Personal Research Database

Full Text: 2011\J Haz Mat186, 150.pdf

Abstract: Polypyrrole (PPy)/Fe₃O₄ magnetic nanocomposite as a novel adsorbent was prepared via in-situ polymerization of pyrrole (Py) monomer using FeCl3 oxidant in aqueous medium in which Fe₃O₄ nanoparticles were suspended. The adsorbent was characterized by Attenuated Total Reflectance Fourier transform infrared spectroscope (ATR-FTIR), Brunauer-Emmet-Teller (BET) method, field emission scanning electron microscope (FE-SEM), high resolution transmission electron microscope (HR-TEM). X-ray photoelectron spectroscope (XPS) and X-ray diffraction (XRD). Magnetic property of the adsorbent was measured by electron spin resonance (ESR). Subsequently, the ability of the adsorbent to remove fluoride ions from aqueous solution was demonstrated in a batch sorption mode. Results reveal that the adsorption is rapid and that the adsorbent has high affinity for fluoride, which depends on temperature, solution pH and adsorbent dose. From equilibrium modelling, the equilibrium data is well described by Freundlich and Langmuir-Freundlich isotherms while the adsorption kinetics is described by the pseudo-second-order model. Thermodynamic parameters confirm the spontaneity and endothermic nature of the fluoride adsorption. Meanwhile, the fluoride adsorption proceeds by an ion exchange mechanism. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption, Behaviors, Carbon Nanotube Composites, Conducting Polypyrrole, Defluoridation, Dialysis, Electrical-Properties, Equilibrium, Equilibrium, Fluoride, Freundlich, Kinetics, Magnetic, Magnetic Nanocomposite, Nanoparticles, pH, Polypyrrole, Removal, Sorption, Thermodynamic, Water, XPS

? Panneerselvam, P., Morad, N. and Tan, K.A. (2011), Magnetic nanoparticle (Fe₃O₄) impregnated onto tea waste for the removal of nickel(II) from aqueous solution. Journal of Hazardous Materials, 186 (1), 160-168.

Full Text: 2011\J Haz Mat186, 160.pdf

Abstract: The removal of Ni(II) from aqueous solution by magnetic nanoparticles prepared and impregnated onto tea waste (Fe(3)O(4)-TW) from agriculture biomass was investigated. Magnetic nanoparticles (Fe(3)O(4)) were prepared by chemical precipitation of a Fe(2+) and Fe(3+) salts from aqueous solution by ammonia solution. These magnetic nanoparticles of the adsorbent Fe(3)O(4) were characterized by surface area (BET), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Fourier Transform-Infrared Spectroscopy (FT-IR). The effects of various parameters, such as contact time, pH, concentration, adsorbent dosage and temperature were studied. The kinetics followed is first order in nature, and the value of rate constant was found to be 1.90 x 10(-2) min(-1) at 100 mg L(-1) and 303 K. Removal efficiency decreases from 99 to 87% by increasing the concentration of Ni(II) in solution from 50 to 100 mg L(-1). It was found that the adsorption of Ni(II) increases by increasing temperature from 303 to 323 K and the process is endothermic in nature. The adsorption isotherm data were fitted to Langmuir and Freundlich equation, and the Langmuir adsorption capacity, IT, was found to be (38.3).mg g(-1). The results also revealed that nanoparticle impregnated onto tea waste from agriculture biomass, can be an attractive option for metal removal from industrial effluent. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption Isotherm, Agricultural Waste, Bakers-Yeast, Capacity, First Order, Fixed-Bed, Fly-Ash, FTIR, Industry Waste, Iron-Oxide Nanoparticles, Isotherm, Kinetics, Magnetic Nanoparticle, Magnetic Nanoparticles, Metal, Nano-Adsorbent, Ni(II) Ions, Nickel(II), pH, Precipitation, Rate Constant, Removal, Tea Waste, Thermodynamics, Transmission, Ulothrix-Zonata

? Liu, Y., Liu, Z.C., Gao, J., Dai, J.D., Han, J.A., Wang, Y., Xie, J.M. and Yan, Y.S. (2011), Selective adsorption behavior of Pb(II) by mesoporous silica SBA-15-supported Pb(II)-imprinted polymer based on surface molecularly imprinting technique. Journal of Hazardous Materials, 186 (1), 197-205.

