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•A magnetic pine cone gel beads (MPCB) based adsorbent was successfully prepared.•Single and binary adsorption systems of Cu(II) and Cr(VI) were investigated.•High adsorption capacity ...of 69.8 mg.g−1 for Cu(II) and 132.5 mg.g−1 for Cr(VI).•Modeling of isotherms by statistical physics and competitive Langmuir model.•Adsorption mechanism of Cr(VI) and Cu(II) onto MPCB was elucidated.
Recently, the use of magnetic sorbents has gained a spread attention due to their eco-friendly characteristic, ease of separation and low cost. Herein, a novel biocomposite sorbent magnetic pine cone gel beads (MPCB) was synthetized and investigated for the single and the simultaneous removal of Cu(II) and Cr(VI) from aqueous solution. Pine cones waste materials were first magnetized with Fe3O4 nanoparticles then were encapsulated in calcium gel beads. The physicochemical properties of the prepared MPCB were characterized via scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction and Fourier transform infrared spectrometry (FTIR) analysis. The influences of pH, contact time and initial concentration of metal ions on the sorption process were examined. The adsorption mechanism was investigated; it mainly involved complexation/chelation with surface functional groups, electrostatic interaction and ion exchange. A physical model was adopted to attribute new physico-chemical interpretations of the adsorption mechanism. The kinetic results showed good correlation with pseudo second-order model and the equilibrium data were fitted well to the Langmuir isotherm model with maximum adsorption capacity of 68.64 and 212.22 mg g−1 for Cu(II) and Cr(VI) respectively. In the multi-components system, both competitive and synergistic effects were observed. An antagonism effect was exerted by Cu(II) ions on Cr(VI) sorption while Cu(II) adsorption was not affected and even slightly enhanced by the presence of Cr(V) ions. The competitive sorption behavior of metal ions was analyzed by the modified competitive Langmuir model which provides good fit for the Cu experimental data. This study proves that the MPCB hold great promise for using as effective sorbent for potentially toxic metals remediation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The removal of heavy metals in an aquatic environment is a crucial problem because the pollution by heavy metals is common in water systems. In this study, a low-cost activated carbon from the waste ...of date palm fiber (AC-DPF) was prepared for the potential adsorption of lead and copper from simple and binary systems. The surface area of AC-DPF was 1603.496 m2/g. The effect of factors influencing the adsorption of Pb(II) and Cu(II) by AC-DPF were discussed. The maximum adsorption efficiencies were 92 % and 80 % for Pb(II) and Cu(II), respectively. Furthermore, the AC-DPF adsorption was investigated kinetically and thermodynamically. A good fit of equilibrium results to the Langmuir model was achieved with a maximum adsorption capacity of 29.859 mg/g for Pb (II) and 25.048 mg/g for Cu(II). Competitive and antagonistic effects were observed in the multi-component system. Based on the results, AC-DPF was a highly promising, effective and feasible adsorbent for heavy metal removal potential.
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•A low-cost activated carbon from date palm fiber (AC-DPF) is prepared by chemical activation with ZnCl2.•AC-DPF exhibited a large surface area.•The adsorption of lead and copper was studied.•Adsorption mechanisms were found to be both surface complexation and electrostatic attraction.•AC-DPF is a renewable adsorbent that is useful for the removal of toxic pollutants.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Fluoride forms a common aqueous effluent in many chemical industries. Excess of fluoride in the effluent can cause a health hazard. So, effluent containing fluoride needs treatment to reduce its ...concentration to a disposable value before discharging into public sewage. Removal of fluoride ion from model water solutions was investigated using polyamide thin film composite reverse osmosis and nanofiltration membranes. The effects of feed pressure, concentration, ionic strength, nature of cation associated to fluoride, and pH on the retention of fluoride ions were studied. Membranes were used to reduce fluoride ions and total salinity of a metal packaging industrial effluent. The retention of fluoride exceeds 90% for both membranes. This was found to depend on feed concentration, ionic strength, pH, and applied pressure. The Spiegler-Kedem model was applied to experimental results to determine phenomenological parameters σ and P
s
, the reflection coefficient of the membrane and the solute permeability coefficient of ions. The convective and diffusive parts of the mass transfer were quantified with predominance of the diffusive contribution.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
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•Tamisolve® was used as a non-toxic solvent for P(VDF-HFP) membranes preparation.•The prepared porous P(VDF-HFP) membranes were fully characterized.•The membranes were tested in ...membrane distillation and membrane crystallization.•Membrane crystallization allowed achieving crystals with rejection greater than 99%.
