Personal Research Database

Full Text: J\J Haz Mat92, 161.pdf

Abstract: The adsorption of mercury from aqueous solutions and chlor-alkali industry effluent on steam activated and sulphurised steam activated carbons prepared from bagasse pith have been studied comparatively. The uptake of mercury(II) (Hg(II)) was maximum by steam activated carbon in presence of SO₂ and H₂S (SA-SO₂-H₂S-C) followed by steam activated carbon in presence of SO₂ (SA-SO₂-C), steam activated carbon in presence of H₂S (SA-H₂S-C) and steam activated carbon (SA-C) at the same concentration, pH and temperature of the solution. Adsorption experiments demonstrate that the adsorption process corresponds to the pseudo-second-order kinetic model and equilibrium results correspond to the Langmuir adsorption isotherm. Kinetic parameters as a function of initial concentration, for all adsorbents were calculated. Batch studies indicated that the optimum pH range for the adsorption of Hg(II) on sulphurised carbons was between 4 and 9 and for sulphur free carbon was between 6 and 9 at 30degreesC. The adsorptive behaviour of the activated carbons is explained on the basis of their chemical nature and porous texture. Decrease in ionic strength and increase in temperature of the solution has been found to improve the uptake of Hg(H). Synthetic and chlor-alkali industrial wastewaters were also treated by sulphurised activated carbons to demonstrate their efficiencies in removing Hg(H) from wastewaters. Some feasibility experiments have been carried out with a view to recover the adsorbed Hg(II) and regenerate the spent activated carbons using 0.2 M HCl solution. The data obtained point towards viable adsorbents, which are both effective as well as economically attractive for Hg(II) removal from wastewaters. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Activated Carbon, Activated Carbons, Adsorbents, Adsorption, Adsorption Isotherm, Aqueous Solutions, Bagasse, Bagasse Pith, Behaviour, Carbon, Chemical, Concentration, Data, Equilibrium, Equilibrium Studies, Experiments, Feasibility, Function, Hg(II), Ionic Strength, Isotherm, Kinetic, Kinetic Model, Kinetic Parameters, Kinetics, Langmuir, Langmuir Adsorption Isotherm, Mercury, Mercury Removal, Mercury(II), Model, pH, Pith, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Kinetic Model, Regeneration, Removal, SO₂, Solution, Solutions, Strength, Sulphurised Activated Carbon, Synthetic and Chlor-Alkali Industrial Wastewaters, Temperature, Uptake, Wastewaters

Rengaraj, S., Yeon, K.H., Kang, S.Y., Lee, J.U., Kim, K.W. and Moon, S.H. (2002), Studies on adsorptive removal of Co(II), Cr(III) and Ni(II) by IRN77 cation-exchange resin. Journal of Hazardous Materials, 92 (2), 185-198.

Full Text: J\J Haz Mat92, 185.pdf

Abstract: The adsorption of cobalt, chromium and nickel from aqueous solutions on IRN77 cation-exchange resin has been studied comparatively. The percentage removal of cobalt, chromium and nickel was examined by varying experimental conditions, viz. dosage of adsorbent, pH of the solution and contact time. It was found that more than 95% removal was achieved under optimal conditions. The adsorption capacity (k) for cobalt, chromium and nickel were calculated from the Freundlich adsorption isotherm. The adsorption of cobalt, chromium and nickel on this cation-exchange resin followed the Lagergren kinetic model. Also the competitive adsorption of multi-metals onto the IRN77 resin was studied. The studies showed that this cation-exchange resin can be used as an efficient adsorbent material for the removal of cobalt, chromium and nickel from water and nuclear power plant coolant water.

Keywords: Adsorption, Ion-Exchange Resin, Cobalt, Chromium, Nickel, Isotherm, Kinetics, Wastewater, Sphagnum Moss Peat, Ion-Exchange, Waste-Water, Aqueous-Solution, Chromium, Mercury, Lead

? Zhang, J. and Bishop, P.L. (2002), Stabilization/solidification (S/S) of mercury-containing wastes using reactivated carbon and Portland cement. Journal of Hazardous Materials, 92 (2), 199-212.

