Effective Removal of Nitrates Ions from Aqueous Solution Using New Clay as Potential Low-Cost Adsorbent
ABSTRACT
In the present study, we investigated the performance of clay mineral originated from a dam situated in Morocco (Agadir city), as natural, low-cost, alternative and eco-friendly adsorbent for removal of nitrates ions from aqueous solution within a batch process. The clay was characterized by X-ray diffraction, Scanning Electron Microscopy (SEM), Dispersive Energy of Spectroscopy (EDS), Fourier Transform Infrared (FTIR) and surface area analysis (BET). The effects of various experimental parameters are examined such as contact time, initial concentration of pollutant, adsorbent mass and solution pH. The removal of nitrate was 71.89% at natural pH (pH = 5.1) using 1 g/l of adsorbent in 500 ml of nitrate solution having initial concentration of 300 mg/l (effect of contact time). Adsorption kinetic study revealed that the adsorption process followed first order kinetic. Theoretical correlation of the experimental equilibrium adsorption data for the Nitrate-New Clay system was properly explained by the Langmuir isotherm model. The maximum adsorption capacity was Qm, exp = 244.06 mg/g at 20℃ and at natural pH (with Qm, cal = 250 mg/g). An increase in adsorbent dosage increased the percent removal of nitrate, R = 1 g/l was considered as optimum dose and was used for further study. The pH heavily affected the adsorption capacity, and the percentage removal was found to decrease with increase in pH. The obtained results indicated that this New Clay (NC) was very good adsorbent for NO3-, interesting alternative material with respect to more costly adsorbent used, and could be used as a highly efficient adsorbent for the separation of nitrate from drinking or waste water.
In the present study, we investigated the performance of clay mineral originated from a dam situated in Morocco (Agadir city), as natural, low-cost, alternative and eco-friendly adsorbent for removal of nitrates ions from aqueous solution within a batch process. The clay was characterized by X-ray diffraction, Scanning Electron Microscopy (SEM), Dispersive Energy of Spectroscopy (EDS), Fourier Transform Infrared (FTIR) and surface area analysis (BET). The effects of various experimental parameters are examined such as contact time, initial concentration of pollutant, adsorbent mass and solution pH. The removal of nitrate was 71.89% at natural pH (pH = 5.1) using 1 g/l of adsorbent in 500 ml of nitrate solution having initial concentration of 300 mg/l (effect of contact time). Adsorption kinetic study revealed that the adsorption process followed first order kinetic. Theoretical correlation of the experimental equilibrium adsorption data for the Nitrate-New Clay system was properly explained by the Langmuir isotherm model. The maximum adsorption capacity was Qm, exp = 244.06 mg/g at 20℃ and at natural pH (with Qm, cal = 250 mg/g). An increase in adsorbent dosage increased the percent removal of nitrate, R = 1 g/l was considered as optimum dose and was used for further study. The pH heavily affected the adsorption capacity, and the percentage removal was found to decrease with increase in pH. The obtained results indicated that this New Clay (NC) was very good adsorbent for NO3-, interesting alternative material with respect to more costly adsorbent used, and could be used as a highly efficient adsorbent for the separation of nitrate from drinking or waste water.
Cite this paper
El Ouardi, M. , Qourzal, S. , Alahiane, S. , Assabbane, A. and Douch, J. (2015) Effective Removal of Nitrates Ions from Aqueous Solution Using New Clay as Potential Low-Cost Adsorbent. Journal of Encapsulation and Adsorption Sciences, 5, 178-190. doi: 10.4236/jeas.2015.54015.
El Ouardi, M. , Qourzal, S. , Alahiane, S. , Assabbane, A. and Douch, J. (2015) Effective Removal of Nitrates Ions from Aqueous Solution Using New Clay as Potential Low-Cost Adsorbent. Journal of Encapsulation and Adsorption Sciences, 5, 178-190. doi: 10.4236/jeas.2015.54015.
