In this work, the ability of Romanian peat for sorption of Pb (II) ions from aqueous solution has been determined using the batch experimental techniques. The sorption equilibrium has been studied at different pH values. The equilibrium adsorption level was determined to be dependent of the pH of solution and initial Pb(II) concentration.The equilibrium adsorption capacity of Romanian peat sorbent for lead has been described by seven types of mathematical model isotherms, namely: Freundlich, Lan...
Autori: Brindusa Robu, Corneliu Cojocaru, Laura Bulgariu, Matei Macoveanu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25160

Include urmatoarele articole:� Keynote Lectures Energy from municipal solid waste: large-scale incineration or small-scale pyrolysis?� Electrical properties of SnO2-Pt/Al2O3 in reduction atmosphere� Corporate management tools to address sustainability Challenges. A reflection on the progress and difficulties experienced during the last decade� Emerging academic responsibilities and opportunities for promoting regional sustainability� Challenges for integrated water resources management...
Autori:
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25200

AbstractThis paper dealt with Cr(VI) sorption on isomorphic substituted Mg/Zn-Al - type hydrotalcites under proper working conditions. The prepared samples were named Mg3Al, Mg2ZnAl, Mg1.5Zn1.5Al, MgZn2Al and Zn3Al. The experimental data concerning sorption isotherms were modelled in accordance with four equilibrium equations: Langmuir (L), Freundlich (F), Langmuir-Freundlich (L-F) and Redlich-Peterson (R-P) by using two ways: (i) estimation of qmax, K and n; and (ii) estimation of K and n, for ...
Autori: Aurel Iovi, Eveline Popovici, Laura Cocheci, Rodica Pode
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25215

AbstractCadmium is listed by US-EPA as one of priority pollutant and as a known carcinogen, and therefore its removal from wastewaters of various industrial processes is a very important environmental problem. The paper analyzes the effectiveness of a Romanian sphagnum moss peat as available and cheaper sorbent in removal of Cd (II) from aqueous solutions. Batch sorption experiments were carried out in order to establish the influence of solution pH, peat dose, contact time and initial cadmium c...
Autori: Catalin Balan, , Matei Macoveanu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25231

AbstractEquilibrium and kinetic studies regarding the sorption of the copper phtalocyanine dye Alcian Blue 8 GX were carried-out within batch experiments. The sorption equilibrium revealed that the pure natural clay can uptake up to 18 mg of Alcian Blue 8 GX per 1 g mass of clay. The cationic dye sorption was best fitted by Freundlich model that is applicable to sorption on heterogeneous surfaces (surfaces with non-equivalent energetic sites). The pseudo-second order kinetic model may be efficie...
Autori: , Maria Gavrilescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25257

AbstractZeolites Cs+, Na+-chabazite with SiO2 /Al2O3 ratio of 7 were prepared from gels with molar composition (2.41-2.73)(Cs+ + Na+)2O : (0.02 TPAOH) : Al2O3 : 7.21 SiO2 : (194-204) H2O in static hydrothermal conditions at 108 – 132 0C for 8-21 days. The solids were characterized by X - ray diffraction, scanning electron microscopy, thermal analysis and nitrogen sorption measurements. The nitrogen sorption isotherms at -1960C present a hysteresis loop which is indicative for the existence of ...
Autori: Ionela Droahna, Iuliean Asaftei, Nicolae Bilba
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25266

AbstractNatural hemp fibers have been evaluated for Zn (II) ions sorption from diluted aqueous solutions. In order to establish the optimum conditions, the effect of initial pH of solution, hemp dose, Zn (II) concentration, temperature and contact time of phases on the Zn (II) sorption by natural hemp has been studied. To model the Zn (II) sorption at three different temperatures the Langmuir and Freundlich isotherms have been used. The Langmuir maximum sorption capacities were determined as bei...
Autori: Carmen Paduraru, Lavinia Tofan
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25336

AbstractTwo non-functionalized hypercrosslinked polymeric resins type Macronet (MN 202 and MN 250) were employed to remove nhexane vapors from gas phase. A comparison of the equilibrium behavior of these hypercrosslinked resins and a bituminous granular activated carbon was made. The initial n-hexane concentration in the air stream ranged from 2100 to 4500 ppm and the adsorption temperatures were 30oC, 40oC and 50oC. The results showed that the MN 250 presents the higher adsorption capacities of...
Autori: Adela Marilena Buburuzan Haleta, Cezar Catrinescu, Matei Macoveanu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25341

