Title: Separation Science and Technology

Title: Separation Science and Technology

ISO Abbreviated Title: Sep. Sci. Technol.

JCR Abbreviated Title: Separ Sci Technol

ISSN: 0149-6395

Issues/Year: 21

Journal Country United States

Language: English

Publisher: Marcel Dekker Inc

Publisher Address: 270 Madison Ave, New York, NY 10016

Subject Categories:

Chemistry, Multidisciplinary: Impact Factor 0.911, 44/121 (1999), Impact Factor 0.725, 60/118 (2000), Impact Factor 0.862, 49/118 (2001), Impact Factor 0.779, 57/119 (2002), Impact Factor 0.890, 54/123 (2003), Impact Factor 0.896, 59/125 (2004), Impact Factor 0.834, 69/125 (2005), Impact Factor 0.824, 70/124 (2006), Impact Factor 1.048, 63/127 (2007), Impact Factor 1.028, 74/138 (2009)

Engineering, Chemical: Impact Factor 0.911, 23/110 (1999), Impact Factor 0.725, 29/117 (2000), Impact Factor 0.862, 33/123 (2001), Impact Factor 0.779, 44/126 (2002), Impact Factor 0.890, 38/119 (2003), Impact Factor 0.896, 44/116 (2004), Impact Factor 0.834, 49/116 (2005), Impact Factor 0.824, 48/110 (2006), Impact Factor 1.048, 43/114 (2007), Impact Factor 1.028, 57/126 (2009)

? Bhattacharyya, D., Jumawan, A.B. and Grieves, R.B. (1979), Separation of toxic heavy metals by sulfide precipitation. Separation Science and Technology, 14 (5), 441-452.

Full Text: 1960-80\Sep Sci Tec14, 441.pdf

Abstract: Sulfide precipitation with Na₂S is found to be highly effective to obtain a high degree of separation of heavy metal cations (Cd, Zn, Cu, and Pb) and of the oxyanions of arsenic and selenium from complex wastewaters. The metal separation characteristics are evaluated with a dilute synthetic mixture and with an actual copper smelting plant wastewater. The overall separation of arsenic and other heavy metals and precipitate settling rates are optimum at sulfide dosages about 60% of the theoretical values and at a final pH greater than 8.0. The removals of Cd, Zn, and Cu from the actual wastewaters are greater than 99%, and As and Se removals are 98 and >92%, respectively. Cd, Cu, and Zn concentrations in the range of 0.05 to 0.1 mg/1 can be achieved with sulfide precipitation. The metal separations and settling rates obtained with conventional hydroxide precipitation (lime) are considerably lower than those obtained with sulfide precipitation.

? Varshney, K.G., Sharma, U., Rani, S. and Premadas, A. (1982), Cation-exchange study on a crystalline and thermally stable phase of antimony silicate. effect of irradiation on ion-exchange behavior and separation of Cd(II) from Zn(II) and Mn(II) and of Mg(II) from Ba(II), Ca(II), and Sr(II). Separation Science and Technology, 17 (13-14), 1527-1543.

Full Text: 1982\Sep Sci Tec17, 1527.pdf

Abstract: A systematic ion-exchange study has been performed on antimony silicate, which includes its ion-exchange capacity, elution behavior, pH titrations, and distribution coeflicients of common metal ions. The Kd values for alkali metals vary with the pH of the solution and the material is found to be highly selective for Rb(I) at pH values greater than 1. On the basis of distribution studies, the separation of Cd(II) from Zn(II) and Mn(II) has been achieved. Similarly, Mg(II) has been separated from Ba(II), Ca(II), and Sr(II) to illustrate its utility. Antimony silicate is very stable both thermally and chemically and possesses reproducible ion-exchange properties, also, the effect of irradiation on the ion-exchange behavior is negligible. A tentative formula of the material has also been proposed based on chemical, infrared, and thermogravimetric analysis studies, The x-ray studies reveal that the exchanger is crystalline with a d-value of 6.09Å.

