Ahmad, M., Rajapaksha, A. U., Lim, J. E., Zhang, M., Bolan, N., Mohan, D., Vithanage, M., Lee, S. S. and Ok, Y. S. (2014). Biochar as a sorbent for contaminant management in soil and water: a review. Chemosphere, 99, 19-33.
 Akpomie, K. G., Dawodu, F. A., Adebowale, K. O. (2015). Mechanism on the sorption of heavy metals from binary-solution by a low cost montmorillonite and its desorption potential. Alexandria engineering journal, 54(3), 757-767.
 Alvarez-Ayuso, E., Garćia-Sánchez, A. (2003). Removal of heavy metals from waste waters by natural and Na-exchanged bentonites. Clays and clay minerals, 51(5), 475-480.
 An, Q., Jiang, Y. Q., Nan, H. Y., Yu, Y., Jiang, J. N. (2019). Unraveling sorption of nickel from aqueous solution by KMnO4 and KOH-modified peanut shell biochar: Implicit mechanism. Chemosphere, 214, 846-854.
 Basha, C. A., Bhadrinarayana, N., Anantharaman, N. and Begum, K. M. S. (2008). Heavy metal removal from copper smelting effluent using electrochemical cylindrical flow reactor. Journal of hazardous materials, 152(1), 71-78.
 Bashir, S., Zhu, J., Fu, Q. and Hu, H. (2018). Comparing the adsorption mechanism of Cd by rice straw pristine and KOH-modified biochar. Environmental science and pollution research, 25(12), 11875-11883.
 Cheng, Q., Huang, Q., Khan, S., Liu, Y., Liao, Z., Li, G. and Ok, Y. S. (2016). Adsorption of Cd by peanut husks and peanut husk biochar from aqueous solutions. Ecological Engineering, 87, 240-245.
 Deng, J., Liu, Y., Liu, S., Zeng, G., Tan, X., Huang, B., Tang, X., Wang, S., Hua, Q. and Yan, Z. (2017). Competitive adsorption of Pb (II), Cd (II) and Cu (II) onto chitosan-pyromellitic dianhydride modified biochar. Journal of colloid and interface science, 506, 355-364.
 Ersahin, M. E., Ozgun, H., Dereli, R. K., Ozturk, I., Roest, K. and van Lier, J. B. (2012). A review on dynamic membrane filtration: materials, applications and future perspectives. Bioresource technology 122, 196-206.
 Fan, S., Li, H., Wang, Y., Wang, Z., Tang, J., Tang, J. and Li, X. (2018). Cadmium removal from aqueous solution by biochar obtained by co-pyrolysis of sewage sludge with tea waste. Research on chemical intermediates, 44(1), 135-154.
 Gerente, C., Lee, V., Cloirec, P. L. and McKay, G. (2007). Application of chitosan for the removal of metals from wastewaters by adsorption mechanisms and models review. Critical reviews in environmental science and technology, 37(1): 41-127.
. Huang, J., Wu, Z., Chen, L. and Sun, Y. (2015). Surface complexation modeling of adsorption of Cd (II) on graphene oxides. Journal of molecular liquids, 209, 753-758.
. Huang, X., Liu, Y., Liu, S., Tan, X., Ding, Y., Zeng, G., Zhou, Y., Zhang, M., Wang, S. and Zheng, B. (2016). Effective removal of Cr (VI) using β-cyclodextrin–chitosan modified biochars with adsorption/reduction bifuctional roles. RSC advances, 6(1), 94-104.
 Inyang, M., Gao, B., Yao, Y., Xue, Y., Zimmerman, A. R., Pullammanappallil, P. and Cao, X. (2012). Removal of heavy metals from aqueous solution by biochars derived from anaerobically digested biomass. Bioresource technology, 110, 50-56.
 Inyang, M. I., Gao, B., Yao, Y., Xue, Y., Zimmerman, A., Mosa, A., Pullammanappallil, P., Ok, Y. S. and Cao, X. (2016). A review of biochar as a low-cost adsorbent for aqueous heavy metal removal. Critical reviews in environmental science and technology, 46(4), 406-433.