Full Text: 2011\J Haz Mat186, 197.pdf

Abstract: In this study, a new Pb(II) ion-imprinted polymer (Pb(II)-IIP), which can be used for selective adsorption of Pb(II) from aqueous solutions, was successfully prepared based on the supported material of ordered mesoporous silica SBA-15 with the help of surface molecular imprinting technology. The prepared polymer was characterized by Fourier transmission infrared spectrometry, X-ray diffraction, transmission electron microscope and nitrogen adsorption-desorption isotherm. The results showed that the synthesized polymer possessed high ordered mesoporous structure. The adsorption behavior of the adsorbents for Pb(II) was investigated using batch experiments. The Pb(II)-IIP showed fast kinetics, high selectivity and satisfied adsorption capacity for adsorption of Pb(II). Under the optimum experimental condition, Pb(II) adsorption process over Pb(II)-IIP follows pseudo-second-order reaction kinetics and follows the Langmuir adsorption isotherm. In addition, the thermodynamic parameters calculated from the adsorption data suggested that the adsorption of Pb(II) onto Pb(II)-IIP was a spontaneous and exothermic nature of the process. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Isotherm, Aqueous-Solutions, Chitosan, Hybrid Materials, Isotherm, Kinetics, Langmuir, Lead, Metal-Ions, Pb(II), Removal, SBA-15, Selective, Selective Adsorption, Solid-Phase Extraction, Sorption, Surface Ion-Imprinted, Thermodynamic, Thermodynamic Parameters, Waste

? Pillewan, P., Mukherjee, S., Roychowdhury, T., Das, S., Bansiwal, A. and Rayalu, S. (2011), Removal of As(III) and As(V) from water by copper oxide incorporated mesoporous alumina. Journal of Hazardous Materials, 186 (1), 367-375.

Full Text: 2011\J Haz Mat186, 367.pdf

Abstract: In the present manuscript a new adsorbent namely copper oxide incorporated mesoporous alumina (COIMA) for removal of arsenic from water is reported. The COIMA was prepared by treating mesoporous alumina with copper sulphate solution followed by calcination at 450ºC in the presence of air. Various adsorption isotherm and kinetic parameters were computed using batch adsorption studies to determine the adsorption capacity for As(III) and As(V) and to understand the mechanism of adsorption. It was observed that incorporation of copper oxide improves the adsorption capacity of unmodified alumina from 0.92 to 2.16 mg g^-1 for As(III) and from 0.84 to 2.02 mg g^-1 for As(V). The results revealed that the adsorption follows Langmuir isotherm and pseudo-second-order kinetic models for both As(III) and As(V). The material is capable of simultaneously removing As(III) and As(V) with removal efficiencies of more than 95% for both As(III) and As(V). Assessment of the water quality before and after treatment with COIMA also confirmed that the there is no leaching of copper and other parameters were also within permissible limits of Indian drinking water standard indicating that the COIMA can be used for treatment of arsenic contaminated drinking water. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption Isotherm, Alumina, Arsenic Removal, Arsenic Removal, Contamination, Copper Oxide, Drinking-Water, Groundwater, India, Isotherm, Kinetic, Langmuir, Langmuir Isotherm, Removal, Speciation

? Li, X.N., Zhao, H.M., Quan, X., Chen, S.O., Zhang, Y.B. and Yu, H.T. (2011), Adsorption of ionizable organic contaminants on multi-walled carbon nanotubes with different oxygen contents. Journal of Hazardous Materials, 186 (1), 407-415.