Yenkie, M.K.N. and Natarajan, G.S. (1991), Adsorption equilibrium studies of some aqueous aromatic pollutants on granular activated carbon samples. Separation Science and Technology, 26 (5), 661-674.

Full Text: 1991\Sep Sci Tec26, 661.pdf

Abstract: Adsorption equilibrium studies of some aromatic organic pollutants in water with some commercially available standard grades of granular activated carbons have been carried out at 35C. The adsorption equilibrium data for adsorbates such as phenol, aniline, benzoic acid, o-cresol, and p-methoxyphenol on six grades of granular activated carbons were analyzed for their adherence to Freundlich or Langmuir adsorption isotherms, and the results are discussed.

? Kawakita, T., Matsuishi, T. and Koga, Y. (1991), Optimization of lysine adsorption process using strong cation- exchange resin. Separation Science and Technology, 26 (6), 869-883.

Full Text: 1991\Sep Sci Tec26, 869.pdf

Abstract: A simplified method is proposed for determining the optimum conditions of multicolumn adsorption of lysine from a lysine fermentation broth, in which the resin columns periodically move countercurrent to a continuous broth flow. Experimental data on dynamic isotherms in the fixed-bed column are required for the calculations. The recurrence equation involved was solved on a personal computer. Based on this model, the optimum operation conditions of lysine adsorption were determined in order to minimize the production cost of lysine recovery from lysine fermentation broth.

Keywords: Adsorption, Column, Fermentation, Fixed Bed, Fixed Bed Column, Fixed-Bed, Fixed-Bed Column, Isotherms, Model, Recovery

? Fujita, I., Nagano, Y., Haratake, M., Harada, K., Nakayama, M. and Sugii, A. (1991), Adsorption of nonionic surfactants on chemically modified styrene divinylbenzene copolymers. Separation Science and Technology, 26 (10-11), 1395-1402.

Full Text: 1991\Sep Sci Tec26, 1395.pdf

Abstract: Two series of resins with both polar and nonpolar regions were synthesized by the introduction of alpha-oxoalkyl and alpha-hydroxyalkyl groups to a porous low crosslinked styrene-divinylbenzene (7.5% divinylbenzene). These resins showed higher adsorption capacity for polyoxvethylene-type nonionic surfactants than did the starting resin. Resins with shorter alkyl chains are particularly more effective than those with longer chains. It is suggested that the polar groups on the modified resins contribute to the increase in adsorption of the surfactants.

Keywords: Adsorption, Adsorption Capacity, Capacity, Modified, Porous, Resins, Surfactants

Saleem, M., Afzal, M., Qadeer, R. and Hanif, J. (1992), Selective adsorption of uranium on activated-charcoal from electrolytic aqueous solutions. Separation Science and Technology, 27 (2), 239-253.

Full Text: 1992\Sep Sci Tec27, 239.pdf

Abstract: Adsorption of uranium on activated charcoal has been studied as a function of shaking time, amount of adsorbent, pH, concentration of adsorbate, and temperature. Uranium adsorption obeys the Langmuir isotherm. DELTA-H-degrees and DELTA-S-degrees were calculated from the slope and intercept of plots of ln K(D) vs 1/T. The influence of different anions and cations on uranium adsorption has been examined. The adsorption of other metal ions on activated charcoal has been studied under specified conditions to check its selectivity, consequently, uranium was removed from Cs, Ba, Zn, and Co. More than 98% adsorbed uranium on activated charcoal can be recovered with 65 mL of 3 M HNO₃ solution. A wavelength dispersive x-ray fluorescence spectrometer was used for measuring uranium concentration.

Keywords: Zirconium

? Garciadelgado, R.A., Cotoruelominguez, L.M. and Rodriguez, J.J. (1992), Equilibrium study of single-solute adsorption of anionic surfactants with polymeric XAD resins. Separation Science and Technology, 27 (7), 975-987.