 Jung, K. W., Hwang, M. J., Ahn, K. H. and Ok, Y. S. (2015). Kinetic study on phosphate removal from aqueous solution by biochar derived from peanut shell as renewable adsorptive media. International journal of environmental science and technology, 12(10), 3363-3372.
 Kataria, N. and Garg, V. (2018). Green synthesis of Fe3O4 nanoparticles loaded sawdust carbon for cadmium (II) removal from water: Regeneration and mechanism. Chemosphere, 208, 818-828.
 Kim, W. K., Shim, T., Kim, Y. S., Hyun, S., Ryu, C., Park, Y. K. and Jung, J. (2013). Characterization of cadmium removal from aqueous solution by biochar produced from a giant Miscanthus at different pyrolytic temperatures. Bioresource technology, 138, 266-270.
 Laus, R. and De Favere, V. T. (2011). Competitive adsorption of Cu (II) and Cd (II) ions by chitosan crosslinked with epichlorohydrin–triphosphate. Bioresource technology, 102(19), 8769-8776.
 Li, Z., Ma, Z., van der Kuijp, T. J., Yuan, Z. and Huang, L. (2014). A review of soil heavy metal pollution from mines in China: pollution and health risk assessment. Science of the total environment, 468, 843-853.
 Liu, L. and Fan, S. (2018). Removal of cadmium in aqueous solution using wheat straw biochar: effect of minerals and mechanism. Environmental science and pollution research, 25(9), 8688-8700.
 Markandeya, S. and Kisku, G. (2015). Linear and nonlinear kinetic modeling for adsorption of disperse dye in batch process. Research journal of environmental toxicology, 9, 320-331.
 Mohan, D., Kumar, H., Sarswat, A., Alexandre Franco, M. and Pittman Jr, C. U. (2014). Cadmium and lead remediation using magnetic oak wood and oak bark fast pyrolysis bio-chars. Chemical engineering journal, 236, 513-528.
 Moyo, M., Lindiwe, S. T., Sebata, E., Nyamunda, B. C. and Guyo, U. (2016). Equilibrium, kinetic, and thermodynamic studies on biosorption of Cd (II) from aqueous solution by biochar. Research on chemical intermediates, 42(2), 1349-1362.
 Naderi, A., Delavar, M. A., Ghorbani, Y., Kaboudin, B. and Hosseini, M. (2018). Modification of nano-clays with ionic liquids for the removal of Cd (II) ion from aqueous phase. Applied clay science, 158, 236-245.
 Nguyen, T. C., Loganathan, P., Nguyen, T. V., Kandasamy, J., Naidu, R. and Vigneswaran, S. (2018). Adsorptive removal of five heavy metals from water using blast furnace slag and fly ash. Environmental science and pollution research, 25(21), 20430-20438.
 Olabemiwo, F. A., Tawabini, B. S., Patel, F., Oyehan, T. A., Khaled, M. and Laoui, T. (2017). Cadmium Removal from Contaminated Water Using Polyelectrolyte-Coated Industrial Waste Fly Ash. Bioinorganic chemistry and applications, 2017(1), 1-13.
 Owlad, M., Aroua, M. K., Daud, W. A. W. and Baroutian, S. (2009). Removal of hexavalent chromium-contaminated water and wastewater: A review. Water, air, and soil pollution, 200(1-4), 59-77.
 Rathod, V., Pansare, H., Bhalerao, S. A. and Maind, S. D. (2015). Adsorption and Desorption Studies of Cadmium (II) ions from aqueous solutions onto Tur pod (Cajanus cajan). International journal of advanced chemistry research, 4(5), 30-38.
 Ruthiraan, M., Mubarak, N. M., Thines, R. K., Abdullah, E. C., Sahu, J. N., Jayakumar, N. S. and Ganesan, P. (2015). Comparative kinetic study of functionalized carbon nanotubes and magnetic biochar for removal of Cd2+ ions from wastewater. Korean journal of chemical engineering, 32(3), 446-457.
 Salehi, E., Daraei, P. and Shamsabadi, A. A. (2016). A review on chitosan-based adsorptive membranes. Carbohydrate polymers, 152, 419-432.