Full Text: 2011\J Haz Mat186, 407.pdf

Abstract: Multi-walled carbon nanotubes (MWNTs), which are considered to be promising candidates for the adsorption of toxic organics, are released into aqueous environment with their increasing production and application. In this study, the adsorption behaviors of five structurally related ionizable organic contaminants namely perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorooctanesulfonamide (PFOSA), 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-n-nonylphenol (4-NP) onto MWNTs with different oxygen contents (3.84-22.85%) were investigated. The adsorption kinetics was investigated and simulated with pseudo-second-order model. The adsorption isotherms were found to be fitted with Freundlich model and influenced by both the properties of organic chemicals and the oxygen contents of MWNTs. As adsorption capacity decreases dramatically with the increasing of oxygen contents. the MWNTs with the lowest oxygen contents possess the highest adsorption capacity among four MWNTs. For the MWNTs with the oxygen contents of 3.84%, the adsorption affinity related with hydrophobic interaction and pi-electron polarizability decreased in the order of 4-NP > PFOSA > PFOS > 2,4-D > PFOA. Furthermore, the adsorption characters of five contaminants were affected by solution pH and solute pK(a) considering electrostatic repulse force and hydrogen bonding, which showed the adsorption of MWNTs with lower oxygen content is much sensitive to solution chemistry. (c) 2010 Elsevier B.V. All rights reserved.

Keywords: 2,4-D, Activated Carbon, Adsorption, Aqueous-Solutions, Chemicals, Colloidal Stability, Freundlich, Ionizable Organic Contaminant, Kinetics, Multi-Walled Carbon Nanotubes, Perfluorooctane Sulfonate, pH, Removal, Sorption, Surface Oxides, Thermodynamics

? Boparai, H.K., Joseph, M. and O’Carroll, D.M. (2011), Kinetics and thermodynamics of cadmium ion removal by adsorption onto nano zerovalent iron particles. Journal of Hazardous Materials, 186 (1), 458-465.

Full Text: 2011\J Haz Mat186, 458.pdf

Abstract: Nano zerovalent iron (nZVI) is an effective adsorbent for removing various organic and inorganic contaminants. In this study. nZVI particles were used to investigate the removal of Cd²⁺ in the concentration ;range of 25-450 mgL^-1. The effect of temperature on kinetics and equilibrium of cadmium sorption on nZVI particles was thoroughly examined. Consistent with an endothermic reaction, an increase in the temperature resulted in increasing cadmium adsorption rate. The adsorption kinetics well fitted using a pseudo second-order kinetic model. The calculated activation energy for adsorption was 54.8 kJ mol^-1, indicating the adsorption process to be chemisorption. The intraparticle diffusion model described that the intraparticle diffusion was not the only rate-limiting step. The adsorption isotherm data could be well described by the Langmuir as well as Temkin equations. The maximum adsorption capacity of nZVI for Cd²⁺ was found to be 769.2 mg g^-1 at 297K. Thermodynamic parameters (i.e., change in the free energy (ΔGº), the enthalpy (ΔHº), and the entropy (ΔSº)) were also evaluated. The overall adsorption process was endothermic and spontaneous in nature. EDX analysis indicated the presence of cadmium ions on the nZVI surface. These results suggest that nZVI could be employed as an efficient adsorbent for the removal of cadmium from contaminated water sources. (c) 2010 Elsevier B.V. All rights reserved.

Keywords: Acid, Adsorption, Adsorption Isotherm, Aqueous-Solutions, Behavior, Cadmium, Carbon, Equilibrium, Isotherm, Isotherm Equation, Kinetic, Kinetic Model, Kinetics, Langmuir, Models, Nano, Nanoparticles, Sorption, Spectroscopy, Thermodynamic, Thermodynamics, Zero-Valent Iron, Zerovalent Iron

? Phuengprasop, T., Sittiwong, J. and Unob, F. (2011), Removal of heavy metal ions by iron oxide coated sewage sludge. Journal of Hazardous Materials, 186 (1), 502-507.

Full Text: 2011\J Haz Mat186, 502.pdf

Abstract: The municipal sewage sludge was modified with iron oxide employed in metal ions removal. The surface modification method was proposed and the effect of parameters in the preparation was studied. The iron oxide coated sludge had higher surface area, pore volume and iron content, compared to uncoated sludge. The suitable conditions for removal of Cu(II), Cd(II), Ni(II) and Pb(II) ions from solutions were investigated using batch method. The suitable pH value in the extraction was 7 for adsorption of Cd(II) and Ni(II), 6 for Cu(II) and 5 for Pb(II) ions. The presence of NaNO₃, Ca(NO₃)₂ and Na₂SO₄ in metal solution in the concentration of 0.01 M and 0.50 M could reduce the removal efficiency. The adsorption isotherms for the adsorption of the metal ions were defined by Langmuir relation. The maximum adsorption capacity of the iron oxide coated sludge for Cu(II), Cd(II), Ni(II) and Pb(II) was 17.3, 14.7, 7.8 and 42.4 mg g^-1, respectively. The adsorption kinetics for every metal ions followed pseudo-second order model. The metal removal from wastewater by iron oxide coated sludge was also demonstrated. (c) 2010 Elsevier B.V. All rights reserved.