Full Text: 1992\Sep Sci Tec27, 975.pdf

Abstract: Equilibrium data for the adsorption of sodium lauryl sulfate (SLS) and sodium dodecylbenzene sulfonate (SDBS) from aqueous solutions by Amberlite XAD-4 and XAD-7 polymeric resins at temperatures in the 10-40°C range have been obtained. The specific surface area of the resins plays a major role in adsorption, and thus the best results have been obtained with XAD-4 resin. A higher adsorption of SDBS over SLS was also observed. Several adsorption isotherm models have been used to fit the experimental data. The best results have been obtained with the Redlich-Peterson and Langmuir-Freundlich equations. Estimations of the isosteric heat of adsorption, free energy, and entropy of adsorption are also reported.

KeyWords: Isotherms

? Bhandari, V.M., Juvekar, V.A. and Patwardhan, S.R. (1992), Modified Shrinking Core Model for Reversible Sorption on Ion-Exchange Resins. Separation Science and Technology, 27 (8-9), 1043-1064.

Full Text: 1992\Sep Sci Tec27, 1043.pdf

Abstract: A modified shrinking core model is proposed to correlate dynamics of acid sorption on weak base ion-exchange resins in free base form. The model considers reversibility of the sorption process which is ignored in the conventional shrinking core model. The model is easy to apply and is shown to yield results which are in agreement with a computationally intensive rigorous model. The model is successfully verified using the experimental data on sorption of strong acids (HCI and HNO3) on weak base resins (Dowex WGR-2 and Amberlite IRA-93).

Keywords: Acid Sorption, Acids, Dynamics, HNO₃, Ion Exchange, Kinetics, Model, Modeling, Modified, Resins, Shrinking Core Model, Sorption, Weak Base Resin, Yield

Rajaković, L.V. (1992), The sorption of arsenic onto activated carbon impregnated with metallic silver and copper. Separation Science and Technology, 27 (11), 1423-1433.

Full Text: 1992\Sep Sci Tec27, 1423.pdf

Abstract: The adsorption of arsenic species in aqueous solutions onto activated carbon with and without chemical impregnation has been studied. The ability of activated carbon to adsorb arsenic depends on the arsenic oxidation state, the pH of the water, and the activity of the metal used for the activated carbon impregnation. The results of the investigations have shown that physical adsorption is effective only for the arsenic(V) species in water. Activated carbon adsorbs arsenic(V) with a saturation adsorption capacity of 0.27 mmol/g. The chemisorption process is effective for both arsenic species. By impregnation of activated carbon by copper, the sorption process for the arsenic(III) species is significantly improved. The saturation adsorption capacity of the activated carbon impregnated by copper is 0.41 and 0.23 mmol/g for the arsenic(III) and arsenic(V) species, respectively. The pH values of the water are important for both sorption processes because of the change in the ionic forms of both arsenic species. The optimal pH range is between 4 and 9, which is a consequence of the apparent affinity between the carbon surface and arsenic species H₃AsO₃ and H₂AsO₄^-that are predominant at this pH in water. Equilibrium isotherm analyses were undertaken using Langmuir and Freundlich equations.

Keywords: Adsorption, Activated Carbon, Impregnation, Water Pollution, Equilibrium Isotherms, Arsenic, Copper, Removal, Adsorption, Idaho

Hasany, S.M. and Saeed, M.M. (1992), A kinetic and thermodynamic study of silver sorption onto manganese-dioxide from acid-solutions. Separation Science and Technology, 27 (13), 1789-1800.

