151
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Zhou J, Tang C, Cheng B, Yu J, Jaroniec M. Rattle-type carbon-alumina core-shell spheres: synthesis and application for adsorption of organic dyes. ACS APPLIED MATERIALS & INTERFACES 2012; 4:2174-2179. [PMID: 22458371 DOI: 10.1021/am300176k] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Porous micro- and nanostructured materials with desired morphologies and tunable pore sizes are of great interests because of their potential applications in environmental remediation. In this study, novel rattle-type carbon-alumina core-shell spheres were prepared by using glucose and metal salt as precursors via a simple one-pot hydrothermal synthesis followed by calcination. The microstructure, morphology, and chemical composition of the resulting materials were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N(2) adsorption-desorption techniques. These rattle-type spheres are composed of a porous Al(2)O(3) shell (thickness ≈ 80 nm) and a solid carbon core (diameter ≈ 200 nm) with variable space between the core and shell. Furthermore, adsorption experiments indicate that the resulting carbon-alumina particles are powerful adsorbents for the removal of Orange-II dye from water with maximum adsorption capacity of ~210 mg/g. It is envisioned that these rattle-type composite particles with high surface area and large cavities are of particular interest for adsorption of pollutants, separation, and water purification.
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Affiliation(s)
- Jiabin Zhou
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing and School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, P R China
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152
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Fil BA, Boncukcuoğlu R, Yilmaz AE, Bayar S. Adsorption of Ni(II) on ion exchange resin: Kinetics, equilibrium and thermodynamic studies. KOREAN J CHEM ENG 2012. [DOI: 10.1007/s11814-012-0012-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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153
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Adsorption of [meso-tetrakis(4-sulfonatophenyl)porphyrinato]oxovanadate(IV)(4–) onto chitosan in aqueous solution. Polym Bull (Berl) 2012. [DOI: 10.1007/s00289-011-0696-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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154
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Wang X, Pan J, Guan W, Zou X, Huo P, Yan Y, Hu W. Selective recognition of sesamol using molecularly imprinted polymers containing magnetic wollastonite. J Sep Sci 2011; 34:3287-94. [DOI: 10.1002/jssc.201100358] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 08/22/2011] [Accepted: 08/22/2011] [Indexed: 11/05/2022]
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155
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Yang Y, Tian C, Zhao X. Adsorption kinetics of methylene blue onto Fe-doped sulfated titania. Colloids Surf A Physicochem Eng Asp 2011. [DOI: 10.1016/j.colsurfa.2011.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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156
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Kinetics and thermodynamic study of aniline adsorption by multi-walled carbon nanotubes from aqueous solution. J Colloid Interface Sci 2011; 360:760-7. [DOI: 10.1016/j.jcis.2011.04.097] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2011] [Revised: 04/21/2011] [Accepted: 04/26/2011] [Indexed: 11/20/2022]
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157
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Aydin F, Yasar F, Aydin I, Guzel F. Determination of lead separated selectively with ion exchange method from solution onto BCW in Sirnak, East Anatolia of Turkey. Microchem J 2011. [DOI: 10.1016/j.microc.2011.02.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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158
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Fan J, Cai W, Yu J. Adsorption of N719 Dye on Anatase TiO2 Nanoparticles and Nanosheets with Exposed (001) Facets: Equilibrium, Kinetic, and Thermodynamic Studies. Chem Asian J 2011; 6:2481-90. [DOI: 10.1002/asia.201100188] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Indexed: 11/10/2022]
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159
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Masitah H, Bassim H, Latif A, Zulfakar M, Naimah I, Salwa M. Low Cost Removal of Reactive Orange 16 Dye using Cross-linked Chitosan/oil Palm Ash Composite Beads. ACTA ACUST UNITED AC 2011. [DOI: 10.3923/jas.2011.2292.2298] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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160
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Caqueret V, Cagnon B, Bostyn S, Fauduet H. Removal of dark coloured and polyphenolic compounds of sugar beet vinasse by adsorption onto activated carbons: Application to a crosscurrent adsorption process. CAN J CHEM ENG 2011. [DOI: 10.1002/cjce.20550] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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161
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Zhang XL, Cai ZS, Zhao YP, Sun G. Adsorption kinetics and isotherms of a pesticide on polyester fibers by carrier finishing. J Appl Polym Sci 2011. [DOI: 10.1002/app.33103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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162
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Sun SS, Tang RC. Adsorption and UV Protection Properties of the Extract from Honeysuckle onto Wool. Ind Eng Chem Res 2011. [DOI: 10.1021/ie101505q] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sha-Sha Sun
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, 199 Renai Road, Suzhou 215123, P. R. China
| | - Ren-Cheng Tang
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, 199 Renai Road, Suzhou 215123, P. R. China
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163
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Ren R, Li K, Zhang C, Liu D, Sun J. Biosorption of tetradecyl benzyl dimethyl ammonium chloride on activated sludge: kinetic, thermodynamic and reaction mechanisms. BIORESOURCE TECHNOLOGY 2011; 102:3799-3804. [PMID: 21195609 DOI: 10.1016/j.biortech.2010.12.032] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 12/02/2010] [Accepted: 12/06/2010] [Indexed: 05/30/2023]
Abstract
The biosorption of tetradecyl benzyl dimethyl ammonium chloride (C(14)BDMA) onto activated sludge was examined in aqueous solution with respect to the contact time, temperature and particle size. Equilibrium reached in about 2h contact time. An decrease in the temperature increases of biosorption capacity of C(14)BDMA onto activated sludge, which also increases with decreasing particle size. The experimental data fit the pseudo-second-order kinetics model well. The Langmuir and Freundlich models were applied to describe equilibrium isotherms, and the equilibrium partitioning data was described well by both models. Thermodynamic data showed that C(14)BDMA biosorption onto activated sludge was feasible, spontaneous and exothermic. The Fourier transform infrared (FT-IR) spectrophotometry results show that both physisorption and chemisorption were involved. The measured zeta potential values and the enhanced cation concentration indicate the presence of electrostatic interactions, hydrophobic interactions and ion exchange.
