References

1. P.B. Tchounwou, C.G. Yedjou, A.K. Patlolla, D.J. Sutton, Heavy Metal Toxicity and the Environment, A. Luch, Ed., Molecular, Clinical and Environmental Toxicology, Experientia Supplementum, Vol. 101, Springer, Basel, 2012, pp. 133–164.
2. P.K. Gautam, R.K. Gautam, S. Banerjee, M.C. Chattopadhyaya, J.D. Pandey, Chapter 4 – Heavy Metals in the Environment: Fate, Transport, Toxicity and Remediation Technologies, D. Pathania, Ed., Heavy Metals: Sources Toxicity and Remediation Techniques, Nova Science Publishers, New York, USA, 2016, pp. 101–130.
3. H.R. Shamsollahi, M. Alimohammadi, S. Momeni, K. Naddafi, R. Nabizadeh, F.C. Khorasgani, M. Masinaei,
   M. Yousefi, Assessment of the health risk induced by accumulated heavy metals from anaerobic digestion of biological sludge of the lettuce, Biol. Trace Elem. Res., 188 (2019) 514–520.
4. J.E. Emurotu, P.C. Onianwa, Bioaccumulation of heavy metals in soil and selected food crops cultivated in Kogi State, North Central Nigeria, Environ. Syst. Res., 188 (2019) 514–520.
5. G. Issabayeva, S.Y. Hang, M.C. Wong, M.K. Aroua, A review on the adsorption of phenols from wastewater onto diverse groups of adsorbents, Rev. Chem. Eng., 34 (2018), doi: 10.1515/ revce-2017–0007.
6. A. Azari, M. Yeganeh, M. Gholami, M. Salari, The superior adsorption capacity of 2,4-dinitrophenol under ultrasoundassisted magnetic adsorption system: modeling and process optimization by central composite design, J. Hazard. Mater., 418 (2021) 126348, doi: 10.1016/j.jhazmat.2021.126348.
7. W. Raza, J. Lee, N. Raza, Y. Luo, K.-H. Kim, J. Yang, Removal of phenolic compounds from industrial waste water based on membrane-based technologies, J. Ind. Eng. Chem., 71 (2019) 1–18.
8. Y. Rashtbari, S. Hazrati, A. Azari, S. Afshin, M. Fazlzadeh, M. Vosoughi, A novel, eco-friendly and green synthesis of PPACZnO and PPAC-nZVI nanocomposite using pomegranate peel: cephalexin adsorption experiments, mechanisms, isotherms and kinetics, Adv. Powder Technol., 31 (2020) 1612–1623.
9. T.S. Hui, M.A.A. Zaini, Potassium hydroxide activation of activated carbon: a commentary, Carbon Lett., 16 (2015) 275–280.
10. B. Buczek, Preparation of active carbon by additional activation with potassium hydroxide and characterization of their properties, Adv. Mater. Sci. Eng., 2016 (2016) 5819208, doi:10.1155/2016/5819208.
11. Paryanto, W.A. Wibowo, D. Hantoko, M.E. Saputro, Preparation of activated carbon from mangrove waste by KOH chemical activation, IOP Conf. Ser.: Mater. Sci. Eng., 543 (2019) 012087,
    doi: 10.1088/1757-899X/543/1/012087.
12. R. Qadeer, N. Khalid, Removal of cadmium from aqueous solutions by activated charcoal, Sep. Sci. Technol., 40 (2005) 845–859.
13. B. Devi, A. Jahagirdar, M. Ahmed, Adsorption of chromium on activated carbon prepared from coconut shell, Adsorption, 2 (2012) 364–370.
14. A. Pal, H.-S. Kil, S. Mitra, K. Thu, B.B. Saha, S.-H. Yoon, J. Miyawaki, T. Miyazaki, S. Koyama, Ethanol adsorption uptake and kinetics onto waste palm trunk and mangrove based activated carbons, Appl. Therm. Eng., 122 (2017) 389–397.
15. F. Ngugi, J.M. Onyari, J.N. Wabomba, Efficacy of mangrove (Rhizophora mucronata) roots powder in adsorption of lead(II) ions from aqueous solutions: equilibrium and kinetics studies, IOSR J. Appl. Chem., 9 (2016) 45–51.