Full Text: 1992\Sep Sci Tec27, 1789.pdf

Abstract: The batch kinetics of silver sorption at the tracer level onto manganese dioxide along with the thermodynamic parameters from dilute nitric and perchloric acid solutions are described. The values of DELTA-H, DELTA-S, and DELTA-G found from both acid solutions are similar. The sorption equilibrium constant, K(C), has been calculated at different temperatures between 288 and 308 K. Tests of different isotherms have shown that the sorption data fit very well to the Freundlich and Dubinin-Radushkevich (D-R) models at different temperatures. The thermodynamic data indicate the endothermic nature of silver sorption onto the oxide. The sorption capacity in the 0.23-0.77 mmol/g range and a mean free energy of sorption of about 11.5-15.4 kJ/mol have been found by using the D-R approach. The values of B and the correlation factor (r) have been determined by using the D-R isotherm. These values are comparable with those reported earlier for other sorption systems.

Keywords: Kinetics, Thermodynamics, Silver, Sorption, Manganese Dioxide, Acid Solutions, Adsorption, Microamounts

? Reed, B.E. and Matsumoto, M.R. (1993), Modeling cadmium adsorption by activated carbon using the Langmuir and Freundlich isotherm expressions. Separation Science and Technology, 28 (13-14), 2179-2195.

Full Text: 1993\Sep Sci Tec28, 2179.pdf

Abstract: Cadmium adsorption isotherms were conducted using two commercially available powdered activated carbons (PACs). Isotherms were conducted at several pH values and metal and carbon concentrations. Both PACs removed significant amounts of cadmium, and removal was a strong function of solution pH: increasing the solution pH increased cadmium adsorption. Adsorption data at a specific pH were successfully modeled using both the Langmuir and Freundlich isotherms. Adsorption and surface precipitation were hypothesized to be the operative removal mechanisms. Cadmium removal is strongly related to the carbon’s pH_ZPC, acid-base characteristics, and surface charge-pH relationship, Surface area, an important adsorption parameter for organic adsorbates, does not appear to influence metal removal strongly.

Keywords: Surface-Acidity, Heavy-Metals

Reed, B.E. and Cline, S.R. (1994), Retention and release of lead by a very fine sandy loam. I. Isotherm modeling. Separation Science and Technology, 29 (12), 1529-1551.

Full Text: 1994\Sep Sci Tec29, 1529.pdf

Abstract: The retention of lead by a very fine sandy loam was investigated. Aqueous lead concentrations between 10 and 1000 mg/L and soil concentrations ranging from 10 to 167 g/L were used. Lead retention by the soil was a strong function of pH. The width of the pH-adsorption edge decreased with increasing lead concentration. Experimental results were modeled using the Langmuir, Freundlich and BET isotherms. Only the Langmuir and Freundlich isotherms successfully represented the experimental results. The role of surface precipitation was assumed to be small because of the failure of the BET isotherm to adequately predict metal retention. The Freundlich isotherm provided the best fit because a maximum surface concentration was usually not observed. Langmuir and Freundlich isotherms parameters varied in a way that suggested that the average binding energy and the distribution of bond strengths increased with increasing pH. The isotherm expressions determined in this study can be used as source-sink terms in the generalized mass transport model.

Keywords: Heavy-Metals, Adsorption, Soils, Extraction, Interface, Sorption, Cadmium, Oxides, Ions, Cd

? Muraleedharan, T.R., Venkobachar, C. and Leela, I. (1994), Investigations of fungal fruiting bodies as biosorbents for the removal of heavy-metals from industrial processing streams. Separation Science and Technology, 29 (14), 1893-1903.

Full Text: 1994\Sep Sci Tec29, 1893.pdf

Abstract: The revival of interest in biotechnology has fueled research in many sectors of environmental biotechnology. The present paper describes research utilizing adsorbents prepared from wood-rotting mushrooms growing wild in tropical forests. Nine species of mushrooms were screened using copper(II) as the model adsorbate. While may species showed excellent potential, comparable to biosorbents reported in literature, Ganodernma lucidum emerged as the best biosorbent. This biosorbent was further developed for use in a packed-bed bioreactor for treatment of rare earth processing effluents. Electron paramagnetic studies confirmed that adsorption is by chemical binding to the biosorbent.