Keywords: Activated-Sludge, Adsorbent, Adsorption, Adsorption, Aqueous-Solution, Arsenic Removal, As(V) Removal, Carbon, Cd(II), Cu(II), Fixed-Bed Column, Iron Oxide, Kinetics, Langmuir, Magnetic Composites, Metal Ions, Pb(II), pH, Removal, Sludge, Waste-Water, Wastewater

? Saikia, J., Saha, B. and Das, G. (2011), Efficient removal of chromate and arsenate from individual and mixed system by malachite nanoparticles. Journal of Hazardous Materials, 186 (1), 575-582.

Full Text: 2011\J Haz Mat186, 575.pdf

Abstract: Malachite nanoparticles of 100-150 nm have been efficiently and for the first time used as an adsorbent for the removal of toxic arsenate and chromate. We report a high adsorption capacity for chromate and arsenate on malachite nanoparticle from both individual and mixed solution in pH similar to 4-5. However, the adsorption efficiency decreases with the increase of solution pH. Batch studies revealed that initial pH, temperature, malachite nanoparticles dose and initial concentration of chromate and arsenate were important parameters for the adsorption process. Thermodynamic analysis showed that adsorption of chromate and arsenate on malachite nanoparticles is endothermic and spontaneous. The adsorption of these anions has also been investigated quantitatively with the help of adsorption kinetics, isotherm, and selectivity coefficient (K) analysis. The adsorption data for both chromate and arsenate were fitted well in Langmuir isotherm and preferentially followed the second order kinetics. The binding affinity of chromate is found to be slightly higher than arsenate in a competitive adsorption process which leads to the comparatively higher adsorption of chromate on malachite nanoparticles surface. (c) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorbent, Adsorbents, Adsorption, Adsorption Kinetics, Adsorption Selectivity, Analysis, Anions, Arsenate, Batch, Bovine Serum-Albumin, Capacity, Chromate, Competitive Adsorption, Controlled Adsorption, Cr(VI), Hexavalent Chromium, Isotherm, Isotherms, Kinetics, Langmuir Isotherm, Magnetic Beads, Malachite Nanoparticles, pH, Removal, Thermodynamic, Thermodynamics, Waste-Water

? Zong, G.X., Chen, H., Qu, R.J., Wang, C.H. and Ji, N.Y. (2011), Synthesis of polyacrylonitrile-grafted cross-linked N-chlorosulfonamidated polystyrene via surface-initiated ARGET ATRP, and use of the resin in mercury removal after modification. Journal of Hazardous Materials, 186 (1), 614-621.

Full Text: 2011\J Haz Mat186, 614.pdf

Abstract: A novel method of surface modification was developed via iron (III)-mediated atom transfer radical polymerization, with activators regenerated by electron transfer (ARGET ATRP) on the surfaces of polystyrene resin-supported N-chlorosulfonamide groups. The well-defined polyacrylonitrile (PAN) was grafted onto the surfaces of the polystyrene (PS). The graft reaction exhibited first-order kinetics with respect to the polymerization time in the low-monomer-conversion stage. The cyano group of PAN-g-PS was modified by NH(2)OH center dot HCl to yield amidoxime (AO) groups. The AO groups had been demonstrated to be an efficient Hg-specific sorbent, which can remove Hg(2+) from solutions. No interference arose from common metal ions, such as Pd(2+), Ag(+), and Cu(2+). Three adsorption-desorption cycles demonstrated that this resin is suitable for reuse without any considerable change in adsorption capacity. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Acrylonitrile, Adsorption, Adsorption-Desorption, Amidoxime, Amidoxime Adsorbents, Capacity, Electron-Transfer, First Order, Heavy-Metals, Hyperbranched Polymer, Ions, Iron, Kinetics, Mercury, Metal, Metal Ions, Metal-Ions, Modification, Modified, Multiwalled Carbon Nanotubes, Reducing Agent, Removal, Reuse, Silica Nanoparticles, Sorbent, Surface-Initiated Arget Atrp, Synthesis, Transfer Radical Polymerization, Uranium Recovery