16. C.W. Oo, M.J. Kassim, A. Pizzi, Characterization and performance of Rhizophora apiculata mangrove polyflavonoid tannins in the adsorption of copper(II) and lead(II), Ind. Crops Prod., 30 (2009) 152–161.
17. J. Anwar, U. Shafique, Waheed-uz-Zaman, M. Salman, A. Dar, S. Anwar, Removal of Pb(II) and Cd(II) from water by adsorption on peels of banana, Bioresour. Technol., 101 (2010) 1752–1755.
18. N.F. Fahim, B.N. Barsoum, A.E. Eid, M.S. Khalil, Removal of chromium(III) from tannery wastewater using activated carbon from sugar industrial waste, J. Hazard. Mater., 136 (2006) 303–309.
19. N. Ayawei, A.N. Ebelegi, D. Wankasi, Modelling and interpretation of adsorption isotherms, J. Chem., 2017 (2017) 3039817, doi: 10.1155/2017/3039817.
20. S.M. Yakout, E. Elsherif, Batch kinetics, isotherm and thermodynamic studies of adsorption of strontium from aqueous solutions onto low cost rice-straw based carbons, Carbon – Sci. Technol., 3 (2010) 144–153.
21. Z. Wang, Y. Jiang, X. Mo, X. Gu, W. Li, Speciation transformation of Pb during palygorskite sorption-calcination process: implications for Pb sequestration, Appl. Geochem., 124 (2021) 104850, doi:10.1016/j.apgeochem.2020.104850.
22. J. Liu, X. Wu, Y. Hu, C. Dai, Q. Peng, D. Liang, Effects of Cu(II) on the adsorption behaviors of Cr(III) and Cr(VI) onto kaolin, J. Chem., 2016 (2016) 3069754, doi: 10.1155/2016/3069754.
23. U. Beker, B. Ganbold, H. Dertli, D.D. Gülbayir, Adsorption of phenol by activated carbon: influence of activation methods and solution pH, Energy Convers. Manage., 51 (2010) 235–240.
24. B. Xie, J. Qin, S. Wang, X. Li, H. Sun, W. Chen, Adsorption of phenol on commercial activated carbons: modelling and interpretation, Int. J. Environ. Res. Public Health, 17 (2020) 789, doi: 10.3390/ijerph17030789.
25. S.Z. Mohammadi, M.A. Karimi, D. Afzali, F. Mansouri, Removal of Pb(II) from aqueous solutions using activated carbon from sea-buckthorn stones by chemical activation, Desalination, 262 (2010) 86–93.
26. N. Bouchelkia, L. Mouni, L. Belkhiri, A. Bouzaza, J.C. Bollinger, K. Madani, F. Dahmoune, Removal of lead(II) from water using activated carbon developed from jujube stones, a low-cost sorbent, Sep. Sci. Technol., 51 (2016) 1645–1653.
27. E.-W.A. Abou El-Maaty, Removal of lead from aqueous solution on activated carbon and modified activated carbon prepared from dried water hyacinth plant, J. Anal. Bioanal. Technol., 5 (2014) 1000187, doi:10.4172/2155-9872.1000187.
28. M.H. Al-Malack, M. Dauda, Competitive adsorption of cadmium and phenol on activated carbon produced from municipal sludge, J. Environ. Chem. Eng., 5 (2017) 2718–2729.
29. J.A. Arcibar-Orozco, J.R. Rangel-Mendez, P.E. Diaz-Flores, Simultaneous adsorption of Pb(II)-Cd(II), Pb(II)-phenol, and Cd(II)-phenol by activated carbon cloth in aqueous solution, Water Air Soil Pollut., 226 (2015) 2197, doi: 10.1007/ s11270-014-2197-1.
30. H.S. Mohamed, N.K. Soliman, D.A. Abdelrheem, A.A. Ramadan, A.H. Elghandour, S.A. Ahmed, Adsorption of Cd2+ and Cr3+ ions from aqueous solutions by using residue of Padina gymnospora waste as promising low-cost adsorbent, Heliyon, 5 (2019) e01287, doi: 10.1016/j.heliyon.2019.e01287.
