 211–220.
  50. L. Sun, H.W. Yu, B. Fugetsu, Graphene oxide adsorption enhanced by in situ reduction with sodium hydrosulfite to remove acridine orange from aqueous solution, J. Hazard. Mater., 203–204 (2012) 101–110.
  51. W.S. Wan Ngah, C.S. Endud, R. Mayanar, Removal of copper(II) ions from aqueous solution onto chitosan and cross-linked chitosan beads, React. Funct. Polym., 50 (2002) 181–190.
  52. L. Zhou, Y.G. Liu, S.B. Liu, Y.C. Yin, G.M. Zeng, X.F. Tan, X. Hu, X.J. Hu, L.H. Jiang, Y. Ding, S.H. Liu, X.X. Huang, Investigation of the adsorption-reduction mechanisms of hexavalent chromium by ramie biochars of different pyrolytic temperatures, Bioresour. Technol., 218 (2016) 351–359.
  53. A. Baran, E. Bıçak, Ş.H. Baysal, S. Önal, Comparative studies on the adsorption of Cr(VI) ions on to various sorbents, Bioresour. Technol., 98 (2007) 661–665.
  54. D.K. Li, Q. Li, D.Y. Mao, N.N. Bai, H.Z. Dong, A versatile biobased material for efficiently removing toxic dyes, heavy metal ions and emulsified oil droplets from water simultaneously, Bioresour. Technol., 245 (2017) 649–655.
  55. M. Naushad, T. Ahamad, B.M. Al-Maswari, A. Abdullah Alqadami, S.M. Alshehri, Nickel ferrite bearing nitrogen-doped mesoporous carbon as efficient adsorbent for the removal of highly toxic metal ion from aqueous medium, Chem. Eng. J., 330 (2017) 1351–1360.
  56. D.K. Singh, V. Kumar, S. Mohan, S.H. Hasan, Polylysine functionalized graphene aerogel for the enhanced removal of Cr(VI) through adsorption: kinetic, isotherm, and thermodynamic modeling of the process, J. Chem. Eng. Data, 62 (2017) 1732–1742.
  57. Z.Y. Li, J.Y. Chen, Y.Y. Ge, Removal of lead ion and oil droplet from aqueous solution by lignin-grafted carbon nanotubes, Chem. Eng. J., 308 (2017) 809–817.
  58. F.H. Frimmel, L. Huber, Influence of humic substances on the aquatic adsorption of heavy metals on defined mineral phases, Environ. Int., 22 (1996) 507–517.
  59. G. McKay, M.S. Otterburn, A.G. Sweeney, The removal of colour from effluent using various adsorbents—III. Silica: rate processes, Water Res., 14 (1980) 15–20.
  60. L.-S. Zhong, J.-S. Hu, H.-P. Liang, A.-M. Cao, W.-G. Song, L.-J. Wan, Self-assembled 3D flowerlike iron oxide nanostructures and their application in water treatment, Adv. Mater., 18 (2006) 2426–2431.
  61. A. Mahapatra, B.G. Mishra, G. Hota, Electrospun Fe2O3–Al2O3 nanocomposite fibers as efficient adsorbent for removal of heavy metal ions from aqueous solution, J. Hazard. Mater., 258–259 (2013) 116–123.
  62. Z.W. Wang, X.F. Zeng, X.M. Yu, H. Zhang, Z.J. Li, D. Jin, Adsorption behaviors of Cd2+ on Fe2O3/MnO2 and the effects of coexisting ions under alkaline conditions, Chin. J. Geochem., 29 (2010) 197–203.
  63. X.L. Zhang, Q.L. Zhang, L.Q. Zhang, T. Zhang, L.Y. Hu, Particle concentration effect of Cr(VI) adsorption by Bentonite load FeOOH, Pollut. Control Technol., 26 (2013) 28–32.
  64. R. Tongyan, Study on adsorbability of Cu2+ by α-FeOOH nanowires, Guangdong Chem. Ind., 20 (2016) 49–50.
  65. W. Xu, H.C. Lan, H.J. Wang, H.M. Liu, J.H. Qu, Comparing the adsorption behaviors of Cd, Cu and Pb from water onto Fe-Mn binary oxide, MnO2 and FeOOH, Front. Environ. Sci. Eng., 9 (2015) 385–393.
  66. H.W. Liu, Z.Q. Lu, H.Y. Zhang, Y.H. Chen, Y. Zhou, Adsorption performance of Aldoped α-FeOOH nanoparticles to Pb2+, Inorg. Chem. Ind., 43 (2011) 16–18.
