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1.
Environ Res ; 258: 119430, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38885826

RESUMEN

A silica gel-modified borage biochar (BB@Si) was first produced and used as a binding agent for potentially hazardous Ni2+ ions in aqueous systems. The recommended biochar was more effective in eliminating Ni2+ than pristine biochar (BB). Its maximum qm could reach up to 1.39 × 10-3 mol/g at 30 °C, and sorption isotherms showed that the Langmuir model could more accurately define its sorption behavior. The Dubinin-Radushkevich isotherm also revealed that the average sorption energy ranged from 11.00 to 11.14 kJ/mol. Zeta potential tests, SEM images, and FT-IR scans confirmed the interactions between BB@Si and Ni2+ ions. Dynamic flow treatment studies showed high uptake effectiveness when the flow rate and amount of BB@Si were suitable. Nickel desorption yield of around 80% from BB@Si was noted with 0.01 M HCl. The BB@Si column's breakthrough and exhausted points were identified to be 45 and 352 min, respectively. Its maximum exhaustion capacity value was determined to be 52.73 mg/g. Ni2+ removal from the actual wastewater sample exceeded 75%. The resulting outcomes imply the immense potential of employing BB@Si in the treatment of Ni2+- contaminated aqueous systems.


Asunto(s)
Carbón Orgánico , Níquel , Contaminantes Químicos del Agua , Níquel/química , Níquel/análisis , Carbón Orgánico/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Adsorción , Purificación del Agua/métodos
2.
Environ Sci Pollut Res Int ; 31(17): 25836-25848, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38488918

RESUMEN

Biosorptive treatment with microbial biomass is regarded as an environmentally friendly and effective way to reduce dye contamination in contaminated aquatic environments. Immobilizing microbial cells for use in this process can significantly improve their effectiveness as biosorbents in the water treatment process. The current investigation searches for a sustainable and environmentally friendly approach to decolorization by employing a green biocomposite material sorbent system (ZM@GFC) created by immobilizing fungal cells (Gibberella fujikuroi) on maize tassel tissues to efficiently remove Reactive Yellow 2 (RY2) from contaminated water sources. Batch and dynamic flow tests were performed to evaluate the biodecolorization properties of the newly created immobilized biomaterial as well as the effects of several essential operating conditions factors on the sorption behavior. Biosorption yields of 95.7% and 90.0% in batch and dynamic modes were achieved for experimental dye decolorization. The biosorption of RY2 by ZM@GFC occurred fast and achieved equilibrium within 60 min. The pseudo-second-order kinetic model elucidated the dye biosorption onto ZM@GFC. The Langmuir model provided a more accurate representation of the results than the Freundlich model. At the same time, Redlich-Peterson isotherm demonstrated the best level of agreement with the experimental data. These findings indicate that the biosorption mechanism predominantly involved the formation of a monolayer covering and that the energy properties of the ZM@GFC surface were uniform. The breakthrough capacity at the exhaustion time was 537.32 mg g-1. The predicted cost of generating ZM@GFC was anticipated to be 61.03 USD/kg. The investigations on safe disposal demonstrated that the biosorption process did not generate any secondary pollution. In conclusion, using maize tassel tissue as an immobilized decolorization agent offers a possible method for removing reactive azo dye pollutants from the aquatic medium that is both economical and environmentally benign.


Asunto(s)
Fusarium , Contaminantes Químicos del Agua , Zea mays , Biodegradación Ambiental , Descontaminación , Inflorescencia , Termodinámica , Cinética , Adsorción , Concentración de Iones de Hidrógeno , Biomasa
3.
Int J Biol Macromol ; 221: 865-873, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36063895

RESUMEN

Immobilized biomaterials have recently attracted researchers' attention in the field of environmental biotechnology due to their effective biosorption performances. In this respect, a novel hybrid biocomposite based on Thamnidium elegans cells, olive pomace, and chitosan (TE-OP@C) was produced and tested for the first time to remove a target pollutant. It was successfully employed to eliminate toxic Cu(II) ions. Uptake efficiency of the biocomposite was significantly greater than that of T. elegans and T. elegans-olive pomace, despite the much lesser amount of biocomposite used. Freundlich model best fitted the equilibrium data, and the pseudo-second-order kinetic model followed Cu(II) uptake. The maximum removal efficiencies in batch and continuous systems were determined to be 96 % and 98 %, respectively. After eight cycles, the biosorption and recovery efficiencies of TE-OP@C were higher than 90 %. Biocomposite was able to remove approximately 90 % and 88 % of Cu(II) from real wastewater in batch and continuous systems, respectively. FTIR analysis, zeta potential measurements, EDX, and SEM findings confirmed the Cu(II) uptake. XRD and BET analysis were also performed for biocomposite characterization. Breakthrough and exhausted points were determined as 80 and 150 min, respectively. The findings potentially lead to a new perspective on the treatment of copper contamination.