? Idris, A., Hassan, N., Rashid, R. and Ngomsik, A.F. (2011), Kinetic and regeneration studies of photocatalytic magnetic separable beads for chromium(VI) reduction under sunlight. Journal of Hazardous Materials, 186 (1), 629-635.

Full Text: 2011\J Haz Mat186, 629.pdf

Abstract: Physical adsorption and photocatalytic reduction of Cr(VI) in magnetic separable beads were investigated. In order to elucidate the kinetics of photocatalytic process, operating parameters such as catalyst dosage and the initial concentration were examined in detail. It was observed that the reduction rate of Cr(VI) increased with an increase in the catalyst loading, as this translated into an increase in the number of available active sites. Critical scrutiny of the percentage of the initial reduction rate versus time at various initial concentration of Cr(VI) revealed that the rate of substrate conversion decreased as the initial concentration increased. The kinetic analysis of the photoreduction showed that the removal of Cr(VI) satisfactory obeyed the pseudo first-order kinetic according to the Langmuir-Hinshelwood (L-H) model and the absorption of Cr(VI) on the magnetic beads surfaces was the controlling step in the entire reduction process. Furthermore, desorption experiments by elution of the loaded gels with sodium hydroxide indicated that the magnetic photocatalyst beads could be reused without significant losses of their initial properties even after 3 adsorption-desorption cycles. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Adsorption, Adsorption-Desorption, Analysis, Chromium, Cr(VI), Critical, Degradation, Desorption, First Order, Hexavalent Chromium, Kinetic, Kinetics, Langmuir-Hinshelwood Model, Maghemite, Maghemite Nanoparticles, Magnetic Beads, Magnetic Nanoparticles, Model, Orange, Photocatalyst, Pseudo-First-Order, Recovery, Reduction, Regeneration, Removal, Titania, Waste-Water

? Yang, S.Y., Yang, X., Shao, X.T., Niu, R. and Wang, L.L. (2011), Activated carbon catalyzed persulfate oxidation of Azo dye acid orange 7 at ambient temperature. Journal of Hazardous Materials, 186 (1), 659-666.

Full Text: 2011\J Haz Mat186, 659.pdf

Abstract: Persulfate (PS) oxidative degradation of azo dye acid orange 7 (AO7) in an aqueous solution was studied in the presence of suspended granular activated carbon (GAC) at ambient temperature (e.g., 25 degrees C). It was observed that there existed a remarkable synergistic effect in the GAC/PS combined system. Higher PS concentration and GAC dosage resulted in higher AO7 degrading rates. Near-neutral was the optimal initial pH. Adsorption had an adverse effect on AO7 degradation. AO7 had not only a good decolorization, but a good mineralization. The decomposition of PS followed a first-order kinetics behavior both in the presence and in the absence of AO7. Radical mechanism was studied and three radical scavengers (methanol (MA), tert-butanol (TBA), phenol) were used to determine the kind of major active species taking part in the degradation of AO7 and the location of degradation reaction. It was assumed that the degradation of AO7 did not occur in the liquid phase, but in the porous bulk and boundary layer on the external surface of GAC. SO(4)(-center dot) or HO(center dot), generated on or near the surface of GAC, played a major role in the AO7 degradation. Finally, the recovery performance of GAC was studied through the GAC reuse experiments. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Acid Orange 7, Activated Carbon, Adsorption, Aqueous-Solution, Azo Dye, Behavior, Butyl Ether MTBE, Degradation, Fentons Reagent, First Order, GAC, Granular Activated Carbon, Hydrogen-Peroxide, Kinetics, Mechanism, Organic Contaminants, Oxidation, Persulfate Oxidation, Ph, Phenol, Radical Mechanism, Rate Constants, Recovery, Reuse, TBA, Water, Wet Peroxide Oxidation

? Bairagi, H., Khan, M.M.R., Ray, L. and Guha, A.K. (2011), Adsorption profile of lead on Aspergillus versicolor: A mechanistic probing. Journal of Hazardous Materials, 186 (1), 756-764.