Abstract Peat moss has been widely used as low-cost adsorbent to remove a variety of pollutants, including organic compounds and metal ions from aqueous effluents. Various functional groups allow such compounds to bind on active sites of peat moss. The adsorbent used in this study was Romanian peat moss sampled from Poiana Stampei (Romania). The adsorption of Co(II) ions from aqueous solutions on Romanian peat moss was studied in batch experiments, in order to establish the influence of initi...
Autori: Corneliu Caramalau, Laura Bulgariu, Matei Macoveanu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25533

Abstract Chlorophenols are contaminants in soils, sediments, surface waters and groundwater, largely because of their worldwide utilization in the last 50 years as wood preservatives and general biocides in industry and agriculture. The toxicity of chlorophenols and their persistence in the environment require advanced treatment techniques for their removal. Surfactant-modified natural zeolites (SMZs) represent an important class of sorbents for water treatment. This work presents a comparat...
Autori: Roxana Elena Apreutesei, Cezar Catrinescu, Adrian Ungureanu,
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25537

Abstract Heavy metals produced and released by anthropogenic activities generate serious environmental problems. Ions of toxic metals can bind to the mineral surface in a number of ways, including absorption, adsorption, precipitation, ion exchange. The paper shows that the fate and migration of heavy metals in soils strongly depend on the physical properties and chemical and mineralogical composition of such environments. Cadmium is one of the most toxic metals with carcinogenic and teratog...
Autori: Vasile Lucian Pavel, Dumitru Bulgariu, Laura Bulgariu, Raluca Maria Hlihor, Maria Gavrilescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25577

Abstract The removal efficiency of Pb(II) from aqueous solutions by sorption on a bifunctional acrylic ion exchange resin with groups of hydroxamic acid and amidoxime is presented. It was found that Pb(II) sorption potential varies as function of solution pH, initial metal concentration, contact time and temperature. From aqueous solutions with Pb(II) initial concentration of 82.96 ?ŽÂ?g/mL the sorption percentage is 98.64%. The Langmuir and Freundlich isotherms were used to model the Pb(II) ...
Autori: Anca Ceica, Carmen Paduraru, Igor Creţescu, Lavinia Tofan, Violeta Neagu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25586

Abstract The use of biomaterials as biosorbents for treatment of wastewaters will provide as a potential alternate to the conventional treatment methods. The main advantages of biosorption are high selectivity , cost effectiveness and good removal performance. World wide numerous low cost bio materials have tried for biosorption of dyes. In this present investigation, the dead biomass of Penicillium sp. fungus and wood sawdust was used as biosorbents and their capacity to removed malachite gr...
Autori: Cornel Pohontu, Florin Luca, Igor Creţescu, Manea Liliana, Mariana Diaconu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25593

Abstract The aim of this study was to investigate the Congo Red (CR) sorption behavior onto six soils from Ia?…?¸i area, with different characteristics. The rate of sorption of Congo red dye molecules from aqueous solution by soil was studied in batch conditions. The rate of sorption was very rapid in the first 5-10 minutes and reached a maximum in 20 minutes. Kinetic modeling analysis of the pseudo-first-order, pseudo-second-order, intraparticle diffusion and Elovich equations reveals that t...
Autori: Camelia Smaranda, Dumitru Bulgariu, Maria Gavrilescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25594

Abstract The adsorption behavior of bael tree (BT) leaf powder for cadmium ions from aqueous solutions has been investigated as a function of appropriate equilibrium time, adsorbent dose, adsorbate concentrations and pH using a batch system. Studies showed that the pH of aqueous solutions affected cadmium removal as a result of the fact that removal efficiency increased with increasing solution pH. The maximum adsorption was 93.56% at solution pH equal to 6.0, contact time of 30 min and initi...
Autori: Ponnusamy Senthilkumar, Rangasamy Gayathri
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25621

Abstract Textile dyeing process is an important source of contamination responsable for the continous pollution of the environment. Control of water pollution has importance for both organisms, which live in water and those who benefit from water. Many dyes reaching the water source are difficult to decompose and cause many problems due to their carcinogenicity. Consequently, it is important to remove these pollutants from wastewater before their final disposal. This paper reports the resuls ...
Autori: Alina Dughila, Alina Stefanache, Cornel Pohontu, Igor Creţescu, Mariana Diaconu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25633

Abstract:Methyl orange and methylen blue are two dyes resulted from the textile industry. They are not raising just esthetical problems, butthey are toxic and hence harmful to aquatic animals. The aim of this study is to test the capacity of three types of sawdust (oak,willow and white poplar) and mixed substrates, sawdust: fly ash (FA), to remove the methyl orange (MO) and methylen blue(MB) from wastewater. The influence of contact time, solution pH and initial concentration of dyes on the blea...
Autori: Anca Duta, Dora Lucaci
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25752