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Affiliation(s)
- Rong Ren
- College of Environmental Science and Engineering/Tianjin Key Laboratory of Environmental Remediation and Pollution Control/Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Wei Jin Road 94, Tianjin 300071, China
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164
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Parmar K, Chongder D, Bandyopadhya NR, Bhattacharjee S. Investigation on Cu(II) adsorption on cobalt silicate precipitation tube (CSPT) in aqueous medium. JOURNAL OF HAZARDOUS MATERIALS 2011; 185:1326-1331. [PMID: 21071141 DOI: 10.1016/j.jhazmat.2010.10.049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 10/05/2010] [Accepted: 10/11/2010] [Indexed: 05/30/2023]
Abstract
Cu(II) adsorption on cobalt silicate precipitation tube (CSPT) in aqueous medium has been reported. These tubes are porous with negative surface sites having isoelectric point (IEP) at pH 4.4. Cu(II) adsorption data follow Langmuir isotherm. CSPT has high Cu(II) loading capacity, which is a function of both Cu(II) concentration and CSPT weight. Adsorption bond energy obtained from Langmuir isotherm suggests a physisorption process. The adsorption process is endothermic and spontaneous. Adsorption kinetics follows pseudo second order model with activation energy (15.4 kJ mol(-1)) typical for physisorption process.
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Affiliation(s)
- K Parmar
- National Metallurgical Laboratory, Council of Scientific and Industrial Research, Jamshedpur 831007, India
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165
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Shao D, Hu J, Jiang Z, Wang X. Removal of 4,4'-dichlorinated biphenyl from aqueous solution using methyl methacrylate grafted multiwalled carbon nanotubes. CHEMOSPHERE 2011; 82:751-758. [PMID: 21109285 DOI: 10.1016/j.chemosphere.2010.10.086] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Revised: 10/22/2010] [Accepted: 10/31/2010] [Indexed: 05/30/2023]
Abstract
Methyl methacrylate (MMA) is grafted on multiwalled carbon nanotubes (MWCNTs) by using N(2) plasma technique. The MMA grafted MWCNTs (MWCNT-g-pMMA) are characterized by using Raman spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, thermo gravimetric analysis-differential thermal analysis (TGA-DTA), and potentiometric acid-base titration method. The application of MWCNT-g-pMMA in the removal of 4,4'-dichlorinated biphenyl (4,4'-DCB) from large volumes of aqueous solutions is investigated under ambient conditions. The results indicate that the adsorption of 4,4'-DCB on MWCNT-g-pMMA is much higher than that of 4,4'-DCB on MWCNTs, and the adsorbed 4,4'-DCB is difficult to be thermally decomposed from MWCNT-g-pMMA according to the TGA-DTA analysis. MWCNT-g-pMMA are suitable materials in the preconcentration and immobilization of polychlorinated biphenyls (PCBs) from large volumes of aqueous solutions in environmental pollution cleanup.
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Affiliation(s)
- Dadong Shao
- Key Laboratory of Novel Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei 230031, PR China
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166
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Zhou J, Cheng Y, Yu J, Liu G. Hierarchically porous calcined lithium/aluminum layered double hydroxides: Facile synthesis and enhanced adsorption towards fluoride in water. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm13645c] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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167
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Na CK, Park HJ. Defluoridation from aqueous solution by lanthanum hydroxide. JOURNAL OF HAZARDOUS MATERIALS 2010; 183:512-520. [PMID: 20702038 DOI: 10.1016/j.jhazmat.2010.07.054] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 06/08/2010] [Accepted: 07/12/2010] [Indexed: 05/29/2023]
Abstract
This research was undertaken to evaluate the feasibility of lanthanum hydroxide for fluoride removal from aqueous solutions. A batch sorption experiments were conducted to study the influence of various factors such as pH, presence of competing anions, contact time, initial fluoride concentration and temperature on the sorption of fluoride on lanthanum hydroxide. The optimum fluoride removal was observed in the pH(eq)≤7.5. The presence of competing anions showed no adverse effect on fluoride removal. The equilibrium data reasonably fitted the Langmuir isotherm model, and the maximum monolayer sorption capacity was found to be 242.2 mg/g at pH(eq)≤7.5 and 24.8 mg/g at pH(eq)>10.0. The pseudo-second-order kinetic model described well the kinetic data, and resulted in the activation energy of 53.4-68.8 kJ/mol. It was suggested that the overall rate of fluoride sorption is likely to be controlled by the chemical process. Thermodynamic parameters such as ΔG°, ΔH° and ΔS° indicated that the nature of fluoride sorption is spontaneous and endothermic. The used lanthanum hydroxide could be regenerated by washing with NaOH solution. Results from this study demonstrate the potential usability of lanthanum hydroxide as a good fluoride selective sorbent.
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Affiliation(s)
- Choon-Ki Na
- Department of Environmental Engineering, Mokpo National University, 61 Dorim, Chungkye Muan, Jeonnam 534-729, South Korea.
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168
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Li Q, Chai L, Yang Z, Wang Q, Wang Y. A comparative study of Ag(I) adsorption on raw and modified spent grain: kinetic and thermodynamic aspects. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2010; 82:2290-2296. [PMID: 21141392 DOI: 10.2175/106143010x12681059116978] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The capability of modified spent grain (MSG) to adsorb silver (I) [Ag(I)] from aqueous solution was investigated and compared with raw spent grain (RSG) regarding their adsorption isotherms, kinetics, and thermodynamics. The monolayer adsorption capacity was 30.28 mg/g for RSG and 158.23 mg/g for MSG according to the Langmuir isotherm. The Ag(I) adsorption on MSG was approximately 4 times higher than that on RSG. The pseudo-second-order kinetic model provided the best description of Ag(I) adsorption on the two adsorbents. The calculated activation energy (Ea) implies that the adsorption of Ag(I) on RSG is a physical adsorption and on MSG is of a chemical nature. Thermodynamic results suggest that the adsorption of Ag(I) is an exothermic process for RSG and an endothermic process for MSG, whereas both adsorption processes are spontaneous in nature.