Full Text: 2011\J Haz Mat186, 756.pdf

Abstract: The adsorption of lead on Aspergillus versicolor biomass (AVB) has been investigated in aqueous solution with special reference to binding mechanism in order to explore the possibilities of the biomass to address environmental pollution. AVB, being the most potent of all the fungal biomasses tested, has been successfully employed for reducing the lead content of the effluents of battery industries to permissible limit (1.0 mg L^-1) before discharging into waterbodies. The results establish that 1.0 g of the biomass adsorbs 45.0 mg of lead and the adsorption process is found to depend on the pH of the solution with an optimum at pH 5.0. The rate of adsorption of lead by AVB is very fast initially attaining equilibrium within 3 h following pseudo second order rate model. The adsorption process can better be described by Redlich-Peterson isotherm model compared to other ones tested. Scanning electron micrograph demonstrates conspicuous changes in the surface morphology of the biomass as a result of lead adsorption. Zeta potential values, chemical modification of the functional groups and Fourier transform infrared spectroscopy reveal that binding of lead on AVB occurs through complexation as well as electrostatic interaction. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Activated Carbons, Adsorption, Aqueous-Solution, Aspergillus Versicolor, Bacterial Surfaces, Binding Mechanism, Biosorption, Chemical Modification, Equilibrium, Heavy-Metals, Isotherm, Lead, Metal-Ions, pH, Rhizopus-arrhizus, Saccharomyces-cerevisiae, Thermodynamic Parameters

? Arulkumar, M., Sathishkumar, P. and Palvannan, T. (2011), Optimization of Orange G dye adsorption by activated carbon of Thespesia populnea pods using response surface methodology. Journal of Hazardous Materials, 186 (1), 827-834.

Full Text: 2011\J Haz Mat186, 827.pdf

Abstract: Thespesia populnea is a large tree found in the tropical regions and coastal forests of India. Its pods were used as a raw material for the preparation of activated carbon. The prepared activated carbon was used for the adsorptive removal of Orange G dye from aqueous system. The effects of various parameters such as agitation time, initial dye concentration and adsorbent dosage were studied using response surface methodology (RSM). RSM results show that 0.54 g of activated carbon was required for the maximum adsorption of Orange G dye (17.6 mg L^-1) within a time period of 4.03 h. Adsorption data were modeled using Freundlich and Langmuir adsorption isotherms. The adsorption of Orange G dye by activated carbon obeyed both Fruendlich and Langmuir isotherm. Adsorption kinetic data were tested using pseudo-zero, first, second-order and intraparticle diffusion models. Kinetic studies revealed that the adsorption followed pseudo-second-order reaction with regard to the intraparticle diffusion. FTIR spectral result indicated all the functional group except primary amines (3417 cm^-1) and C=N (1618 cm^-1) were involved in the adsorption process. XRD data showed that Orange G dye adsorbed activated carbon might not induce the bulk phase changes. SEM results showed that the surface of the activated carbon was turned from dark to light color after dye adsorption. (C) 2010 Elsevier B.V. All rights reserved.

Keywords: Activated Carbon, Adsorption, Adsorption Isotherm, Adsorption Kinetic, Agricultural Waste, Aqueous-Solutions, Basic Dye, Coconut Husk, Dye, Equilibrium, Freundlich, FTIR, Industry Waste, Isotherm, Kinetic, Kinetics, Langmuir, Langmuir Isotherm, Methylene-Blue, Orange G Dye, Physicochemical Characterization, Removal, Sawdust, Thespesia populnea Pods

? Chen, N., Zhang, Z.Y., Feng, C.P., Zhu, D.R., Yang, Y.N. and Sugiura, N. (2011), Preparation and characterization of porous granular ceramic containing dispersed aluminum and iron oxides as adsorbents for fluoride removal from aqueous solution. Journal of Hazardous Materials,