  67. Y.-Y. Deng, X.-F. Xiao, D. Wang, B. Han, Y. Gao, J.-L. Xue, Adsorption of Cr(VI) from aqueous solution by ethylenediaminetetraacetic acid-chitosan-modified metal-organic framework, J. Nanosci. Nanotechnol., 20 (2020) 1660–1669.
  68. Z.A. Al-Othman, R. Ali, M. Naushad, Hexavalent chromium removal from aqueous medium by activated carbon prepared from peanut shell: adsorption kinetics, equilibrium and thermodynamic studies, Chem. Eng. J., 184 (2012) 238–247.
  69. L.G. Zhang, J.S. Pan, L. Liu, K. Song, Q.L. Wang, Combined physical and chemical activation of sludge-based adsorbent enhances Cr(VI) removal from wastewater, J. Cleaner Prod., 238 (2019) 117904.
  70. Y.N. Zhu, H. Zhang, H. Zeng, M. Liang, R. Lu, Adsorption of chromium(VI) from aqueous solution by the iron(III)-impregnated sorbent prepared from sugarcane bagasse, Int. J. Environ. Sci. Technol., 9 (2012) 463–472.
  71. S.R. Chowdhury, E.K. Yanful, A.R. Pratt, Chemical states in XPS and Raman analysis during removal of Cr(VI) from contaminated water by mixed maghemite–magnetite nanoparticles, J. Hazard. Mater., 235–236 (2012) 246–256.
  72. S.-J. Lee, J.H. Park, Y.-T. Ahn, J.W. Chung, Comparison of heavy metal adsorption by peat moss and peat moss-derived biochar produced under different carbonization conditions, Water Air Soil Pollut., 226 (2015) 1–11.
  73. Y. Ren, H.A. Abbood, F.B. He, H. Peng, K.X. Huang, Magnetic EDTA-modified chitosan/SiO2/Fe3O4 adsorbent: preparation, characterization, and application in heavy metal adsorption, Chem. Eng. J., 226 (2013) 300–311.
  74. N.A. Dahlan, A.K. Veeramachineni, S.J. Langford, J. Pushpamalar, Developing of a magnetite film of carboxymethyl cellulose grafted carboxymethyl polyvinyl alcohol (CMC-g-CMPVA) for copper removal, Carbohydr. Polym., 173 (2017) 619–630.
  75. S.Y. Chen, Y. Zou, Z.Y. Yan, W. Shen, S.K. Shi, X. Zhang, H.P. Wang, Carboxymethylated-bacterial cellulose for copper and lead ion removal, J. Hazard. Mater., 161 (2009) 1355–1359.
  76. A.A. Yakout, R.H. El-Sokkary, M.A. Shreadah, O.G. Abdel Hamid, Cross-linked graphene oxide sheets via modified extracted cellulose with high metal adsorption, Carbohydr. Polym., 172 (2017) 20–27.
  77. S.-F. Lo, S.-Y. Wang, M.-J. Tsai, L.-D. Lin, Adsorption capacity and removal efficiency of heavy metal ions by Moso and Ma bamboo activated carbons, Chem. Eng. Res. Des., 90 (2012) 1397–1406.
  78. N. Li, R.B. Bai, Copper adsorption on chitosan–cellulose hydrogel beads: behaviors and mechanisms, Sep. Purif. Technol., 42 (2005) 237–247.
  79. A.-H. Chen, S.-C. Liu, C.-Y. Chen, C.-Y. Chen, Comparative adsorption of Cu(II), Zn(II), and Pb(II) ions in aqueous solution on the crosslinked chitosan with epichlorohydrin, J. Hazard. Mater., 154 (2008) 184–191.
  80. A. Duran, M. Soylak, S.A. Tuncel, Poly(vinyl pyridine-poly ethylene glycol methacrylate-ethylene glycol dimethacrylate) beads for heavy metal removal, J. Hazard. Mater., 155 (2008) 114–120.
  81. M.-W. Wan, C.-C. Kan, B.D. Rogel, M.L.P. Dalida, Adsorption of copper (II) and lead (II) ions from aqueous solution on chitosancoated sand, Carbohydr. Polym., 80 (2010) 891–899.
  82. Y.-C. Chang, D.-H. Chen, Preparation of absorption properties of monodisperse chitosan-bound Fe3O4 magnetic nanoparticles for removal of Cu(II) ions, J. Colloid Interface Sci., 283 (2005) 446–451.
