• فهرس المقالات Decolorization

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        1 - Kinetic study on the electrodecolorization of C.I. Acid Yellow 23
        N. Modirshahla M.A. Behnajady S. Kooshaiian
        The electrocoagulation (EC) is a simple and efficient method for the treatment of many water and wastewaters.The kinetics of decolorization of Acid Yellow 23 by EC using iron electrodes was studied. Theelectrodecolorization rate follows pseudo-first order kinetic with r أکثر
        The electrocoagulation (EC) is a simple and efficient method for the treatment of many water and wastewaters.The kinetics of decolorization of Acid Yellow 23 by EC using iron electrodes was studied. Theelectrodecolorization rate follows pseudo-first order kinetic with respect to the AY23 concentration havingkapp= 5.65 cm min-1 at T= 295 K. The rate equation is as follows:ln [AY23]t ln [AY23]0 = -kapp2336 cm t250 cmThe pseudo-first order rate constant (kapp) is sensitive to the operational parameters. The kapp is low in bothhighly acidic and basic conditions. For the optimum operating conditions in electrodecolorization of AY23, theactivation energy was 41.15 kJ mol-1, sludge volume was about 8 ml from 250 ml of the original AY23 solution.The electrical energy consumption required for this treatment was 7.74 × 10-4 kW h and the electrodeconsumption was 37.4 mg. تفاصيل المقالة
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        2 - Sorption stuck). of C.I. Acid Red 88 from aqueous solutions onto sawdust
        N. Modirshahla M. A. Behnajady A. Shamel R. Eskandari
        The present study deals with the decolorization of CI Acid Red SR (ARAN as a model contaminant from textileindustry using sawdust as an adsorbent. The effects of initial AR88 concentration, adsorbent dosage, pH. c not acttime and ',riming rah: wcrg studied in a batch mo أکثر
        The present study deals with the decolorization of CI Acid Red SR (ARAN as a model contaminant from textileindustry using sawdust as an adsorbent. The effects of initial AR88 concentration, adsorbent dosage, pH. c not acttime and ',riming rah: wcrg studied in a batch mode. The variation of pH from 3 to 10 showed no considerablechange in decolorization rate. The desired conditions for decolorization or 84.46% were obtained to be 20 minof contact time, stirring rate of 400 rpm with 30 g L."' of adsorbent. Freundlich, Redlich-Peterson and Langmuiradsorption models were used for the mathematical description of the equilibrium data and the equilibriumprocess confirmed well with all the models attaining corn:611On Csaciduittnts 0.970, 0.96V and 0.958.respectively. The results also revealed that the adsorption kinetics obeys pseudo-second order and it wasconcluded that intra-particle diffusion model is not the rate determining step. تفاصيل المقالة
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        3 - The Kinetic and Thermodynamic Study for Decolorization of Congo red from Aqueous Solution Using Electrocoagulation Process
        Neamat Mohammadlou Mohammad Hasan Rasoulifard Motreaz Vahedpour Mohamad Reza Eskandarian
        The removal of color from synthetic wastewater containing Congo red was experimentally investigated using electrocoagulation process. The effects of operational parameters such as current density, electrolysis time, electrolyte concentration, electrode distance, initial أکثر
        The removal of color from synthetic wastewater containing Congo red was experimentally investigated using electrocoagulation process. The effects of operational parameters such as current density, electrolysis time, electrolyte concentration, electrode distance, initial dye concentration, initial pH and temperature on color removal efficiency were investigated in this study. The tentative results showed that Congo red in the aqueous phase was removed effectively by electrocagulation procedure. Optimum operating range for each of these operating variables was experimentally determined. Under the conditions of an initial dye concentration of 50mg/l, electrolysis time 5min, initial pH 7.5, current density 150A/ m2 , sodium chloride concentration 10g/l, interelectrode distance 0.5 cm, the color removal efficiency reached 98% when electrical energy consumption in this conditions for the decolorization of the dye solution containing Congo red was 0.46 KWh/m3 . Outcomes showed that the first-order rate equation could be described correlation for the decolorization rate of Congo red. The thermodynamic parameters, such as ∆Ho , ∆So and ∆Go , were also determined and evaluated. Further the experimental data were tested with different adsorption isotherm model to describe the electrocoagulation process. تفاصيل المقالة
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        4 - Amelioration of the acid blue oxidation process by as-synthesized ZnO nanoparticles: Optimization of the dye and photocatalyst concentration together with the pH of the solution
        Mehrnaz Gharagozloua Sanaz Naghibi Mohammad Ebrahim Olya
        In this research, ZnO nanoparticles (NPs) were synthesized using a binary Zn(II) Schiff-base complex. The complex heat-treated to prepare ZnO nanoparticles via thermal decomposition route at a temperature of 500 °C. The formation of single-phase ZnO nanoparticles an أکثر
        In this research, ZnO nanoparticles (NPs) were synthesized using a binary Zn(II) Schiff-base complex. The complex heat-treated to prepare ZnO nanoparticles via thermal decomposition route at a temperature of 500 °C. The formation of single-phase ZnO nanoparticles and their microstructures were studied by XRD pattern, SEM and TEM observation. The photo-degradation characteristic of the as-prepared ZnO NPs was evaluated and acid blue 193 was investigated as the organic colorant in a photocatalytic reactor by advanced oxidation process (AOP). The effects of operating parameters such as initial concentration of the dye, amount of catalyst and the pH value of the solutions were studied to determine the optimum condition of the process to improve the photo-degradation performance. According to the results, impressive photo-degradation of acid blue is conceivable by the as-synthesized ZnO NPs. The optimum operating conditions to achieve photo-degradation were found to be a solution with pH value of 6, the catalyst concentration of 0.04 g/L, and the dye concentration of 10 g/L. The highest efficiency would be achieved at natural pH of the solution (pH=~6). The optimum concentration of ZnO NPs is about 0.04 g/L. More or less amount of the photocatalyst could not enhance the photodegradation efficiency. At the constant photocatalyst concentration, any increase in dye amounts leads to decrease in degradation efficiency. تفاصيل المقالة
