scispace - formally typeset
Journal ArticleDOI: 10.1080/01496395.2017.1323923

Removal of Fe(III) from synthetic wastewater into raw and modified clay: Experiments and models fitting

04 Mar 2021-Separation Science and Technology (Taylor & Francis)-Vol. 56, Iss: 4, pp 708-718
Abstract: Water pollution by heavy metal ions has become a serious environmental issue especially due to their toxicity and tendency to bioaccumulation. Natural smectite clay was treated using sulfuric acid ...

... read more

Topics: Wastewater (55%), Bioaccumulation (52%), Water pollution (52%)

8 results found

Journal ArticleDOI: 10.1016/J.JCLEPRO.2019.118189
Abstract: Chitosan-based nanocomposites are considered to be promising candidates to for application in water treatment technology due to their distinguished physicochemical properties. In the present work, a new melamine grafted chitosan nanocomposite has been synthesized as an effective material for ferric ions adsorption. The nanocomposite has been synthesized via graft polymerization of chitosan using glutaraldehyde/epichlorohydrin crosslinkers in the presence of 0.1% of Nano-Montmorillonite (w/w % based on chitosan). Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques have been utilized for the characterization of the synthesized nanocomposite. Central composite design (CCD) of response surface methodology (RSM) has been applied for determination of the optimum conditions for the adsorption of ferric ions. Under the optimum conditions, the nanocomposite shows 99.97% for ferric ions removal percent with good reusability till third cycle. Kinetic, isothermal, and thermodynamic analyses have been studied to have deep insights into the mechanism of ferric ions adsorption on the synthesized nanocomposite.

... read more

Topics: Nanocomposite (56%), Adsorption (54%), Ferric (53%) ... show more

30 Citations

Journal ArticleDOI: 10.1016/J.JCLEPRO.2020.123935
Abstract: A natural clay material from southern Tunisia was used as a low cost sorbent in a column-wise removal of metal pollutants. This is fundamentally important for a sustainable wastewater treatment strategy. This work has been performed within the framework of a project aiming to the valorization of natural geomaterials, from Tunisia, in several environmental applications. Column adsorption experiments were carried out for a better production of cleaner effluents and further understanding of the main mechanisms involved in the removal process, through a dynamic methodology, that would allow an industrial scale treatment. A calcined clay sample was used as an adsorbent for the removal of Pb(II), Cr(VI) and Cd(II) from aqueous solution. Lead removal, in presence of copper and zinc, was also studied. The effect of various parameters including bed height (2.0, 4.0 and 6.0 cm), flow rate (3, 5.8 and 9 mL/min) and influent metal ion concentrations (50, 100 and 150 mg/L) were investigated at an influent pH of 6. It was found that the exhaustion time increased with the increase of bed depth, the decrease of flow rate and initial concentration. Bohart -Adams, Thomas, Yoon–Nelson and Advection diffusion models were applied to the experimental data to predict the breakthrough curves for a better understanding of the main adsorption mechanisms. The assessment of the calcined clay performance may further explain the mechanism of metals-sorbent interaction at the water-clay interface. Thomas and Advection diffusion models were in good agreement with the experimental data. Column-wise packing of clays achieved excellent adsorption performances of metal ion in aqueous solution. The obtained results suggested a possible extension to the industrial scale of the fixed bed adsorption systems for cleaner water production, especially in the southern Tunisian districts where uncontrolled effluents discharge needs an immediate application of monitoring programs to for a sustainable improvement of water quality.

... read more

Topics: Adsorption (54%)

13 Citations

Open accessJournal ArticleDOI: 10.3390/TOXINS11100602
Roua Rejeb1, Roua Rejeb2, Gunther Antonissen2, Marthe De Boevre2  +6 moreInstitutions (3)
16 Oct 2019-Toxins
Abstract: Clays are known to have promising adsorbing characteristics, and are used as feed additives to overcome the negative effects of mycotoxicosis in livestock farming. Modification of clay minerals by heat treatment, also called calcination, can alter their adsorption characteristics. Little information, however, is available on the effect of calcination with respect to mycotoxin binding. The purpose of this study was to characterize a Tunisian clay before and after calcination (at 550 °C), and to investigate the effectiveness of the thermal treatment of this clay on its aflatoxin B1 (AFB1), G1 (AFG1), B2 (AFB2), G2 (AFG2), and zearalenone (ZEN) adsorption capacity. Firstly, the purified clay (CP) and calcined clay (CC) were characterized with X-ray Fluorescence (XRF), X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR-IR), cation exchange capacity (CEC), specific surface area (SBET), and point of zero charge (pHPZC) measurements. Secondly, an in vitro model that simulated the pH conditions of the monogastric gastrointestinal tract was used to evaluate the binding efficiency of the tested clays when artificially mixed with aflatoxins and zearalenone. The tested clay consisted mainly of smectite and illite. Purified and calcined clay had similar chemical compositions. After heat treatment, however, some changes in the mineralogical and textural properties were observed. The calcination decreased the cation exchange capacity and the specific surface, whereas the pore size was increased. Both purified and calcined clay had a binding efficacy of over 90% for AFB1 under simulated poultry GI tract conditions. Heat treatment of the clay increased the adsorption of AFB2, AFG1, and AFG2 related to the increase in pore size of the clay by the calcination process. ZEN adsorption also increased by calcination, albeit to a more stable level at pH 3 rather than at pH 7. In conclusion, calcination of clay minerals enhanced the adsorption of aflatoxins and mostly of AFG1 and AFG2 at neutral pH of the gastrointestinal tract, and thus are associated with protection against the toxic effects of aflatoxins.

