Mehrabi, N., Soleimani, M., Yeganeh, M. M., Sharififard, H. (2015). Parameter optimization for nitrate removal from water using activated carbon and composite of activated carbon and Fe2O3 nanoparticles. RSC Advances,5(64), 51470-51482.
 Sharififard, H., Soleimani, M. (2015). Performance comparison of activated carbon and ferric oxide-hydroxide–activated carbon nanocomposite as vanadium (V) ion adsorbents. RSC Advances,5(98), 80650-80660
 Bergaoui, M., Nakhli, A., Benguerba, Y., Khalfaoui, M., Erto, A., Soetaredjo, F. E Ernst, B. (2018). Novel insights into the adsorption mechanism of methylene blue onto organo-bentonite: Adsorption isotherms modeling and molecular simulation. Journal of molecular liquids,272, 697-707.
 Hwang, J., Joss, L., Pini, R. (2019). Measuring and modelling supercritical adsorption of CO2 and CH4 on montmorillonite source clay. Microporous and Mesoporous Materials,73, 107-121.
 Salam, M. A., Kosa, S. A., Al-Beladi, A. A. (2017). Application of nanoclay for the adsorptive removal of Orange G dye from aqueous solution. Journal of molecular liquids,241, 469-477.
 Almasri, D. A., Rhadfi, T., Atieh, M. A., McKay, G., Ahzi, S. (2018). High performance hydroxyiron modified montmorillonite nanoclay adsorbent for arsenite removal. Chemical engineering journal,335, 1-12.
 Mishra, A., Mehta, A., Sharma, M., Basu, S. (2017). Enhanced heterogeneous photodegradation of VOC and dye using microwave synthesized TiO2/Clay nanocomposites: A comparison study of different type of clays. Journal of alloys and compounds,694, 574-580.
 Mishra, A., Mehta, A., Kainth, S., Basu, S. (2018). Effect of different plasmonic metals on photocatalytic degradation of volatile organic compounds (VOCs) by bentonite/M-TiO2 nanocomposites under UV/visible light. Applied clay science,153, 144-153.
 Razzaz, A., Ghorban, S., Hosayni, L., Irani, M., Aliabadi, M. (2016). Chitosan nanofibers functionalized by TiO2 nanoparticles for the removal of heavy metal ions. Journal of the Taiwan institute of chemical engineers,58, 333-343.
 Ismail, A. A., El-Midany, A. A., Ibrahim, I. A., Matsunaga, H. (2008). Heavy metal removal using SiO2-TiO2 binary oxide: experimental design approach. Adsorption, 14(1), 21-29.
 Lee, Y. C., Yang, J. W. (2012). Self-assembled flower-like TiO2 on exfoliated graphite oxide for heavy metal removal. Journal of industrial and engineering chemistry,18(3), 1178-1185.
 Bouazizi, A., Breida, M., Achiou, B., Ouammou, M., Calvo, J. I., Aaddane, A., Younssi, S. A. (2017). Removal of dyes by a new nano–TiO2 ultrafiltration membrane deposited on low-cost support prepared from natural Moroccan bentonite. Applied clay science,149, 127-135.
 Nwankwo, U., Bucher, R., Ekwealor, A. B. C., Khamlich, S., Maaza, M., Ezema, F. I. (2019). Synthesis and characterizations of rutile-TiO2 nanoparticles derived from chitin for potential photocatalytic applications. Vacuum,161, 49-54.
 MiarAlipour, S., Friedmann, D., Scott, J., Amal, R. (2018). TiO2/porous adsorbents: Recent advances and novel applications. Journal of hazardous materials,341, 404-423.
 Yin, X., Meng, X., Zhang, Y., Zhang, W., Sun, H., Lessl, J. T., Wang, N. (2018). Removal of V (V) and Pb (II) by nanosized TiO2 and ZnO from aqueous solution. Ecotoxicology and environmental safety, 164, 510-519.
 Sharma, M., Singh, J., Hazra, S., Basu, S. (2019). Adsorption of heavy metal ions by mesoporous ZnO and TiO2@ ZnO monoliths: adsorption and kinetic studies. Microchemical journal,145, 105-112.
 Chen, J., Wang, N., Liu, Y., Zhu, J., Feng, J., Yan, W. (2018). Synergetic effect in a self-doping polyaniline/TiO2 composite for selective adsorption of heavy metal ions. Synthetic metals,245, 32-41.
 World Health Organization, Geneva. (2010). WHO. Guidelines for drinking water Quality: Recommendations.
 Losi, M. E., Amrhein, C., Frankenberger, W. T. (1994). Environmental biochemistry of chromium. In reviews of environmental contamination and toxicology (pp. 91-121). Springer, New York, NY.
 Montgomery, D.C., 1991. Desing and Analysis of Experiments, 3rd ed. Wiley, New York.
 Fischer, R.A., (1925). Statistical methods for research workers, Oliver and Boyd, London.
 Sharififard, H., Nabavinia, M., Soleimani, M. (2017). Evaluation of adsorption efficiency of activated carbon/chitosan composite for removal of Cr (VI) and Cd (II) from single and bi-solute dilute solution. Advances in environmental technology,2(4), 215-227.
 Bayat, B. (2002). Comparative study of adsorption properties of Turkish fly ashes: I. The case of nickel (II), copper (II) and zinc (II). Journal of hazardous materials,95(3), 251-273.
 Azouaou, N., Sadaoui, Z., Djaafri, A., Mokaddem, H. (2010). Adsorption of cadmium from aqueous solution onto untreated coffee grounds: Equilibrium, kinetics and thermodynamics. Journal of hazardous materials,184(1-3), 126-134.
 Wang, F. Y., Wang, H., Ma, J. W. (2010). Adsorption of cadmium (II) ions from aqueous solution by a new low-cost adsorbent—Bamboo charcoal. Journal of hazardous materials,177(1-3), 300-306.
 Van, H. T., Nguyen, L. H., Nguyen, X. H., Nguyen, T. H., Nguyen, T. V., Vigneswaran, S., Tran, H. N. (2018). Characteristics and mechanisms of cadmium adsorption onto biogenic aragonite shells-derived biosorbent: Batch and column studies. Journal of environmental management, 241, 535-548.
 Jeon, C. (2018). Adsorption behavior of cadmium ions from aqueous solution using pen shells. Journal of industrial and engineering chemistry,58, 57-63.
 Asuquo, E. D., Martin, A. D. (2016). Sorption of cadmium (II) ion from aqueous solution onto sweet potato (Ipomoea batatas L.) peel adsorbent: characterisation, kinetic and isotherm studies. Journal of environmental chemical engineering,4(4), 4207-4228.