References
[1] Jeong, J.Y., Kim, H.K., Kim, J.H. and Park, J.Y. (2012) Electrochemical Removal of Nitrate Using ZVI Packed Bed Bipolar Electrolytic Cell. Chemosphere, 89, 172-178.
http://dx.doi.org/10.1016/j.chemosphere.2012.05.104 [2] Zhou, M., Fu, W., Gu, H. and Lei, L. (2007) Nitrate Removal from Groundwater by a Novel Three-Dimensional Electrode Biofilm Reactor. Electrochimica Acta, 52, 6052-6059.
http://dx.doi.org/10.1016/j.electacta.2007.03.064 [3] Thomson, T.S. (2001) Nitrate Concentration in Private Rural Drinking Water Supplies in Saskatchewan Canada. Bulletin of Environmental Contamination and Toxicology, 66, 64-70.
http://dx.doi.org/10.1007/s001280000206 [4] Majumdar, D. and Gupta, N. (2000) Nitrate Pollution of Groundwater and Associated Human Health Disorders. Indian Journal of Environmental Health, 42, 28-39. [5] Tate, C.H. and Arnold, K.F. (1990) Health and Aesthetic Aspects of Water Quality. In: Pontius, F.W., Ed., Water Quality and Treatment, McGraw-Hill Inc., New York, 63-156. [6] Zheng, Y. and Wang, A. (2010) Nitrate Adsorption Using Poly(dimethyl diallyl ammonium chloride)/polyacrylamide hydrogel. Journal of Chemical & Engineering Data, 55, 3494-3500.
http://dx.doi.org/10.1021/je100169r [7] Chatterjee, S. and Woo, S.H. (2009) The Removal of Nitrate from Aqueous Solutions by Chitosan Hydrogel Beads. Journal of Hazardous Materials, 164, 1012-1018.
http://dx.doi.org/10.1016/j.jhazmat.2008.09.001 [8] Romano, N. and Zeng, C. (2009) Evaluating the Newly Proposed Protocol of Incorporated Potassium in Nitrate Toxicity Experiments at Different Salinities: A Case Study with the Tiger Prawn, Penaeus monodon, Juveniles. Aquaculture, 289, 304-309.
http://dx.doi.org/10.1016/j.aquaculture.2009.01.035 [9] Ward, M.H., de Kok, T.M., Levallois, P., Brender, J., Gulis, G., Nolan, B.T. and Van Derslice, J. (2005) Workgroup Report: Drinking-Water Nitrate and Health Recent Findings and Research Needs. Environmental Health Perspectives, 113, 1607-1614.
http://dx.doi.org/10.1289/ehp.8043 [10] Lin, S.H. and Wu, C.L. (1996) Removal of Nitrogenous Compounds from Aqueous Solution by Ozonation and Ion Exchange. Water Research, 30, 1851-1857.
http://dx.doi.org/10.1016/0043-1354(95)00329-0 [11] Kostraba, T.N., Gay, E.C., Rewers, M. and Hamman, R.F. (1992) Nitrate Levels in Community Drinking Waters and Risk of IDDM, An Ecological Analysis. Diabetes Care, 15, 1505-1508.
http://dx.doi.org/10.2337/diacare.15.11.1505 [12] Wolfe, A.H. and Patz, J.A. (2002) Reactive Nitrogen and Human Health: Acute and Long-Term Implications. AMBIO: A Journal of the Human Environment, 31, 120-125.
http://dx.doi.org/10.1579/0044-7447-31.2.120 [13] US Environmental Protection Agency (2000) Drinking Water Standards and Health 614 Advisories. US Environmental Protection Agency, Office of Water, Washington DC, 822-B-00-001. [14] Schipper, L.A. and Vukovic, M.V. (2001) Five Years of Nitrate Removal, Denitrification and Carbon Dynamics in a Denitrification Wall. Water Research, 35, 3473-3477.
http://dx.doi.org/10.1016/S0043-1354(01)00052-5 [15] Hu, H.Y., Goto, N. and Fujie, K. (2001) Effect of pH on the Reduction of Nitrite in Water by Metallic Iron. Water Research, 35, 2789-2793.