... read more

Topics: Calcination (57%), Clay minerals (53%), Bentonite (52%) ... show more

8 Citations

Journal ArticleDOI: 10.1007/S13762-019-02614-X
Abstract: The present study has been carried out for potential use of a raw clay from Gabes district (southern Tunisia) in wastewater treatment. A representative clay sample was collected from the outcropping feature of the Aidoudi area to the west of Gabes city; it followed a simple treatment to enhance its physicochemical properties. Adsorption experiments were performed by using a simple batch technique in single- and multi-element solution (Pb2+, Cd2+, Cu2+ and Zn2+). The obtained results were fitted to different adsorption models, including extended and modified Langmuir, extended Freundlich and modified Redlich–Peterson. Our results indicated that the collected clay sample is mainly a smectite with high amounts of silica, alumina and iron. Adsorptive removal of single elements revealed encouraging efficiencies for most of the studied metals, reaching nearly 100%. Our results also indicated that lead removal reached 26.78 mg/g and 45.94 mg/g for natural and activated clay samples, respectively. Competitive adsorption showed strong dependence on the initial concentration and the metal properties, with preferential removal of lead that reached 41.71 mg/g in binary systems. In most of the mixed systems, metal removal substantially decreased in the presence of competing ions. It showed preferential removal of lead over other metals, regardless of the studied mixture. Further, the use of smectitic clay from southern Tunisia showed a good potential for metal ions removal in single and multi-element systems from aqueous solutions. Thus, it could be turned out to a viable material for the treatment of metal loaded waters.

... read more

Topics: Freundlich equation (54%), Adsorption (52%), Langmuir (51%) ... show more

5 Citations

Open accessJournal ArticleDOI: 10.1049/MNL.2018.5364
Abstract: Bentonite clays containing mostly montmorillonite as a nanostructure group of smectite have been used as industrial raw material in many applications. The presence of the other impurities in bentonite clays reduces the value of bentonite. Therefore, the bentonite purification is necessary. In this research, the purification and separation of montmorillonite from a low-grade natural bentonite were considered on the regular and comprehensive plan. For this purpose, a set of methods including dispersion, sodium-activation, sedimentation, sonication and centrifugation were used. In contrast to many methods, there were often complex, expensive and non-effective; this purification method was found to be effective for removing almost all quartz, carbonates and clinoptilolite as the major impurities. In this purification method, the montmorillonite content was increased from 15 to 84% with the separation yield of 80%. The influence of centrifugal force and the type of ultrasonication indicated the most critical parameters in the purification yield, the physical properties and the crystalline structure of the final products. The laser particle size distribution analysis, X-ray diffraction, semi-quantitative analysis and Fourier-transform infrared spectroscopy results showed the decrease of impure phase without any structural changes or damages in clay framework.

... read more

Topics: Bentonite (59%), Montmorillonite (58%)

5 Citations


29 results found

Journal ArticleDOI: 10.1016/J.CIS.2007.12.008
Abstract: The feasibility of using two important and common clay minerals, kaolinite and montmorillonite, as adsorbents for removal of toxic heavy metals has been reviewed. A good number of works have been reported where the modifications of these natural clays were done to carry the adsorption of metals from aqueous solutions. The modification was predominantly done by pillaring with various polyoxy cations of Zr4+, Al3+, Si4+, Ti4+, Fe3+, Cr3+or Ga3+, etc. Preparation of pillared clays with quaternary ammonium cations, namely, tetramethylammonium-, tetramethylphosphonium- and trimethyl-phenylammonium-, N′-didodecyl-N, N′-tetramethylethanediammonium, etc, are also common. Moreover, the acid treatment of clays often boosted their adsorption capacities. The adsorption of toxic metals, viz., As, Cd, Cr, Co, Cu, Fe, Pb, Mn, Ni, Zn, etc., have been studied predominantly. Montmorillonite and its modified forms have much higher metal adsorption capacity compared to that of kaolinite as well as modified-kaolinite.

