Cadmium and zinc uptake by dried activated sludge: Equilibrium and experimental design study

Removal of Cd2+ and Zn2+ ions from single and binary solutions by dried activated sludge was studied in batch experiments. It was shown that the metal removal is a rapid process significantly influenced by solution pH. Maximum uptake of both Cd and Zn was reached at pH 6.0 and negligible uptake was observed at pH 2.0. The Langmuir isotherm was found to well represent the measured equilibrium sorption data in single metal systems and the maximum sorption capacities Qmax of the activated sludge (d.w.), calculated from Langmuir model were 540 ± 16 μmol/g for Zn2+ and 510 ± 17 μmol/g for Cd2+ ions. The Response surface methodology (RSM) was used for investigation of interaction and competitive effects in binary metal system. It was found that dried activated sludge in binary system Cd-Zn has slightly higher affinity for Cd2+ comparing with Zn2+ ions. Competitive effect of Cd on Zn uptake increased with increasing solution pH and Cd initial concentration. Maximum sorption capacities of the activated sludge were 321 μmol Cd2+/g and 312 μmol Zn2+/g. RSM appears to be a better tool for the evaluation of interaction and competitive effects in binary systems than both the simple extrapolation from single-component systems and experimentally difficult study of multi-component systems.

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Sorption of cobalt and zinc from single and binary metal solutions by Evernia prunastri

Nova Biotechnologica et Chimica ◽

10.36547/nbc.1355 ◽

2022 ◽

Vol 7 (1) ◽

pp. 23-31

Author(s):

Martin Pipíška ◽

Miroslav Horník ◽

Ľuboš Vrtoch ◽

Soňa Šnirclová ◽

Jozef Augustín

Keyword(s):

Binary Systems ◽

Three Dimensional ◽

Terrestrial Ecosystems ◽

Evernia Prunastri ◽

Sorption Data ◽

Sorption System ◽

Freundlich Isotherms ◽

Binary Metal ◽

Cobalt Removal ◽

Maximum Sorption

Non-living lichen Evernia prunastri was studied as biosorbent material for zinc and cobalt removal from single and binary metal solutions. Sorption equilibrium of Zn2+ and Co2+ ions was reached within 1 hour. Both cobalt and zinc biosorption was not pH dependent within the range pH 4-6 and negligible at pH 2. The experimental results were fitted to the Langmuir, Freundlich, Redlich-Peterson and Langmuir-Freundlich adsorption isotherms to obtain the characteristic parameters of each model. The Langmuir, Redlich-Peterson and Langmuir-Freundlich isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the maximum sorption capacities of metal ions onto lichen biomass were 112 μmol/g Zn and 97.2 μmol/g Co from single metal solutions. E. prunastri exhibited preferential uptake of zinc from equimolar binary Zn2+ - Co2+ mixtures within the range 50 – 4000 μM. Even thought mutual interference was seen in all Co-Zn binary systems. To evaluate the two-metal sorption system, simple curves had to be replaced by three-dimensional sorption surface. These results can be used to elucidate the behavior of lichens as bioindicators of cobalt and zinc pollution in water and terrestrial ecosystems.

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Removal of Pb2+ ions from aqueous solution by P(HEA/IA) hydrogels

Hemijska industrija ◽

10.2298/hemind151225006a ◽

2016 ◽

Vol 70 (6) ◽

pp. 695-705 ◽

Cited By ~ 3

Author(s):

Katarina Antic ◽

Marija Babic ◽

Jovana Vukovic ◽

Antonije Onjia ◽

Jovanka Filipovic ◽

...