http://dx.doi.org/10.1016/S0043-1354(00)00570-4 [16] Pinter, A. and Batista, J. (2006) Improvement of an Integrated Ion-Exchange/Catalytic Process for Nitrate Removal by Introducing a Two-Stage Denitrification Step. Applied Catalysis B: Environmental, 63, 150-159.
http://dx.doi.org/10.1016/j.apcatb.2005.10.006 [17] Baes, B.U., Jung, Y.H., Han, W.W. and Shin, H.S. (2002) Improved Brine Recycling during Nitrate Removal Using Ion Exchange. Water Research, 36, 3330-3340.
http://dx.doi.org/10.1016/S0043-1354(02)00012-X [18] Churchman, G.J., Gates, W.P., Theng, B.K.G. and Yuan, G. (2006) Clays and Clay Minerals for Pollution Control Handbook of Clay Science. Developments in Clay Science, 1, 625-675. [19] El ouardi, M., Qourzal, S., Alahiane, S., Sakr, F., Assabbane, A. and Douch, J. (2014) Agadir Clay Materials as a New Adsorbent to Remove Cationic and Anionic Dyes from Aqueous Solutions. International Journal of Scientific Research and Thesis, 3, 72-87. [20] Robinson, J.W. and Hsu, C.J. (1969) Spectroscopic Studies of the Chromotropic Acid-Nitrate Reaction. Analytica Chimica Acta, 44, 51-58.
http://dx.doi.org/10.1016/S0003-2670(01)81736-0 [21] West, P.W. and Lyles, G.L. (1960) A New Method for the Determination of Nitrates. Analytica Chimica Acta, 23, 227-232.
http://dx.doi.org/10.1016/S0003-2670(60)80057-8 [22] Vieira, A.P., Santana, S.A.A., Bezerra, C.W.B., Silva, H.A.S., Chaves, J.A.P., de Melo, J.C.P., da Silva Filho, E.C. and Airoldi, C. (2009) Kinetics and Thermodynamics of Textile Dye Adsorption from Aqueous Solutions Using Babassu Coconut Mesocarp. Journal of Hazardous Materials, 166, 1272-1278.
http://dx.doi.org/10.1016/j.jhazmat.2008.12.043 [23] Njoya, A., Nkoumbou, C., Grosbois, C., Njopwouo, D., Njoya, D. and Courtin-Nkoumbou, A. (2006) Genesis of Mayouom Kaolin Deposit (Western Cameroun). Applied Clay Science, 32, 125-140.
http://dx.doi.org/10.1016/j.clay.2005.11.005 [24] Dawodu, F.A. and Akpomie, K.G. (2014) Simultaneous Adsorption of Ni(II) and Mn(II) Ions from Aqueous Solution unto a Nigerian Kaolinite Clay. Journal of Materials Research and Technology, 3, 129-141. [25] Bhattacharrya, G. and Gupta, S.S. (2006) Pb(II) Uptake by Kaolinite and Montmorillonite in Aqueous Medium: Influence of Acid Activation of the Clays. Colloids and Surfaces A, 277, 191-200.
http://dx.doi.org/10.1016/j.colsurfa.2005.11.060 [26] Guo, X.L., Zengle, L. and Park, X.S. (2008) Ammonium and Potassium Anaerobically Removal for Digested Wastewater Using Natural Clinoptilolite Followed by Membrane Pretreatment. Journal of Hazardous Materials, 151, 125-133.
http://dx.doi.org/10.1016/j.jhazmat.2007.05.066 [27] Bagherifam, S., Lakzian, A., Ahmadi, S., Rahimi, F. and Halajnia, A. (2010) Uranium Removal from Aqueous Solutions by Wood Powder and Wheat Straw. Journal of Radioanalytical and Nuclear Chemistry, 283, 289-296.