Abstract:Coconut coir pith, an agricultural solid waste was used for the sorption of Cd (II) from aqueous solution in batch mode. Parameters like contact time, adsorbent dosage and pH effect were studied. Langmuir and Freundlich isotherms were used to model the adsorption equilibrium data and the system followed both the isotherms. Cd (II) adsorption capacity of coir pith was found to be 18.72 mg/g. Kinetic parameters of adsorption such as the Langergren pseudo-first-order, pseudo second order r...
Autori: Nagendra Badabhagni, Puthiya Veetil Nidheesh, Rajan Gandhimathi, Srikrishnaperumal Thanga Ramesh
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25800

The removal of Cr (VI) from aqueous solutions by sphagnum peat moss was investigated in batch experiments as a function of solution pH and initial Cr (VI) concentration. The highest removal percentage (R=99%) was obtained at pH = 1, in solutions of 20.8 mg Cr (VI)/L. In order to establish the mechanism of the removal process, Cr (VI) and total Cr (Cr (VI) + Cr (III)) in residual solutions was analyzed. The Cr (VI) removal by the peat moss at low pH is governed by two processes – electrostatic ...
Autori: Catalin Balan, Doina Bilba, Irina Volf, Matei Macoveanu, Petru Bulai
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25849

AbstractThe adsorption of hexachlorocyclohexane (HCH) by modified meerschaum was studied. The comparison of the meerschaummodified by anion and cation surfactant was conducted to explore their effect on HCH adsorption. The results showed that theabsorbability of HCH by the CTMAB-M (cetyltrimethylammonium bromide-modified) is better than that of SAS-M (sodiumdodecyl sulphonate-modified) because the CTMAB-M has fluffier fibers structure. The addition of amount of adsorbents shouldimprove the adsor...
Autori: Chanjuan Gao, Shengke Yang, Wenke Wang, Yaqian Zhao, Yue Zhao
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25948

AbstractThe removal of residual oil from palm oil mill effluent (POME) using boiler fly ash was studied in this paper, with focus on theadsorption isotherms and kinetic studies by measuring the residual oil concentration using UV-spectrophotometer. The percentresidual oil adsorbed decreased from 80% to 5% as contact time was increased from 10 mins to 120 mins but increased from2.74% to 72.98% as initial concentration of residual oil increased from 0.04812 mg/L to 0.2406 mg/L. Pseudo-second order...
Autori: Jude C. Igwe, Stella N. Anioke, Uche Arukwe
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26078

AbstractThe performance of four low cost Iraqi clays, bentonite (BT), kaolinite (KT), attapalgite (AT) and flint (FT) to remove lead ionsfrom aqueous solutions by adsorption was investigated. Batch experiments were carried out at pre determined equilibration time,adsorbent dosage, solution pH, particle sizes, ionic strength, initial lead ions concentration and temperature. Adsorption of Pb2+ions was strongly affected by pH and best adsorption is achieved at pH 4.5. The systems were investigated ...
Autori: Najwa I. Abdulla
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26086

AbstractThe removal of Acid Black 1 dye was investigated by acid treated pumice stone as a low cost adsorbent, since acidicmodifications were expected to improve the sorption capacity. The main components of the considered adsorbent were SiO2 andAl2O3 and acid treated pumice shows irregular structure. The effect of various parameters such as the initial dye concentration,the contact time, the temperature and the pH were studied. An increase of the contact time, the initial dye concentration or a...
Autori:
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26211

AbstractAdsorption of a cationic dye, methylene blue, from aqueous solutions by using sawdust (without any modification) by batchadsorbers was investigated. The surface characterization of the saw dust was carried out by Fourier transform infrared (FTIR) andscanning electron microscopy (SEM) and pHzpc of the surface was also determined. Effects of different parameters such ascontact time and initial concentration, temperature and pH on the process of removal were studied. The process of removal ...
Autori: Sushmita Banerjee
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26216

AbstractLow water quality due to high levels of ammonia, chemical oxygen demand (COD), abnormal pH, and undesirable water color isprevalent in many prawn ponds in Malaysia. A composite medium used in the treatment of prawn pond effluent was examinedfor the reduction of undesirable parameters. The composite medium is a mixture of limestone, activated carbon, zeolite, and ricehusk. Experiments were conducted under three different conditions, i.e., sole aeration, adsorption, and adsorption with pre...
Autori:
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26219