 Shah, K., Gupta, K. and Sengupta, B. (2017). Selective separation of copper and zinc from spent chloride brass pickle liquors using solvent extraction and metal recovery by precipitation-stripping. Journal of environmental chemical engineering, 5(5), 5260-5269.
 Song, Y., Wang, F., Bian, Y., Kengara, F. O., Jia, M., Xie, Z. and Jiang, X. (2012). Bioavailability assessment of hexachlorobenzene in soil as affected by wheat straw biochar. Journal of hazardous materials, 217, 391-397.
 Sud, D., Mahajan, G. and Kaur, M. (2008). Agricultural waste material as potential adsorbent for sequestering heavy metal ions from aqueous solutions–A review. Bioresource technology, 99(14), 6017-6027.
 Tharanathan, R. N. and Kittur, F. S. (2003). Chitin the undisputed biomolecule of great potential. Critical reviews in food science and nutrition, 43(1), 61-87.
 Thuan, L. V., Chau, T. B., Ngan, T. T. K., Vu, T. X., Nguyen, D. D., Nguyen, M.-H., Thao, D. T. T., To Hoai, N. and Sinh, L. H. (2018). Preparation of cross-linked magnetic chitosan particles from steel slag and shrimp shells for removal of heavy metals. Environmental technology, 39(14), 1745-1752.
 Wang, B., Jiang, Y. s., Li, F. y. and Yang, D. y. (2017). Preparation of biochar by simultaneous carbonization, magnetization and activation for norfloxacin removal in water. Bioresource technology, 233, 159-165.
 Wang, H., Gao, B., Wang, S., Fang, J., Xue, Y. and Yang, K. (2015). Removal of Pb (II), Cu (II), and Cd (II) from aqueous solutions by biochar derived from KMnO4 treated hickory wood. Bioresource technology, 197, 356-362.
 Wongrod, S., Simon, S., van Hullebusch, E. D., Lens, P. N. and Guibaud, G. (2018). Changes of sewage sludge digestate-derived biochar properties after chemical treatments and influence on As (III and V) and Cd (II) sorption. International biodeterioration and biodegradation, 135, 96-102.
 Xiang, J., Lin, Q., Cheng, S., Guo, J., Yao, X., Liu, Q., Yin, G. and Liu, D. (2018). Enhanced adsorption of Cd(II) from aqueous solution by a magnesium oxide–rice husk biochar composite. Environmental science and pollution research, 25(14), 14032-14042.
 Yang, G.-X. and Jiang, H. (2014). Amino modification of biochar for enhanced adsorption of copper ions from synthetic wastewater. Water research. 48, 396-405.
 Yang, J., Ma, T., Li, X., Tu, J., Dang, Z., Yang, C. (2018). Removal of heavy metals and metalloids by amino‐modified biochar supporting nanoscale zero‐valent Iron. Journal of environmental quality, 47(5), 1196-1204.
 Yu, J., Zhu, Z., Zhang, H., Qiu, Y. and Yin, D. (2018). Mg–Fe layered double hydroxide assembled on biochar derived from rice husk ash: facile synthesis and application in efficient removal of heavy metals. Environmental science and pollution research, 25(24), 24293-24304.
 Yu, S., Zhai, L., Wang, Y., Liu, X., Xu, L. and Cheng, L. (2015). Synthesis of magnetic chrysotile nanotubes for adsorption of Pb (II), Cd (II) and Cr (III) ions from aqueous solution. Journal of environmental chemical engineering, 3(2), 752-762.
 Yuan, J.-H., Xu, R.-K. and Zhang, H. (2011). The forms of alkalis in the biochar produced from crop residues at different temperatures. Bioresource technology, 102(3), 3488-3497.
 Zhou, X., Zhou, J., Liu, Y., Guo, J., Ren, J. and Zhou, F. (2018). Preparation of iminodiacetic acid-modified magnetic biochar by carbonization, magnetization and functional modification for Cd (II) removal in water. Fuel, 233,469-479.
 Zhou, Y., Gao, B., Zimmerman, A. R., Fang, J., Sun, Y. and Cao, X. (2013). Sorption of heavy metals on chitosan-modified biochars and its biological effects. Chemical engineering journal, 231, 512-518.