Removal of Cationic Heavy Metal and HOC from Soil-Washed Water Using Activated Carbon

Soil washing process with a surfactant solution is a potential technology for the rapid removal of hydrophobic organic compound (HOC) from soil. However, large amount of washed water would be produced during operation and this should be treated effectively by proper methods. The soil washed water for complex contaminated site with HOC and heavy metals might contain high amount of pollutants such as HOC and heavy metals as well as used surfactant. The heavy metals in the soil washed water have toxic effects on microbial activities thus these should be removed from the washed water before proceeding to a biological waste-water treatment system. Moreover, the used surfactant solutions are necessary to be recovered for reducing the soil washing operation cost. In order to simultaneously remove the heavy metals and HOC from soil-washed water, activated carbon (AC) was used in the present study. In an anionic-nonionic surfactant mixed solution, the Cd(II) and phenanthrene (PHE) were effectively removed by adsorption on activated carbon. The removal efficiency for Cd(II) was increased from 0.027 mmol-Cd/g-AC to 0.142 mmol-Cd/g-AC as the mole ratio of SDS increased in the presence of PHE. The adsorptive capacity of PHE was also increased according to the SDS mole ratio due to the decrement of molar solubilization ratios (MSR) for PHE in an anionic-nonionic surfactant mixture. The simultaneous adsorption of HOC and cationic heavy metals using activated carbon could be a useful method for surfactant recovery and the reduction of heavy metal toxicity in a surfactant-enhanced soil washing process.





References:
[1] S.H. Woo, J.M. Park, and B.E. Rittmann, Evaluation of the interaction
between biodegradation and sorption of phenanthrene in soil-slurry
systems. Biotechnol., Bioeng., vol. 73, pp. 12-24, 2001.
[2] L. Yang, S. Wu, and B. Xing, Enhanced soil washing of phenanthrene by
mixed solutions of TX100 and SDBS, Environ. Sci. Technol., vol. 40, pp.
4274-4280. 2006.
[3] C.C. West, and J.F. Harwell, Surfactant and subsurface remediation,
Environ. Sci. Technol., vol. 26, pp. 2324-2330, 1992.
[4] C.N. Mulligan, R.N. Yong, and B.F. Gibbs, Surfactant-enhanced
remediation of contaminated soil: a review, Eng. Geol., vol. 60, pp.
371-380, 2001.
[5] B. Zhao, L. Zhu, W. Li, and B. Chen, Solubilization and biodegradation of
phenanthrene on mixed anionic-nonionic surfactant solution,
Chemosphere, vol. 58, pp. 33-40, 2005.
[6] W. Zhou, and L. Zhu, Enhanced desorption of phenanthrene from
contaminated soil using anionic/nonionic mixed surfactant. Environ.
Pollut., vol. 147, pp. 350-357, 2007.
[7] H. Yu, L. Zhu, and W. Zhou, Enhanced desorption and biodegradation of
phenanthrene in soil-water systems with the presence of anionic-nonionic
mixed surfactants, J. Hazard. Mater., vol. 142, pp. 354-361, 2007.
[8] R-a, Doong, T-W, Wu, and W-g. Lei, Surfactant enhanced remediation of
cadmium contaminated soils, Water Sci. Tech., vol. 37, pp. 65-71, 1998.
[9] A.S. Ramamurthy, D. Vo, X.J., Li, and J. Qu, Surfactant-enhanced
removal of Cu(II) and Zn(II) from a contaminated sandy soil. Water Air
Soil Pollut., vol. 190, pp. 197-207, 2008.
[10] M.A. Providenti, H. Lee, and J.T. Trevors, Selected factors limiting the
microbial degradation of recalcitrant compounds, J. Industrial
Microbiology, vol. 12, pp. 379-395, 1993.
[11] D.F. Lowe, C.L. Oubre, and C.H. Ward, Reuse of surfactant and
cosolvents for NAPL remediation, Lewis Publishers, Boca Raton, 2000.
[12] H.P. Boehm, Chemical identification of surface groups in advanced in
catalysis, vol. 16, Academic Press, New York, pp. 179-274, 1966.
[13] C.K. Ahn, D. Park, S.H. Woo, and J.M. Park, Removal of cationic heavy
metal from aqueous solution by activated carbon impregnated with
anionic surfactants, J. Hazard. Mater.,
DOI:10.1016/j.hazmat.2008.09.036, accepted, 2008.
[14] C.K. Ahn, Y.M. Kim, S.H. Woo, and J.M. Park, Selective adsorption of
phenanthrene dissolved in surfactant solution using activated carbon,
Chemosphere, vol. 69, pp. 1681-1688, 2007.
[15] R.W. Walters, and R.G. Luthy, Equilibrium adsorption of polycyclic
aromatic hydrocarbons from water onto activated carbon, Environ. Sci.
Technol., vol 18, pp. 395-403, 1984.
[16] Z. Liu, D.A. Edwards, and R.G. Luthy, Sorption of non-ionic surfactants
onto soil, Water Res., vol. 26, pp. 1337-1345, 1992.
[17] N. Narkis, B. and Ben-David, Adsorption of non-ionic surfactants on
activated carbon and mineral clay, Water Res, vol. 19, pp. 815-824, 1985.
[18] T. Hayashita, and R.A. Bartsch, Competitive sorption of alkali-metal and
alkaline-earth-metal cations by carboxylic acid resins containing acyclic
or cyclic polyether units, Analytical Chemistry, vol. 63, pp. 1847-1850,
1991.
[19] C. Pelekani, and V.L. Snoeyink, Competitive adsorption between atrazine
and methylene blue on activated carbon: the important of pore size
distribution, Carbon, vol. 38, pp. 1423-1436, 2000.
[20] L. Monser, M.B. Amor, and M. Ksibi, Purification of wet phosphoric acid
using modified activated carbon, Chem. Eng. Process, vol. 38, pp.
267-271, 1999
[21] C.A. Başar, A. Karagunduz, B. Keskinler, A. Cakici, Effect of presence of
ions on surface characteristics of surfactant modified powdered activated
carbon (PAC), Appl. Surf. Sci., vol. 218, pp. 169-174, 2003.