Keyword(s):

Significant Loss ◽

Isotherm Models ◽

Order Model ◽

Solution Ph ◽

Sorption Data ◽

Maximum Sorption ◽

Pseudo Second Order ◽

Adsorption Desorption ◽

Best Fit ◽

Sorbent Weight

A series of poly(2-hydroxyethyl acrylate-co-itaconic acid), P(HEA/IA), hydrogels with different HEA/IA ratio, were synthesized using free radical crosslinking/copolymerization and investigated as sorbents for Pb2+ ions from aqueous solutions. Hydrogels were characterized using DMA, FTIR, DSC, SEM and AFM. The adsorption was found to be highly dependent on hydrogel composition, solution pH, sorbent weight, ionic strength and contact time. Five isotherm models, Langmuir, Freundlich, Redlich-Peterson, Temkin and Dubinin-Radushkevich, were applied to the sorption data. The best fit was obtained with Redlich-Peterson isotherm. The separation factor, RL, value indicated favorable sorption for Pb2+ ions. The maximum sorption capacities were 392.2 and 409.8 mg/g for P(HEA/2IA) and P(HEA/10IA), respectively. Kinetic data showed best fit with pseudo-second-order model. Thermodynamic studies revealed that the reaction was exothermic and proceeds with a decrease in entropy. Moreover, P(HEA/IA) hydrogel showed the most pronounced sorption toward Pb2+ ions from environment containing Cu2+, Zn2+, Cd2+, Ni2+ and Co2+ ions. Sorption/desorption experiments, showed that the P(HEA/IA) hydrogels could be reused without significant loss of the initial properties even after three adsorption-desorption cycles.

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Sorption Profile and Thermodynamic Characteristics of Nitrosonaphthol Functionalized Sorbent for Metal Ion Enrichment

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20051341 ◽

2005 ◽

Vol 70 (9) ◽

pp. 1341-1356 ◽

Cited By ~ 1

Author(s):

Saima Q. Memon ◽

Muhammad I. Bhanger ◽

Muhammad Y. Khuhawar

Keyword(s):

Metal Ion ◽

Tap Water ◽

Thermodynamic Characteristics ◽

Chelating Agent ◽

Standard Addition ◽

Absorption Spectrometry ◽

Sorption Data ◽

Maximum Sorption ◽

Styrene Divinylbenzene ◽

Two Phases

A simple and reliable method has been developed using styrene-divinylbenzene-based polymeric material containing 1-nitroso-2-naphthol as chelating agent, to concentrate ultratrace amounts of Ni(II) and Cu(II) ions in aqueous samples. Sorption of both the ions on the new synthetic resin under static and dynamic conditions has been investigated. The sorption has been optimized with respect to pH, shaking and contact time of two phases. Maximum sorption has been achieved from solution of pH 5-8 after 8 min of agitation. Total saturation capacities were 516 ± 2 and 316 ± 2.5 μmol g-1 for Ni(II) and Cu(II) ions, respectively. The lowest concentration for quantitative recovery (98 ± 1%) is 1.33 and 5 ppb with the preconcentration factor of 750 and 200 for Ni(II) and Cu(II), respectively. Monitoring of the influence of diverse ions on the sorption of metal ions has revealed that phosphate, hydrogencarbonate and citrate reduce the sorption to some extent. Under optimum conditions the sorption data followed Langmuir, Freundlich, and Dubinin-Radushkevich isotherms. The kinetics and thermodynamics of sorption are studied in detail. The sorption procedure is utilized to preconcentrate these ions prior to their determination in tea, human hair, and tap water samples by atomic absorption spectrometry using direct and standard addition methods.

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Mechanism of Metal Removal in Activated Sludge

Journal of Environmental Engineering ◽

10.1061/(asce)0733-9372(1987)113:5(1074) ◽

1987 ◽

Vol 113 (5) ◽

pp. 1074-1088 ◽

Cited By ~ 8

Author(s):

Tom Stephenson ◽

Patricia S. Lawson ◽

Thomasine Rudd ◽

Robert M. Sterritt ◽

John N. Lester

Keyword(s):

Activated Sludge ◽

Metal Removal

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Concentration Dependence of the Surface Tension of Three and Four-Component Systems with Peculiarities in the Surface Tension Isotherms of Lateral Binary Melts