  83. L.-C. Zhou, Y.-F. Li, X. Bai, G.-H. Zhao, Use of microorganisms immobilized on composite polyurethane foam to remove Cu(II) from aqueous solution, J. Hazard. Mater., 167 (2009) 1106–1113.
  84. Y.W. Chen, J.L. Wang, Preparation and characterization of magnetic chitosan nanoparticles and its application for Cu(II) removal, Chem. Eng. J., 168 (2011) 286–292.
  85. L.P. Ivanova, A.K. Detcheva, P.S. Vassileva, Characterization of two Bulgarian herbs for use as biosorbents for copper(II), Anal. Lett., 52 (2019) 2650–2662.
  86. L. Liu, X.P. Guo, S.Q. Wang, L. Li, Y. Zeng, G.H. Liu, Effects of wood vinegar on properties and mechanism of heavy metal competitive adsorption on secondary fermentation based composts, Ecotoxicol. Environ. Saf., 150 (2018) 270–279.
  87. Y.H. Zhu, J. Hu, J.L. Wang, Competitive adsorption of Pb(II), Cu(II) and Zn(II) onto xanthate-modified magnetic chitosan, J. Hazard. Mater., 221–222 (2012) 155–161.
  88. L.L. Qin, L.G. Yan, J. Chen, T.T. Liu, H.Q. Yu, B. Du, Enhanced removal of Pb2+, Cu2+, and Cd2+ by amino-functionalized magnetite/kaolin clay, Ind. Eng. Chem. Res., 55 (2016) 7344–7354.
  89. T.C. Nguyen, P. Loganathan, T.V. Nguyen, S. Vigneswaran, J. Kandasamy, R. Naidu, Simultaneous adsorption of Cd, Cr, Cu, Pb, and Zn by an iron-coated Australian zeolite in batch and fixed-bed column studies, Chem. Eng. J., 270 (2015) 393–404.
  90. G.-X. Yang, H. Jiang, Amino modification of biochar for enhanced adsorption of copper ions from synthetic wastewater, Water Res., 48 (2014) 396–405.
  91. E. Pehlivan, T. Altun, S. Parlayıcı, Utilization of barley straws as biosorbents for Cu2+ and Pb2+ ions, J. Hazard. Mater., 164 (2009) 982–986.
  92. Q.G. Feng, Q.Y. Lin, F.Z. Gong, S. Sugita, M. Shoya, Adsorption of lead and mercury by rice husk ash, J. Colloid Interface Sci., 278 (2004) 1–8.
  93. T. Depci, A.R. Kul, Y. Önal, Competitive adsorption of lead and zinc from aqueous solution on activated carbon prepared from Van apple pulp: study in single- and multi-solute systems, Chem. Eng. J., 200–202 (2012) 224–236.
  94. M. Momčilović, M. Purenović, A. Bojić, A. Zarubica, M. Ranđelović, Removal of lead(II) ions from aqueous solutions by adsorption onto pine cone activated carbon, Desalination, 276 (2011) 53–59.
  95. M. Naushad, Surfactant assisted nano-composite cation exchanger: development, characterization and applications for the removal of toxic Pb2+ from aqueous medium, Chem. Eng. J., 235 (2014) 100–108.
  96. A. Mittal, M. Naushad, G. Sharma, Z.A. Alothman, S.M. Wabaidur, M. Alam, Fabrication of MWCNTs/ThO2 nanocomposite and its adsorption behavior for the removal of Pb(II) metal from aqueous medium, Desal. Water. Treat., 57 (2016) 21863–21869.
  97. M. Ghasemi, M. Naushad, N. Ghasemi, Y. Khosravi-fard, Adsorption of Pb(II) from aqueous solution using new adsorbents prepared from agricultural waste: adsorption isotherm and kinetic studies, J. Ind. Eng. Chem., 20 (2014) 2193–2199.
  98. Z.X. Li, Z.H. Wang, C.T. Wang, S.L. Ding, F.W. Li, H.F. Lin, Preparation of magnetic resin microspheres M-P(MMA-DVBGMA) and the adsorption property to heavy metal ions, Appl. Surf. Sci., 496 (2019) 143708.
  99. K.A. Krishnan, A. Sheela, T.S. Anirudhan, Kinetic and equilibrium modeling of liquid-phase adsorption of lead and lead chelates on activated carbons, J. Chem. Technol. Biotechnol., 78 (2003) 642–653.