Asunto(s)
Quitosano , Olea , Contaminantes Químicos del Agua , Cobre/análisis , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
4.
J Environ Manage ; 298: 113548, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34426225

RESUMEN

One of the most important environmental and health issues today is the elimination of the dye pollution from the contaminated water ecosystem. The use of geopolymers to eliminate such contaminants has recently emerged as a promising alternative. In this study, metakaolin based geopolymer (MKBG) was synthesized to be a promising adsorbent for Basic Blue 7 (BB7). To optimize the input parameters (solution pH, MKBG dose, mixing time, temperature, mixing speed, column diameter, and flow rate) towards BB7 removal by MKBG, a Box-Behnken design (BBD) was employed to develop the response model, followed by numerical optimization. The quadratic models correlating the adsorption variables to BB7 adsorption yield as responses were developed for batch and dynamic flow systems. The pseudo-second-order model accurately predicted the BB7 adsorption kinetics on MKBG. Decolorization yields of BB7 in batch and continuous systems reached 96 % and 56 %, respectively. The Langmuir model accurately described equilibrium data, thereby justifying monolayer and homogeneous adsorption. The MKBG demonstrated significant reusability up to 20 dynamic flow adsorption cycles. IR, SEM, and zeta potential measurements were used to describe the sorbent structure, and the mechanism of MKBG-BB7 interaction was assessed. Overall, MKBG offers a good application potential for the treatment of basic dye contaminated waters.


Asunto(s)
Contaminantes Químicos del Agua , Adsorción , Ecosistema , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/análisis
5.
Carbohydr Polym ; 269: 118266, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34294298

RESUMEN

An effective and sustainable biosorbent (MagOPIC) was prepared from chitosan and olive pomace by the combined action of immobilization and magnetic modification to remediate Pb2+-contaminated waters. Pb2+ sorption yield at the end of the equilibrium (45 min) period was estimated to be 98.56 ±â€¯0.28% at pH 5.5. Agitation speed, ionic strength, and temperature did not significantly affect the Pb2+ biosorption. Biosorption kinetics are successfully fitted by the pseudo-second-order equation while the equilibrium biosorption data are properly modeled using the Freundlich and D-R isotherms. MagOPIC has also exhibited a high biosorption yield in the column tests (≥99%) and showed remarkable stability up to twenty consecutive regeneration cycles. Furthermore, it was successfully used for the treatment of Pb2+ containing real wastewater. The findings of this work highlighted the potential use of MagOPIC as a novel, cost-effective and eco-friendly biosorbent for the Pb2+ removal from the contaminated aquatic phase.

6.
J Environ Manage ; 289: 112490, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33819651

RESUMEN

The removal of toxic metals from the aquatic ecosystem is one of the most pressing environmental and public health concerns today. A strong potential has recently emerged for the removal of such metals using biochar sorbents. Biosorption technology could make a significant difference in the future. It is a viable and cost-effective alternative to the remediation of toxic pollutants utilizing various biomaterials. In the current study, batch and fixed-bed studies were performed to evaluate the performance of Capsicum annuum L. seeds biochar (CASB) as an alternative material in removing toxic Pb(II) from aqueous solutions. Removal characteristics were investigated by considering the equilibrium and kinetic aspects. Biosorption equilibrium was established within 40 min. The optimum dosage of CASB for Pb(II) removal was determined as 2.0 g L-1. Biosorption data were well predicted by a non-linear Langmuir isotherm model. Monolayer biosorption occurred for CASB with a maximum capacity of 36.43 mg g-1. Biosorption kinetics fitted well with a pseudo-first-order kinetic model. The external mass transfer may control Pb(II) transport mechanism. Dynamic flow mode biosorption and regeneration potential of CASB were also examined. The application of CASB exhibited a 100% removal yield in real apple juice samples spiked with low concentrations of Pb(II). Exhausted points for the CASB packed columns were recorded as 195 and 320 min for simulated wastewater (SW) and synthetic Pb(II) solution, respectively. FTIR, BET, SEM-EDX analysis, and zeta potential measurements were used for the characterization of biochar and assessment of the metal ion-biosorbent interaction mechanism. Finally, our study provides a practical approach for the uptake of Pb(II) ions from contaminated solutions.


