Isotherm Study of Crystal Violet on Activated Carbon Synthesized from Millet Stover

Author(s): Salahudeen N.*, Abubakar M.

Affiliation(s): Department of Chemical and Petroleum Engineering, Bayero University, Kano 700281, Nigeria

*Corresponding Author’s Address: [email protected]

Issue: Volume 9, Issue 2 (2022)

Submitted: March 20, 2022
Accepted for publication: July 22, 2022
Available online: September 5, 2022

Salahudeen, N, Abubakar, M. (2022). Isotherm study of crystal violet on activated carbon synthesized from millet stover. Journal of Engineering Sciences, Vol. 9(2), pp. F1-F5, doi: 10.21272/jes.2022.9(2).f1

DOI: 10.21272/jes.2022.9(2).f1

Research Area:  CHEMICAL ENGINEERING: Processes in Machines and Devices

Abstract. Continuous release of synthetic dyes from industrial effluent into surface water poses a huge environmental threat and health hazard to humans and aquatic life. The need to right the wrong occasioned by the inimical industrial practice of uncontrolled release of carcinogenic dyes into the surface water calls for research into effective treatment technologies for the treatment of dye-contaminated industrial effluent. The isotherm of Crystal Violet (CV) solution on activated carbon (AC) synthesized from millet stover was investigated and presented herein. Samples of AC were synthesized from millet stover at 120⁰C using phosphoric acid as the activating agent. Employing varying mix ratios of stover-to-phosphoric acid (1:0, 1:1, 1:2, 1:3, and 1:4), respective samples of AC were synthesized. The batch adsorption process of the various samples of the AC in 15 mg/l initial concentration of an aqueous solution of CV was carried out at varying times. The CV’s change in the sorbate’s concentration was monitored using a UV spectrophotometer. The optimum adsorption time was 240 min. The optimally synthesized activated carbon was the 1:2 sample having an equilibrium sorbent concentration of 0.74 mg/L and sorbate uptake of 95.1%. Langmuir, Freundlich and Temkin isotherm models were employed for the isotherm analysis. The  values of the Langmuir, Freundlich and Temkin models were 0.99, 0.90, and 0.94, respectively. The isotherm constants for the Langmuir, Freundlich and Temkin models were –1.52 l/mg, –4.08, and 0.005 l/min, respectively. The Langmuir isotherm model best fitted the adsorption mechanism with a maximum equilibrium adsorption capacity of 14.0 mg/g.

Keywords: millet stover, activated carbon, crystal violet, isotherm model.


  1. Samsuri, A., Sadegh-Zadeh, F., Seh-Bardan, B. (2014). Characterization of biochars produced from oil palm and rice husks and their adsorption capacities for heavy metals. Int J Environ Sci Technol, Vol. 11, pp. 967-976.
  2. Yousefi, M., Arami, S., Takallo, M. (2019). Modification of pumice with HCl and NaOH enhancing its fluoride adsorption capacity: kinetic and isotherm studies. Hum Ecol Risk Assess, Vol. 25, pp. 1508-1520.
  3. Rahman, M. M., Bari, Q. H., Mohammad, N., Ahsan, A., Sobuz, H. R., Uddin, M. A. (2013). Characterization of rice husk carbon produced through simple technology. Adv. Mater. Sci. Appl., Vol. 2 (1), pp. 25-30.
  4. Alvarez, J., Lopez, G., Amutio, M., Bilbao, J., Olazar, M. (2014). Upgrading the rice husk char obtained by flash pyrolysis for the production of amorphous silica and high quality activated carbon. Bioresour. Technol., Vol. 170, pp. 132–137.
  5. Boopathy, R., Karthikeyan, S. (2013). Adsorption of ammonium ion by coconut shell-activated carbon from aqueous solution: kinetic, isotherm, and thermodynamic studies. Env. Sci Pollut Res., Vol. 20, pp. 533-542.
  6. Kini, S. M., Saidutta, M. B., Murty, R. V., Kadoli, S. V. (2015). Adsorption of basic dye from aqueous solution using HCl treated saw dust (Lagerstroemia microcarpa): kinetic, modeling of equilibrium, thermodynamic. International Research Journal of Environment Sciences, Vol. 2 (8), pp. 6-16.
  7. Saueprasearsit, P. (2011). Adsorption of chromium (Cr+6) using durian peel. Intl Conf on Biotechnology and Environment Management, Singapore, Vol. 18, pp. 33-38.
  8. Srikun, S., Hirunpraditkoon, S., Nuithitikul, K. (2011). Lead adsorption of activated carbon synthesized from durian peel. Adv. Fluid Mechnics Heat. Mass Transf., Vol. 2011, pp. 66-71.
  9. Cui, X., Jia, F., Chen, Y., Gan, J. (2011). Influence of single-walled carbon nanotubes on microbial availability of phenanthrene in sediment. Ecotoxicology, Vol. 20, pp. 1277-1285.
  10. Khadhri, N., Saad, M. E. K., Mosbah, M., Moussaoui, Y. (2019). Batch and continuous column adsorption of indigo carmine onto activated carbon derived from date palm petiole. J Environ Chem Eng., Vol. 7, 102775.
  11. Alwi, R. S., Gopinathan, R., Bhowal, A., Garlapati, C. (2020). Adsorption characteristics of activated carbon for the reclamation of eosin Y and indigo carmine colored effluents and new isotherm model. Molecules, Vol. 25(24), 6014.
  12. Bedia, J., Peñas-Garzón, M., Gómez-Avilés, A., Rodriguez, J. J., Belver, C. (2020). Review on activated carbons by chemical activation with FeCl3. Journal of Carbon Research, Vol. 6(2), 21.
  13. Huang, Y., Zhao, G. (2016). Preparation and characterization of activated carbon fibers from liquefied wood by KOH activation. Holzforschung, Vol. 70, pp. 195-202.
  14. Heidarinejad, Z., Dehghani, M. H., Heidar, M., Javedan, G., Sillanpaa, I. A. M. (2020). Methods for preparation and activation of activated carbon: A review. Environmental Chemistry Letters, Vol. 18, pp. 393-415.
  15. Somsesta, N., Sricharoenchaikul, V., Aht-Ong, D. (2020). Adsorption removal of methylene blue onto activated carbon/cellulose biocomposite films: Equilibrium and kinetic studies. Mater. Chem. Phys., Vol. 240, 122221.
  16. Zakaria, R., Jamalluddin, N. A., Bakar, Z. M. A. (2021). Effect of impregnation ratio and activation temperature on the yield and adsorption performance of mangrove based activated carbon for methylene blue removal. Results in Materials, Vol. 10, 100183.
  17. Islam, M. A., Chowdhury, M. A., Mozumder, M. S. I., Uddin, M. T. (2021). Langmuir adsorption kinetics in liquid media: Interface Reaction Model. ACS Omega, Vol. 6, pp. 14481-14492.
  18. Das, B., Mondal, N. K., Bhaumik, R., Roy, P. (2014). Insight into adsorption equilibrium, kinetics and thermodynamics of lead onto alluvial soil. Int. J. Environ. Sci. Technol., Vol. 11, pp. 1101-1114.

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