AbstractThe extent of the problem of the excessive fluoride in drinking water remains an important health issue. In the present work,strong-base anion resins were investigated to assess their sorptive removal capacity of fluoride from water. It was found that theremoval of fluoride was high at natural pH (7) and was improved for increasing contact time and adsorbent dosage. Themaximum sorption of the resin was 13.7 mg/g according to the Langmuir model, namely higher than the values reported in t...
Autori: Mohammad Taghi Samadi
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26273

AbstractHexavalent chromium can contaminate drinking water resources and should therefore be removed from industrial waste effluents. The use of ion exchange resin was examined in batch tests to remove Cr (VI) from acidic solution by Amberlite IRA 410. Equilibrium data were analyzed and modelled using Freundlich and Langmuir adsorption isotherms and the results showed that the adsorption behaviour of Cr (VI) could be accurately described by means of a Langmuir model. The monolayer adsorption cap...
Autori: Abdeltif Amrane, Aicha Bensmaili, Malika Chabani, Yasmine Ait Ouaissa
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26289

AbstractThis paper presents the results of the removal of arsenite and arsenate ions from an aqueous solution using Fenton modified solid waste vegetable oil industry (SWVOI). Several factors (such as pH, contact time and Fe2+/H2O2 ratio, initial arsenic ion concentration and adsorbent concentration) that affect the arsenic ion adsorption on the SWVOI adsorbent material were investigated. The sorption characteristics of the adsorbent material before modification were also studied and compared wi...
Autori: Hoda Amiri, Mehdi Ahmadi, Nemat Jaafarzadeh, Susana Silva Martínez
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26290

AbstractThis study focus on the possibility of removing the basic textile dye Astrazon Blue FGGL 300% 03, from an aqueous solution, using Esmegel clay as adsorbent. The characterization of the adsorbent included the distribution of particle size, physical textural properties, chemical composition and determination of the point of zero charge. The equilibrium isotherms were determined at 20 and 30 °C, pH at 6.0 and 7.5 and adjusted to the Langmuir and Freundlich models, having the latter led to b...
Autori: Chia-Yau Cheng, Paula M.S.S. Luís, Rui A. R. Boaventura
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26292

AbstractIn the present study, batch adsorption experiments were performed for the removal of methylene blue (MB) dye from its aqueoussolution using newly prepared surface modified cashew nut shell (SMCNS) by varying the operating parameters like solution pH,adsorbent dose, initial dye concentration, contact time and temperature. The SMCNS has been prepared by treating the cashewnut shell with the sulphuric acid. Adsorption equilibrium data were analyzed by the model equations such as Langmuir,Fr...
Autori: Krishnan Gayathri Lashmi, Muthukumar Priyadharshini, Ponnusamy Senthil Kumar, Ramasundaram Vijayakumar Abhinaya, Subramanian Sivanesan, Vishwanathan Arthi
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26309

AbstractThe removal and determination of toxic heavy metal ions in aqueous solutions has been given much more attention over the pastfew years. In this paper, a removal and separation/preconcentration method for cadmium species on Poly S15-g-EMA100 (a kind ofpolystyrene-graft-ethyl methacrylate copolymer) in water samples was developed. Some experimental parameters, such assolution pH, sample flow rate, type and concentration of eluent, amount of adsorbent and effect of common matrix ions werein...
Autori: Harun Ciftci
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26317

AbstractThe biosorption equilibrium isotherms of copper ions from wastewater onto date stones (DS) and palm-trees Waste (PTW) inaqueous solution over a range of temperatures between 25 and 70°C were studied and modelled. To predict the biosorptionisotherms and to determine the characteristic parameters for process design, five models frequently used in the literature -Langmuir, Freundlich, Temkin, Sips and Redlich-Peterson were applied to experimental data.The Langmuir’s model gives the most acc...
Autori: Fatiha Mechati, Fatima Addoun, Mejdi Jeguirim, Meriem Belhachemi, Zohra Belala
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26319

AbstractThe possible recovery of three microelements contained in the sludges resulted after chemical leaching of uranyl ions fromuranium ores was investigated, using four types of zeolites as adsorbents. The variation of the retention degree in time of 3cations: Fe3+, Ti4+ and Ni2+, adsorbed on: ETS-10, ETS-4, ZSM-5 and mordenite was followed. The characteristic adsorptionparameters connected to Langmuir and Freundlich isotherms were also determined. For a given adsorbent, the rate of globalret...
Autori: Alexandru Cecal, Dumitru Gânju, Maria Ignat, Nicoleta Melniciuc-Puica, Petrisor Mugurel Samoila
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26327