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1022.194 ◽

2021 ◽

Vol 1022 ◽

pp. 194-202

Author(s):

R.Kh. Dadashev ◽

R.A. Kutuev

Keyword(s):

Experimental Data ◽

Surface Tension ◽

Concentration Dependence ◽

Experimental Error ◽

Binary Systems ◽

Experimental Studies ◽

Study Results ◽

Component Systems ◽

Minimum Depth ◽

Surface Tension Isotherms

The experimental study results of the melts concentration dependence of the surface tension of the four-component indium-tin-lead-bismuth system and its constituent binary systems of indium-tin, indium-lead, indium-bismuth, tin-lead, tin-bismuth, lead-bismuth are presented in the paper. It is shown that the concentration dependence of the melts surface tension of the In-Sn-Pb-Bi four-component system can be predicted from the data on ST (surface tension) values of lateral binary systems. Features in the ST isotherms in the form of a minimum are observed only in the indium-tin lateral system from all lateral binaries. A distinctive feature of the detected minimum is that the minimum depth slightly exceeds the experimental error. Therefore, in addition to the fact that the area of average compositions was studied more thoroughly, we carried out the surface tension measurements by two independent methods. The experimental data obtained by both methods coincide within the experimental error and indicate the extremum availability on ST isotherms. Thus, ST experimental studies by two independent methods confirmed the presence of a flat minimum on ST isotherms of the indium-tin binary system increasing the reliability of the obtained data. The obtained outcomes and their comparison with experimental data have shown that the considered models for predicting surface properties based on data due to similar properties of lateral binary systems adequately reflect the experimental dependences. However, the prediction model based on Kohler's method of excess values describes the experimental curves more accurately.

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Biosorption of Cadmium by Fucus spiralis

Environmental Chemistry ◽

10.1071/en04039 ◽

2004 ◽

Vol 1 (3) ◽

pp. 180 ◽

Cited By ~ 74

Author(s):

Manuel Esteban Sastre de Vicente ◽

Roberto Herrero ◽

Pablo Lodeiro ◽

Bruno Cordero

Keyword(s):

Heavy Metals ◽

Metal Removal ◽

Heavy Metal Removal ◽

Biological Materials ◽

Ion Concentration ◽

Adsorption Parameters ◽

Solution Ph ◽

Biosorption Process ◽

Fucus Spiralis ◽

Biosorption Kinetics

Environmental Context. Conventional processes for the removal of heavy metals from wastewaters generally involves chemical precipitation of metals (changing the pH) followed by a period to allow the metal precipitates to settle and be separated. These processes are inefficient when the metals are at a low concentration and still demand handling and disposal of toxic metal sludges. An alternative method for heavy metal removal is adsorption onto a biological material, biosorption. The biological materials, including agricultural byproducts, bacteria, fungi, yeast, and algae, all which take up heavy metals in substantial quantities, are relatively inexpensive, widely available, and from renewable sources. However, biological materials are complex and the active mechanisms often unclear. Abstract. Cadmium biosorption properties of nonliving, dried brown marine macroalga Fucus spiralis from Galician coast (northwest Spain) have been investigated. The biosorption capacity of the alga strongly depends on solution pH; the uptake is almost negligible at pH ≤ 2 and reaches a plateau at around pH 4.0. Cadmium biosorption kinetics by F. spiralis is relatively fast, with 90% of total adsorption taking place in less than one hour. A pseudo second order mechanism has been proved to be able to predict the kinetic behaviour of the biosorption process. The effect of initial cadmium ion concentration, alga dose, solution pH, and temperature on the biosorption kinetics has been studied. The Langmuir, Freundlich, Langmuir–Freundlich, and Tóth isotherms were used to fit the experimental data and to find out the adsorption parameters. Acid–base properties of the alga have been studied potentiometrically in order to calculate the number of acidic groups and the apparent pK value by using Katchalsky model. The pK obtained is comparable with typical values associated to the ionization of carboxyl groups of alginates, supporting the implication of these groups in the biosorption process.

