scholarly journals The Efficiency of Separate and Combined Modified Electrolysis Processes and Electric Coagulation in Removing Yellow Gold Dye (Gold Yellow X-GL) from Aqueous Solutions

2019 ◽  
Author(s):  
Reza Ali Fallahzadeh ◽  
Davoud Ghadirian ◽  
Ahmad Fattahi ◽  
Pejman Amjadian ◽  
Samaneh Mozaffary ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Dye Removal ◽  
Refining Process ◽  
Process Efficiency ◽  
Iron Electrode ◽  
Optimal Conditions ◽  
Yellow Color ◽  
Golden Yellow ◽  
The Impact

Introduction: Disposal of the wastewater produced in the paper and paperboard industry without the refining process can add substances to the environment, which are harmful to humans, environment, and other organisms. With regard to process efficiency, the current methods used in wastewater treatment of this industry are economically unjustifiable. Therefore, in this research, the electrolysis / electrocoagulation method was investigated using a graphite / iron electrode for synthetic aqueous solutions containing golden yellow X-GL. Materials and Methods: In this test, two Plexiglas reactors with a volume of 3 liters were used. The impact of the operation parameters such as voltage, initial dye concentration, and reaction time were investigated. Dye concentration in specimens was determined by visible spectrophotometry using DR-5000 at 438nm wavelength. Results: In optimal conditions of voltage 12V, dye concentration 10 mg/l, and time 60 min, the removal efficiency rates of electrolysis reactors, electric coagulation, and combined reactor were 64.17%, 75.42%, and 84.19% respectively. By increasing the dye concentration and decreasing the voltage, the dye removal efficiency decreased. Conclusion: The electric coagulation process using an iron electrode is a suitable method for removing the yellow color of colored aqueous solutions from the paper and paperboard industry.

Degradation of basic violet 16 dye by electro-activated persulfate process from aqueous solutions and toxicity assessment using microorganisms: determination of by-products, reaction kinetic and optimization using Box–Behnken design

2021 ◽  
Vol 19 (3) ◽  
pp. 261-275
Author(s):  
Kamal Hasani ◽  
Mina Moradi ◽  
Seiyed Ahmad Mokhtari ◽  
Hadi sadeghi ◽  
Abdollah Dargahi ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Dye Removal ◽  
Electrical Energy ◽  
Electrolysis Time ◽  
Optimal Conditions ◽  
Box Behnken Design ◽  
First Order ◽  
Pseudo First Order ◽  
By Products

Abstract This study was performed to determine the efficiency of the electro/persulfate process to remove basic violet 16 (BV16) dye and COD from aqueous solutions. The present study was experimentally performed on a laboratory scale. The effect of pH on the process was investigated independently, and after performing the experiments, the effect of voltage (volts), the dose of persulfate (g/L), initial concentration of BV16 dye, and electrolysis time was investigated with the model presented by Box Behnken design, and optimal conditions for BV16 dye removal was obtained. Under optimal conditions, COD removal efficiency and toxicity changes during the process were calculated, and the effect of distance between electrodes and surface of electrodes on process efficiency was investigated. By-products of oxidative degradation were determined with LS-MS. The amount of electrical energy consumed by the process was investigated by voltage changes and then the kinetics of the process was investigated by a pseudo-first-order model. The results showed that the electro/persulfate process in optimal conditions including pH of 5, a voltage of 11.43 V, persulfate dose of 0.09 g/L, initial BV16 concentration of 45 mg/L, and electrolysis time of 48.5 min could provide BV16 dye removal efficiency of 95% and COD removal efficiency of 57.14%. Findings of electrical energy consumption showed that with increasing voltage, the efficiency of the process increased, but the amount of energy consumption also increased. Under optimal conditions, increasing distance between the electrodes was led to a decrease in removal efficiency, but the removal efficiency increased with the increasing surface of the electrodes. Based on the kinetic results, the electro/persulfate process followed pseudo-first-order kinetics with R 2 = 0.9956. The present study showed that the electro/persulfate process as a useful technique has high efficiency in removing BV16 dye and its toxicity from aqueous solutions and can be effective and useful in removing the COD of solution.

Study of the Removal of Boron from Metallurgical Grade Silicon by Oxidation Slagging Method

2010 ◽  
Vol 156-157 ◽  
pp. 882-885 ◽  
Author(s):  
Yu Yan Hu ◽  
Dong Liang Lu ◽  
Tao Lin ◽  
Yu Liu ◽  
Bo Wang ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Orthogonal Experiment ◽  
Slag System ◽  
Refining Process ◽  
Impact Factors ◽  
Metallurgical Grade Silicon ◽  
Optimum Parameters ◽  
Grade Silicon ◽  
Refining Time ◽  
The Impact

Refining of solar grade silicon by metallurgical method is the research hotspot of polycrystalline field. Slagging method is benefit to the removal of the impurities especially to boron exsisted in the raw silicon. In this study, the influence of the density, the viscosity and liquidus temperature of the slag components on the refining process were discussed, and then the slag system SiO2-Na2CO3 was choosed as the slagging agents. And then the impact factors on the removal efficiency of boron such as the composition of SiO2 and Na2CO3, the ratio of slag to silicon and the refining time were investigated by the orthogonal experiment. The results showed that the optimum parameters of the oxidation refining for removing boron were as follows: the main composition of the oxidant is “SiO2 : Na2CO3 = 60% : 40%”; the slag/silicon ratio is 0.5; time for refining is 60min at 1550 . The results indicated that the removal efficiency of boron was 88.28%, and the content of boron in MG-Si can be reduced to 7ppmw under the best refining process¬.

scholarly journals Effect of Praestol as a Coagulant-Aid to Improve Coagulation-Flocculation in Dye containing Wastewaters