Full Text: 2002\J Haz Mat92, 199.pdf

Abstract: Stabilization/solidification (S/S) of mercury-containing solid wastes using activated carbon and cement was investigated in this study. The activated carbon used in the study was a powder reactivated carbon (PAC). The effect of sulfur-treatment of the PAC was also studied. It was found that PAC was effective in stabilizing Hg in the waste surrogate. Pretreatment of the PAC by soaking it in CS₂ significantly improved the mercury adsorption capacity of the PAC. The adsorption equilibrium was reached within 24 It. The optimum pH for the reaction was within the range of 5.0-5.5. After mercury stabilization by adsorption on the reactivated carbon, the Hg waste surrogate was mixed with Portland cement for solidification. Surrogates with up to 1000 mg/kg Hg were stabilized and solidified well enough to pass the TCLP test. The adsorption of mercury by reactivated carbon was in accordance with the Freundlich isotherm. Cement solidification of reactivated carbon-stabilized surrogates, significantly reduced the often-reported interference by chloride ions, by forming a barrier outside of the carbon particles. The S/S process using reactivated carbon and cement is an effective and economical technology for treating and disposing mercury-containing solid wastes. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Activated Carbon, Activated Carbon, Adsorption, Adsorption Capacity, Adsorption Equilibrium, Capacity, Carbon, Cement, Equilibrium, Freundlich, Freundlich Isotherm, Interference, Ions, Isotherm, Kinetics, Mercury, Mercury Adsorption, Mixed, PAC, pH, Portland Cement, Process, Removal, Rights, Sediments, Solid Wastes, Solidification, Stabilization, Sulfur, Sulfur, TCLP, Technology, Test, Water

? Wang, C.B., Yeh, T.F. and Lin, H.K. (2002), Nitric oxide adsorption and desorption on alumina supported palladium. Journal of Hazardous Materials, 92 (3), 241-251.

Full Text: 2002\J Haz Mat92, 241.pdf

Abstract: The adsorption properties of nitric oxide (NO) on alumina supported palladium were studied by a simultaneous thermogravimetric-analysis and differential-scanning-calorimetry (TGA-DSC) in a temperature ranges between 220 and 470 K. Upon adsorption, NO molecules on both Pd/Al₂O₃ and Pd/NaOH-Al₂O₃ samples were molecularly adsorbed between 220 and 300 K. Some NO molecules were strongly adsorbed on Pd/NaOH-Al₂O₃ and possessed a higher enthalpy of adsorption [similar to140 kJ (mol NO)^-1] than Pd/Al₂O₃ [similar to114 kJ (mol NO)^-1]. Upon heating above 320 K, the adsorbed NO molecule on these palladium surface was dissociated. In addition, a temperature programmed desorption and mass spectrometer (TPD-MS) study in a temperature range between 300 and 1100 K further indicated that some strongly adsorbed NO molecules may stay on basic sites (*(b)) and Pd-NaOH interface sites (*(i)) to enhance the decomposition of NO. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Adsorption, Adsorption Properties, Alumina, Calorimetry, Catalysts, Chemisorption, Decomposition, Desorption, Dioxygen, Exchanged ZSM-5, Heat Of Adsorption, Nitric Oxide, NO, NO Adsorption, Oxidation, Palladium, Pd(III), Platinum, Rights, Samples, Surface, Surfaces, Temperature

Jalali, R., Ghafourian, H., Asef, Y., Davarpanah, S.J. and Sepehr, S. (2002), Removal and recovery of lead using nonliving biomass of marine algae. Journal of Hazardous Materials, 92 (3), 253-262.

Full Text: J\J Haz Mat92, 253.pdf

Abstract: Batch equilibrium sorption experiments were used for screening for cost-effective marine algal biomass harvested from the Gulf of Persian. Biosorption of lead by eight brown, green and red marine algae was investigated. Biosorption of lead was rapidly occurred onto algal biosorbents and most of the sorbed metal was bound in < 30 min of contact. Three species of brown algae, namely Sargassum hystrix, S. natans and Padina pavonia, removed lead most efficiently from aqueous solution, respectively. The applicability of the Langmuir and Freundlich models for the different biosorbents was tested. An increasing uptake of the metal by biosorbents with increasing pH was demonstrated. Desorption of the adsorbed lead on biosorbent was conducted by decreasing the pH values to lower than 1.0. Removal of lead from Sargassum biomass was successfully achieved by eluting with 0.1 M HNO₃ for 15 min and a high degree of metal recovery was observed (95%). For optimum operation in the subsequent metal uptake cycle, regeneration of the Sargassum biomass was efficiently performed by 0.1 M CaCl₂ for 15 min that was total and reversible. In repeated use of biomass experiment, the lead uptake capacity of Sargassum biomass was constantly retained (98%) and no significant biomass damage took place after 10 sorption-desorption cycles. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Lead Biosorption, Desorption and Regeneration, Metal Removal, Marine Algae, Kinetics, Heavy-Metal Biosorption, Alginate, Yeast, Ions

Notes: highly cited

Annadurai, G., Juang, R.S. and Lee, D.J. (2002), Use of cellulose-based wastes for adsorption of dyes from aqueous solutions. Journal of Hazardous Materials, 92 (3), 263-274.

Full Text: J\J Haz Mat92, 263.pdf

Abstract: Low-cost banana and orange peels were prepared as adsorbents for the adsorption of dyes from aqueous solutions. Dye concentration and pH were varied. The adsorption capacities for both peels decreased in the order methyl orange (MO) > methylene blue (MB) > Rhodamine B (RB) > Congo red (CR) > methyl violet (MV) > amido black 10B (AB). The isotherm data could be well described by the Freundlich and Langmuir equations in the concentration range of 10–120 mg/l. An alkaline pH was favorable for the adsorption of dyes. Based on the adsorption capacity, it was shown that banana peel was more effective than orange peel. Kinetic parameters of adsorption such as the Langergren rate constant and the intraparticle diffusion rate constant were determined. For the present adsorption process intraparticle diffusion of dyes within the particle was identified to be rate limiting. Both peel wastes were shown to be promising materials for adsorption removal of dyes from aqueous solutions.

Keywords: Adsorbents, Adsorption, Adsorption Capacity, Aqueous Solutions, Capacity, Congo Red, Diffusion, Dye, Dyes, Freundlich, Intraparticle Diffusion, Isotherm, Kinetic, Kinetic Parameters, Langmuir, Methyl Violet, Methylene Blue, pH, Rate Constant, Removal, Removal of Dyes, Rights

Xu, Y.H., Nakajima, T. and Ohki, A. (2002), Adsorption and removal of arsenic(V) from drinking water by aluminum-loaded Shirasu-zeolite. Journal of Hazardous Materials, 92 (3), 275-287.

Full Text: J\J Haz Mat92, 275.pdf

Abstract: The demand for effective and inexpensive adsorbents is to increase in response to the widespread recognition of the deleterious health effects of arsenic exposure through drinking water. A novel adsorbent, aluminum-loaded Shirasu-zeolite P-1 (Al-SZP(1)), was prepared and employed for the adsorption and removal of arsenic(V) (As(V)) ion from aqueous system. The process of adsorption follows first-order kinetics and the adsorption behavior is fitted with a Freundlich isotherm. The adsorption of As(V) is slightly dependent on the initial pH over a wide range (3-10). Al-SZP(1) was found with a high As(V) adsorption ability, equivalent to that of activated alumina, and seems to be especially suitable for removal of As(V) in low concentration. The addition of arsenite, chloride, nitrate, sulfate, chromate, and acetate ions hardly affected the As(V) adsorption, whereas the coexisting phosphate greatly interfered with the adsorption. The adsorption mechanism is supposed as a ligand-exchange process between As(V) ions and the hydroxide groups present on the surface of Al-SZP(1). The adsorbed As(V) ions were desorbed effectively by a 40 mM NaOH solution. Continuous operation was demonstrated in a column packed with Al-SZP(1). The feasibility of this technique to practical utilization was also assessed by adsorption/desorption multiple cycles with in situ desorption/regeneration operation. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Arsenic(V), Adsorption, Aluminum-Loaded Shirasu-Zeolite, Regeneration, Removal, Coral Limestone, Sorption

? Qian, G.R., Li, Y.X., Yi, F.C. and Shi, R.M. (2002), Improvement of metakaolin on radioactive Sr and Cs immobilization of alkali-activated slag matrix. Journal of Hazardous Materials, 92 (3), 289-300.

Full Text: 2002\J Haz Mat92, 289.pdf

Abstract: Effects of metakaolin on simulated radioactive Sr or Cs immobilizing behavior of alkali-activated slag (AAS) matrix were evaluated by cation exchange capacity (CEC), distribution ratio of selective adsorption, leaching test and porosity analyses. The results revealed that the additions of metakaolin into the AAS matrixes largely enhanced their distribution ratios K_d of selective adsorption on Sr and Cs ions. Meanwhile, this new immobilizing matrix M-AAS showed the lowest leaching rate. Hydration product analyzes by XRD, DTA, FTIR and SEM demonstrated that (Na + Al)-substituted calcium silicate hydrate (CSH) and self-generated zeolite were major hydration products in the M-AAS matrix. These products have better Sr and Cs selective adsorption as compared to C-S-H without any substitution and natural zeolite minerals. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Aa, Aas, Adsorption, Alkali-Activated Slag, Behavior, C-S-H, Calcium, Capacity, Cation Exchange, Cation Exchange Capacity, Cation Exchangers, CEC, Cement, Distribution, Exchange, Forms, FTIR, Hydration Products, Immobilization, Ions, Leaching, Metakaolin, Natural, Natural Zeolite, Porosity, Rights, Selective Adsorption, SEM, Simulated Radioactive Sr or Cs Waste, Slag, Test, Tobermorite, XRD, Zeolite

Notes: highly cited

Lin, S.H. and Juang, R.S. (2002), Heavy metal removal from water by sorption using surfactant-modified montmorillonite. Journal of Hazardous Materials, 92 (3), 315-326.

Full Text: J\J Haz Mat92, 315.pdf

Abstract: Removal of Cu²⁺ and Zn²⁺ from aqueous solutions by sorption on the montmorillonite modified with sodium dodecylsulfate (SDS) was investigated. Experiments were carried out as a function of solution pH, solute concentration, and temperature (25-55 degreesC). The Dubinin-Kaganer-Radushkevick model was adopted to describe the single-solute sorption isotherms. Also, the binary-solute sorption equilibria could be reasonably predicted by the competitive Langmuir model, in which the Langmuir parameters were directly taken from those obtained in single-solute systems. The thermodynamic parameters (DeltaH(o) and DeltaS(o)) for Cu²⁺ and Zn²⁺ sorption on the modified clay were also determined from the temperature dependence. The kinetics of metal ions sorption was examined and the pseudo-first-order rate constant was finally evaluated. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Adsorption, Chromate, Clay, Concentration, Cu²⁺, Dependence, Isotherms, Kinetics, Langmuir, Metal Ions, Model, Modified, Modified Clay, Montmorillonite, Parameters, pH, Rate Constant, Removal, Sodium, Sodium Dodecylsulfate, Sorption, Sorption Isotherm, Sorption Isotherms, Temperature, Temperature Dependence, Thermodynamic, Thermodynamic Parameters, Water, Zeolite, Zn²⁺

? Kim, S.D., Park, K.S. and Gu, M.B. (2002), Toxicity of hexavalent chromium to Daphnia magna: Influence of reduction reaction by ferrous iron. Journal of Hazardous Materials, 93 (2), 155-164.

Full Text: 2002\J Haz Mat93, 155.pdf

Abstract: The reaction kinetics of hexavalent chromium with ferrous ions were studied to determine the influence of reduction on the toxicity of chromium to aquatic organisms. The changes in chemical forms of the chromate in the presence of ferrous ions were examined in a bioassay system using Daphnia magna as a test organism. This study demonstrated that the reaction kinetics of chromate with ferrous ions showed a significant decrease of chromate concentration with the second-order rate coefficient (k) for the reduction of Cr(VI) being determined as 55.2 M⁻¹ s⁻¹. The concentration of Cr(VI) remaining in the solution decreased as the ratio of ferrous ion to chromate increased, revealing a non-stoichiometric reaction due to oxygenation and the moderately alkaline pH of the solutions. The toxicity test indicated that the bioavailability of chromate to D. magna was reduced in the presence of Fe(II) and that it decreased further with increasing Fe(II) concentrations. However, the toxic effect of chromate to aquatic organisms was not controlled kinetically in the presence of ferrous ions. It was also found that LC50 of chromate to D. magna decreased about 1.5-fold as the test period increased from 24 to 48 h in the presence of Fe(II).

Keywords: Hexavalent Chromium, Reduction, Ferrous Ion, Toxicity, Daphnia Magna

Notes: highly cited

Chiou, M.S. and Li, H.Y. (2002), Equilibrium and kinetic modeling of adsorption of reactive dye on cross-linked chitosan beads. Journal of Hazardous Materials, 93 (2), 233-248.

Full Text: J\J Haz Mat93, 233.pdf

Abstract: The adsorption of reactive dye (Reactive Red 189) from aqueous solutions on cross-linked chitosan beads was studied in a batch system. The equilibrium isotherms at different particle sizes (2.3-2.5, 2.5-2.7 and 3.5-3.8 mm) and the kinetics of adsorption with respect to the initial dye concentration (4320, 5760 and 7286 g/m³), temperature (30, 40 and 50°C), pH (1.0, 3.0, 6.0 and 9.0), and cross-linking ratio (cross-linking agent/chitosan weight ratio: 0.2, 0.5, 0.7 and 1.0) were investigated. Langmuir and Freundlich adsorption models were applied to describe the experimental isotherms and isotherm constants. Equilibrium data fitted very well to the Langmuir model in the entire saturation concentration range (0-1800 g/m³). The maximum monolayer adsorption capacities obtained from the Langmuir model are very large, which are 1936, 1686 and 1642 g/kg for small, mediumand large particle sizes, respectively, at pH 3, 0, 30°C, and the cross-linking ratio of 0.2. The pseudo first- and second-order kinetic models were used to describe the kinetic data, and the rate constants were evaluated. The experimental data fitted well to the second-order kinetic model, which indicates that the chemical sorption is the rate-limiting step, instead of mass transfer. The initial dye concentration and the solution pH both significantly affect the adsorption capacity, but the temperature and the cross-linking ratio are relatively minor factors. An increase in initial dye concentration results in the increase of adsorption capacity, which also increases with decreasing pH. The activation energy is 43.0 kJ/mol for the adsorption of the dye on the cross-linked chitosan beads at pH 3.0 and initial dye concentration 3768 g/m³. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Activation, Activation Energy, Adsorption, Adsorption Capacities, Adsorption Capacity, Adsorption Rate, Aqueous Solutions, Batch, Batch System, Beads, Capacity, Chemical, Chitosan, Concentration, Cross-Linked, Cross-Linked Chitosan, Crosslinked Chitosan, Crosslinking, Data, Dye, Energy, Equilibrium, Experimental, First, Freundlich, Isotherm, Isotherms, Kinetic, Kinetic Model, Kinetic Modeling, Kinetic Models, Kinetics, Kinetics of Adsorption, Langmuir, Langmuir Model, Mass Transfer, Minor, Model, Modeling, Models, Monolayer, pH, Rate Constants, Rate Limiting Step, Rate-Limiting Step, Reactive Dye, Saturation, Second Order, Second-Order, Small, Solution, Solutions, Sorption, Temperature

? Rasmussen, G., Fremmersvik, G. and Olsen, R.A. (2002), Treatment of creosote-contaminated groundwater in a peat/sand permeable barrier - a column study. Journal of Hazardous Materials, 93 (3), 285-306.

Full Text: 2002\J Haz Mat93, 285.pdf

Abstract: A column study was conducted to determine if a permeable barrier can be used to treat creosote-contaminated groundwater based on sorption and biodegradation, and to determine which processes remove the various creosote compounds. Creosote-contaminated water (sterile and non-sterile) was applied to sterile and non-sterile saturated columns with peat (20 vol.%) and sand (80 vol.%) for 2 months. Temperature was 9degreesC, inlet oxygen concentration 9-10 mg/l and average residence time was two days. The peat/sand barrier material removed 94-100% polycyclic aromatic hydrocarbons (PAHs), 93-98% nitrogen/sulfur/oxygen (NSO)-containing heterocyclic aromatic compounds, and 44-97% total phenols. The peat/sand material efficiently sorbed PAHs (>2 rings) and three-ring NSO-compounds, and also sorbed significant amounts of two-ring NSO-compounds and naphthalene. Naphthalene and NSO-compounds not sorbed were biological degraded. Phenol and cresols were efficiently removed by microbial degradation. The barrier material was somewhat less efficient removing dimethylphenols (DMPs) and trimethylphenols (TMPs), where DMPs were hardly sorbed and TMPs were hardly degraded. The results imply that a peat/sand barrier can treat creosote-contaminated groundwater. Modifications might be needed for enhanced removal of DMPs and TMPs, and oxygen. supply might be necessary in aquifers with low oxygen content. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Biodegradation, Bioremediation, Borden Aquifer, Column, Column Study, Creosote, Degradation, Groundwater, Heterocyclic-Compounds, Hydrocarbons, Microbial-Populations, Naphthalene, PAHs, Peat, Permeable Barrier, Phenol, Phenols, Polycyclic Aromatic Hydrocarbons, Remediation, Removal, Rights, Sand, Sorption, Sorption, Supply, Temperature, Treatment, Waste-Water, Water, Zerovalent Iron

? Hisanaga, T. and Tanaka, K. (2002), Photocatalytic degradation of benzene on zeolite-incorporated TiO₂ film. Journal of Hazardous Materials, 93 (3), 331-337.

Full Text: 2002\J Haz Mat93, 331.pdf

Abstract: Zeolite powder was incorporated into the TiO₂ film. Their photoactivities were evaluated for the gas phase degradation of benzene. Seven zeolite samples were used in this study and each enhanced the photocatalytic degradation. Humidity in the gas sample increased the degradation, but suppressed the adsorption of benzene to the TiO₂ film. It was noted that the photoactivity was inversely proportional to the silica/alumina ratio of zeolite, whereas adsorption increased with this ratio. It was suggested that the adsorption of water onto zeolite contributes to the enhancement of benzene degradation. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Activated Carbon, Adsorption, Benzene, Decomposition, Degradation, Enhancement, Film, Gas Phase, Gas-Phase, Humidity, Photoactivity, Photocatalysis, Photocatalytic, Photocatalytic Degradation, Raman, Ratio, Rights, Samples, Sites, TiO₂, Titanium-Dioxide, Water, Zeolite

? Daneshvar, N., Salari, D. and Aber, S. (2002), Chromium adsorption and Cr(VI) reduction to trivalent chromium in aqueous solutions by soya cake. Journal of Hazardous Materials, 94 (1), 49-61.

Full Text: 2002\J Haz Mat94, 49.pdf

Abstract: Chromium as Cr(VI) is a industrially produced pollutant. Hexavalent chromium can be reduced to the trivalent state using various reductive agents or it can be removed from solution by surface-active adsorbents. In this study, both of these methods were evaluated using soya cake. A high efficiency for reduction of Cr(VI) to trivalent chromium was observed at pH < 1. Increasing the temperature, also increased the yield. Experimentally, the optimum time and soya cake mass were 5 It and 0.7 g, respectively. In the second treatment method, a high efficiency for adsorption of chromium was also observed at pH < 1. The favorable temperature for adsorption was found to be 20 °C. Experimentally, the best time was 1h and with increasing soya cake mass up to 30g, the adsorption efficiency was increased. Dissolution of LiCl in the experimental solutions, increased the efficiency of adsorption, however, this effect was not observed in the case of KCl. Langmuir isotherm constants, Q and b, for ground soybeans, were found to be 2.8×10^-4 mg/mg and 0.623, respectively. Freundlich isotherm constants, K_f and n, were found to be 1.4×10^-4 and 4.99, respectively, (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Adsorbents, Adsorption, Aqueous Solutions, Chitosan, Chromium, Chromium Adsorption, Cr(III), Cr(VI), Cr(VI) Reduction, Efficiency, Freundlich, Freundlich Isotherm, Hexavalent Chromium, Isotherm, Langmuir, Langmuir Isotherm, Methods, pH, Reduction, Rights, Soya Cake, State, Temperature, Treatment, Trivalent Chromium

? Hui, C.A., Yang, R.Q., Zhu, K., Zhou, W.J. and Jiang, M. (2002), Attenuating toluene mobility in loess soil modified with anion-cation surfactants. Journal of Hazardous Materials,