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Affiliation(s)
- Qingzhu Li
- School of Metallurgical Science and Engineering, Central South University, Changsha, PR China
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169
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Kinetics and equilibrium studies for the removal of cadmium ions from aqueous solutions using Duolite ES 467 resin. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.minpro.2010.08.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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170
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Ahmad T, Rafatullah M, Ghazali A, Sulaiman O, Hashim R, Ahmad A. Removal of pesticides from water and wastewater by different adsorbents: a review. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, ENVIRONMENTAL CARCINOGENESIS & ECOTOXICOLOGY REVIEWS 2010; 28:231-271. [PMID: 21069614 DOI: 10.1080/10590501.2010.525782] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this review article, the use of various low-cost adsorbents for the removal of pesticides from water and wastewater has been reviewed. Pesticides may appear as pollutants in water sources, having undesirable impacts to human health because of their toxicity, carcinogenicity, and mutagenicity or causing aesthetic problems such as taste and odors. These pesticides pollute the water stream and it can be removed very effectively using different low-cost adsorbents. It is evident from a literature survey of about 191 recently published papers that low-cost adsorbents have demonstrated outstanding removal capabilities for pesticides.
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Affiliation(s)
- Tanweer Ahmad
- School of Industrial Technology, Universiti Sains Malaysia, Malaysia
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171
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Jiang J, Ng FTT. Production of low sulfur diesel fuel via adsorption: an equilibrium and kinetic study on the adsorption of dibenzothiophene onto NaY zeolite. ADSORPTION 2010. [DOI: 10.1007/s10450-010-9259-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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172
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Erdem B, Özcan AS, Özcan A. Preparation of HDTMA-bentonite: Characterization studies and its adsorption behavior toward dibenzofuran. SURF INTERFACE ANAL 2010. [DOI: 10.1002/sia.3230] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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173
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Preparation of high strength ultrafine polyvinyl chloride fibrous membrane and its adsorption of cationic dye. JOURNAL OF POLYMER RESEARCH 2009. [DOI: 10.1007/s10965-009-9368-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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174
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González A, Navia R, Moreno N. Fly ashes from coal and petroleum coke combustion: current and innovative potential applications. WASTE MANAGEMENT & RESEARCH : THE JOURNAL OF THE INTERNATIONAL SOLID WASTES AND PUBLIC CLEANSING ASSOCIATION, ISWA 2009; 27:976-987. [PMID: 19423583 DOI: 10.1177/0734242x09103190] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Coal fly ashes (CFA) are generated in large amounts worldwide. Current combustion technologies allow the burning of fuels with high sulfur content such as petroleum coke, generating non-CFA, such as petroleum coke fly ash (PCFA), mainly from fluidized bed combustion processes. The disposal of CFA and PCFA fly ashes can have severe impacts in the environment such as a potential groundwater contamination by the leaching of heavy metals and/or particulate matter emissions; making it necessary to treat or reuse them. At present CFA are utilized in several applications fields such as cement and concrete production, agriculture and soil stabilization. However, their reuse is restricted by the quality parameters of the end-product or requirements defined by the production process. Therefore, secondary material markets can use a limited amount of CFA, which implies the necessity of new markets for the unused CFA. Some potential future utilization options reviewed herein are zeolite synthesis and valuable metals extraction. In comparison to CFA, PCFA are characterized by a high Ca content, suggesting a possible use as neutralizers of acid wastewaters from mining operations, opening a new potential application area for PCFA that could solve contamination problems in emergent and mining countries such as Chile. However, this potential application may be limited by PCFA heavy metals leaching, mainly V and Ni, which are present in PCFA in high concentrations.
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Affiliation(s)
- Aixa González
- Department of Chemical Engineering, University of La Frontera, Temuco, Chile
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175
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Doğan M, Abak H, Alkan M. Adsorption of methylene blue onto hazelnut shell: Kinetics, mechanism and activation parameters. JOURNAL OF HAZARDOUS MATERIALS 2009; 164:172-181. [PMID: 18809255 DOI: 10.1016/j.jhazmat.2008.07.155] [Citation(s) in RCA: 250] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 07/29/2008] [Accepted: 07/30/2008] [Indexed: 05/26/2023]
Abstract
The adsorption kinetics of methylene blue (MB) on the hazelnut shell with respect to the initial dye concentration, pH, ionic strength, particle size and temperature were investigated. The rate and the transport/kinetic processes of MB adsorption were described by applying the first-order Lagergren, the pseudo-second-order, mass transfer coefficient and the intraparticle diffusion models. Kinetic studies showed that the kinetic data were well described by the pseudo-second-order kinetic model. Significant increases in initial adsorption rate were observed with the increase in temperature followed by pH and initial MB concentration. The intraparticle diffusion was found to be the rate-limiting step in the adsorption process. Adsorption activation energy was calculated to be 45.6kJmol(-1). The values of activation parameters such as free energy (DeltaG(*)), enthalpy (DeltaH(*)) and entropy (DeltaS(*)) were also determined as 83.4kJmol(-1), 42.9kJmol(-1) and -133.5Jmol(-1)K(-1), respectively.
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Affiliation(s)
- Mehmet Doğan
- Balikesir University, Faculty of Science and Literature, Department of Chemistry, Cagis Campus, 10145 Balikesir, Turkey.