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Valorization of Uncharred Dry Leaves of Ficus benjamina towards Cr (VI) removal from Water: Efficacy Influencing Factors and mechanism

Scientific Reports ◽

10.1038/s41598-019-55993-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Preeti S. Kulkarni ◽

Varuna S. Watwe ◽

Abubakar J. Hipparge ◽

Sana I. Sayyad ◽

Rutika A. Sonawane ◽

...

Keyword(s):

Influencing Factors ◽

Maximum Adsorption Capacity ◽

Equilibration Time ◽

Aqueous Samples ◽

Sorption Data ◽

Maximum Sorption ◽

Pseudo Second Order ◽

Ft Ir ◽

Better Than ◽

Work Treatment

AbstractThe potential of uncharred biomaterial derived from dry leaves of Ficusbenjamina (Family: Moraceae,local name: Weeping Fig) plant to remove Cr(VI) from aqueous samples was investigated. In the present work, treatment of dilute acids was used for activating the adsorption centres on the biomass instead of cumbersome charring process. The plant material was characterized using FT-IR, FE-SEM and EDX. Various influencing factors such as pH of equilibrating solution, contact time, Cr (VI) concentrations, adsorbent dose and temperature were optimized to obtain maximum sorption efficacy. The interactions among the biomaterial and Cr (VI) in water were studied by fitting the sorption data in four different adsorption isotherms. The data fitting and experimental evidences indicated formation of monolayer of Cr(VI) over the biomass surface. The process followed pseudo-second order kinetics and was thermodynamically spontaneous under laboratory conditions and reached equilibrium in 24 hours. Maximum adsorption capacity of 56.82 mg/g was obtained at the pH 2 when the concentration before adsorption was 200 mg L−1 of Cr(VI) with 24 hours of equilibration time and 2.50 g L−1 of dose of biomaterial at room temperature. The sorption efficiency was found to be better than many charred bio-based materials.

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On the mechanism of benzene and toluene adsorption in single-compound and binary systems: energetic interactions and competitive effects

10.5004/dwt.2017.20712 ◽

2017 ◽

Vol 86 ◽

pp. 259-265 ◽

Cited By ~ 13

Author(s):

A. Erto ◽

◽

S. Chianese ◽

A. Lancia ◽

D. Musmarra

Keyword(s):

Binary Systems ◽

Competitive Effects ◽

Single Compound ◽

Energetic Interactions

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Removal of Strontium Ions from Aqueous Solution by Sunflower Straw

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.726-731.1922 ◽

2013 ◽

Vol 726-731 ◽

pp. 1922-1925 ◽

Cited By ~ 1

Author(s):

Lian Ai ◽

Xue Gang Luo ◽

Xiao Yan Lin ◽

Si Zhao Zhang

Keyword(s):

Aqueous Solution ◽

Batch Adsorption ◽

Order Model ◽

Solution Ph ◽

Sorption Data ◽

Freundlich Model ◽

Pseudo Second Order ◽

Ft Ir ◽

Sunflower Straw ◽

Langmuir And Freundlich Models

The sorptive potential of sunflower straw (≤125 μm) for Sr2+ from aqueous solution was evaluated. Batch adsorption experiments were carried out as a function of solution pH, adsorbent dosage, Sr2+ concentration and contact time. FT-IR spectra and SEM of sunflower straw were employed to explore the functional groups available for the binding of Sr2+ and morphology of the adsorbent. Maximum uptake capacity of sunflower straw was 17.48 mg/g occurred at around pH 3-7. The adsorption equilibrium can be achieved within 5 min and kinetic data were fitted well to pseudo-second-order model. The Langmuir and Freundlich models were applied to describe isotherm sorption data. The Langmuir model gave an acceptable fit than Freundlich model.

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