Tran Dinh Trinh, Nguyen Thi Hoai Phuong

Main Article Content

Abstract

Magnetic biochar materials were synthesized by heating rice husk at 500°C under nitrogen environment, then fixing iron oxides on biochar surface using hydrothermal method applied to Fe(OH)2 and Fe(OH)3 which were generated from respective precursors Fe2+ and Fe3+ in alkaline environment. The presence of iron oxides on the surface of biochar and the surface characteristics of iron-composite materials were studied with the aid of modern physicochemical analysis techniques (SEM/EDX, BET, FT-IR, XRD). Magnetic biochar materials were relatively porous, with an average spectific surface area of 62.1 m2, an average capillary size of about 17.2 nm. The mixture of iron oxide particles were revealed within the nano scale (about 15 nm). The methylene blue adsorption efficiency depended upon the amount of adsorbent, adsorption time, pH of solution and pollutant concentrations. Specifically, the optimal conditions for maximum adsorption efficiency were as follows: 0.02 g/L of magnetic biochar, the adsorption equilibrium time was 3 hours at room temperature, in a solution of pH7; The efficiency of methylene blue adsorption in optimal conditions reached over 98.82%. The Langmuir and Freundlich isotherm adsorption models all described well the methylene blue adsorption process at room temperature, with the regression coefficients R2 of 95.0 and 90.0, respectively. The maximum adsorption capacity of methylene blue calculated by Langmuir model was 22.4 mg/g.


Keywords: Biochar, mangetic composite, methylene blue, adsorption.

 

References

[1] A.F. Baybars, Ö. Cengiz, K. Mustafa, Cationic Dye (Methylene Blue) Removal from Aqueous Solution by Montmorillonite, Bulletin of the Korean Chemical Society 33 (2012) 3184–3190. https://doi.org/10.5012/bkcs.2012.33.10.3184.
[2] Md. Juned, K. Ahmed, M. Ahmaruzzaman, A facile synthesis of Fe3O4 - charcoal composite for the sorption of a hazardous dye from aquatic environment, Journal of Environmental Management 163(2015) 163–173. https://doi.org/ 10.1016/j.jenvman.2015.08.011.
[3] J.S. Cha, S.H. Park, S.-C. Jung, C. Ryu, J.-K. Jeon, M.- C. Shin, Production and Utilization of Biochar: A Review, Journal of Industrial and Engineering Chemistry 40 (2016) 1–15. https:// doi.org/10.1016/j.jiec.2016.06.002.
[4] J.M. Novak, W.J. Busscher, D.W. Watts, D.A. Laird, M.A. Ahmedna, M.A.S. Niandou, Short-term CO2 mineralization after additions of biochar and switchgrass, Geoderma 154 (2010) 281-288. https://doi.org/10.1016/j.geoderma.2009. 10.014
[5] Y. Zhang, Z. Li, I.B. Mahmood, Recovery of NH4+ by corn cob produced biochars and its potential application as soil conditioner, Journal of Environmental Science and Engineering 8 (2014) 825–834. https://doi.org/10.1007/s11783-014-0682-9.
[6] Md.J.K. Ahmed, M. Ahmaruzzaman, R.A. Reza, Lignocellulosic-derived modified agricultural waste: development, characterisation and implementation in sequestering pyridine from aqueous solutions, Journal of Colloid and Interface Science 428 (2014) 222–234. https:// doi.org/10.1016/j.jcis.2014.04.049.
[7] Y.-R. Zhang, S.-Q. Wang, S.-L. Shen, B.-X. Zhao, A novel water treatment magnetic nanomaterial for removal of anionic and cationic dyes under severe condition, Chemical Engineering Journal 233 (2013) 258-264. https: //doi.org/10.1016/j.cej.2013.07.009.
[8] L. Ai, C. Zhang, F. Liao, Y. Wang, M. Li, L. Meng, J. Jiang, Removal of methylene blue from aqueous solution with magnetite loaded multi-wall carbon nano tube: kinetics, isotherm and mechanism analysis, Journal of Hazardous Materials 198 (2011) 282–290. https://doi.org/10. 1016/j.jhazmat.2011.10.041.
[9] R. Li, J.J. Wang, B. Zhou, Z. Zhang, S. Liu, S. Lei, R. Xiao, Simultaneous capture removal of phosphate, ammonium and organic substances by MgO impregnated biochar and its potential use in swine wastewater treatment, Journal of Cleaner Production 147 (2017) 96–107. https://doi.org/ 10.1016/j.jclepro.2017.01.069.
[10] C-D. Dong., C-W. Chen., C-M. Kao., C-C. Chien and C-M. Hung. Wood-Biochar-Supported Magnetite Nanoparticles for Remediation of PAH-Contaminated Estuary Sediment, Catalysts 8 (2018) 1-13. https://doi.org/10.3390/catal8020073.
[11] D. Mohan., H. Kumar, A. Saraswat., M. Alexandre - Franco., C.U. Pittman Jr, Cadmium and Lead Remediation using Magnetic Oak Wood and Oak Bark Fast Pyrolysis Bio-chars, Chemical Engineering Journal 236 (2014) 513–528. https:// doi.org/10.1016/j.cej.2013.09.057.
[12] C. Baoliang, C. Zaiming, L. Shaofang, A novel magnetic biochar efficiently sorbs organic pollutants and phosphate, Bioresource Technology 102 (2011) 716–723. https://doi.org/ 10.1016/j.biortech.2010.08.067.
[13] W. Guo., S. Wang., Y. Wang., S. Lu., Y. Gao. Sorptive removal of phenanthrene from aqueous solutions using magnetic and non-magnetic rice husk-derived biochars, R. Soc. open sci. 5 (2018) 1-11. http://dx.doi.org/10.1098/rsos.172382.
[14] O. Xin, H. Yitong, C. X. and C. Jiawei, Magnetic biochar combining adsorption and separation
recycle for removal of chromium in aqueous solution, Water Science & Technology 75 (2016) 1175 -1184. https://doi.org/10.2166/wst.2016.610.