31. A. Alemu, B. Lemma, N. Gabbiye, K.Y. Foo, Adsorption of chromium(III) from aqueous solution using vesicular basalt rock, Cogent Environ. Sci., 5 (2019) 1650416, doi: 10.1080/23311843.2019.1650416.
32. C. Faur-Brasquet, K. Kadirvelu, P. Le Cloirec, Removal of metal ions from aqueous solution by adsorption onto activated carbon cloths: adsorption competition with organic matter, Carbon N. Y., 40 (2002) 2387–2392.
33. C. Moreno-Castilla, M.A. Álvarez-Merino, M.V. López-Ramón, J. Rivera-Utrilla, Cadmium ion adsorption on different carbon adsorbents from aqueous solutions. Effect of surface chemistry, pore texture, ionic strength, and dissolved natural organic matter, Langmuir, 20 (2004) 8142–8148.
34. A.A. Basaleh, M.H. Al-Malack, T.A. Saleh, Methylene blue removal using polyamide-vermiculite nanocomposites: kinetics, equilibrium and thermodynamic study, J. Environ. Chem. Eng., 7 (2019) 103107, doi: 10.1016/j.jece.2019.103107.
35. W. Zhu, W. Yao, Y. Zhan, Y. Gu, Phenol removal from aqueous solution by adsorption onto solidified landfilled sewage sludge and its modified sludges, J. Mater. Cycles Waste Manage., 17 (2015) 798–807.
36. M. Karnib, A. Kabbani, H. Holail, Z. Olama, Heavy metals removal using activated carbon, silica and silica activated carbon composite, Energy Procedia, 50 (2014) 113–120.
37. C. Duan, T. Ma, J. Wang, Y. Zhou, Removal of heavy metals from aqueous solution using carbon-based adsorbents: a review, J. Water Process Eng., 37 (2020) 101339, doi: 10.1016/j. jwpe.2020.101339.
38. Y. Fu, Y. Shen, Z. Zhang, X. Ge, M. Chen, Activated bio-chars derived from rice husk via one- and two-step KOH-catalyzed pyrolysis for phenol adsorption, Sci. Total Environ., 646 (2019) 1567–1577.
39. C. Valderrama, X. Gamisans, X. de las Heras, A. Farrán, J.L. Cortina, Sorption kinetics of polycyclic aromatic hydrocarbons removal using granular activated carbon: intraparticle diffusion coefficients, J. Hazard. Mater., 157 (2008) 386–396.
40. N.G. Rincón-Silva, J.C. Moreno-Piraján, L.G. Giraldo, Thermodynamic study of adsorption of phenol, 4-chlorophenol, and 4-nitrophenol on activated carbon obtained from eucalyptus seed, J. Chem., 2015 (2015) 569403, doi: 10.1155/2015/569403.
41. M.A. Ahmad, N.A. Ahmad Puad, O.S. Bello, Kinetic, equilibrium and thermodynamic studies of synthetic dye removal using pomegranate peel activated carbon prepared by microwaveinduced KOH activation, Water Resour. Ind., 6 (2014) 18–35.
42. R. Berenguer, J.P. Marco-Lozar, C. Quijada, D. Cazorla-Amorós, E. Morallón, Electrochemical regeneration and porosity recovery of phenol-saturated granular activated carbon in an alkaline medium, Carbon N.Y., 48 (2010) 2734–2745.
43. B. Özkaya, Adsorption and desorption of phenol on activated carbon and a comparison of isotherm models,
    J. Hazard. Mater., 129 (2006) 158–163.
44. K. Rinkus, B.E. Reed, W. Lin, NaOH regeneration of Pb and phenol-laden activated carbon. I. Batch study results, Sep. Sci. Technol., 32 (1997) 2367–2384.
45. T.D. Šoštarić, M.S. Petrović, F.T. Pastor, D.R. Lončarević, J.T. Petrović, J.V. Milojković, M.D. Stojanović, Study of heavy metals biosorption on native and alkali-treated apricot shells and its application in wastewater treatment, J. Mol. Liq., 259 (2018) 340–349.
46. T.S. Anirudhan, S.S. Sreekumari, Adsorptive removal of heavy metal ions from industrial effluents using activated carbon derived from waste coconut buttons, J. Environ. Sci., 23 (2011) 1989–1998.