AbstractThe biosorption characteristics of Cd(II) ions using the NaCl-treated Ceratophyllum demersum were studied. The effect ofaltering the conditions, such as solution pH, the biosorbent dosage and contact time for the biosorption of Cd(II), and thebiosorption/desorption studies, were investigated. Langmuir, Freundlich, Dubinin-Radushkevich and Redlich–Peterson modelswere applied to describe the biosorption isotherms. Langmuir model fitted the equilibrium data better than the other isotherms(R...
Autori: Ali Akbar Babaei, Mehdi Ahmadi, Nadali Alavi, Nemat Jaafarzadeh, Pari Teymouri
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26331

AbstractGuazuma ulmifolia seeds activated carbon was modified by sulphuric acid to enhance the adsorption capacity for Cu(II) ions.This modified activated carbon produced from Guazuma ulmifolia seeds (GUAC) was investigated by observing the changes inits characteristics and the Cu(II) adsorption behavior. The prepared GUAC was characterized by BET, FTIR and SEM analysis.The kinetic data were analyzed using four adsorption kinetic models: the pseudo-first and pseudo-second order equations,intrapa...
Autori: Muthukumar Priyadharshini, Palanichamy Baskaralingam, Palanichamy RajKumar, Ponnusamy Senthil Kumar, Selvaraj Dinesh Kirupha, Subramanian Sivanesan
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26344

AbstractThe adsorption potential of 10 wt.% COOH/TUD-1 material for removing Cd2+ from aqueous solutions was investigated via thebatch technique, and the effects of pH, temperature and contact time were studied. Experimental data showed that the maximumCd2+ adsorption, 90%, occurred at pH 6. The adsorption equilibrium was reached within 35 min for 10 wt.% COOH/TUD-1. Theadsorption mechanism was investigated in terms of its thermodynamics and kinetics. The adsorption data were fitted using theLan...
Autori: Nabila Bensacia
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26558

AbstractGraphene oxide (GO) was prepared from expandable graphite by a modified Hummers’ method and characterized by TEM,XRD, FTIR, and Raman spectroscopy. The batch adsorption experiments were carried out to study the effect of variousparameters, such as the initial concentration, adsorbent dosage, initial pH, contact time and temperature on adsorption propertiesof cationic red X-GRL onto GO. The Langmuir and Freundlich models were used to fit the experimental data of adsorptionisotherms. The k...
Autori: Jiankun Sun
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26570

Abstract The present study deals with the removal of Cr (VI) from aqueous solution by polypyrrole (PPy). Response surface methodology (RSM) was applied for the design and analysis of experiments in the optimization of pH, temperature, initial concentration, contact time and adsorbent dose during the removal of the Cr (VI). The optimum adsorbent dose, temperature, initial concentration of Cr (VI), pH and contact time were found to be 0.8 g, 46.5 oC, 187.5 mg/L, 5.3 and 15.4 min respectively. ...
Autori: Ehsan Hasani
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26614

Abstract Activated carbon was prepared from renewable plant material, that is Euphorbia rigida, by chemical activation using zinc chloride as activating reagents. The adsorption of Basic Blue 9 (BB9) onto activated carbon was investigated in a batch system with respect to contact time, pH and temperature from aqueous solutions. The experimental data indicated that the adsorption isotherms are well described by the Langmuir isotherm model and the calculated maximum adsorption capacity of acti...
Autori: Özgül Gerçel
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26627

Abstract The present work investigates the performance of Cristal-RightTM CR100 zeolite based on the equilibrium and thermodynamics water softening process. The commercial zeolite was characterized by scanning electron microscopy combined with energy dispersive X-ray spectroscopy and FT-IR spectroscopy. The equilibrium performances of zeolite were evaluated by the sorption capacity of calcium cations from calcium chloride solutions varying the calcium concentrations corresponding to moderate...
Autori: Liliana Lazăr
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26670

Abstract Adsorption has proved to be an excellent way to treat industrial wastewater, due to its significant advantages like easy availability, inexpensive, ease of operation and highly efficient, compared to conventional expensive adsorbents like activated charcoal, alumina etc. The present investigation focused on utilization of Mangifera indica seed shell substrate for the removal of toxic heavy metals like Fe(II) and Mn(II) from wastewater. Mangifera indica seed shell substrate as an eff...
Autori: Tikaram D. Kose
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26713

Abstract Maximum removal (94±1.2%) of 2, 4 dichlorophenol (50 mg.dm-3) was achieved on silica with agitation of 4 hours, at pH 8 and 42°C. The positive enthalpy (ΔH) and negative free energy values (ΔG315K) suggested the endothermic and a spontaneous nature of sorption. The free energy of the process at all temperature was negative and increased with the increase in temperature. The values of free energy suggested a spontaneous process where the spontaneity decreased w...
Autori: Abdul Ghaffar
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26718