Asunto(s)
Plomo , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico , Ecosistema , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/análisis
7.
Environ Sci Pollut Res Int ; 27(14): 16177-16188, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32112356

RESUMEN

A novel biomaterial was prepared by the immobilization of Phlebia gigantea cells in the medium containing lignocellulosic waste and used for the first time in the bioremediation purpose. The developed new biocomposite possesses higher Pb(II) retention potential when compared with the free microbial cells. It could remove Pb(II) up to 74.11% at a biosorbent dosage of 4.0 g L-1. Surface characterization was carried out through zeta potential, EDX, SEM, and IR studies to understand the metal-biocomposite interactions. The biosorption amount at equilibrium slightly decreased with the increase of the solution temperature. Kinetic data indicated Pb(II) biosorption onto suggested biocomposite fits well with the pseudo-first-order model. Biosorption equilibrium data suited Langmuir model with the highest coefficient of determination values. The immobilized material reached to maximum monolayer Pb(II) retention capacity (1.449 × 10-4 mol g-1) within the short equilibrium time (10 min). The designed biocomposite was also adapted to continuous flow mode sorption process. Regeneration tests by dynamic flow mode confirmed reutilization potential of biocomposite.


Asunto(s)
Plomo , Contaminantes Químicos del Agua/análisis , Adsorción , Biodegradación Ambiental , Biomasa , Concentración de Iones de Hidrógeno , Cinética , Termodinámica
8.
Environ Sci Pollut Res Int ; 26(25): 25834-25843, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31270772

RESUMEN

A new magnetic bio-based composite was designed by the magnetic modification of passively immobilized fungal cells. It was utilized for biosorptive decolorization of reactive dye-contaminated aquatic media. As a greener option, waste tea leaf tissues were used for the first time as an immobilization matrix for microbial cells. Immobilized magnetic cells (biomagsorbent) could be effectively used in both batch and dynamic flow mode treatment processes and real environmental application. Rapid equilibrium and high decolorization yields were observed for the target dye (reactive violet 1). The temperature did not significantly affect the process. Langmuir and the pseudo-second-order models could be better used to fit the process equilibrium and kinetics, respectively. Maximum monolayer sorption capacity was 152.88 mg g-1. High biosorption and desorption yields for 50 consecutive dynamic flow decolorization cycles were recorded as striking results. The breakthrough time was 3420 min. Simulated and industrial water treatment performance of biomagsorbent was found to be more than 90%. The mechanism was evaluated by IR and zeta potential analysis. The magnetic character of the sorbent provided good mechanical durability, easy separation, and excellent regeneration ability. Consequently, this work provides new insight into scalar enhancement of water treatment.


Asunto(s)
Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Biomasa , Cinética , Temperatura
9.
J Sci Food Agric ; 99(4): 1850-1861, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30264397

RESUMEN

BACKGROUND: Contamination of food, feed, beverages and even drinking water with biotoxins is a growing global concern because of their potential health risks. In this work, surface-modified sugar beet pulp waste was used for the biosorptive removal of zearalenone biotoxin from contaminated aquatic media. RESULTS: Infrared, Boehm titration, BET (Brunauer-Emmett-Teller) surface area and point of zero charge analysis were employed for surface characterization. Kinetic and equilibrium studies showed that biotoxin biosorption was well predicted by the pseudo-second-order kinetic model and the Langmuir isotherm model. Zearalenone was removed from the solution over a wide pH range (3.0-8.0) and within a short time (15 min). Maximum uptake capacity of modified biomass was recorded as 23.30 ± 0.17 g kg-1 . Highest removal yield in a dynamic flow mode (94.56 ± 0.13%) was achieved at 2 mL min-1 flow rate using 30 mg biosorbent. Regeneration experiments revealed high reusability potential of suggested biosorbent. Moreover, its application potential was tested in spiked samples of malt, beer and canned corn liquid. CONCLUSION: Detoxification potential of this renewable biomass was significantly enhanced after modification. Modified biomass could be used as an efficient and low-cost green-type material with good application potential for zearalenone detoxification. © 2018 Society of Chemical Industry.