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176
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Equilibrium, kinetics and thermodynamic aspects of Promethazine hydrochloride sorption by iron rich smectite. Colloids Surf A Physicochem Eng Asp 2009. [DOI: 10.1016/j.colsurfa.2009.03.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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177
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Peng S, Lü L, Wang J, Han L, Chen T, Jiang S. Study on the adsorption kinetics of orthophosphate anions on layer double hydroxide. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s11631-009-0184-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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178
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Adsorption of phosphate from aqueous solutions onto modified wheat residue: characteristics, kinetic and column studies. Colloids Surf B Biointerfaces 2009; 70:46-52. [PMID: 19152781 DOI: 10.1016/j.colsurfb.2008.12.006] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Revised: 11/25/2008] [Accepted: 12/03/2008] [Indexed: 02/03/2023]
Abstract
Kinetic and column adsorption of phosphate from aqueous solution using modified wheat residue (MWS) as an adsorbent were studied in a batch reactor. The respective characteristic rate constants and activation energy were presented after linear and non-linear fitting. In addition, the effects of influent concentration of phosphate and flow rates on the column adsorption were also investigated. The results showed that the adsorption process could reach equilibrium in 10-15 min, and the pseudo-second-order equation generated the best agreement with experimental data for adsorption systems. The activation energy was 3.39 kJ mol(-1) indicating that the synthesis process was a physical adsorption. In the column tests, the increase of influent concentration and flow rate both decreased the breakthrough time, and the MWS-packed column exhibited excellent phosphate removal from aqueous solution. These results provide strong evidence of the potential of MWS for the technological applications of phosphate removal from aqueous solutions.
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179
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Bekçi Z, Seki Y, Cavas L. Removal of malachite green by using an invasive marine alga Caulerpa racemosa var. cylindracea. JOURNAL OF HAZARDOUS MATERIALS 2009; 161:1454-1460. [PMID: 18562093 DOI: 10.1016/j.jhazmat.2008.04.125] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2008] [Revised: 04/24/2008] [Accepted: 04/29/2008] [Indexed: 05/26/2023]
Abstract
The biosorption of a cationic dye, malachite green oxalate (MG) from aqueous solution onto an invasive marine alga Caulerpa racemosa var. cylindracea (CRC) was investigated at different temperatures (298, 308 and 318 K). The dye adsorption onto CRC was confirmed by FTIR analysis. Equilibrium data were analyzed using Freundlich, Langmuir and Dubinin-Radushkevich (DR) equations. All of the isotherm parameters were calculated. The Freundlich model gave a better conformity than Langmuir equation. The mean free energy values (E) from DR isotherm were also estimated. In order to clarify the sorption kinetic, the fit of pseudo-first-order kinetic model, second-order kinetic model and intraparticle diffusion model were investigated. It was obtained that the biosorption process followed the pseudo-second-order rate kinetics. From thermodynamic studies the free energy changes were found to be -7.078, -9.848 and -10.864 kJ mol(-1) for 298, 308 and 318 K, respectively. This implied the spontaneous nature of biosorption and the type of adsorption as physisorption. Activation energy value for MG sorption (E(a)) was found to be 37.14 kJ mol(-1). It could be also derived that this result supported physisorption as a type of adsorption.
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Affiliation(s)
- Zehra Bekçi
- Dokuz Eylül University, Faculty of Arts and Sciences, Department of Chemistry, Division of Physical Chemistry, 35160 Kaynaklar Campus, Izmir, Turkey
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180
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Peng S, Ma M, Jin S, Chen T. Kinetics of p-nitrophenol adsorption by layered double oxides during its hydration. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2009; 81:91-96. [PMID: 19280904 DOI: 10.2175/106143008x274158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Kinetics of p-nitrophenol (PNP) adsorption onto layered double oxides (LDO) during its hydration into layered double hydroxides (LDH) was studied. Results indicate that the adsorption of PNP onto LDO is a spontaneous endothermic process. The adsorption isotherms correlate well with the Freundlich type model. Results suggest that the adsorption of PNP onto LDO is an entropy-increasing process, and it appears to be in agreement with pseudo-second-order kinetics. Intra-particle diffusion was found to take part in the adsorption processes, and it might be the primary rate-limiting step for the sorbing capacity of LDO to PNP. Results from X-ray diffraction and Fourier transform infrared indicate that PNP molecules are probably taken into the interlayer of the structure during the hydration of LDO into the LDH. Activated carbon was used as a benchmark material in evaluating the sorbing capacity of LDO to PNP. The sorbing capacity of LDO to PNP (32 mg PNP/g LDO) was well below activated carbon (659 mg PNP/g carbon); however, the sorbing process of LDO to PNP is also a unique synthetic process for LDH, which has been used in removing specific anionic species, such as bioagents and pharmaceutical intermediates from waters.
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Affiliation(s)
- Shuchuan Peng
- School of Resources and Environment, Hefei University of Technology, Hefei, PR China
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181
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Chakravarty S, Pimple S, Chaturvedi HT, Singh S, Gupta KK. Removal of copper from aqueous solution using newspaper pulp as an adsorbent. JOURNAL OF HAZARDOUS MATERIALS 2008; 159:396-403. [PMID: 18359157 DOI: 10.1016/j.jhazmat.2008.02.030] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2007] [Revised: 02/13/2008] [Accepted: 02/13/2008] [Indexed: 05/26/2023]
Abstract
Newspaper pulp was found to be a potential adsorbent for removal of copper from aqueous medium. Detail adsorption study of Cu on newspaper pulp was investigated. Batch adsorption study was carried out as a function of contact time, adsorbent dose, temperature (303-323 K). The experimental data was analyzed using Freundlich, Langmuir, Dubinin-Radushkevich (D-R) and Redlich-Peterson (R-P) isotherm models. It was found that Freundlich, Langmuir and R-P models fitted well. pH variation study revealed that the adsorption increased with increase in pH of the solution. Maximum loading capacity was found to be 30 mg g(-1) at 20 mg L(-1) of initial Cu concentration. Adsorption data were analyzed using two kinetic models, Lagergren first order and pseudo second order. It was observed that pseudo second order represented the best correlation. Langmuir isotherm was used to obtain the thermodynamic parameters such as free energy (DeltaG degrees ), enthalpy (DeltaH degrees ) and entropy (DeltaS degrees ) of adsorption. The negative value of free energy and positive value of enthalpy change indicate that the adsorption of Cu on newspaper pulp is a spontaneous process and endothermic. The results of activation energy also confirmed that the adsorption of Cu on newspaper pulp is physical in nature. Present investigation emphasized that newspaper pulp may be utilized as a low cost adsorbent for copper removal.
