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1.
Environ Res ; 258: 119430, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38885826

RESUMO

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.

2.
Environ Sci Pollut Res Int ; 31(17): 25836-25848, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38488918

RESUMO

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.


Assuntos
Fusarium , Poluentes Químicos da Água , Zea mays , Biodegradação Ambiental , Descontaminação , Inflorescência , Termodinâmica , Cinética , Adsorção , Concentração de Íons de Hidrogênio , Biomassa
3.
Int J Biol Macromol ; 221: 865-873, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36063895

RESUMO

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.


Assuntos
Quitosana , Olea , Poluentes Químicos da Água , Cobre/análise , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
4.
Nutr Cancer ; 74(1): 265-277, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33590797

RESUMO

Propolis is a candidate for cancer treatment with its activity against different tumor cells and, has a wide spectrum of biological and pharmacological activities due to the diversity of its components. In this study, antitumorigenic activities of ethanol extract of propolis (EEP) and ethanol extract of propolis loaded niosome (PLN) were compared using 2D and 3D cell culture. Niosome formulations were prepared by thin film hydration technique. Cell viability of EEP and PLN was analyzed on MCF7, A549, MDA-MB-231, SK-MEL, SK-BR-3, DU145 and L-929 cell lines using MTT assay. L929, MCF7 and A549 cells were cultured using the 3D petri dish technique and their spherical forms were obtained after 142 h. After 24 h, PLN and EEP application, cell viability analysis was performed on 3D cultures with WST assay. As a result, niosome formulations containing EEP showed higher activity than ethanol extract of propolis in cancer cells. While a slow decrease was observed in cell viability in EEP treated cancer cells, it was observed that the percentage viability rates decreased in a shorter time in PLN treated cancer cells. Also, PLN can be used as an anticancer activity drug such as Doxorubicin, but this is not the case for EEP.


Assuntos
Neoplasias , Própole , Linhagem Celular , Etanol , Lipossomos , Extratos Vegetais/farmacologia , Própole/farmacologia
5.
J Environ Manage ; 298: 113548, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34426225

RESUMO

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.


Assuntos
Poluentes Químicos da Água , Adsorção , Ecossistema , Concentração de Íons de Hidrogênio , Cinética , Poluentes Químicos da Água/análise
6.
Carbohydr Polym ; 269: 118266, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34294298

RESUMO

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.

7.
J Environ Manage ; 289: 112490, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33819651

RESUMO

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.


Assuntos
Chumbo , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Ecossistema , Concentração de Íons de Hidrogênio , Cinética , Poluentes Químicos da Água/análise
8.
Environ Sci Pollut Res Int ; 27(14): 16177-16188, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32112356

RESUMO

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.


Assuntos
Chumbo , Poluentes Químicos da Água/análise , Adsorção , Biodegradação Ambiental , Biomassa , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica
9.
Environ Sci Pollut Res Int ; 26(25): 25834-25843, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31270772

RESUMO

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.


Assuntos
Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Biomassa , Cinética , Temperatura
10.
Environ Sci Pollut Res Int ; 26(23): 23279-23291, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31197670

RESUMO

The use of alunite as an adsorbent for the removal of dye was the aim of this report. Mixing the alunite with different salts may allow adsorption with higher efficiency. In the present study, the thermal decomposition product of alunite-potassium chloride mixture (TDPA-KCl) was used efficiently and inexpensively to remove Reactive Blue 49 (RB49) dye. The adsorption capacity of TDPA-KCl was found to be affected by pH, temperature, adsorbent amount, calcination temperature, dye concentration, and ionic strength. The highest RB49 adsorption yield was obtained at an initial pH of 2 and an equilibrium was reached within 20 min using 80 mg of adsorbent. The most suitable kinetic model was found as the pseudo-second-order and compatible isotherm was determined as the Langmuir model. The optimum adsorption capacity was found as 119.10 mg g-1 at 40 °C. ∆G°, ∆H°, and ∆S° values were calculated. A positive value of ∆H° stated that the adsorption is exothermic and spontaneous. In addition, ∆G° showed a more negative value when temperature was increased. Column studies indicated that TDPA-KCl could be effectively used for five cycles without any loss in its desorption potential. Breakthrough studies also supported a favorable adsorption of RB49 onto TDPA-KCl. This study showed that TDPA-KCl is a practical, efficient, and inexpensive adsorbent to remove reactive dyes from wastewater.


Assuntos
Compostos de Alumínio/química , Corantes/análise , Cloreto de Potássio/química , Compostos de Potássio/química , Sulfatos/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Têxteis , Águas Residuárias/química
11.
Technol Health Care ; 27(S1): 59-66, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31045527

RESUMO

In 2005, global cardiovascular diseases caused 30% of deaths in Europe, which is 46% of total deaths for all death groups. Today, according to the International Adult Diabetes Federation, 20% to 25% of the adult population in the world has Metabolic Syndrome. Turkish Statistical Institute claims that in Turkey 408782 people died of circulatory system diseases in 2016 and it is expected that numbers will dramatically increase. In 2003, total worldwide healthcare budget of Diabetes Mellitus was up to 64.9 billion International Dollars with the continuing rise in prevalence, it is expected that total costs will increase to 396 billion International Dollars by 2025. The main purpose of this study was to present a clinical decision support system that calculates Metabolic Syndrome existence and evaluate HeartScore risk level for Turkish population. The second objective was to create a detailed personal report about individual's risk level of Metabolic Syndrome and HeartScore and give advice to him/her to reduce it. The fuzzy logic risk assessment system (FLRAS) was formed in LabVIEW graphical development platform according to International Diabetes Federation and European Heart Journal's criteria. Mamdani type fuzzy logic sets were identified for each input variable and membership functions were assigned depending on the magnitude of the input limits. System's performance was tested on 96 (72 females, 24 males) patient data. Results show that the proposed system was able to evaluate the Metabolic Syndrome risk with 0.9285 specificity, 0.92708 accuracy and 0.925 sensitivity.