Abstract This study was carried out to investigate the adsorption of methylene blue (MB) onto pumice powder, as a low-cost adsorbent for the removal of dyes. The experiments were designed based on a central composite design (CCD) and the process was analyzed and modeled using response surface methodology (RSM). In order to study the adsorption process, three important factors viz. pumice dosage (20- 50 mg/50mL), MB concentration (20-40 mg/l) and contact times (5- 35 min) were chosen as varia...
Autori: Kiomars Sharafi
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26729

Abstract The aim of this study is to evaluate adsorption kinetics, isotherms and thermodynamic parameters of anionic textile dye (Acid Red 88) onto montmorillonitic clay from aqueous solutions. The parameters of pH, initial dye concentrations, temperature, and the adsorbent dosage were investigated experimentally. Four kinetic models including pseudo-second order, pseudo-nth order, Bangham’s equation and double exponential equation (DEE) were selected to follow the adsorption process. ...
Autori: Sedef Dikmen
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26731

Abstract Chitosan and keratin were tested as low cost biosorbents to remove phenol from water solutions at variable temperature (20- 50°C), initial phenol concentration (10-90 mg L-1) and pH (5.0-10.0), and fixed biosorbent dosage (10 g L-1). The pseudo-second order kinetic model exhibited the best fit to the experimental data and allowed estimating theoretical values of sorption capacity of 4.51 mg g-1 with keratin and 2.87 mg g-1 with chitosan. Equilibrium isotherms, described at best ...
Autori: Attilio Converti
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26743

Abstract In this study, activated carbon was synthesized from durian peel and used for the removal of lead (II) ions from water. The activated carbon was produced with physical activation method using CO2 as the activating agent at 900 oC. Prior to the activation process, durian peel was carbonized under either nitrogen atmospheric or vacuum pyrolysis in order to compare the properties of the synthesized activated carbons. Suitable adsorption kinetics and isotherm models for the lead (II) re...
Autori: Samorn Hirunpraditkoon
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26901

Adsorptive removal of dibutyl phthalate (DBP) by bamboo biochar (BC) was investigated under various experimental conditions. BC demonstrated excellent sorptive ability to remove DBP from the aqueous solutions. The removal of DBP by BC increased as the contacting time increased and reached an equilibrium value after 240 min. The presence of natural organic matter decreased the removal efficiency while increased the time to reach sorption equilibrium. The adsorption of DBP on BC could be well ...
Autori: Junliang Wang
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26934

The release of nitrogen compounds into the environment is a major concern worldwide. Different studies howed that recycled materials have a high removal capacity for pollutants. Bentonite and its major clay minerals, smectites clays are common bleaching agents used for oil refinery bleaching and known as bleaching earth (BE). In this study regeneration of spent bleaching earth (SBE) acquired from the vegetable oil industry was surveyed via different methods and the regenerated spent bleaching...
Autori: Mohammad Malakootian
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27000

In this study the immobilized waste black tea (Camellia synensis) was used as biosorbent for the removal and recovery of Al(III) and Cr(VI) ions from the synthetic aqueous solutions. Batch experiments were conducted to optimize the various biosorption parameters that affect the biosorption capacity of immobilized waste black tea. Maximum biosorption capacity was found with a biosorbent dose of 0.1g/100 mL for both metal ions. Optimum biosorption capacity for both Al(III) and Cr(VI) ions was o...
Autori: Haq Nawaz Bhatti
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27004

The arsenic removal from aqueous medium was investigated through adsorption by employing finely powdered bark of Pinus roxburghii Sarg. The batch mode laboratory scale experiments were conducted to investigate the removal efficiency of Pinus bark against total arsenic and the effect of pH, contact time, adsorbent dose and initial adsorbate concentration on adsorption to optimize the process. Langmuir and Freundlich isotherms were used to validate the adsorption data and respective constants w...
Autori: Syed Hasnain Shah
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27013

Removal of Cd(II) from aqueous streams is of special concern because of its very high toxicity and persistent nature. The sorbents based on natural and waste materials have very promising performances in the treatment of Cd(II) contaminated waters. Very few reviews are available that provide valuable information on the various aspects of the utilization of natural and waste materials for Cd(II) metal ions removal. In this context, this review examines a wide range of materials as green sorben...
Autori: Lavinia Tofan
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27033

This work evaluates the potential of Phyllanthus debilis for the adsorption of Zn2+ and Ni2+ ions using synthetic solutions. Adsorption experiments were performed in order to examine the effect of pH, contact time, biomass concentration and initial metal ion concentration in the removal process, in a batch mode. The results revealed that the adsorption is highly pH dependent. The adsorption of Zn2+ and Ni2+ ions were concentration dependent and increased from 2.446 to 8.688 mg/g for Zn2+ and ...
Autori: Mohammad Aslam
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27084