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Affiliation(s)
- S Chakravarty
- Analytical Chemistry Centre, National Metallurgical Laboratory, Jamshedpur 831007, India.
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182
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Calderón M, Moraga C, Leal J, Agouborde L, Navia R, Vidal G. The use of Magallanic peat as non-conventional sorbent for EDTA removal from wastewater. BIORESOURCE TECHNOLOGY 2008; 99:8130-8136. [PMID: 18468887 DOI: 10.1016/j.biortech.2008.03.064] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Revised: 03/14/2008] [Accepted: 03/14/2008] [Indexed: 05/26/2023]
Abstract
Kraft mills are responsible for large volumes discharges of highly polluted effluents. Application of new bleaching processes (i.e. total chlorine-free (TCF) process) is already a feasible option to reduce environmental impacts. The current trend in the increase in the production of TCF pulp will proportionally increase the consumption of chelating agents. The most commonly used chelants, ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DPTA) are supposed to be relatively persistent substances, poorly degradable in biological treatment facilities and are subsequently considered as environmentally critical compounds. Adsorption could be used as a treatment technique to remove recalcitrant compounds from wastewaters. However, in most cases, sorbent and regeneration costs can make the whole process not economically feasible. The goal of this study was to evaluate the use of Magallanic peat as non-conventional sorbent for EDTA removal from wastewater. Adsorption studies were carried out considering a 2(3) factorial design. pH, temperature and sorbent/sorbate (S/S) relationship effects were evaluated in EDTA adsorption onto Magallanic peat. In addition, adsorption isotherm constants were determined according to the Langmuir and Freundlich models. The results showed that the optimal conditions for EDTA adsorption onto Magallanic peat were 20 degrees C, acid pH (4.0) and a low sorbent/sorbate ratio (0.1/100). At these conditions Magallanic peat showed an adsorption capacity for EDTA (Cs(sat)) of 128.2mg/g, comparable and even better than activated carbon (Cs(sat) 56.5mg/g). EDTA adsorption data at 60 degrees C obtained are not shown due to Magallanic peat degradation phenomena.
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Affiliation(s)
- M Calderón
- Environmental Science Centre EULA-Chile, University of Concepción, P.O. Box 160-C, Concepción, Chile
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183
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Kuo CY, Wu CH, Wu JY. Adsorption of direct dyes from aqueous solutions by carbon nanotubes: Determination of equilibrium, kinetics and thermodynamics parameters. J Colloid Interface Sci 2008; 327:308-15. [DOI: 10.1016/j.jcis.2008.08.038] [Citation(s) in RCA: 237] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 08/19/2008] [Accepted: 08/20/2008] [Indexed: 10/21/2022]
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184
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Mashitah MD, Yus Azila Y, Bhatia S. Biosorption of cadmium (II) ions by immobilized cells of Pycnoporus sanguineus from aqueous solution. BIORESOURCE TECHNOLOGY 2008; 99:4742-4748. [PMID: 17981460 DOI: 10.1016/j.biortech.2007.09.062] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Revised: 09/21/2007] [Accepted: 09/22/2007] [Indexed: 05/25/2023]
Abstract
Biosorption of cadmium (II) ions from aqueous solution onto immobilized cells of Pycnoporus sanguineus (P. sanguineus) was investigated in a batch system. Equilibrium and kinetic studies were conducted by considering the effect of pH, initial cadmium (II) concentration, biomass loading and temperature. Results showed that the uptake of cadmium (II) ions increased with the increase of initial cadmium (II) concentration, pH and temperature. Langmuir, Freundlich and Redlich-Peterson isotherm models were used to analyze the equilibrium data at different temperatures. Langmuir isotherm model described the experimental data well followed by Redlich-Peterson and Freundlich isotherm models. Biosorption kinetics data were fitted using pseudo-first, pseudo-second-order and intraparticle diffusion. It was found that the kinetics data fitted well the pseudo-second-order followed by intraparticle diffusion. Thermodynamic parameters such as standard Gibbs free energy (Delta G0), standard enthalpy (Delta H0) and standard entropy (Delta S0) were evaluated. The result showed that biosorption of cadmium (II) ions onto immobilized cells of P. sanguineus was spontaneous and endothermic nature.
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Affiliation(s)
- M D Mashitah
- School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Seberang Prai Selatan, Pulau Pinang, Malaysia.
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185
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Xu K, Harper WF, Zhao D. 17alpha-Ethinylestradiol sorption to activated sludge biomass: thermodynamic properties and reaction mechanisms. WATER RESEARCH 2008; 42:3146-3152. [PMID: 18405936 DOI: 10.1016/j.watres.2008.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 03/06/2008] [Accepted: 03/07/2008] [Indexed: 05/26/2023]
Abstract
Sorption is an important mechanism for removal of 17alpha-ethinylestradiol (EE(2)) in biological wastewater treatment. In an effort to deepen our understanding of this process, this work investigated the underlying thermodynamic parameters. Biomass was harvested from a membrane bioreactor (MBR) and a sequencing batch reactor (SBR), and sorption experiments were conducted over a range of temperatures. Sorption of EE(2) to activated sludge was spontaneous (DeltaG values were between -16 and -11 KJ/mol), enthalpy-driven (DeltaH values were -37 KJ/mol (MBR) and -48 KJ/mol (SBR)), and entropy-retarded (DeltaS values were -74 (MBR) and -119 J/mol/K (SBR)). Although EE(2) is nonpolar, hydrophobic interactions were not dominant driving forces. The thermodynamic data also suggested that EE(2) sorption to biomass was primarily physisorption, but it also included low-level chemisorption. The FT-IR results suggested that chemical reactions were not significant enough to shift the detectable chemical bonding characteristics of the biomass functional groups.