Keywords: Biosorption, Wood-Rotting Mushrooms, Rare Earth Industry, Ganoderma Lucidum, Electron Paramagnetic Resonance, Biomass, Ions

Saeed, M.M., Rusheed, A., Ahmed, N. and Tölgyessy, J. (1994), Extraction and adsorption behavior of Co(II) on HTTA-impregnated polyurethane foam. Separation Science and Technology, 29 (16), 2143-2160.

Full Text: 1994\Sep Sci Tec29, 2143.pdf

Abstract: The batch extraction of Co(II) from aqueous solutions with open cell polyether-type HTTA-loaded polyurethane (PU) foam has been studied using a radiotracer technique. The effect of pH, shaking time, and loading capacity has been investigated. The membrane properties of loaded PU foam sorbent offer unique advantage of adsorption. The fundamental studies of adsorption show that the classical Freundlich and Langmuir isotherms are followed in the entire concentration range of a 10^-5 to 10^-2 M solution of cobalt. The sorption mean free energy from the Dubinin-Radushkevich isotherm is found to be 13.8 kJ.mol^-1 and the loading capacity 4.44 mg.g^-1, suggesting that the ion-exchange or chemisorption mechanism operates. The kinetic parameters of adsorption also support a chemisorption mechanism and the first-order rate law. The rate constants and activation energies of sorption and desorption have been evaluated. The thermodynamic function of adsorption of DELTAH, DELTAS, DELTAG, and equilibrium constant K(C) have been calculated. The process of adsorption is established to be endothermic and chemisorption, stabilized through thermodynamic functions.

Keywords: Activation, Adsorption, Aqueous Solutions, Batch, Capacity, Chemisorption, Co(II), Cobalt, Concentration, Delta, Desorption, Endothermic, Energy, Equilibrium, Extraction, First Order, Foam, Freundlich, Function, Functions, Ion Exchange, Ion-Exchange, Ionexchange, Isotherm, Isotherms, Kinetic, Kinetic Parameters, Langmuir, Langmuir Isotherms, Law, Loading, Mechanism, Membrane, Open, pH, Polyurethane, Pre-Concentration Methods, PU, Radiotracer, Radiotracer Technique, Rate Constants, Rate Law, Ray-Fluorescence Spectrometry, Solution, Solutions, Sorbent, Sorption, Support, Thermodynamic, Thermodynamic Functions, Trace-Elements, Water

Reed, B.E. (1995), Identification of removal mechanisms for lead in granular activated carbon (GAC) columns. Separation Science and Technology, 30 (1), 101-116.

Full Text: 1995\Sep Sci Tec30, 101.pdf

Abstract: In an earlier study the removal of lead by a granular activated carbon (GAC) column was increased by over 600% when the carbon [Hydrodarco 4000 (HD4000), Norit Americas, Inc.] was contacted with a 0.1 N HNO₃-0.1 N NaOH rinse. Hypothesized removal mechanisms were adsorption, surface preceipitation and pore precipitation. In this work a series of experiments were conducted on samples of the virgin and acid-base rinsed carbon to determine their acid-base behavior, pH_zpc and Pb removal ability. If adsorption was a dominant removal mechanism, then significant differences in these parameters for the virgin and acid-base rinsed carbons would be expected. The strong acid-base rinse did not significantly alter the acid-base behavior, pH_zpc, or the Pb removal ability compared to virgin HD4000. Thus, it appears that the dramatic increase in metal removal by the regenerated GAC columns was not caused by an increase in the number or type of adsorption sites but was due to the precipitation of Pb on the carbon surface or in the carbon pore liquid. Future research efforts will focus on the modeling of Pb removal in GAC columns using precipitation as the primary removal mechanism.

Keywords: Adsorption

Van Deventer, J.S.J. and Van Der Merwe, P.F. (1995), Kinetic model for the decomposition of cyanide during the elution of gold from activated carbon. Separation Science and Technology, 30 (6), 883-898.