Asunto(s)
Beta vulgaris/química , Residuos/análisis , Contaminantes Químicos del Agua/química , Zearalenona/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Temperatura , Contaminantes Químicos del Agua/aislamiento & purificación , Zearalenona/aislamiento & purificación
10.
Int J Phytoremediation ; 20(2): 145-152, 2018 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-28613136

RESUMEN

Biosorption is an effective alternative method for the control of water pollution caused by different pollutants such as synthetic dyes and metals. A new and efficient biomass system was developed from the passively immobilized fungal cells. The spongy tissue of Phragmites australis was considered as the carrier for the immobilization of Neurospora sitophila cells employed for the biosorption of Basic Blue 7. This plant tissue was used for the first time as a carrier for fungal cells. The biosorption was examined through batch- and continuous-mode operations. The biosorption process conformed well to the Langmuir model. Maximum monolayer biosorption capacity of the biosorbent was recorded as 154.756 mg g-1. Kinetic findings showed a very good compliance with the pseudo-second-order model. The negative values of ΔG° indicated a spontaneous nature of the biosorption process and a positive value of ΔH° (14.69 kJ mol-1) concluded favorable decolorization at high temperature. The scanning electron microscopy analysis showed that a porous, rippled, and rough surface of biomass system was covered with BB7 molecular cloud. IR results revealed that functional groups like -OH, -NH, and CË­O participated to the decolorization. Breakthrough and exhausted points were found as 360 and 570 minutes, respectively. The biomass system was successfully applied to the treatment of real wastewater.


Asunto(s)
Biodegradación Ambiental , Colorantes , Poaceae , Contaminantes Químicos del Agua , Purificación del Agua , Biomasa , Hongos , Cinética , Rosa Bengala/análogos & derivados
11.
J Environ Manage ; 204(Pt 1): 583-593, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28942189

RESUMEN

A novel biomass/polymer composite was fabricated by embedding Thamnidium elegans cells in acrylic network of p(3-Methoxyprophyl)acrylamide p(MPA) enriched with 2-Akrylamido-2-methyl-1-propane sulfonic acid (AMPS). Cd(II) retention potential of hydrogel (p(MPA-co-AMPS)) increased by 20.66% times after this enrichment. The gel matrix could be effectively entrapped the biomass and resulting sorbent applied to remove Cd(II) from water in batch and continuous modes. The main physico-chemical parameters are discussed in addition to characterization, regeneration and application studies of the suggested sorbent. Equilibrium occurred within 30 min and Langmuir model predicted the equilibrium data. Kinetics of Cd(II) removal onto immobilized biomass is modeled using the pseudo-second-order rate equation. Maximum monolayer sorption capacity was estimated to be 123.76 mg g-1 at 25 °C. Designed composite was successfully applied for the removal of Cd(II) from industrial wastewater. EDTA and HNO3 can be efficiently used for Cd(II) recovery and composite sorbent recycled for at least 12 cycles with nearly stable sorption performance.


Asunto(s)
Cadmio/química , Hongos/citología , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Biomasa , Concentración de Iones de Hidrógeno , Cinética , Agua
12.
Carbohydr Polym ; 143: 318-26, 2016 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-27083375

RESUMEN

This study was undertaken to prepare a novel and environmentally friendly composite for the use in the wastewater treatment process. This composite was produced by immobilizing alunite with a glucosamine biopolymer, chitosan. Batch and dynamic flow mode decolorization potential of the chitosan-alunite composite (CAC) was systematically evaluated in Acid Red 1 (AR1) and Reactive Red 2 (RR2) contaminated media. pH, sorbent dosage, contact time and flow rate were screened through the sorption experiments. Equilibrium sorption experiments indicated that CAC has very high sorption potential for RR2 and AR1 dyes with the maximum sorption capacities of 462.74 and 588.75 mg g(-1), respectively. Good regeneration and reuse potential in 20 consecutive cycles are other important advantages of this composite. More importantly, CAC could also be used in the treatment of real wastewater without performance decrease. Overall, this study suggests that CAC is a promising sorbent for the removal of anionic dyes from aqueous solutions.