  100. R. Karthik, S. Meenakshi, Removal of Pb(II) and Cd(II) ions from aqueous solution using polyaniline grafted chitosan, Chem. Eng. J., 263 (2015) 168–177.
  101. D. Zhang, P. Yu, X. He, Preparation and characterization of porous calcium titanate-based coated glass fiber filter material and its application in determination of lead and cadmium ion concentrations in water, J. AOAC Int., 94 (2011) 1925–1933.
  102. D. Zhang, C.-L. Zhang, P. Zhou, Preparation of porous nanocalcium titanate microspheres and its adsorption behavior for heavy metal ion in water, J. Hazard. Mater., 186 (2011) 971–977.
  103. D. Zhang, P. Hou, Preparation of nano-calcium titanate powder and its adsorption behavior for lead ion and cadmium ion in water, Acta Chim. Sinica, 67 (2009) 1336–1342.
  104. Ł. Klapiszewski, K. Siwińska-Stefańska, D. Kołodyńska, Development of lignin based multifunctional hybrid materials for Cu(II) and Cd(II) removal from the aqueous system, Chem. Eng. J., 330 (2017) 518–530.
  105. J.X. Xiang, Q.T. Lin, S.L. Cheng, J.L. Guo, X.S. Yao, Q.J. Liu, G.C. Yin, D.F. Liu, Enhanced adsorption of Cd(II) from aqueous solution by a magnesium oxide–rice husk biochar composite, Environ. Sci. Pollut. Res., 25 (2018) 14032–14042.
  106. F.Y. Wang, W.W. Yang, P. Cheng, S.Q. Zhang, S.W. Zhang, W.T. Jiao, Y.H. Sun, Adsorption characteristics of cadmium onto microplastics from aqueous solutions, Chemosphere, 235 (2019) 1073–1080.
  107. R.H. Chang, S.P. Sohi, F.Q. Jing, Y.Y. Liu, J.W. Chen, A comparative study on biochar properties and Cd adsorption behavior under effects of ageing processes of leaching, acidification and oxidation, Environ. Pollut., 254 (2019) 113123.
  108. M. Aghaei, A.H. Kianfar, M. Dinari, Green synthesis of nanostructure Schiff base complex based on aromatic polyamide and manganese(III) for elimination of Hg(II) and Cd(II) from solutions, J. Chem. Soc., 16 (2019) 2489–2500.
  109. J.H. Guo, C.Z. Yan, Z.X. Luo, H.D. Fang, S.G. Hu, Y.L. Cao, Synthesis of a novel ternary HA/Fe-Mn oxides-loaded biochar composite and its application in cadmium(II) and arsenic(V) adsorption, J. Environ. Sci., 85 (2019) 168–176.
  110. B. Wang, H.B. Wu, L. Yu, R. Xu, L. Teik-Thye, X.W.(D). Lou, Template-free formation of uniform urchin-like α-FeOOH hollow spheres with superior capability for water treatment, Adv. Mater., 24 (2012) 1111–1116.
  111. Y. Shen, H. Li, W.Z. Zhu, S.-H. Ho, W.Q. Yuan, J.F. Chen, Y.P. Xie, Microalgal-biochar immobilized complex: a novel efficient biosorbent for cadmium removal from aqueous solution, Bioresour. Technol., 244 (2017) 1031–1038.
  112. J.K. Bediako, W. Wei, S. Kim, Y.-S. Yun, Removal of heavy metals from aqueous phases using chemically modified waste Lyocell fiber, J. Hazard. Mater., 299 (2015) 550–561.
  113. Z.L. Du, T. Zheng, P. Wang, L.L. Hao, Y.X. Wang, Fast microwave-assisted preparation of a low-cost and recyclable carboxyl modified lignocellulose-biomass jute fiber for enhanced heavy metal removal from water, Bioresour. Technol., 201 (2016) 41–49.
  114. H.J. Dai, Y. Huang, H.H. Huang, Eco-friendly polyvinyl alcohol/carboxymethyl cellulose hydrogels reinforced with graphene oxide and bentonite for enhanced adsorption of methylene blue, Carbohydr. Polym., 185 (2018) 1–11.
  115. Y.K. Long, L. Xiao, Q.H. Cao, Co-polymerization of catechol and polyethylenimine on magnetic nanoparticles for efficient selective removal of anionic dyes from water, Powder Technol., 310 (2017) 24–34.