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Affiliation(s)
- Kai Xu
- Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA
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186
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Ashour I, Abu Al-Rub FA, Sheikha D, Volesky B. Biosorption of Naphthalene from Refinery Simulated Waste-Water on Blank Alginate Beads and Immobilized Dead Algal Cells. SEP SCI TECHNOL 2008. [DOI: 10.1080/01496390801887351] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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187
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Lin JX, Zhan SL, Fang MH, Qian XQ, Yang H. Adsorption of basic dye from aqueous solution onto fly ash. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2008; 87:193-200. [PMID: 17307284 DOI: 10.1016/j.jenvman.2007.01.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2006] [Revised: 12/17/2006] [Accepted: 01/10/2007] [Indexed: 05/14/2023]
Abstract
The fly ash treated by H2SO4 was used as a low-cost adsorbent for the removal of a typical dye, methylene blue, from aqueous solution. An increase in the specific surface area and dye-adsorption capacity was observed after the acid treatment. The adsorption isotherm and kinetics of the treated fly ash were studied. The experimental results were fitted using Langmuir and Freundlich isotherms. It shows that the Freundlich isotherm is better in describing the adsorption process. Two kinetic models, pseudo-first order and pseudo-second order, were employed to analyze the kinetic data. It was found that the pseudo-second-order model is the better choice to describe the adsorption behavior. The thermodynamic study reveals that the enthalpy (delta H0) value is positive (5.63 kJ/mol), suggesting an endothermic nature of the adsorption.
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Affiliation(s)
- J X Lin
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310027, PR China; College of Materials and Chemical Engineering, Zhejiang University, Hangzhou 310027, PR China
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188
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189
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Studies on an economically viable remediation of chromium rich waters and wastewaters by PTPS fly ash. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2007.10.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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190
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Fu L, Wang J, Lu H, Su Y, Ren A. Comment on "the removal of phenolic compounds from aqueous solutions by organophilic bentonite". JOURNAL OF HAZARDOUS MATERIALS 2008; 151:851-854. [PMID: 18248887 DOI: 10.1016/j.jhazmat.2007.11.090] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2007] [Revised: 10/18/2007] [Accepted: 11/26/2007] [Indexed: 05/25/2023]
Abstract
Quotation and calculation accuracy can play a key role in a scientific paper. This comment mainly presents the possible errors in an article by Akçay et al., including the questionable expression of Polanyi potential (epsilon) in the Dubinin-Radushkevich (DR) equation used by the authors and the discrepancies in adsorption thermodynamic parameters study.
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Affiliation(s)
- Lin Fu
- College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
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191
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Argun ME. Use of clinoptilolite for the removal of nickel ions from water: kinetics and thermodynamics. JOURNAL OF HAZARDOUS MATERIALS 2008; 150:587-95. [PMID: 17561344 DOI: 10.1016/j.jhazmat.2007.05.008] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2007] [Revised: 05/03/2007] [Accepted: 05/04/2007] [Indexed: 05/15/2023]
Abstract
This paper describes the removal of Ni(II) ions from aqueous solutions using clinoptilolite. The effect of clinoptilolite level, contact time, and pH were determined. Different isotherms were also obtained using concentrations of Ni(II) ions ranging from 0.1 to 100 mg L(-1). The ion-exchange process follows second-order reaction kinetics and follows the Langmuir isotherm. The paper discusses thermodynamic parameters, including changes in Gibbs free energy, entropy, and enthalpy, for the ion-exchange of Ni(II) on clinoptilolite, and revealed that the ion-exchange process was spontaneous and exothermic under natural conditions. The maximum removal efficiency obtained was 93.6% at pH 7 and with a 45 min contact time (for 25 mg L(-1) initial concentration and a 15 g L(-1) solid-to-liquid ratio).
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Affiliation(s)
- Mehmet Emin Argun
- Department of Environmental Engineering, Engineering & Architecture Faculty, Selçuk University, 42003 Selçuklu-Konya, Turkey.
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192
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Hernandez-Ramirez O, Holmes SM. Novel and modified materials for wastewater treatment applications. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b716941h] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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193
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Adsorption of Maillard reaction products from aqueous solutions and sugar syrups using adsorbent resin. J FOOD ENG 2007. [DOI: 10.1016/j.jfoodeng.2007.02.048] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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194
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Nouri L, Ghodbane I, Hamdaoui O, Chiha M. Batch sorption dynamics and equilibrium for the removal of cadmium ions from aqueous phase using wheat bran. JOURNAL OF HAZARDOUS MATERIALS 2007; 149:115-25. [PMID: 17459582 DOI: 10.1016/j.jhazmat.2007.03.055] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Revised: 03/11/2007] [Accepted: 03/21/2007] [Indexed: 05/12/2023]
Abstract
Studies on a batch sorption process using wheat bran as a low cost sorbent was investigated to remove cadmium ions from aqueous solution. The influence of operational conditions such as contact time, cadmium initial concentration, sorbent mass, temperature, solution initial pH, agitation speed and ionic strength on the sorption kinetics of cadmium was studied. Pseudo-second-order model was evaluated using the six linear forms as well as the non-linear curve fitting analysis method. Modeling of kinetic results shows that sorption process is best described by the pseudo-second-order model using the non-linear method. The sorption of cadmium was found to be dependent on initial concentration, sorbent mass, solution pH, agitation speed, temperature, ionic strength and contact time. The value of activation energy (12.38 kJ mol(-1)) indicates that sorption has a low potential barrier corresponding to a physical process. Sorption equilibrium isotherms at different temperatures was determined and correlated with common isotherm equations such as Langmuir and Freundlich models. It was found that the Langmuir model appears to well fit the isotherm data but a worse correlation was obtained by the Freundlich model. The five Langmuir linear equations as well as the non-linear curve fitting analysis method were discussed. Results show that the non-linear method may be a better way to obtain the Langmuir parameters. Thermodynamic parameters such as DeltaH degrees, DeltaS degrees and DeltaG degrees were calculated. These parameters indicate that the sorption of cadmium by wheat bran is a spontaneous process and physical in nature involving weak forces of attraction and is also endothermic.