Asunto(s)
Compuestos de Aluminio/química , Compuestos Azo/química , Quitosano/química , Colorantes/química , Naftalenosulfonatos/química , Compuestos de Potasio/química , Sulfatos/química , Triazinas/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Espectrofotometría Infrarroja , Temperatura , Aguas Residuales/análisis
13.
Environ Sci Pollut Res Int ; 21(22): 13055-68, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24996942

RESUMEN

A natural biosorbent obtained from Pyracantha coccinea was modified with an anionic surfactant to facilitate its dye removal ability. Modified biosorbent was successfully employed for the decolorization of Methyl Violet (MV)-contaminated solutions. A three-variable Box-Behnken design for response surface methodology was used to examine the function of independent operating variables. Optimum pH and biosorbent amount were found to be 6.0 and 0.055 g, respectively. The effects of temperature and ionic strength on the dye removal performance of biosorbent were also investigated. A biosorption equilibrium was attained within 30 min and experimental data fitted well to the pseudo-second-order model. The Langmuir isotherm model fitted adequately to the equilibrium data. The maximum monolayer biosorption capacity of the modified biosorbent was found to be 254.88 mg g(-1). Good biosorption yields were also recorded in continuous biosorption system. Ion exchange and complexation could be suggested as possible mechanisms for the biosorption. The developed modified biosorbent was regenerated up to 80.30 % by 0.005 M HCl. At real wastewater conditions, it has 86.23 ± 0.21 and 94.51 ± 1.09 % dye removal yields in batch and column systems, respectively. Modified biomaterial can be used as an effective biosorbent for the removal of MV dye from aqueous solution with high biosorption performance.


Asunto(s)
Violeta de Genciana/aislamiento & purificación , Preparaciones de Plantas/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Concentración de Iones de Hidrógeno , Análisis Multivariante , Concentración Osmolar , Pyracantha/química , Dodecil Sulfato de Sodio/química , Propiedades de Superficie , Tensoactivos/química , Temperatura
14.
Carbohydr Polym ; 94(1): 400-8, 2013 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23544555

RESUMEN

This study focused on the development of an efficient and practical biosorbent, a low cost and promising plant waste with cellulose-lignin polymeric structure, for the treatment of dye containing solutions. Thuja orientalis biomass was modified by citric acid and its biosorption potential was investigated with respect to pH (2.0-10.0), contact time (1-60 min), sorbent dosage (0.01-0.05 g), initial dye concentration (10-725 mg L(-1)) and flow rate (0.5-4.0 mL min(-1)). Modification significantly increased the biosorption of dye by 30% as compared with unmodified biomass. Kinetic data followed the pseudo-second-order model while the equilibrium data were well predicted by the Langmuir isotherm model. Maximum dye biosorption capacities for natural and modified biomasses were found to be 91.03 and 203.21 mg g(-1) at 30°C, respectively. Modified biosorbent exhibited very good regeneration potential up to 10 cycles and it was successfully used for the decolorization of synthetic solution in dynamic flow mode. Zeta potential measurements, IR, SEM and EDX analysis were used to characterize the possible dye-biosorbent interactions. Overall, the present study underlines the alternative use of modified T. orientalis cones for removal and recovery applications of cationic dye, Basic Blue 9.


Asunto(s)
Componentes Aéreos de las Plantas/química , Extractos Vegetales/química , Tiazinas/química , Thuja/química , Contaminantes Químicos del Agua/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Azul de Metileno , Microscopía Electrónica de Rastreo , Modelos Químicos , Concentración Osmolar , Polvos , Propiedades de Superficie , Temperatura , Purificación del Agua
15.
Colloids Surf B Biointerfaces ; 101: 307-14, 2013 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23010034

RESUMEN

This study focused on the improvement of the decolorization potential of biomass derived from Pyracantha coccinea. Alkyl benyzldimethyl ammonium chloride (ABDAC) was used as modification agent. Batch mode decolorization potential of modified biosorbent was explored at different operating conditions. ABDAC modification significantly increased the biosorption yield to 97.27%, which was 3.88 times higher than that of natural biomass. The prepared biosorbent was effectively used for the decolorization of Reactive Red 45 contaminated solutions after the optimization of biosorption conditions. The non-linear regression analysis was used to evaluate the isotherm and kinetic model parameters. Process followed the Langmuir isotherm model and the highest monolayer capacity of 152.49 mg g(-1) was obtained with a small amount of modified biosorbent. Kinetic studies indicated fast decolorization rate of the process following the pseudo-first-order model. Biosorption performance of the prepared biosorbent was tested in RR45 containing real wastewater sample. The possible dye biosorbent interactions in the biosorption process were explored by zeta potential, scanning electron microscobe and FTIR analysis.