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        5 - Catalytic activity of immobilized Ag and Pd nanoparticles on the magnetic natural zeolite using Chrysanthemum morifolium flower extract in the reduction/decolorization of dyes
        Akbar Rostami-Vartooni Leila Rostami Mojtaba Bagherzadeh
        In this study, Ag and Pd nanoparticles (NPs) were immobilized on natural zeolite and magnetized zeolite (Fe3O4/natural zeolite) by using an aqueous Chrysanthemum morifolium flower extract, as a green and low-cost method. Different techniques such as FTIR, XRD, FESEM, ED أکثر
        In this study, Ag and Pd nanoparticles (NPs) were immobilized on natural zeolite and magnetized zeolite (Fe3O4/natural zeolite) by using an aqueous Chrysanthemum morifolium flower extract, as a green and low-cost method. Different techniques such as FTIR, XRD, FESEM, EDS, and VSM were used for the characterization of prepared nanocomposites. The FESEM and TEM images of nanocomposites showed that the quasi-spherical Ag and Pd NPs with mostly 20–50 nm particles size have successfully formed and are well dispersed on the supports surface. The effect of various parameters such as nanocomposite type, initial dye, NaBH4 concentrations, catalyst dose, and pH were studied in the catalytic reduction/decolorization of three organic dyes. In the absence of NaBH4 or catalyst, no color changes were observed even after 90 min. The reduction rates of the selected dyes in the presence of stable catalysts were found to be in an order of Pd/Fe3O4/natural zeolite > Pd/natural zeolite > Ag/Fe3O4/natural zeolite > Ag/natural zeolite > Fe3O4/natural zeolite. تفاصيل المقالة
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        6 - A comparison between the heterogeneous photodecolorization of an azo dye using Ni/P zeolite and NiS/P zeolite catalysts
        Alireza Nezamzadeh-Ejhieh Mahshid Khorsandi
        A comparison of the photoefficiency of Ni(II) and NiS incorporated into zeolite P towards photodecolorization of Eriochrome Black T dye solution was investigated in a photocatalytic reactor using UV lamp as a light source. The effect of various experimental variables on أکثر
        A comparison of the photoefficiency of Ni(II) and NiS incorporated into zeolite P towards photodecolorization of Eriochrome Black T dye solution was investigated in a photocatalytic reactor using UV lamp as a light source. The effect of various experimental variables on the decolorization performance of the process was evaluated by examining catalyst dosage, temperature, initial dye concentration and pH of the dye solution. The obtained results showed better efficiency of NiS/P than Ni/P catalyst. The decolorization process in both case obeyed first-order kinetics. تفاصيل المقالة
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        7 - Removal of Acid Red 33 from Aqueous Solution by Fenton and Photo Fenton Processes
        Aref Shokri
        In this project decolorization and mineralization of synthetic wastewater containing acid red 33 (AR33) was investigated by Fenton and photo Fenton processes in a batch photo reactor. A comparative assessment using Fenton and photo Fenton processes was performed after i أکثر
        In this project decolorization and mineralization of synthetic wastewater containing acid red 33 (AR33) was investigated by Fenton and photo Fenton processes in a batch photo reactor. A comparative assessment using Fenton and photo Fenton processes was performed after initial optimization studies such as varying pH, the concentration of pollutant, peroxide and iron. The color removal and mineralization efficiency of AR33 were calculated by Spectrophotometric and chemical oxygen demand (COD) tests. The degradation efficiency in photo Fenton process (98.5% in 10 min of reaction) was higher than Fenton ones (97.5% in 30 min). After 60 min of reaction, the removal of COD in photo Fenton and Fenton processes was 71% and 37.5%, respectively. Therefore, photo Fenton was the most effective process in partial mineralization of AR33. Kinetic constants were evaluated using pseudo first order equations to obtain the rate constant, K. تفاصيل المقالة
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        8 - Insight into the Oxidant Agents Effect of Removal and Photo-decolorization of Vitamin B12 Solution in Drug Tablets using ZrO2
        Shaymaa Ibrahim Saeed Ban Hasan Taresh Luma M. Ahmed Zainab Faisal Haboob Safa Alaa Hassan Athraa Abd Al-amir Jassim
        The purpose of this manuscript was to remove and decolorize vitamin B12 from an aqueous solution of drug tablets using ZrO2 as an environmentally friendly method via advanced oxidation processes. Some oxidant agents such as Fe2+, H2O2, K2S2O8 and their mixture of were p أکثر
        The purpose of this manuscript was to remove and decolorize vitamin B12 from an aqueous solution of drug tablets using ZrO2 as an environmentally friendly method via advanced oxidation processes. Some oxidant agents such as Fe2+, H2O2, K2S2O8 and their mixture of were performed, and the best adsorption sequences have occurred with increased adsorption capacity: q(K2S2O8 + H2O2)>q(H2O2) >q (K2S2O8) >q (Fe2+ + H2O2) >q (Fe2+)>q (without) Endothermic and physical adsorption occurred of this vitamin on the ZrO2 surface with and without the addition of K2S2O8 +H2O2. On the other side, the photoreaction for this vitamin with and without the addition of K2S2O8 +H2O2 was found to be quick, endothermic, less random, and spontaneous. At 15 min, 33.223 % and 98. 684% were calculated as the maximum percentage of removal in the dark reaction and the maximum decolorization in the photocatalytic reaction respectively. تفاصيل المقالة