In this study, the impact of silicate admixture in 2-line ferrihydrite on its sorption properties is presented. Synthetic ferrihydrites with broad Si content in the range of 0 to 1.5 Si/Fe molar ratios were prepared and characterized using X-ray diffractometry (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM-EDS). With an increase in the Si/Fe ratio, a typical XRD peak at 2.5Å broadens and shifts toward 3 Å; the position of Si-O stretchi...
Autori: Gabriela Pieczara
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27140

Dried Typha angustifolia (TA) leavesor commonly known as the common cattail were evaluated as an adsorbent for the adsorption of lead in synthetic aqueous solutions. Equilibrium studies were conducted in a batch mode and the selected sorption isotherms were then applied. Equilibrium was achieved after 8 hours. The selected sorption isotherms were the Langmuir, Freundlich, D-R and Temkin model. Data fitting was done based on linear regression analysis. The adsorption system fitted the Langmui...
Autori: Yen Ling Sharain-Liew
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27166

Equilibrium and kinetics of biosorption of lead(II) from aqueous solutions by local low-cost agricultural by-products – peanut hulls, soybean shells and grapefruit peels were compared to develop high-efficient and low-cost biosorbents for removal of lead(II) from wastewater. Batch kinetics showed adsorption equilibrium at about 90 min and the adsorption process for the three biosorbents was better represented by the pseudo-second-order model than the pseudo-first-order model. Batch equilib...
Autori: Rui Yu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27176

In this study, chitosan-iron(III) was used as adsorbent of the dye acid red 29. The effect of pH, temperature and concentration of the dye on the adsorption capacity were evaluated. The maximum adsorption capacity was calculated from the adsorption isotherms which were well fitted by Sips isotherm model. The process followed the kinetic model of pseudo-second-order. The activation parameters showed that the adsorption process is spontaneous and favorable. A decrease in adsorption capacity was ob...
Autori: Carla Albertina Demarchi
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27181

The adsorption of tartrazine from aqueous solution was evaluated using an iron (III) modified zeolitic tuff. The adsorbent was characterized by scanning electron microscopy and X-ray power diffraction; the modification process does not affect the crystalline structure of the zeolitic tuff. Sorption kinetic, isotherms, dose and pH effects were determined and the adsorption behavior was analyzed. The sorption equilibrium was reached in 72 hours, the adsorption capacity determined by the Langmuir m...
Autori: Adrián Alcántara-Cobos
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27182

The adsorbent gels utilized in this research project were synthesized from non-commercially available chitosan, obtained by deacetylation of chitin, which was isolated from fermented shrimp waste by a major local industrial food biopolymer. Chitosan-based adsorbent gels were used for the removal of a tris-azo dye (Direct Blue 71) from aqueous solutions. Sorption experiments focused on the chemical modification of chitosan using two cross-linking agents, sodium tripolyphosphate (TPP) and glutaral...
Autori: Reyna G. Sánchez-Duarte
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27184

Various azodyes containing one or more sulfonic groups were removed from aqueous solutions by biosorption on untreated wood shavings from Picea abies. The sorption kinetics was described by the pseudo-first-order (PFO), pseudo-second-order (PSO) and modified pseudo-n-order (MPnO) equations, from which the MPnO model provided the best fit to the experimental data. The surface reaction was identified as a rate-limiting step governing the dye sorption on wood shavings, but a mixed kinetics (with a ...
Autori: Pavel Janoš
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27207

Date pits were used as a low-cost adsorbent to study the effective removal of copper (II) ions in an aqueous solution on the basis of adsorption kinetics and isotherm equations. Before and after the adsorption process, the date pits were characterized by electron scanning microscope (ESM) as well as Infrared spectroscopy (IR). The effects of the pH, zero point of charge, the adsorbent mass, and the adsorbent particle size on the adsorption of copper (II) were also studied. Equilibrium data were ...
Autori: Tarek E. Khalil
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27212

The paper aims to present the sorption properties of two sorbent substrates (composts) prepared by aerobic fermentation from vegetables waste composted with beech sawdust (BR2) and beech ash (BC1) to be used for Cu2+ removal from wastewaters. The composts structures and surface properties were characterised in terms of active groups (FTIR), crystallinity (XRD), morphology (SEM), topography (AFM) and specific surface and pores analysis (BET), and the changes in properties after Cu2+ sorption were...
Autori: Ileana Manciulea
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27323