The replacement of the toxic solvents with non-toxic equivalents attracts a great attention in membrane preparation and application processes. The purpose of this work is to study the preparation of poly(vinylidene fluoride-hexafluoropropylene) P(VDF-HFP) flat sheet membranes by non-solvent induced phase separation (NIPS) using Tamisolve® as a non-toxic solvent, for membrane distillation (MD) and membrane crystallization (MCr) applications. The prepared porous P(VDF-HFP) membranes were fully characterized in terms of morphology, porosity, thickness, pore-size, contact angle and pure water permeability (PWP). The effect of additive(s) and polymer content were investigated. Moreover, preliminary DCMD and MCr tests were carried out and the achieved results indicate the good performance of the prepared flat sheet membranes in terms of permeate flux and salt rejection in comparison to a commercial PVDF membrane. The obtained results confirmed the ability of the eco-friendly Tamisolve® NxG to compete with the highly toxic diluents usually used in membrane fabrication by phase inversion method.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Industrial effluents loaded with cadmium have contributed to the pollution of the environment and health troubles for humans. Therefore, these effluents need treatment to reduce cadmium concentration ...before releasing them to public sewage. The purpose of the research is to study the major role of reverse osmosis (RO) and nanofiltration (NF) processes, which can contribute to the removal of cadmium ions from model water and wastewater from the battery industry. For this reason, two RO and two nanofiltration membranes have been used. The effects of feed pressure, concentration, ionic strength, nature of anion associated with cadmium and pH on the retention of Cd(II) were studied with model solutions. Thereafter, NF and RO membranes were used to reduce cadmium ions and total salinity of battery industry effluent. Among these membranes, there are only three which eliminate more than 95% of cadmium. This was found to depend on operating conditions. It is worth noting that the Spiegler-Kedem model was applied to fit the experimental results.
Boron removal from water containing 5 mg L
of boron using electrodialysis (ED) was studied as a function of several parameters such as flow rates, initial pH, coexisting anions and ED time. An ED ...cell, equipped with three cation exchange membranes (fumasep FKB) and two anion exchange membranes (fumasep FAB), was applied. The central composite design, which is the standard design of response surface methodology, was used to evaluate the effects and interactions of studied factors on boron removal efficiency. The effectiveness of the considered design parameters was well examined to find the optimum condition. The experimental data obtained were analyzed by analysis of variance for the polynomial model with 95% confidence level. Boron removal by ED showed to be independent of the electrodialysis time, whereas flow rate as well as the pH of the feed solution and also the coexisting anions on the feed solution play a significant role on the deboronation efficiency. According to the desirability function, the maximum response of 43.5% was predicted for boron removal at a pH equal to 10, a flow rate of 10 L h
, a ratio between sulfates and that of boron equal to 2 and a reaction time of 25 minutes.
This study reported the use of olive leaves Chemlali pruning waste (OLC) as biosorbent for Cr(VI) ions removal from aqueous solution via a batch process. An ideal experimental model was applied using ...central composite design (CCD) based on response surface methodology (RSM) to find the best operating conditions. The optimum removal efficiency of Cr(VI) onto OLC was ascertained as 99.98% at 3.9 initial solution pH, 0.73 g adsorbent mass, and 37.25 °C temperature for 100 mg/L initial Cr(VI) concentration. Analysis of variance (ANOVA) showing a high coefficient of determination (
R
2
= 0.999) and low probability values signified the validity of the predicted model. Results showed that the CCD was an effective tool for enhancing the adsorption procedure. Several adsorption models were used to study the investigative data as well. The experimental data best fitted with Langmuir isotherm with maximum Cr(VI) biosorption capacities equaling to 21.157, 22.634, 30.672, and 40.312 mg/g at 283, 298, 308, and 318 K, respectively. The removal of Cr(VI) onto OLC followed pseudo-second-order kinetics. The thermodynamic studies indicated a spontaneous and endothermic process. The OLC was characterized using different physicochemical methods. The FTIR revealed the interaction of some functional groups in the adsorption of chromium ions, including carboxylic acid, hydroxyl, and amide. The OLC adsorbent was regenerated with NaOH, NaCl solution, and distilled water until five recycle runs for further reuse. Overall, results showed that OLC is an effective and economical alternative with great potential for hexavalent chromium recovery.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The occurrence of boron in water and its inefficient removal are the key issue in desalination and water treatment. Adsorption by fixed-bed column is usually used to remove mineral and organic ...contaminants from the aqueous phase. The adsorption of the boron onto activated carbon, prepared from palm bark, is studied. Batch adsorption experiments are developed to determine the equilibrium time and the best isotherm model. The kinetic adsorption data can be described by the second-order equation. Among the adsorption isotherm models, Langmuir and Sips models give better fit of the equilibrium data. The calculated thermodynamic parameters show that the boron adsorption is exothermic in nature. The effects of inlet boron concentration, feed flow rate and weight of activated carbon on the fixed-bed adsorption are determined by two-level factorial experimental design. Breakthrough and saturation times are higher at high adsorbent weight and low flow rates. The increase of boron initial concentration decreases breakthrough and saturation times. The volume treated per gram of activated carbon is higher at lower initial concentrations and at higher adsorbent weight. Compared to other models, the Yan model fits better the experimental data of the breakthrough curves with R
of 0.993.