http://dx.doi.org/10.1007/s10967-009-0348-4 [28] Elmoubarki, R., Mahjoubi, F.Z., Tounsadi, H., Moustadraf, J., Abdennouri, M., Zouhri, A., ElAlbani, A. and Barka, N. (2015) Adsorption of Textile Dyes on Raw and Decanted Moroccan Clays: Kinetics, Equilibrium and Thermodynamics. Water Resources and Industry, 9, 16-29.
http://dx.doi.org/10.1016/j.wri.2014.11.001 [29] Tahir, H. (2005) Comparative Trace Metal Contents in Sediments and Liquid Waste from Tanneries and Their Removal of Chromium Using Zeolite 5A. Electronic Journal of Environmental, Agricultural and Food Chemistry, 4, 23-29. [30] Moussavi, G. and Khosravi, R. (2011) The Removal of Cationic Dyes from Aqueous Solutions by Adsorption onto Pistachio Hull Waste. Chemical Engineering Research and Design, 89, 2182-2189.
http://dx.doi.org/10.1016/j.cherd.2010.11.024 [31] Vimonses, V., Lei, S., Jin, B., Chow, C.W.K. and Saint, C. (2009) Adsorption of Congo Red by Three Australian Kaolins. Applied Clay Science, 43, 465-472.
http://dx.doi.org/10.1016/j.clay.2008.11.008 [32] Islam, M. and Patel, R. (2011) Physicochemical Characterization and Adsorption Behavior of Ca/Al Chloride Hydrotalcite-Like Compound towards Removal of Nitrate. Journal of Hazardous Materials, 190, 659-668.
http://dx.doi.org/10.1016/j.jhazmat.2011.03.094 [33] Wang, Y., Gao, B.Y., Yue, W.W. and Yue, Q.Y. (2007) Adsorption Kinetics of Nitrate from Aqueous Solutions onto Modified Wheat Residue. Colloids and Surfaces A, 308, 1-5.
http://dx.doi.org/10.1016/j.colsurfa.2007.05.014 [34] Han, X., Wang, W. and Ma, X. (2011) Adsorption Characteristics of Methylene Blue onto Low Cost Biomass Material Lotus Leaf. Chemical Engineering Journal, 171, 1-8.
http://dx.doi.org/10.1016/j.cej.2011.02.067 [35] Hoda, N., Bayram, E. and Ayranci, E. (2006) Kinetic and Equilibrium Studies on the Removal of Acid Dyes from Aqueous Solutions by Adsorption onto Activated Carbon Cloth. Journal of Hazardous Materials, 137, 344-351.
http://dx.doi.org/10.1016/j.jhazmat.2006.02.009 [36] Mohan, D. and Chander, S. (2006) Single, Binary, and Multicomponent Sorption of Iron and Manganese on Lignite. Journal of Colloid and Interface Science, 299, 76-87.
http://dx.doi.org/10.1016/j.jcis.2006.02.010 [37] Seliem, M.K., Komarneni, S., Byrne, T., Cannon, F.S., Shahien, M.G., Khalil, A.A. and Abd El-Gaid, I.M. (2013) Removal of Nitrate by Synthetic Organosilicas and Organoclay: Kinetic and Isotherm Studies. Separation and Purification Technology, 110, 181-187.
http://dx.doi.org/10.1016/j.seppur.2013.03.023 [38] Gammoudi, S., Srasra, N.F. and Srasra, E. (2012) Nitrate Sorption by Organosmectites. Engineering Geology, 124, 119-129.
http://dx.doi.org/10.1016/j.enggeo.2011.10.009 [39] Yusan, S. and Akyil, S. (2008) Sorption of Uranium (VI) from Aqueous Solutions by Akaganeite. Journal of Hazardous Materials, 160, 388-395.
http://dx.doi.org/10.1016/j.jhazmat.2008.03.009 [40] Tsai, W.T., Chang, Y.M., Lai, C.W. and Lo, C.C. (2005) Adsorption of Basic Dyes in Aqueous Solution by Clay Adsorbent from Regenerated Bleaching Earth. Applied Clay Science, 29, 149-154.