Effective adsorbents were developed from sewage sludge by chemical activation with different activators (5M ZnCl2, 3M H2SO4, 3M H3PO4, 5M ZnCl2: 3M H2SO4, and 5M ZnCl2: 3M H3PO4). The developed adsorbents were used for the removal of the heavy metals Cd (II), Pb (II), Cu (II) and Mn (II) from wastewater. The effect of several parameters (pH, initial metal ion concentration, adsorbent dose, contact time and solution temperature) on the metal adsorption capacity were evaluated by batch experiments...
Autori: Mohamed Nageeb Rashed
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27385

Three modified bentonites, hydroxy-aluminum pillared bentonite (Al(OH)-Bent), cetyl trimethylammonium bromide modified bentonite (CTAB-Bent), and both cetyl trimethylammonium bromide and hydroxy-aluminum modified bentonite (Al(OH)-CTAB-Bent) were prepared and characterized by Fourier transform infrared spectroscopy (FTIR) analysis. Batch experiments were conducted on the adsorption of phenol at different temperatures, pH and initial concentration. The results indicated that adsorption capacity o...
Autori: Xiping Luo
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27481

A new low-cost activated carbon was developed from kiwi peel for removing Pb(II) from aqueous solution. The adsorbent characteristics were determined by different analyses such as BET, FTIR and SEM. The adsorbent demonstrated remarkable characteristics such as high surface area (306.18 m2.g-1) and large total pore volume (0.4810 cm3.g-1). The effect of pH, contact time, initial concentration, shaking rate and adsorbent dosage on the Pb removal efficiency was investigated. It was found that the o...
Autori: Mostafa Rahimnejad
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27605

The native and surface modified adsorbents from agricultural waste, such as Psyllium stalks (PS) were investigated for their ability to remove the Coomassie Brilliant Blue (CBB) dye from aqueous media. The native and surface modified adsorbents were characterized by the Fourier Transform Infrared spectroscopy (FTIR). The results show that the Sodium Bicarbonate Treated Carbon (SBTC) has good surface properties for the removal of the CBB dye from aqueous media. The SBTC was analyzed by Scanni...
Autori: Premkumar Manickam Periyaraman
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27898

The theoretical and computational studies of dye sensitized solar cells (DSSCs) can contribute to a deeper understanding of these types of solar cells. The DSSCs are the novel design of solar cells which could be used as power producing windows or skylights. They represent a particular promising approach to a direct conversion of sunlight into electrical energy at low cost and with high efficiency. The light adsorption occurs in dye molecules adsorbed on a highly porous structure of TiO2 film...
Autori: Nnditshedzeni Eric Maluta
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27932

To produce drinking water, the water treatment plants generate huge quantities of sludge, this sludge is a waste and they are evacuated to the dump. The valuation of these sludge will be benific This study focuses on the development of composite alginates beads and sludge activated chemically by sulphuric acid and thermally for the removal of dyes from aqueous solutions. Two dyes were studied; a basic cationic dye (methylene blue) and an acidic anionic dye (Congo red) to compare the adsorption m...
Autori: Hasna Elmontassir
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28125

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Autori: Matthew Maya
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28145

As CO2 concentration levels in the atmosphere are steadily reaching a point of no return, it is paramount that actions are taken towards mitigating emissions by improving the efficiency of existing processes. Sorption-enhanced water-gas shift (SEWGS) combines the water-gas shift reaction with in-situ adsorption of CO2 on potassium-promoted hydrotalcite (K-HTC). This enables a direct conversion of syngas into separate hot streams of H2 at feed pressure and CO2 at regeneration pressure, making th...
Autori: Vlad-Cristian Sandu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28149

In this work, the removal of methyl orange (MO) and Cd2+ by simultaneous adsorption on adsorbent obtained from modified charcoal (BCBH) coated with TiO2 has been studied. The synthesized materials obtained from wood branches were characterized using atomic force microscopy (AFM) for the roughness and SEM to determine the morphology of the surface. EDX spectroscopy indicates the presence of C, N, O, Na, K, P and Ti on the surface of the adsorbent materials. The micro-porosity and BET specific sur...
Autori: Nicoleta Popa
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28157

Release of dyes without performing adequate treatment into the water can lead to environmental risk and serious health problems. The development of effective and economic adsorbent materials for the removal of dyes from industrial wastewaters has gained great consideration in recent years. In the present study, a novel bio-based nanocomposite has been developed for ultrasoundassisted adsorption of malachite green (MG) from aqueous solutions. The synthesized adsorbent consisting of both hydropho...
Autori: Mohsen Nekoeinia
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28232