Asunto(s)
Biomasa , Plantas/química , Compuestos de Amonio Cuaternario/química , Tensoactivos/química , Absorción , Algoritmos , Colorantes/química , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Pyracantha/química , Aguas del Alcantarillado/química , Soluciones , Temperatura , Termodinámica
16.
Bioresour Technol ; 101(19): 7271-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20471827

RESUMEN

Biosorption characteristics of a surfactant modified macro fungus were investigated for decolorization of Reactive Red 2 contaminated solutions. Better biosorption efficiency was obtained with a small amount of fungal biomass after modification process. Operating variables like pH, biomass amount, contact time, temperature, dye concentration, flow rate and column size were explored. The biosorption process followed the pseudo-second-order kinetic and Langmuir isotherm models. Thermodynamic data confirm that the biosorption process is spontaneous and endothermic in nature. Under optimized batch conditions, up to 141.53 mg dye g(-1) could be removed from solution in a relatively short time. Modification process was confirmed by FTIR spectroscopy and zeta potential studies. Possible dye-biosorbent interactions were discussed. Good dynamic flow biosorption potential was observed for the suggested biosorbent in simulated wastewater. Overall, batch and continuous mode data suggest that this environmentally friendly and efficient biosorbent may be useful for the removal of reactive dyes from aqueous media.


Asunto(s)
Agaricus/metabolismo , Biomasa , Restauración y Remediación Ambiental/métodos , Naftalenosulfonatos/aislamiento & purificación , Reología , Triazinas/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción/efectos de los fármacos , Agaricus/efectos de los fármacos , Agaricus/crecimiento & desarrollo , Biodegradación Ambiental/efectos de los fármacos , Color , Concentración de Iones de Hidrógeno/efectos de los fármacos , Cinética , Modelos Químicos , Naftalenosulfonatos/química , Reología/efectos de los fármacos , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier , Tensoactivos/farmacología , Temperatura , Factores de Tiempo , Triazinas/química , Contaminantes Químicos del Agua/química
17.
J Hazard Mater ; 171(1-3): 865-71, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19631464

RESUMEN

This study focuses on the possible use of macro-fungus Agaricus bisporus to remove Acid Red 44 dye from aqueous solutions. Batch equilibrium studies were carried out as a function of pH, biomass amount, contact time and temperature to determine the decolorization efficiency of biosorbent. The highest dye removal yield was achieved at pH 2.0. Equilibrium occurred within about 30 min. Biosorption data were successfully described by Langmuir isotherm model and the pseudo-second-order kinetic model. The maximum monolayer biosorption capacity of biosorbent material was found as 1.19 x 10(-4) mol g(-1). Thermodynamic parameters indicated that the biosorption of Acid Red 44 onto fungal biomass was spontaneous and endothermic in nature. Fourier transform infrared spectroscopy and scanning electron microscopy were used for the characterization of possible dye-biosorbent interaction and surface structure of biosorbent, respectively. Finally the proposed biosorbent was successfully used for the decolorization of Acid Red 44 in synthetic wastewater conditions.


Asunto(s)
Compuestos Azo/aislamiento & purificación , Biodegradación Ambiental , Colorantes/farmacología , Hongos/metabolismo , Naftalenos/aislamiento & purificación , Adsorción , Agaricus/metabolismo , Compuestos Azo/química , Biomasa , Colorantes/química , Concentración de Iones de Hidrógeno , Residuos Industriales , Cinética , Naftalenos/química , Sales (Química)/química , Temperatura , Termodinámica , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos
18.
J Hazard Mater ; 168(2-3): 1302-9, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19362415