Full Text: 1995\Sep Sci Tec30, 883.pdf

Abstract: Free cyanide is usually present during the elution of gold cyanide from activated carbon. The decomposition of cyanide is important not only in the extraction of gold but also for environmental reasons. Previous studies have indicated that competitive adsorption of cyanide with aurocyanide plays a minor role at the elevated temperatures used in industry. A more important effect of cyanide is its decomposition reaction with functional groups on the carbon, the products of which passivate the surface for adsorption of aurocyanide and thereby cyanide appears to enhance the elution of aurocyanide. It was observed that the degree of passivation affects the elution of gold and the degradation/adsorption of cyanide itself. Batch tests have shown that the rate of oxidation of cyanide at low temperatures is independent of particle size and more dependent on film transfer. Based on these observations, a kinetic model was proposed for the decomposition and elution of cyanide in packed columns of activated carbon. The oxidation and hydrolysis reactions in the bulk solution, as well as in the carbon pores, were combined and described by single first-order reactions. It was found that the same kinetic parameters could be used to give satisfactory predictions of experimental data for a wide range of conditions.

Keywords: Electrochemical Destruction, Chemical Behavior, Extraction

? Kim, K.R., Lee, K.J. and Bae, J.H. (1995), Characteristics of cobalt adsorption on prepared TiO₂ and Fe-Ti-O adsorbents in high-temperature water. Separation Science and Technology, 30 (6), 963-979.

Full Text: 1995\Sep Sci Tec30, 963.pdf

Abstract: TiO₂ and Fe-Ti-O adsorbents were prepared by hydrolysis of Ti(OC₃H₇)₄ and by alkalizing an equimolar mixed solution of TiCl₄ and FeCl₂, followed by heat treatment of their hydroxides. Their structures were studied by x-ray diffractometry and TG-DTA. The Co²⁺ adsorption characteristics of the adsorbent in high temperature water were investigated in a stirred autoclave. The prepared Fe-Ti-O adsorbent was found to be a stable nonstoichiometric ferrous/ferric titanium oxide with pseudobrookite and rutile structures. The Co-Z⁺ adsorption capacity of the Fe-Ti-O adsorbent was determined to be larger (0.38 meg Co²⁺/g adsorbent at 280°C) than that of TiO₂ at high temperature. The enthalpy changes (H°) of about 34 and 49 kJ . mol^-1 due to the adsorption of Co-Z⁺ on the TiO₂ and Fe-Ti-O adsorbents, respectively, indicates that the adsorption is endothermic in the experimental temperature range (150-280C). It is shown that the specific surface areas of these adsorbents are not dominant factors for Co²⁺ adsorption on oxides at high temperature.

Keywords: Titanium-Oxide, Removal

? Periasamy, K. and Namasivayam, C. (1995), Adsorption of Pb(II) by peanut hull carbon from aqueous solution. Separation Science and Technology, 30 (10), 2223-2237.

Full Text: 1995\Sep Sci Tec30, 2223.pdf

Abstract: Carbon prepared from peanut hulls (PHC) has been used for the adsorption of Pb(II) over a range of initial metal ion concentrations (10-20 mg/L), agitation times (5-140 minutes), adsorbent dosages (5-100 mg/100 mt) and pH values (1.5-10.0). Adsorption of Pb(II) obeyed the Langmuir isotherm. The applicability of the Lagergren kinetic model has also been investigated. Quantitative removal of 20 mg/L Pb(II) by 0.3 g carbon per liter aqueous solution was observed in the pH range of 3.0 to 10.0. A comparative study with a coal-based commercial granular activated carbon (CAC) showed that the adsorption capacity of PHC was 18 times larger than that of CAC.

Keywords: Activated Carbon, Removal, Equilibrium, Water, Clay

? Inoue, K., Yamaguchi, T., Iwasaki, M., Ohto, K. and Yoshizuka, K. (1995), Adsorption of some platinum-group metals on some complexane types of chemically-modified chitosan. Separation Science and Technology,