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Affiliation(s)
- Loubna Nouri
- Department of Process Engineering, Faculty of Engineering, University of Annaba, PO Box 12, 23000 Annaba, Algeria
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195
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Nouri L, Hamdaoui O. Ultrasonication-Assisted Sorption of Cadmium from Aqueous Phase by Wheat Bran. J Phys Chem A 2007; 111:8456-63. [PMID: 17676717 DOI: 10.1021/jp0721393] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the present study, the sorption of cadmium from aqueous phase by wheat bran was investigated with and without the assistance of ultrasound. Kinetic data and sorption equilibrium isotherms were carried out in batch conditions. The influence of different operating parameters such as ultrasonic power, cadmium initial concentration, sorbent mass, temperature, and the combination of ultrasound and mechanical stirring on the kinetics of cadmium removal was studied. The obtained results show that the ultrasonic irradiation significantly enhances and improves the efficiency of the removal of cadmium, especially in the combined method. The sorption kinetic data were found to be well-represented by the pseudo-second-order rate equation, both in the absence and presence of ultrasound as well as in the combined process (stirring and ultrasonication). Ultrasonic power played a key role in the removal of cadmium. Equilibrium isotherm results could be well described by the Langmuir model both with and without the assistance of ultrasound. The effect of temperature on the sorption isotherms of cadmium in the absence and presence of ultrasound has been also studied and the thermodynamic parameters DeltaG degrees, DeltaH degrees, and DeltaS degrees were determined. The monolayer sorption capacities were 51.81, 35.09, and 22.78 mg g(-1) for experiments conducted by the combined process, in the presence of ultrasound, and in passive conditions, respectively. The combination ultrasound-stirring for the sorption process was shown to be of interest for the treatment of wastewaters contaminated with cadmium.
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Affiliation(s)
- Loubna Nouri
- Department of Process Engineering, Faculty of Engineering, University of Annaba, P.O. Box 12, 23000 Annaba, Algeria
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196
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Onal Y, Akmil-Başar C, Sarici-Ozdemir C. Investigation kinetics mechanisms of adsorption malachite green onto activated carbon. JOURNAL OF HAZARDOUS MATERIALS 2007; 146:194-203. [PMID: 17194532 DOI: 10.1016/j.jhazmat.2006.12.006] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2006] [Revised: 12/04/2006] [Accepted: 12/04/2006] [Indexed: 05/12/2023]
Abstract
Lignite was used to prepare activated carbon (T3K618) by chemical activation with KOH. Pore properties of the activated carbon such as BET surface area, pore volume, pore size distribution, and pore diameter were characterized by t-plot based on N2 adsorption isotherm. BET surface area of activated carbon is determined as 1000 m2/g. Adsorption capacity of malachite green (MG) onto T3K618 activated carbon was investigated in a batch system by considering the effects of various parameters like initial concentration (100, 150 and 200 mg/L) and temperature (25, 40 and 50 degrees C). The adsorption process was relatively fast and equilibrium was reached after about 20 min for 100, 150 mg/L at all adsorption temperature. Equilibrium time for 200 mg/L was determined as 20 min and 40 min at 298, 313 and 323 K, respectively. Simple mass and kinetic models were applied to the experimental data to examine the mechanisms of adsorption and potential rate controlling steps such as external mass transfer, intraparticle diffusion. Pseudo second-order model was found to explain the kinetics of MG adsorption most effectively. It was found that both mass transfer and pore diffusion are important in determining the adsorption rates. The intraparticle diffusion rate constant, external mass transfer coefficient, film and pore diffusion coefficient at various temperatures were evaluated. The activation energy (Ea) was determined as 48.56, 63.16, 67.93 kJ/mol for 100, 150, 200 mg/L, respectively. The Langmiur and Freundlich isotherm were used to describe the adsorption equilibrium studies at different temperatures. Langmiur isotherm shows better fit than Freundlich isotherm in the temperature range studied. The thermodynamic parameters, such as DeltaG degrees, DeltaS and DeltaH degrees were calculated. The thermodynamics of dyes-T3K618 system indicates endothermic process.
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Affiliation(s)
- Y Onal
- Inonu University, Faculty of Engineering, Department of Chemical Engineering, 44280 Malatya, Turkey.
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197
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Wu CH. Studies of the equilibrium and thermodynamics of the adsorption of Cu2+ onto as-produced and modified carbon nanotubes. J Colloid Interface Sci 2007; 311:338-46. [PMID: 17442333 DOI: 10.1016/j.jcis.2007.02.077] [Citation(s) in RCA: 172] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Revised: 02/07/2007] [Accepted: 02/24/2007] [Indexed: 11/22/2022]
Abstract
This study evaluates the Cu(2+) adsorption efficiency of as-produced carbon nanotubes (CNTs) and those modified by HNO(3) and NaOCl. The surface area, pH(pzc), pore volume, FTIR analyses, and average pore size of CNTs were determined to compare the differences between nanotubes before and after HNO(3) and NaOCl modification. The HNO(3) and NaOCl modifications increased the pore volume and the average pore size of CNTs; in contrast, the pH(pzc) was decreased. The modification processes produced some functional groups. The adsorption capacity of Cu(2+) on as-produced and modified CNTs increased with the pH and temperature; however, the effects of the ionic strength on the adsorption of Cu(2+) on as-produced and modified CNTs were negligible. The linear correlation coefficients of Langmuir and Freundlich isotherms were obtained and the results revealed that the Langmuir isotherm fitted the experimental results better than did the Freundlich isotherm. The adsorption capacity of Cu(2+) followed the order NaOCl-modified CNTs > HNO(3)-modified CNTs > as-produced CNTs. Changes in the free energy of adsorption (DeltaG(o)), enthalpy (DeltaH(o)), and entropy (DeltaS(o)) were determined. All DeltaG(o) values were negative; the DeltaH(o) values of as-produced, HNO(3)-modified, and NaOCl-modified CNTs were 10.84, 17.08, and 67.77 kJ/mol and the DeltaS(o) values were 96.89, 122.88, and 319.76 J/mol K, respectively.