The results of this work showed that UV/IO3− oxidation process supplies good performance in the degradation of light green SF yellowish (LGSFY) dye in deionized water. This process generated reactive ...iodine radicals that make the degradation much faster than the sole UV irradiation. The assistance of UV-irradiation by 10 mM of iodate increased the LGSFY removal after 10 min from 36% to 90% for C0 = 10 mg/L and from 18% to 85% for C0 = 20 mg/L. In parallel, a 2.5 and 4.72-fold increase in the LGSFY initial degradation rate, as compared with UV alone, were recorded for, respectively, 10 and 20 mg/L of LGSFY. IO2 and IO played the most important role in the degradation of LGSFY by the UV/IO3− process. The degradation was not affected by the presence of chloride and nitrate ions even at high dosage levels (up to 0.1 M), whereas sulfate ions reduced the valuable effect of iodate to the half when they are present at 0.1 M. Correspondingly, humic acids, at usual concentrations as those measured in natural waters, did not affect significantly the LGSFY degradation upon photoactivated iodate process. These results revealed, in one part, that iodine radicals are selective oxidants and, in another part, that the process is likely to remove organic dyes from natural water which often contains mineral constitutes and humic substances.
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•Iodate-assisted UV-light accelerated drastically the removal of LGSFY dye in water.•The iodate-enhanced effect was more pronounced at higher LGSFY initial concentration.•IO2 and IO played the key role in the degradation of LGSFY by UV/IO3− process.•UV/IO3− process is likely to remove organic dyes from real environmental waters.•UV/IO3− process is an alternative to UV/IO4− process for wastewaters treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Date Palm Fiber was used as a renewable and low-cost precursor for the activated carbon.•The operating conditions were successfully optimized from RSM.•The optimized activated carbon OAC exhibited a ...large surface area and a high yield.•OAC presented a maximum adsorption capacity of 147.05 mg g−1 for Tylosin.•OAC was regenerated up to 8 cycles.
This paper aims to produce a low-cost activated carbon based on the precursor material Date Palm Fiber by chemical activation with ZnCl2. The preparation conditions, including the activation temperature, activation time and impregnation ratio (IR) were optimized by the rotatable central composite design of response surface methodology (RSM) to maximize the surface area and the yield. Therefore, the optimal conditions values were determined as 432°C for the activation temperature, 10 min for the activation time and 1.42 for the IR to produce an activated carbon with a high surface area and yield of 1726.11 m2/g and 54.3%, respectively. The optimized activated carbon (OAC) was characterized by CHNS-O analysis, Brunauer-Emmett-Teller (BET) isotherms, Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). Furthermore, equilibrium, kinetic and thermodynamic studies have been conducted to evaluate the derived activated carbon's performance at optimized Tylosin (TYL) removal conditions. The adsorption mechanism was elucidated. The high removal efficiency of TYL (99%) was obtained at pH 5.5 and ambient temperature. Langmuir isotherm and the pseudo-second-order model fit well the experimental data with a maximum adsorption capacity of 147 mg/g. The reusability up to eight adsorption-desorption cycles was tested. Experimental results indicate that OAC can be used as a potential sorbent for the organic pollutant removal from wastewaters.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP