Personal Research Database

Full Text: J\J Haz Mat117, 121.pdf

Abstract: The effects of trinitrotoluene (TNT) dynamic adsorption on granular activated carbon produced by ‘Miloje Zakic’, Serbia, are presented. The main task was to determine the conditions for TNT dynamic adsorption in order to remove the dissolved TNT from wastewater. The effects of temperature, concentration and flow rate in the chromatographic system were examined. Flow rates between 1 and 4 dm³/h were used. The heights of activated carbon in the columns were 70 and 135 mm while the diameter was 12 mm. The experiments were conducted at different temperatures (10–60 °C) and TNT influent concentrations ranging from 32.76 to 171 mg/dm³ were used. The adsorption capacity of the activated carbon increased with increasing temperature, but it decreased with increasing input concentration and flow rate. The results obtained indicate that the influence of temperature is greater than was expected and the bed height and the amount of GAC used could be significantly lowered by increasing the temperature. The possibility of desorbing TNT from saturated activated carbon was also investigated. The amount of TNT adsorbed per mass unit of adsorbent was calculated using a model that optimally agreed with the experimental data.

Keywords: Trinitrotoluene, Granular activated carbon, Dynamic adsorption

Mittal, A., Kurup, (Krishnan) L. and Gupta, V.K. (2005), Use of waste materials: Bottom ash and De-Oiled Soya, as potential adsorbents for the removal of Amaranth from aqueous solutions. Journal of Hazardous Materials, 117 (2-3), 171-178.

Full Text: J\J Haz Mat117, 171.pdf

Abstract: Bottom Ash, a power plant waste material and De-Oiled Soya, an agriculture waste product were successfully utilized in removing trisodium 2-hydroxy-1-(4-sulphonato-1-naphthylazo)naphthalene-3,6-disulphonate—a water-soluble hazardous azo dye (Amaranth). The paper incorporates thermodynamic and kinetic studies for the adsorption of the dye on these two waste materials as adsorbents. Characterization of each adsorbent was carried out by I.R. and D.T.A. curves. Batch adsorption studies were made by measuring effects of pH, adsorbate concentration, sieve size, adsorbent dosage, contact time, temperature etc. Specific rate constants for the processes were calculated by kinetic measurements and a first order adsorption kinetics was observed in each case. Langmuir and Freundlich adsorption isotherms were applied to calculate thermodynamic parameters. The adsorption on Bottom Ash takes place via film diffusion process at lower concentrations and via particle diffusion process at higher concentrations, while in the case of De-Oiled Soya process only particle diffusion takes place in the entire concentration range.

Keywords: Adsorbent, Adsorbent Dosage, Adsorbents, Adsorption, Adsorption Isotherms, Adsorption Kinetics, Agriculture, Amaranth, Aqueous Solutions, Azo Dye, Batch Adsorption, Bottom Ash, Characterization, Concentration, De-Oiled Soya, Diffusion, Dye, Film Diffusion, First, First Order, Freundlich, Isotherms, Kinetic, Kinetic Studies, Kinetics, Langmuir, Particle Diffusion, pH, Plant, Potential, Power, Power Plant, Rate Constants, Removal, Size, Solutions, Temperature, Thermodynamic, Thermodynamic Parameters, Waste, Waste Material, Waste Materials

Montanher, S.F., Oliveira, E.A. and Rollemberg, M.C. (2005), Removal of metal ions from aqueous solutions by sorption onto rice bran. Journal of Hazardous Materials, 117 (2-3), 207-211.

Full Text: J\J Haz Mat117, 211.pdf

Abstract: A new sorbent (raw rice bran) was investigated for heavy metal ions removal from aqueous solutions. Rice bran characterisation was carried out in order to identify the functional groups possibly involved in the metal binding. The binding process was studied in terms of binding capacity and metal affinity. The adsorption equilibrium was well described by the Freundlich isotherm model. The negative Gibbs free energy values obtained in this study with rice bran confirm the feasibility of the process and the spontaneous nature of sorption.

Keywords: Rice Bran, Biosorption, Heavy Metal Ions, Freundlich Isotherm

Yılmaz, A.E., Boncukcuoglu, R., Yılmaz, M.T. and Kocakerim, M.M. (2005), Adsorption of boron from boron-containing wastewaters by ion exchange in a continuous reactor. Journal of Hazardous Materials, 117 (2-3), 221-226.

Full Text: J\J Haz Mat117, 221.pdf

Abstract: In this study, boron removal from boron-containing wastewaters prepared synthetically was investigated. The experiments in which Amberlite IRA 743, boron specific resin was used were carried out in a column reactor. The bed volume of resin, boron concentration, flow rate and temperature were selected as experimental parameters.

The experimental results showed that percent of boron removal increased with increasing amount of resin and with decreasing boron concentration in the solution. Boron removal decreased with increasing of flow rate and the effect of temperature on the percent of total boron removal increased the boron removal rate. As a result, it was seen that about 99% of boron in the wastewater could be removed at optimum conditions.

Keywords: Boron Removal, Ion Exchange, Amberlite IRA 743, Wastewater, Adsorption

Oguz, E. (2005), Adsorption of fluoride on gas concrete materials. Journal of Hazardous Materials, 117 (2-3), 227-233.

Full Text: J\J Haz Mat117, 227.pdf

Abstract: In this study, gas concrete waste materials were used to remove F⁻ from aqueous solutions. The influence of pH, temperature, agitation rate and gas concrete dosage on F⁻ removal was investigated by conducting a series of batch adsorption experiments. In addition, the yield and mechanisms of F⁻ removal were explained on the basis of the results of X-ray spectroscopy and images of scanning electron microscopy (SEM) of the particles before and after adsorption. The values of zeta potential and BET-N₂ specific surface area of gas concrete particles were defined. In this study, F⁻ removal in excess of 96% was obtained. It was thought that the removal of fluoride by gas concrete took place both adsorption and precipitation of Al³⁺ and Ca²⁺ salts (F⁻). As a result of this study, it was concluded that wastes of gas concrete were an efficient adsorbent for the removal of F⁻.

Keywords: Fluoride, Adsorption, Gas Concrete, XRD, SEM

Benhammou, A., Yaacoubi, A., Nibou, L. and Tanouti, B. (2005), Study of the removal of mercury(II) and chromium(VI) from aqueous solutions by Moroccan stevensite. Journal of Hazardous Materials, 117 (2-3), 243-249.

Full Text: J\J Haz Mat117, 243.pdf

Abstract: The objective of the present study was to investigate the adsorption of the heavy metals mercury(II) and chromium(VI), from aqueous solutions, onto Moroccan stevensite. A mineralogical and physicochemical characterization of natural stevensite was carried out. In order to improve the adsorption capacity of stevensite for Cr(VI), a preparation of stevensite was carried out. It consists in saturating the stevensite by ferrous iron Fe(II) and reducing the total Fe by Na₂S₂O₄. Then, the adsorption experiments were studied in batch reactors at 25±3°C. The influence of the pH solution on the Cr(VI) and Hg(II) adsorption was studied in the pH range of 1.5–7.0. The optimum pH for the Cr(VI) adsorption is in the pH range of 2.0–5.0 while that of Hg(II) is at the pH values above 4.0. The adsorption kinetics were tested by a pseudo-second-order model. The adsorption rate of Hg(II) is 54.35 mmol kg⁻¹ min⁻¹ and that of Cr(VI) is 7.21 mmol kg⁻¹ min⁻¹. The adsorption equilibrium time for Hg(II) and Cr(VI) was reached within 2 and 12 h, respectively. The adsorption isotherms were described by the Dubinin–Radushkevich model. The maximal adsorption capacity for Cr(VI) increases from 13.7 (raw stevensite) to 48.86 mmol kg⁻¹ (modified stevensite) while that of Hg(II) decreases from 205.8 to 166.9 mmol kg⁻¹. The mechanism of Hg(II) and Cr(VI) adsorption was discussed.

Keywords: Adsorption, Adsorption Capacity, Adsorption Equilibrium, Adsorption Isotherms, Adsorption Kinetics, Adsorption Rate, Aqueous Solutions, Batch, Capacity, Characterization, Chromium(VI), Cr(VI), Cr(VI) Adsorption, Equilibrium, Experiments, Heavy Metals, Hg(II), Iron, Isotherm, Isotherms, Kinetic, Kinetics, Mechanism, Mercury(II), Metals, Model, Modified, Moroccan Stevensite, pH, Preparation, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Removal, Solution, Solutions, Stevensite

Ichcho, S., Khouya, E., Fakhi, S., Ezzine, M., Hannache, H., Pallier, R. and Naslain, R. (2005), Influence of the experimental conditions on porosity and structure of adsorbents elaborated from Moroccan oil shale of Timahdit by chemical activation. Journal of Hazardous Materials, 118 (1-3), 45-51.

Full Text: J\J Haz Mat118, 45.pdf

Abstract: This study records experiments undertaken to determine the suitable conditions for the use of the oil shale of Timahdit, as an adsorbent for water treatment. A simple process was proposed based on chemical activation. The preparation has been carried out by carbonization after impregnation of the precursor with phosphoric acid. The effect of different conditions of preparation on the specific surface area is discussed. These parameters are H₃PO₄/shale weight ratio, carbonization temperature, carbonization time and concentration of H₃PO₄. The properties and surface structure of the adsorbent were investigated by XPS and FT-IR. Their total surface acidity and basicity were also determined. The retention process of methylene blue (MB) by adsorbents has been studied. It was found that MHP2 and MHP7 have relatively high retention ability as compared to activated carbons.

Keywords: Oil Shale, Phosphoric Acid, Specific Surface Area, Methylene Blue

Karunasagar, D., Krishna, M.V.B., Rao, S.V. and Arunachalam, J. (2005), Removal and preconcentration of inorganic and methyl mercury from aqueous media using a sorbent prepared from the plant Coriandrum sativum. Journal of Hazardous Materials, 118 (1-3), 133-139.

Full Text: J\J Haz Mat118, 133.pdf

Abstract: A sorbent prepared from the plant Coriandrum sativum, commonly known as coriander or Chinese parsley, was observed to remove inorganic (Hg²⁺) and methyl mercury (CH₃Hg⁺) from aqueous solutions with good efficiency. Batch experiments were carried out to determine the pH dependency in the range 1–10 and the time profiles of sorption for both the species. Removal of both the forms of mercury from spiked ground water samples was found to be efficient and not influenced by other ions. Column experiments with silica-immobilized coriander demonstrated that the sorbent is capable of removing considerable amounts of both forms of mercury from water. The sorption behaviour indicates the major role of carboxylic acid groups in binding the mercury. The studies suggest that the sorbent can be used for the decontamination of inorganic and methyl mercury from contaminated waters.

Keywords: Coriander, Sorption, Mercury, Methyl Mercury, CV-AAS, Ground Water Remediation

Uzun, İ. and Güzel, F. (2005), Rate studies on the adsorption of some dyestuffs and p-nitrophenol by chitosan and monocarboxymethylated(mcm)-chitosan from aqueous solution. Journal of Hazardous Materials, 118 (1-3), 141-145.

Full Text: J\J Haz Mat118, 141.pdf

Abstract: In this study, the effect of temperature on the adsorption of some dyestuffs [orange II (O-II), crystal violet (CV) and reactive blue 5 (RB5)] and p-nitrophenol (PNP) by chitosan and of O-II and CV by modified chitosan [monocarboxymethylated(mcm)-chitosan] from aqueous solution was investigated. Kinetical data related to the adsorptions of each dyestuff and PNP by chitosan and of O-II and CV by mcm–chitosan were applied to Lagergren and Weber–Morris equations, and adsorption rate constants (k_ads) and pore diffusion rate constants (k_p) were determined, respectively. In addition, Langmuir isotherm constants with experimental data related to the adsorptions of O-II and CV by chitosan and of CV by mcm-chitosan were applied to McKay et al. equation, and external mass transfer coefficients (k_f) were also determined. Lastly, chitosan and mcm-chitosan were compared according to their dyestuffs and PNP uptake capabilities. It was seen that mcm-chitosan removed more O-II (99.2%) and RB5 (34.9%) but less CV (3.1%) and PNP (0.9%).

Keywords: Chitosan, Dyestuff Adsorption, Diffusion, Mass Transfer

Khan, Z. and Anjaneyulu, Y. (2005), Influence of soil components on adsorption–desorption of hazardous organics-development of low cost technology for reclamation of hazardous waste dumpsites. Journal of Hazardous Materials, 118 (1-3), 161-169.

Full Text: J\J Haz Mat118, 161.pdf

Abstract: The waste disposal practices on land frequently lead to the deposition of hazardous waste at geologically/hydrogeologically unsuitable locations, resulting in surface and groundwater contamination. The movement of chemicals through soil is not only dependent on the physical, chemical and biological properties of the waste but also on the characteristics of the soil of the disposal site. In this paper the authors report their results on the influence of soil components on adsorption–desorption of certain industrially widely used hazardous organics like phenol, p-nitrophenol, 4-chloro-2-nitrophenol and 2,4-dichlorophenol on typical soils of Patancheru industrial area (Hyderabad, AP, India). The data on nature of organics, soil organic matters, clay, free iron and aluminum oxides of soils are known to influence the adsorption–desorption process are presented. There was reduction up to 67.5% (organic matter removed), 53.8% (clay removed) and 24.2% (iron and aluminum oxides removed) in the adsorption capacity of the soils when compared to untreated soils indicating the role played by these soil components in adsorption process. Desorption isotherms of soil adsorbed hazardous organics exhibited hysteresis at higher initial concentration indicating the degree of irreversibility of adsorption–desorption process. Mixed microbial cultures were developed which can degrade the hazardous organics to complete mineralisation by utilizing them as sole source of carbon and their corresponding biokinetic constants were evaluated. Preparation of dumpsites with suitable soil surface having high holding capacity for organics and their in situ biodegradation by mixing with specific microbial cultures can be exploited as a cost effective technology for reclamation of hazardous waste dumpsites.

Keywords: Adsorption, Desorption, Biodegradation, Hazardous Waste Dumpsites, Soil, Organic Compounds

Baciocchi, R., Boni, M.R. and Lavecchia, R. (2005), Modeling of chlorophenols competitive adsorption on soils by means of the ideal adsorbed solution theory. Journal of Hazardous Materials, 118 (1-3), 239-246.

Full Text: J\J Haz Mat118, 239.pdf

Abstract: The adsorption of 3-chlorophenol (3-CP) and 3,5-dichlorophenol (3,5-CP) on two Italian soils was studied at 20 °C. Experiments on the pure components showed that 3,5-CP was more strongly adsorbed than 3-CP, and that the adsorption capacity could be related to the organic carbon fraction of the soil.

Competitive adsorption data were described by the fully predictive ideal adsorbed solution (IAS) theory. To this end, the Langmuir parameters determined from pure component adsorption data were used. Results showed that at low 3,5-CP concentration (up to 5–10 mM) the model describes satisfactorily the binary system behavior, whereas at higher concentrations predictions fail, suggesting that non ideality effects in the adsorbed phase should be accounted for.

Keywords: Competitive Adsorption, 3-Chlorophenol, 3,5-Dichlorophenol, Soil, IAS

Ho, Y.S. (2005), Comment on “Nitrate removal from aqueous solution by adsorption onto various materials” by N. Öztürk, T.E. Bektaş. Journal of Hazardous Materials, 118 (1-3), 253-254.

Full Text: J\J Haz Mat118, 253.pdf J\J Haz Mat-Ho2.pdf J\J Haz Mat-Ho1.pdf

Abstract: A research paper’s contribution exists not only in its originality and creativity but also in its continuity and development for research that follows. The reference section can play a key role to researchers who are interested in a paper’s statement or who would like to follow the study or find useful information from the paper. Citation error and quotation error occurred very frequently in a scientific paper, however, the author easily ignores it. Öztürk and Bektaş published a paper, there is no doubt about this paper, which was previously evaluated and accepted for publication. This study presents quotation and citation errors of Lagergren’s pseudo-first order rate equation and Ho’s pseudo-second order rate expression. It is also suggested that an author not only must be creative but also must be careful while writing in order to publish more valuable and papers more worthy of reading.

Keywords: Adsorption, Aqueous Solution, Citation, Citation Error, Citation Errors, Comment on, Contribution, Creativity, Development, Dye, Equilibrium, Error, Errors, Expression, Information, Kinetic-Models, Kinetics, N, Papers, Peat, Play, Pseudo First Order, Pseudo Second Order, Pseudo-First Order, Pseudo-First-Order, Pseudo-Second Order, Pseudo-Second-Order, Publication, Quotation, Quotation Error, Reading, Reference, Removal, Research, Rights, Role, Solution, Sorption

Legrouri, K., Khouya, E., Ezzine, M., Hannache, H., Denoyel, R., Pallier, R. and Naslain, R. (2005), Production of activated carbon from a new precursor molasses by activation with sulphuric acid. Journal of Hazardous Materials, 118 (1-3), 259-263.

Full Text: J\J Haz Mat118, 259.pdf

Abstract: Activated carbon has been prepared from molasses, a natural precursor of vegetable origin resulting from the sugar industry in Morocco. The preparation of the activated carbon from the molasses has been carried out by impregnation of the precursor with sulphuric acid, followed by carbonisation at varying conditions (temperature and gas coverage) in order to optimize preparation parameters. The influence of activation conditions was investigated by determination of adsorption capacity of methylene blue and iodine, the BET surface area, and the pore volume of the activated carbon were determined while the micropore volume was determined by the Dubinin–Radushkevich (DR) equation. The activated materials are mainly microporous and reveal the type I isotherm of the Brunauer classification for nitrogen adsorption. The activated carbons properties in this study were found for activation of the mixture (molasses/sulphuric acid) in steam at 750 °C. The samples obtained in this condition were highly microporous, with high surface area (≥1200 m²/g) and the maximum adsorption capacity of methylene blue and iodine were 435 and 1430 mg/g, respectively.

Keywords: Activated Carbon, Molasses, Sulphuric Acid, Adsorption, Microporosity

Gulnaz, O. (2005), Reply to comment of Dr. Ho on “J. Hazard. Mater. 108 (2004) 183-188”. Journal of Hazardous Materials, 118 (1-3), 265.

Full Text: J\J Haz Mat118, 265.pdf

Kusvuran, E., Irmak, S., Yavuz, H.I., Samil, A. and Erbatur, O. (2005), Comparison of the treatment methods efficiency for decolorization and mineralization of Reactive Black 5 azo dye. Journal of Hazardous Materials, 119 (1-3), 109-116.

Full Text: J\J Haz Mat119, 109.pdf

Abstract: Degradation of Reactive Black 5 (RB5), a well-known non-biodegradable disazo dye, has been studied using UV/TiO₂, wet-air oxidation (WAO), electro-Fenton (EF) and UV/electro-Fenton (UV/EF) advanced oxidation processes (AOPs). The efficiency of substrate decolorization and mineralization in each process has been comparatively discussed by decreases in concentration and total organic carbon content of RB5 solutions. The most efficient method on decolorization and mineralization was observed to be WAO process. Mineralization efficiency was observed in the order of WAO > UV/TiO₂ > UV/EF > EF. Final solutions of AOPs applications after 90 min treatment can be disposed safely to environment. Photocatalytic degradation kinetics of RB5 successfully fitted to Langmuir–Hinshelwood (L–H) kinetics model. The values of second order degradation rate constant (k”) and adsorption constant (K) were determined as 5.085 mg L⁻¹ min⁻¹ and 0.112 L mg⁻¹, respectively.

Keywords: Reactive Black 5, Advanced Oxidation Processes, L–H Kinetics, Decolorization, Mineralization

Bouberka, Z., Kacha, S., Kameche, M., Elmaleh, S. and Derriche, Z. (2005), Sorption study of an acid dye from an aqueous solutions using modified clays. Journal of Hazardous Materials, 119 (1-3), 117-124.

Full Text: J\J Haz Mat119, 117.pdf

Abstract: The removal of the pollutant Supranol Yellow 4GL (S.Y.4GL) was studied by using different clays: clay exchanged with sodium (BNa⁺) and hydroxyaluminic polycation pillared clays in the presence or absence of non-ionic surfactant. While decomposing the surfactant at 500°C, the surface of the clay changed significantly. The study of the behaviour of the three clays with respect to coloring solutions, allowed to determine the equilibrium time and the rate-determining step of the dye S.Y.4GL adsorption. Two simplified kinetic models, were tested to investigate the adsorption mechanisms in terms of pseudo-first order and pseudo-second order equations. Besides, the adsorption capacity data were fitted to Langmuir and Freundlich equations as well. A better fixation was obtained with an acidic pH. The effect of temperature on the adsorption of dye has been also studied and the thermodynamic parameters ΔG°, ΔH° and ΔS° were determined.

Keywords: Acid Dye, Acidic Dye, Adsorption, Adsorption, Adsorption Capacity, Adsorption Mechanisms, Aqueous Solutions, Behaviour, Bentonite, Capacity, Cation-Exchange Capacity, Clay, Clays, Color Removal, Data, Dye, Equilibrium, Freundlich, Kinetic, Kinetic Models, Langmuir, Mar, Mechanism, Mechanisms, Methylene-Blue, Models, Modified, Modified Clay, Modified Clays, Nonionic Surfactant, Organic-Compounds, pH, Phenol, Pillared Montmorillonite, Pseudo First Order, Pseudo Second Order, Pseudo-First Order, Pseudo-First Order and Pseudo-Second Order, Pseudo-First-Order, Pseudo-Second Order, Pseudo-Second-Order, Rate-Determining Step, Removal, Rights, Sodium, Solutions, Sorption, Supranol Yellow 4GL, Surface, Surfactant, Temperature, Thermodynamic, Thermodynamic Parameters

Gode, F., and Pehlivan, E. (2005), Removal of Cr(VI) from aqueous solution by two Lewatit-anion exchange resins. Journal of Hazardous Materials, 119 (1-3), 175-182.

Full Text: J\J Haz Mat119, 175.pdf

Abstract: The sorption of hexavalent chromium, Cr(VI), from aqueous solutions on macroporous resins containing tertiary amine groups (Lewatit MP 62 and Lewatit M 610) was studied at varying Cr(VI) concentrations, adsorbent dose, pH, contact time and temperatures. The concentration of chromium in aqueous solution was determined by inductively coupled plasma spectrometry (ICP–AES). Batch shaking sorption experiments were carried out to evaluate the performance of Lewatit MP 62 and Lewatit M 610 anion exchange resins in the removal of Cr(VI) from aqueous solutions. The ion-exchange process, which is pH dependent, shows maximum removal of Cr(VI) in the pH range 2–6 for an initial Cr(VI) concentration of 100 ppm. The sorption increases with the decrease in pH and slightly decreases with the increase in temperature. Both ion exchangers had high bonding constants with Lewatit M 610 showing stronger binding. It was observed that the maximum adsorption capacity of 0.40 mmol of Cr(VI)/g for Lewatit MP 62 and 0.41 mmol of Cr(VI)/g for Lewatit M 610 was achieved at pH of 5.0. The thermodynamic parameters (free energy change, ΔG°; enthalpy change, ΔS°; and entropy change, ΔH°) for the sorption have been evaluated. The rise in temperature caused a slight decrease in the value of the equilibrium constant (K_c) for the sorption of Cr(VI) ion. The sorption of Cr(VI) on the resin was rapid during the first 15 min and equilibrium was found to be attained within 30 min. The sorption of Cr(VI) onto the resins followed reversible first-order rate kinetics. Such ion exchange resins can be used for the efficient removal of chromium from water and wastewater.

Keywords: Anion-Exchange Resin, Batch Adsorption,Cr(VI), Adsorption Isotherms

Mouflih, M., Aklil, A. and Sebti, S. (2005), Removal of lead from aqueous solutions by activated phosphate. Journal of Hazardous Materials,