RESUMEN

This work reports on the assessment of the dye methylene blue biosorption properties of Pyracantha coccinea berries under different experimental conditions. Equilibrium and kinetic studies were carried out to determine the biosorption capacity and rate constants. The highest biosorption yield was observed at about pH 6.0, while the biosorption capacity of the biomass decreased with decreasing initial pH values. Batch equilibrium data obtained at different temperatures (15, 25, 35 and 45 degrees C) were modeled by Freundlich, Langmuir and Dubinin-Radushkevich (D-R) isotherms. Langmuir isotherm model fitted the equilibrium data, at the all studied temperatures, better than the other isotherm models indicating monolayer dye biosorption process. The highest monolayer biosorption capacity was found to be 127.50mg/g dry biomass at 45 degrees C. Kinetic studies indicate that the biosorption process followed the pseudo-second-order model, rather than the pseudo-first-order model. DeltaG degrees , DeltaH degrees and DeltaS degrees parameters of biosorption show that the process is spontaneous and endothermic in nature. The biosorbent-dye interaction mechanisms were investigated using a combination of Fourier transform infrared spectroscopy and scanning electron microscopy. The biosorption procedure was applied to simulated wastewater including several pollutants. The results obtained indicated that the suggested inexpensive and readily available biomaterial has a good potential for the biosorptive removal of basic dye.


Asunto(s)
Biomasa , Colorantes/metabolismo , Pyracantha/metabolismo , Cationes , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica
19.
J Hazard Mater ; 166(2-3): 1217-25, 2009 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-19153007

RESUMEN

This research deals with the evaluation of highly available and cost effective waste biomass of olive pomace for the removal of reactive textile dye, RR198 from aqueous medium and a real effluent. The experiments were conducted to assess the effects of process variables such as initial pH, biosorbent dosage, contact time, temperature and ionic strength. The results showed that the highest dye biosorption capacity was found at pH 2 and the needed time to reach the biosorption equilibrium was 40 min with a biosorbent concentration of 3.0 g L(-1). The sorption kinetics of dye was best described by the pseudo-second-order kinetic model. The equilibrium biosorption data were analyzed by Langmuir, Freundlich and Dubinin-Radushkevich isotherm models and the results from the isotherm studies showed that the RR198 biosorption process occurred on a homogenous surface of the biosorbent. The waste biomass of olive oil industry displayed biosorption capacities ranging from 6.05 x 10(-5) to 1.08 x 10(-4)mol g(-1) at different temperatures. The negative values of Delta G degrees and the positive value of Delta H degrees suggest that the biosorption process for RR198 was spontaneous and endothermic. Dye-biosorbent interactions were examined by FTIR and SEM analysis. Finally, high biosorption yield of olive waste for the removal of RR198 dye from real wastewater makes it possible that the olive pomace could be applied widely in wastewater treatment as biosorbent taking into account that no pretreatment on the solid residue is carried out.


Asunto(s)
Colorantes/aislamiento & purificación , Residuos Industriales/prevención & control , Naftalenosulfonatos/aislamiento & purificación , Olea/química , Triazinas/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Biomasa , Concentración de Iones de Hidrógeno , Residuos Industriales/economía , Concentración Osmolar , Termodinámica , Purificación del Agua/métodos
20.
J Hazard Mater ; 163(2-3): 1134-41, 2009 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-18755542

RESUMEN

Batch and dynamic flow biosorption studies were carried out using the waste biomass entrapped in silica-gel matrix for the removal of nickel(II) ions from synthetic solutions and real wastewater. Batch biosorption conditions were examined with respect to initial pH, S/L ratio, contact time, and initial nickel ion concentration. Zeta potential measurements showed that immobilized biosorbent was negatively charged in the pH range of 3.0-8.0. The immobilized biomass was found to possess relatively high biosorption capacity (98.01 mg g(-1)), and biosorption equilibrium was established in a short time of operation (5 min). The equilibrium data were followed by Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models. Scanning electron microscope analysis was used to screen the changes on the surface structure of the waste biomass after immobilization and nickel(II) biosorption. Sorbent-sorbate interactions were confirmed by Fourier transform infrared spectroscopy. The applicability of sorbent system was investigated in a continuous mode, and column studies were performed under different flow rate, column size, and biosorbent dosage. Also, the proposed sorbent system was successfully used to remove the nickel ions from industrial wastewater in dynamic flow treatment mode. The results showed that silica-immobilized waste biomass was a low-cost promising sorbent for sequester of nickel(II) ions from synthetic and real wastewater.


Asunto(s)
Biodegradación Ambiental , Níquel/aislamiento & purificación , Biomasa , Residuos Industriales , Níquel/metabolismo , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos
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