http://dx.doi.org/10.1016/j.clay.2004.10.004
[1] Jeong, J.Y., Kim, H.K., Kim, J.H. and Park, J.Y. (2012) Electrochemical Removal of Nitrate Using ZVI Packed Bed Bipolar Electrolytic Cell. Chemosphere, 89, 172-178.
http://dx.doi.org/10.1016/j.chemosphere.2012.05.104 [2] Zhou, M., Fu, W., Gu, H. and Lei, L. (2007) Nitrate Removal from Groundwater by a Novel Three-Dimensional Electrode Biofilm Reactor. Electrochimica Acta, 52, 6052-6059.
http://dx.doi.org/10.1016/j.electacta.2007.03.064 [3] Thomson, T.S. (2001) Nitrate Concentration in Private Rural Drinking Water Supplies in Saskatchewan Canada. Bulletin of Environmental Contamination and Toxicology, 66, 64-70.
http://dx.doi.org/10.1007/s001280000206 [4] Majumdar, D. and Gupta, N. (2000) Nitrate Pollution of Groundwater and Associated Human Health Disorders. Indian Journal of Environmental Health, 42, 28-39. [5] Tate, C.H. and Arnold, K.F. (1990) Health and Aesthetic Aspects of Water Quality. In: Pontius, F.W., Ed., Water Quality and Treatment, McGraw-Hill Inc., New York, 63-156. [6] Zheng, Y. and Wang, A. (2010) Nitrate Adsorption Using Poly(dimethyl diallyl ammonium chloride)/polyacrylamide hydrogel. Journal of Chemical & Engineering Data, 55, 3494-3500.
http://dx.doi.org/10.1021/je100169r [7] Chatterjee, S. and Woo, S.H. (2009) The Removal of Nitrate from Aqueous Solutions by Chitosan Hydrogel Beads. Journal of Hazardous Materials, 164, 1012-1018.
http://dx.doi.org/10.1016/j.jhazmat.2008.09.001 [8] Romano, N. and Zeng, C. (2009) Evaluating the Newly Proposed Protocol of Incorporated Potassium in Nitrate Toxicity Experiments at Different Salinities: A Case Study with the Tiger Prawn, Penaeus monodon, Juveniles. Aquaculture, 289, 304-309.
http://dx.doi.org/10.1016/j.aquaculture.2009.01.035 [9] Ward, M.H., de Kok, T.M., Levallois, P., Brender, J., Gulis, G., Nolan, B.T. and Van Derslice, J. (2005) Workgroup Report: Drinking-Water Nitrate and Health Recent Findings and Research Needs. Environmental Health Perspectives, 113, 1607-1614.
http://dx.doi.org/10.1289/ehp.8043 [10] Lin, S.H. and Wu, C.L. (1996) Removal of Nitrogenous Compounds from Aqueous Solution by Ozonation and Ion Exchange. Water Research, 30, 1851-1857.
http://dx.doi.org/10.1016/0043-1354(95)00329-0 [11] Kostraba, T.N., Gay, E.C., Rewers, M. and Hamman, R.F. (1992) Nitrate Levels in Community Drinking Waters and Risk of IDDM, An Ecological Analysis. Diabetes Care, 15, 1505-1508.
http://dx.doi.org/10.2337/diacare.15.11.1505 [12] Wolfe, A.H. and Patz, J.A. (2002) Reactive Nitrogen and Human Health: Acute and Long-Term Implications. AMBIO: A Journal of the Human Environment, 31, 120-125.
http://dx.doi.org/10.1579/0044-7447-31.2.120 [13] US Environmental Protection Agency (2000) Drinking Water Standards and Health 614 Advisories. US Environmental Protection Agency, Office of Water, Washington DC, 822-B-00-001. [14] Schipper, L.A. and Vukovic, M.V. (2001) Five Years of Nitrate Removal, Denitrification and Carbon Dynamics in a Denitrification Wall. Water Research, 35, 3473-3477.
http://dx.doi.org/10.1016/S0043-1354(01)00052-5 [15] Hu, H.Y., Goto, N. and Fujie, K. (2001) Effect of pH on the Reduction of Nitrite in Water by Metallic Iron. Water Research, 35, 2789-2793.