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Affiliation(s)
- Chung-Hsin Wu
- Department of Environmental Engineering, Da-Yeh University, 112 Shan-Jiau Road, Da-Tsuen, Chang-Hua, Taiwan.
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198
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Wu CH. Adsorption of reactive dye onto carbon nanotubes: equilibrium, kinetics and thermodynamics. JOURNAL OF HAZARDOUS MATERIALS 2007; 144:93-100. [PMID: 17081687 DOI: 10.1016/j.jhazmat.2006.09.083] [Citation(s) in RCA: 176] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Revised: 09/25/2006] [Accepted: 09/28/2006] [Indexed: 05/12/2023]
Abstract
The adsorption efficiency of carbon nanotubes for Procion Red MX-5B at various pHs and temperatures was examined. The amount adsorbed increased with the CNTs dosage; however, the adsorption capacity initially increased with the CNTs dosage (<0.25 g/l) and then declined as the CNTs dosage increased further (>0.25 g/l). The linear correlation coefficients and standard deviations of Langmuir and Freundlich isotherms were determined and the results revealed that Langmuir isotherm fitted the experimental results well. Kinetic analyses were conducted using pseudo first- and second-order models and the intraparticle diffusion model. The regression results showed that the adsorption kinetics were more accurately represented by a pseudo second-order model. Changes in the free energy of adsorption (DeltaG degrees ), enthalpy (DeltaH degrees ) and entropy (DeltaS degrees), as well as the activation energy (E(a)) were determined. DeltaH degrees and DeltaS degrees were 31.55 kJ/mol and 216.99J/molK, respectively, at pH 6.5 and 41.47 kJ/mol and 244.64 J/molK at pH 10. The activation energy was 33.35 kJ/mol at pH 6.5. DeltaH degrees, DeltaG degrees and E(a) all suggested that the adsorption of Procion Red MX-5B onto CNTs was by physisorption.
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Affiliation(s)
- Chung-Hsin Wu
- Department of Environmental Engineering, Da-Yeh University, 112 Shan-Jiau Road, Da-Tsuen, Chang-Hua, Taiwan, ROC.
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199
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Estevinho BN, Martins I, Ratola N, Alves A, Santos L. Removal of 2,4-dichlorophenol and pentachlorophenol from waters by sorption using coal fly ash from a Portuguese thermal power plant. JOURNAL OF HAZARDOUS MATERIALS 2007; 143:535-40. [PMID: 17141954 DOI: 10.1016/j.jhazmat.2006.09.072] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2006] [Revised: 09/11/2006] [Accepted: 09/25/2006] [Indexed: 05/12/2023]
Abstract
Chlorophenols are one of the most important groups of priority pollutants, due to their high toxicity, mutagenicity and carcinogenicity. Although activated carbon has been the preferred choice for the removal of such pollutants from wastewaters, the search for cheaper alternative sorbents became common in the last years. Fly ash, a by-product from coal burning power plants, has a surface composition that may enable the sorption of specific organic compounds. Therefore, this feasibility study presents the optimization of the operating parameters of a fixed-bed column containing fly ash particles, percolated by aqueous solutions of 2,4-dichlorophenol (2,4-DCP) and pentachlorophenol (PCP) with concentrations of 1 and 100 microg/ml. Both chlorophenols were analysed by gas chromatography with electron capture detection (GC-ECD), after solid-phase microextraction (SPME), with limits of detection (LODs) of 7.28 microg/l for 2,4-DCP and 1.76 microg/l for PCP. Removal efficiencies above 99% were obtained for an initial concentration of 10 microg/ml of chlorophenols. Column saturation was achieved after 7h of continuous operation for 2,4-DCP and 10h for the PCP for feed levels of 10 microg/ml. Fly ash exhibited more affinity towards the sorption of PCP, in comparison to 2,4-DCP.
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Affiliation(s)
- Berta N Estevinho
- LEPAE, Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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200
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Li Y, Liu C, Luan Z, Peng X, Zhu C, Chen Z, Zhang Z, Fan J, Jia Z. Phosphate removal from aqueous solutions using raw and activated red mud and fly ash. JOURNAL OF HAZARDOUS MATERIALS 2006; 137:374-83. [PMID: 16621271 DOI: 10.1016/j.jhazmat.2006.02.011] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2005] [Revised: 11/23/2005] [Accepted: 02/13/2006] [Indexed: 05/08/2023]
Abstract
The effect of acidification and heat treatment of raw red mud (RM) and fly ash (FA) on the sorption of phosphate was studied in parallel experiments. The result shows that a higher efficiency of phosphate removal was acquired by the activated samples than by the raw ones. The sample prepared by using the RM stirred with 0.25 M HCl for 2h (RM0.25), as well as another sample prepared by heating the RM at 700 degrees C for 2h (RM700), registered the maximum removal of phosphate (99% removal of phosphate). This occurred when they were used in the phosphate sorption studies conducted at pH 7.0 and 25 degrees C with the initial PO(4)(3-) concentration of 155 mg P/l. The FA samples treated in the same way described above can achieve 7.0 and 8.2 mg P/l phosphate removal for FA0.25 and FA700 respectively, corresponding to 45.2% and 52.9% removal. The activated materials performed higher phosphate removal over broader pH range compared with the raw ones. The influences of various factors, such as initial pH and initial phosphate concentration on the sorption capacity were also studied in batch equilibration technique. Solution pH significantly influenced the sorption. Each sample achieved the maximal removal of phosphate at pH 7.0. The amount of phosphate removal increased with the solute concentration. The Freundlich and Langmuir models were used to simulate the sorption equilibrium. The results indicate that the Langmuir model has a better correlation with the experimental data than the Freundlich model.
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Affiliation(s)
- Yanzhong Li
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, PR China.
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