... read more

Topics: Montmorillonite (56%), Adsorption (54%), Kaolinite (53%) ... show more

1,131 Citations

Journal ArticleDOI: 10.1016/S0304-3894(00)00278-8
Bin Yu, Y Zhang, Alka Shukla, Shyam S. Shukla1  +1 moreInstitutions (1)
Abstract: Locally available sawdust, a byproduct of the world industry, was found to be a low cost and promising adsorbent for the removal of copper(II) from wastewater. In this work, adsorption of copper on sawdust has been studied by using batch techniques. The equilibrium adsorption level was determined to be a function of the solution pH, contact time, and sorbate concentration. The equilibrium adsorption capacity of sawdust for copper was obtained by using linear Freundlich and Langmuir isotherms. Ion exchange is probably one of the major adsorption mechanisms for binding divalent metal ions to the maple sawdust. The results provide strong evidence to support the hypothesis of adsorption mechanism. It also supplies significant sawdust operation capacity data for engineering design.

... read more

Topics: Freundlich equation (63%), Sawdust (60%), Adsorption (59%) ... show more

492 Citations

Journal ArticleDOI: 10.1016/J.BIORTECH.2011.11.110
Suhong Chen1, Qinyan Yue1, Baoyu Gao1, Qian Li1  +2 moreInstitutions (1)
Abstract: Continuous fixed-bed column studies were carried out by using modified corn stalk (MCS) as an adsorbent for the removal of Cr(VI) from aqueous solution. The effect of various parameters like bed depths (1.4, 2.2 and 2.9 cm), flow rate (5, 10 and 15 mL/min), influent Cr(VI) concentrations (100, 200 and 300 mg/L) and influent solution pH (2.66, 4.91 and 5.66) was investigated. The exhaustion time increased with increase of bed depth, decrease of flow rate and influent concentration. The Adams–Bohart, Thomas and Yoon–Nelson models were applied to the adsorption under varying experimental conditions to predict the breakthrough curves and to evaluate the model parameters of the fixed-bed column that are useful for process design. The Thomas and Yoon–Nelson models were in good agreement with the experimental data. The MCS column study states the value of the excellent adsorption capacity for the removal of Cr(VI) from aqueous solution.

... read more

Topics: Adsorption (50%), Aqueous solution (50%)

335 Citations

Journal ArticleDOI: 10.1016/J.MOLLIQ.2014.09.027
Abstract: A novel adsorbent, copper oxide nanoparticle loaded on activated carbon (CuO-NP-AC) was synthesized by a simple, low cost and efficient procedure. Subsequently, this novel sorbent was characterized and identified using different techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and laser light scattering (LLS). The effects of some variables including pH, adsorbent dosage, initial dye concentration, contact time and temperature were examined and optimized. The adsorption kinetic data were modeled using the pseudo-first-order, pseudo-second order, intraparticle diffusion and Elovich models, respectively. The experimental results indicated that the pseudo-second-order kinetic equation can better describe the adsorption kinetics. Furthermore, Langmuir, Freundlich, Tempkin and Dubinin–Radushkevich models were applied for analyzing adsorption equilibrium data of acid blue 129 (AB 129) on the as-prepared adsorbent, which suggested that the Langmuir model provides a better correlation of the experimental data. Also, thermodynamic parameters such as ΔH, ΔS, Ea, S*, and ΔG were calculated. It was seen that the proposed adsorbent has high tendency and adsorption capacity for AB 129 adsorption in a feasible, spontaneous and endothermic way.

... read more

Topics: Freundlich equation (66%), Langmuir adsorption model (60%), Adsorption (59%) ... show more

297 Citations

Journal ArticleDOI: 10.1016/J.WATRES.2003.11.022
Pankaj Sarin1, Vernon L. Snoeyink1, J. Bebee1, K.K. Jim1  +3 moreInstitutions (2)
01 Mar 2004-Water Research
Abstract: Iron release from corroded iron pipes is the principal cause of "colored water" problems in drinking water distribution systems. The corrosion scales present in corroded iron pipes restrict the flow of water, and can also deteriorate the water quality. This research was focused on understanding the effect of dissolved oxygen (DO), a key water quality parameter, on iron release from the old corroded iron pipes. Corrosion scales from 70-year-old galvanized iron pipe were characterized as porous deposits of Fe(III) phases (goethite (alpha-FeOOH), magnetite (Fe(3)O(4)), and maghemite (alpha-Fe(2)O(3))) with a shell-like, dense layer near the top of the scales. High concentrations of readily soluble Fe(II) content was present inside the scales. Iron release from these corroded pipes was investigated for both flow and stagnant water conditions. Our studies confirmed that iron was released to bulk water primarily in the ferrous form. When DO was present in water, higher amounts of iron release was observed during stagnation in comparison to flowing water conditions. Additionally, it was found that increasing the DO concentration in water during stagnation reduced the amount of iron release. Our studies substantiate that increasing the concentration of oxidants in water and maintaining flowing conditions can reduce the amount of iron release from corroded iron pipes. Based on our studies, it is proposed that iron is released from corroded iron pipes by dissolution of corrosion scales, and that the microstructure and composition of corrosion scales are important parameters that can influence the amount of iron released from such systems.

... read more

Topics: Ferrous (59%), Magnetite (51%), Corrosion (50%) ... show more

274 Citations

No. of citations received by the Paper in previous years