http://dx.doi.org/10.1016/S0043-1354(00)00570-4 [16] Pinter, A. and Batista, J. (2006) Improvement of an Integrated Ion-Exchange/Catalytic Process for Nitrate Removal by Introducing a Two-Stage Denitrification Step. Applied Catalysis B: Environmental, 63, 150-159.
http://dx.doi.org/10.1016/j.apcatb.2005.10.006 [17] Baes, B.U., Jung, Y.H., Han, W.W. and Shin, H.S. (2002) Improved Brine Recycling during Nitrate Removal Using Ion Exchange. Water Research, 36, 3330-3340.
http://dx.doi.org/10.1016/S0043-1354(02)00012-X [18] Churchman, G.J., Gates, W.P., Theng, B.K.G. and Yuan, G. (2006) Clays and Clay Minerals for Pollution Control Handbook of Clay Science. Developments in Clay Science, 1, 625-675. [19] El ouardi, M., Qourzal, S., Alahiane, S., Sakr, F., Assabbane, A. and Douch, J. (2014) Agadir Clay Materials as a New Adsorbent to Remove Cationic and Anionic Dyes from Aqueous Solutions. International Journal of Scientific Research and Thesis, 3, 72-87. [20] Robinson, J.W. and Hsu, C.J. (1969) Spectroscopic Studies of the Chromotropic Acid-Nitrate Reaction. Analytica Chimica Acta, 44, 51-58.
http://dx.doi.org/10.1016/S0003-2670(01)81736-0 [21] West, P.W. and Lyles, G.L. (1960) A New Method for the Determination of Nitrates. Analytica Chimica Acta, 23, 227-232.
http://dx.doi.org/10.1016/S0003-2670(60)80057-8 [22] Vieira, A.P., Santana, S.A.A., Bezerra, C.W.B., Silva, H.A.S., Chaves, J.A.P., de Melo, J.C.P., da Silva Filho, E.C. and Airoldi, C. (2009) Kinetics and Thermodynamics of Textile Dye Adsorption from Aqueous Solutions Using Babassu Coconut Mesocarp. Journal of Hazardous Materials, 166, 1272-1278.
http://dx.doi.org/10.1016/j.jhazmat.2008.12.043 [23] Njoya, A., Nkoumbou, C., Grosbois, C., Njopwouo, D., Njoya, D. and Courtin-Nkoumbou, A. (2006) Genesis of Mayouom Kaolin Deposit (Western Cameroun). Applied Clay Science, 32, 125-140.
http://dx.doi.org/10.1016/j.clay.2005.11.005 [24] Dawodu, F.A. and Akpomie, K.G. (2014) Simultaneous Adsorption of Ni(II) and Mn(II) Ions from Aqueous Solution unto a Nigerian Kaolinite Clay. Journal of Materials Research and Technology, 3, 129-141. [25] Bhattacharrya, G. and Gupta, S.S. (2006) Pb(II) Uptake by Kaolinite and Montmorillonite in Aqueous Medium: Influence of Acid Activation of the Clays. Colloids and Surfaces A, 277, 191-200.
http://dx.doi.org/10.1016/j.colsurfa.2005.11.060 [26] Guo, X.L., Zengle, L. and Park, X.S. (2008) Ammonium and Potassium Anaerobically Removal for Digested Wastewater Using Natural Clinoptilolite Followed by Membrane Pretreatment. Journal of Hazardous Materials, 151, 125-133.
http://dx.doi.org/10.1016/j.jhazmat.2007.05.066 [27] Bagherifam, S., Lakzian, A., Ahmadi, S., Rahimi, F. and Halajnia, A. (2010) Uranium Removal from Aqueous Solutions by Wood Powder and Wheat Straw. Journal of Radioanalytical and Nuclear Chemistry, 283, 289-296.
