Equilibrium, Kinetic and Adsorption Mechanisms of Chromium (VI) on Characterized Activated Carbon Synthesized from Phosphoric Acid Activation of Coconut Shells
International Journal of Environmental Monitoring and Analysis
Volume 6, Issue 3, June 2018, Pages: 84-94
Received: May 15, 2018;
Accepted: Jun. 6, 2018;
Published: Jul. 25, 2018
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Hakeem Seidu, School of Environmental Science and Engineering, Suzhou University of Science & Technology, Suzhou, China
Dapeng Li, School of Environmental Science and Engineering, Suzhou University of Science & Technology, Suzhou, China
Jing Zhou, School of Environmental Science and Engineering, Suzhou University of Science & Technology, Suzhou, China
Over the years, water pollution due primarily to the discharge of toxic heavy metals from industrial activities has served as a major challenge in our quest to provide clean drinking water to millions of people across the world. Numerous cheap and environmentally friendly methods and technologies have been developed for the treatment of wastewater contaminated with heavy metals. Key among these technologies is the use of adsorbent as it is the most economical and efficient. In this present study, coconut shells were used to develop microporous adsorbent (activated carbon) through chemical activation by phosphoric acid (H3PO4). An analysis of the effect of various process parameters such as pH, temperature, initial metal ion concentration, adsorbent dose and contact time was conducted through batch adsorption of hexavalent chromium [Cr (VI)] on prepared AC sample. Initial Cr (VI) concentration was investigated through a range of 10 – 50 mg/L with the study showing an optimum concentration for AC of 20 mg/L for percentage removal (93.3%) but adsorption capacity (Qe) was highest for 50 mg/L (4.512 mg/g). The optimum conditions for adsorbent dose, contact time and temperature were determined as 6 g/L, 100 minutes and 30°C respectively for the prepared AC. Maximum adsorption was recorded for pH (2) at 88.2 5% (removal) and 4.41 mg/g (adsorption capacity) for AC. The experimental data obtained were modelled using various isotherms, including adsorption equilibrium isotherms, adsorption kinetic study and adsorption mechanisms with positive correlations (better fit) obtained for Freundlich isotherm, D-R isotherm (slightly), pseudo-second-order kinetic and Boyd models.
Equilibrium, Kinetic and Adsorption Mechanisms of Chromium (VI) on Characterized Activated Carbon Synthesized from Phosphoric Acid Activation of Coconut Shells, International Journal of Environmental Monitoring and Analysis.
Vol. 6, No. 3,
2018, pp. 84-94.
Gautam, R. K., Sharma, S. K., Mahiya, S., and Chattopadhyaya, M. C. (2015). Contamination of Heavy Metals in Aquatic Media: Transport, Toxicity and Technologies for Remediation. In Heavy Metals In Water: Presence, Removal and Safety (pp. 1–24).
Jaishankar, M., Mathew, B. B., Shah, M. S., and Gowda, K. R. S. (2014). Biosorption of Few Heavy Metal Ions Using Agricultural Wastes. Journal of Environment Pollution and Human Health.
Rahman, M. M., Adil, M., Yusof, A. M., Kamaruzzaman, Y. B., and Ansary, R. H. (2014). Removal of heavy metal ions with acid-activated carbons derived from oil palm and coconut shells. Materials, 7 (5), 3634–3650.
Chen, J., Zhang, L., Yang, G., Wang, Q., Li, R., and Lucia, L. A. (2017). "Preparation and characterization of activated carbon from hydrochar by phosphoric acid activation and its adsorption performance in prehydrolysis liquor," BioRes. 12 (3), 5928-5941.
Song J, Wang L, Song G. (2014). Research on influence factors on determination of specific surface area of carbon material by N2 adsorption method. Journal of applied science and engineering innovation Vol. 1 No. 1
Raj K Vyas, Shashi & Surendra Kumar (2014). Determination of micropore volume and surface area of zeolite molecular sieves by D-R and D-A equations: A comparative Study. Indian Journal of Chemical Technology, Vol. 11, pp. 704-709.
Tongpoothorn, W., Sriuttha, M., Homchan, P., Chanthai, S., and Ruangviriyachai, C. (2011). Preparation of activated carbon derived from Jatropha curcas fruit shell by simple thermo-chemical activation and characterization of their physic-chemical properties. Chemical Engineering Research and Design, 89, p. 335-340.
Zhao, J., Yang, L., Li, F., Yu, R., and Jin, C. (2009). Structural evolution in the graphitization process of activated carbon by high-pressure sintering. Carbon, 47, 744-751.
Acharya, J., Sahu, J. N., Sahoo, B. K., Mohanty, C. R., and Meikap, B. C. (2009). Removal of chromium (VI) from wastewater by activated carbon developed from Tamarind wood activated with zinc chloride. Chemical Engineering Journal, 150 (1), 25–39.
Al-Jabari, Maher (2016). Kinetic model for adsorption on mineral particles comparison between Langmuir kinetics and mass transfer. Journal of Environmental Technology & Innovation 6, pp. 27–37.
Wu, Q., Zhao, J., Qin, G., Wang C., Tong, X., Xue, S. (2013). Photocatalytic reduction of Cr (VI) with TiO2 film under visible light. Applied Catalysis B: Environmental, Vol. 142-143, pp. 142-148.
Yang, J., Yu, M., & Qiu T. (2014). Adsorption thermodynamics and kinetics of Cr (VI) on KIP210 resin.
Cao, R., Fan, M., Hu, J., Ruan, W., Wu, X., & Wei, X. (2018). Artificial Intelligence Based Optimization for the Se (VI) Removal from Aqueous Solution by Reduced Graphene Oxide-Supported Nanoscale Zero-Valent Iron Composites. US National Library of Medicine: National Institute of Health. Vol. 11 (3), pp. 428.
Youssef, S., El-Khouly S., & El-Nabarawy T. H. (2008). Removal of Pb (II) and Cd (II) from aqueous solution using activated carbons from pecan shells: Carbon Lett, 9, pp. 8-13.
Ayawei N., Ebelegi A. N., & Wankasi D. (2017). Modelling and Interpretation of Adsorption Isotherms. Journal of Chemistry, Volume 1, ArticleID 3039817, pp. 1 -11.
Boudrahem, F., Aissani-Benissad, H., and Aït-Amar, (2009). Sorption dynamics and equilibrium for the removal of lead ions from aqueous phase using activated carbon from coffee residue activated with ZnCl2. Journal of Environmental Management, 90, p. 3031- 3039.
Karthikeyan, S., Balasubramanian, R., and Iyer, C. S. P. (2007). Evaluation of the marine algae Ulva fasciata and Sargassum sp. For the biosorption of Cu (II) from aqueous solutions. Bioresource Technology, 98 (2), p. 452-455.
Sankar, K. R., Venkatraman B. R., & Arivoli S. (2013). Equilibrium and Thermodynamic Studies on the Removal of Iron (III) onto Plater of Paris. International Journal of Engineering Innovation & Research, Vol. 2, ISSN: 2277-5668.
Wang, L., Zhang, J., Zhao, R., Li, Y., Li, C., and Zhang, C. (2010). Adsorption of Pb (II) on activated carbon prepared from Polygonum orientale Linn: kinetics, isotherms, pH, and ionic strength studies. Bioresource Technology, p. 5808-5814.
Doke, K. M., Khan, E. M. (2017) Equilibrium, Kinetic and diffusion mechanisms of Cr (VI) adsorption onto activated carbon derived from wood apple shell. Journal of Chemistry, Vol. 10, pp. S252–S260.