Assuntos
Doenças Cardiovasculares , Sistemas de Apoio a Decisões Clínicas , Lógica Fuzzy , Síndrome Metabólica , Doenças Cardiovasculares/mortalidade , Sistemas de Apoio a Decisões Clínicas/estatística & dados numéricos , Feminino , Humanos , Masculino , Medição de Risco/métodos , Turquia/epidemiologia
12.
J Sci Food Agric ; 99(4): 1850-1861, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30264397

RESUMO

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.


Assuntos
Beta vulgaris/química , Resíduos/análise , Poluentes Químicos da Água/química , Zearalenona/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Poluentes Químicos da Água/isolamento & purificação , Zearalenona/isolamento & purificação
13.
Int J Phytoremediation ; 20(2): 145-152, 2018 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-28613136

RESUMO

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.


Assuntos
Biodegradação Ambiental , Corantes , Poaceae , Poluentes Químicos da Água , Purificação da Água , Biomassa , Fungos , Cinética , Rosa Bengala/análogos & derivados
14.
J Environ Manage ; 204(Pt 1): 583-593, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28942189

RESUMO

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.


Assuntos
Cádmio/química , Fungos/citologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Biomassa , Concentração de Íons de Hidrogênio , Cinética , Água
15.
Carbohydr Polym ; 143: 318-26, 2016 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-27083375

RESUMO

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.


Assuntos
Compostos de Alumínio/química , Compostos Azo/química , Quitosana/química , Corantes/química , Naftalenossulfonatos/química , Compostos de Potássio/química , Sulfatos/química , Triazinas/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Espectrofotometria Infravermelho , Temperatura , Águas Residuárias/análise
16.
Environ Sci Pollut Res Int ; 21(22): 13055-68, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24996942

RESUMO

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.


Assuntos
Violeta Genciana/isolamento & purificação , Preparações de Plantas/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Análise Multivariada , Concentração Osmolar , Pyracantha/química , Dodecilsulfato de Sódio/química , Propriedades de Superfície , Tensoativos/química , Temperatura
17.
Carbohydr Polym ; 94(1): 400-8, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23544555

RESUMO

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.


Assuntos
Componentes Aéreos da Planta/química , Extratos Vegetais/química , Tiazinas/química , Thuja/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno , Microscopia Eletrônica de Varredura , Modelos Químicos , Concentração Osmolar , Pós , Propriedades de Superfície , Temperatura , Purificação da Água
18.
Colloids Surf B Biointerfaces ; 101: 307-14, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23010034

RESUMO

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.


Assuntos
Biomassa , Plantas/química , Compostos de Amônio Quaternário/química , Tensoativos/química , Absorção , Algoritmos , Corantes/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Pyracantha/química , Esgotos/química , Soluções , Temperatura , Termodinâmica
19.
J Hazard Mater ; 227-228: 107-17, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22673058

RESUMO

The biosorption properties of APDC modified S. albus were tested in batch and column conditions. Effective experimental parameters such as pH, biosorbent dosage, contact time, temperature, initial lead(II) ion concentration, flow rate and bed height were investigated. The biosorption capacity of modified biosorbent was at maximum when lead(II) solution pH and biosorbent dosage were 5.5 and 2.0 g L(-1), respectively. The biosorption equilibrium was established in 20 min. Langmuir isotherm fitted well to the equilibrium data and kinetics is found to fit pseudo-second-order model. Increase in ionic strength of lead(II) solutions caused a slight decrease in the biosorption yield of APDC-modified biosorbent. Co-ions affected the biosorption performance of modified biomass up to maximum 20.81% reduction. Column biosorption of lead(II) showed higher biosorption yields at lower flow rates. Required time of breakthrough point was found to be 200 min. The recommended mechanism was found to depend mainly on electrostatic interaction, ion-exchange and complex formation. The ion-exchange mechanism for lead(II) biosorption onto the modified biosorbent is verified from the ionic strength effect and EDX analysis. Carbonyl, phosphate and CN groups on the modified surface of S. albus were found to responsible for complexation with lead(II).


Assuntos
Chumbo/química , Pirrolidinas/química , Symphoricarpos , Tiocarbamatos/química , Poluentes Químicos da Água/química , Adsorção , Biomassa , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Concentração Osmolar , Symphoricarpos/ultraestrutura , Temperatura , Fatores de Tempo , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
20.
J Hazard Mater ; 171(1-3): 865-71, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19631464

RESUMO

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.


Assuntos
Compostos Azo/isolamento & purificação , Biodegradação Ambiental , Corantes/farmacologia , Fungos/metabolismo , Naftalenos/isolamento & purificação , Adsorção , Agaricus/metabolismo , Compostos Azo/química , Biomassa , Corantes/química , Concentração de Íons de Hidrogênio , Resíduos Industriais , Cinética , Naftalenos/química , Sais/química , Temperatura , Termodinâmica , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos
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