http://dx.doi.org/10.1007/s10967-009-0348-4 [28] Elmoubarki, R., Mahjoubi, F.Z., Tounsadi, H., Moustadraf, J., Abdennouri, M., Zouhri, A., ElAlbani, A. and Barka, N. (2015) Adsorption of Textile Dyes on Raw and Decanted Moroccan Clays: Kinetics, Equilibrium and Thermodynamics. Water Resources and Industry, 9, 16-29.
http://dx.doi.org/10.1016/j.wri.2014.11.001 [29] Tahir, H. (2005) Comparative Trace Metal Contents in Sediments and Liquid Waste from Tanneries and Their Removal of Chromium Using Zeolite 5A. Electronic Journal of Environmental, Agricultural and Food Chemistry, 4, 23-29. [30] Moussavi, G. and Khosravi, R. (2011) The Removal of Cationic Dyes from Aqueous Solutions by Adsorption onto Pistachio Hull Waste. Chemical Engineering Research and Design, 89, 2182-2189.
http://dx.doi.org/10.1016/j.cherd.2010.11.024 [31] Vimonses, V., Lei, S., Jin, B., Chow, C.W.K. and Saint, C. (2009) Adsorption of Congo Red by Three Australian Kaolins. Applied Clay Science, 43, 465-472.
http://dx.doi.org/10.1016/j.clay.2008.11.008 [32] Islam, M. and Patel, R. (2011) Physicochemical Characterization and Adsorption Behavior of Ca/Al Chloride Hydrotalcite-Like Compound towards Removal of Nitrate. Journal of Hazardous Materials, 190, 659-668.
http://dx.doi.org/10.1016/j.jhazmat.2011.03.094 [33] Wang, Y., Gao, B.Y., Yue, W.W. and Yue, Q.Y. (2007) Adsorption Kinetics of Nitrate from Aqueous Solutions onto Modified Wheat Residue. Colloids and Surfaces A, 308, 1-5.
http://dx.doi.org/10.1016/j.colsurfa.2007.05.014 [34] Han, X., Wang, W. and Ma, X. (2011) Adsorption Characteristics of Methylene Blue onto Low Cost Biomass Material Lotus Leaf. Chemical Engineering Journal, 171, 1-8.
http://dx.doi.org/10.1016/j.cej.2011.02.067 [35] Hoda, N., Bayram, E. and Ayranci, E. (2006) Kinetic and Equilibrium Studies on the Removal of Acid Dyes from Aqueous Solutions by Adsorption onto Activated Carbon Cloth. Journal of Hazardous Materials, 137, 344-351.
http://dx.doi.org/10.1016/j.jhazmat.2006.02.009 [36] Mohan, D. and Chander, S. (2006) Single, Binary, and Multicomponent Sorption of Iron and Manganese on Lignite. Journal of Colloid and Interface Science, 299, 76-87.
http://dx.doi.org/10.1016/j.jcis.2006.02.010 [37] Seliem, M.K., Komarneni, S., Byrne, T., Cannon, F.S., Shahien, M.G., Khalil, A.A. and Abd El-Gaid, I.M. (2013) Removal of Nitrate by Synthetic Organosilicas and Organoclay: Kinetic and Isotherm Studies. Separation and Purification Technology, 110, 181-187.
http://dx.doi.org/10.1016/j.seppur.2013.03.023 [38] Gammoudi, S., Srasra, N.F. and Srasra, E. (2012) Nitrate Sorption by Organosmectites. Engineering Geology, 124, 119-129.
http://dx.doi.org/10.1016/j.enggeo.2011.10.009 [39] Yusan, S. and Akyil, S. (2008) Sorption of Uranium (VI) from Aqueous Solutions by Akaganeite. Journal of Hazardous Materials, 160, 388-395.
http://dx.doi.org/10.1016/j.jhazmat.2008.03.009 [40] Tsai, W.T., Chang, Y.M., Lai, C.W. and Lo, C.C. (2005) Adsorption of Basic Dyes in Aqueous Solution by Clay Adsorbent from Regenerated Bleaching Earth. Applied Clay Science, 29, 149-154.
http://dx.doi.org/10.1016/j.clay.2004.10.004