2015 ◽  
Vol 18 (1) ◽  
pp. 38-46 ◽  
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Dye Removal ◽  
Settling Time ◽  
Solution Ph ◽  
Polyaluminum Chloride ◽  
Flocculation Process ◽  
Flocculation Time

<div> <p>This study was conducted to investigate the effect of praestol, as a coagulant-aid, to improve coagulation-flocculation process in the removal of disperse red 60 from aqueous solutions. The effect of various parameters including coagulants dose (10-1000 mg l<sup>-1</sup>), praestol dose (0-1000 mg l<sup>-1</sup>), solution pH (3-11), initial dye concentration (100-500 mg l<sup>-1</sup>), flocculation speed (30-60 rpm), flocculation time (15-30 min), settling time (5-60 min) and ionic strength (0-6 mg l<sup>-1</sup>) was evaluated on the dye removal. The dye removal efficiency was substantially increased by using praestol in the concentration of 80 mg l<sup>-1 </sup>and 400 mg l<sup>-1 </sup>for coagulation with alum and polyaluminum chloride (PACl), respectively. The maximum dye removal by alum coupled with praestol (Al-P) and PACl coupled with praestol (PA-P) was found to be 97.8% and 98.7%, respectively that were occurred at pH 7. The results showed that the application of PA-P or Al-P can be effectively used to remove disperse red 60 (DR 60) in aqueous solutions.</p> </div> <p>&nbsp;</p>

scholarly journals Removal of Cr(VI) from Aqueous Environments Using Micelle-Clay Adsorption

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Mohannad Qurie ◽  
Mustafa Khamis ◽  
Adnan Manassra ◽  
Ibrahim Ayyad ◽  
Shlomo Nir ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Continuous Flow ◽  
Contact Time ◽  
Langmuir Adsorption Isotherm ◽  
Optimal Conditions ◽  
Batch Experiments ◽  
Langmuir Adsorption ◽  
Ph Values ◽  
Aqueous Environments

Removal of Cr(VI) from aqueous solutions under different conditions was investigated using either clay (montmorillonite) or micelle-clay complex, the last obtained by adsorbing critical micelle concentration of octadecyltrimethylammonium ions onto montmorillonite. Batch experiments showed the effects of contact time, adsorbent dosage, and pH on the removal efficiency of Cr(VI) from aqueous solutions. Langmuir adsorption isotherm fitted the experimental data giving significant results. Filtration experiments using columns filled with micelle-clay complex mixed with sand were performed to assess Cr(VI) removal efficiency under continuous flow at different pH values. The micelle-clay complex used in this study was capable of removing Cr(VI) from aqueous solutions without any prior acidification of the sample. Results demonstrated that the removal effectiveness reached nearly 100% when using optimal conditions for both batch and continuous flow techniques.

scholarly journals Study of the effectiveness of the third generation polyamideamine and polypropylene imine dendrimers in removal of reactive blue 19 dye from aqueous solutions

2018 ◽  
Vol 5 (4) ◽  
pp. 197-203 ◽  
Author(s):  
Sepideh Sadeghi ◽  
Ghazal Raki ◽  
Asrin Amini ◽  
Nezamaddin Mengelizadeh ◽  
Mohammad Mehdi Amin ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Dye Removal ◽  
Synthetic Wastewater ◽  
Third Generation ◽  
Freundlich Isotherms ◽  
The Third ◽  
Reactive Blue 19 ◽  
Adsorption Data ◽  
Poly Propylene

Background: Dye and colored materials cause health risks in water and therefore, must be removed from water supplies and wastewater. The aim of this study was to evaluate the effectiveness of the third generation poly(amidoamine) (PAMAM) and poly (propylene imine) dendrimers (PPI-G3) in the removal of reactive blue 19 (RB19) dye from aqueous solutions and determine the optimum conditions for the removal. Methods: This study was performed in a laboratory and batch scale. In this study, synthetic wastewater was examined with three different concentrations of RB19 (25, 50, and 100 mg/L), different pHs (3, 7, and 10), various amounts of dendrimer (0.4, 0.8, 1.2, and 1.6 g/L), and at different times (15, 30, and 60 minutes) during the adsorption process. The remaining amount of dye was measured by spectrophotometer at 592 nm wavelength. Langmuir and Freundlich isotherms were also tested. Results: The results showed that by increasing the reaction time and adsorbent dosage, the rate of dye removal increased while by increasing the initial dye concentration and pH, the dye removal efficiency was significantly decreased. In this study, with increase of pH from 3 to 10, dye removal efficiency at a concentration of 25 mg/L, decreased from 72% to 20% and 88% to 17% by PAMAM and PPI dendrimers, respectively. Excel software was used for data analysis. Conclusion: Both adsorbents had a good dye removal efficiency, but PPI dendrimer was more effective in removing RB19. Adsorption data followed the Langmuir isotherm.

scholarly journals Arsenic removal by the micellar-enhanced ultrafiltration using response surface methodology

2019 ◽  
Vol 20 (2) ◽  
pp. 574-585 ◽  
Author(s):  
Oznur Begum Gokcek ◽  
Nigmet Uzal
Keyword(s):  
Response Surface Methodology ◽  
Aqueous Solutions ◽  
Response Surface ◽  
Removal Efficiency ◽  
Surfactant Concentration ◽  
Arsenic Removal ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Micellar Enhanced Ultrafiltration ◽  
The Impact

Abstract The present research investigates the removal of arsenic (As) from aqueous solutions using micellar-enhanced ultrafiltration (MEUF) by utilizing two different surfactants: benzethonium chloride and dodecyl pyridinium chloride (BCl and DPCl). The impact of the operating variables and maximum removal efficiency were found under different conditions for BCl and DPCl surfactants. The maximum As rejection efficiency for MEUF with BCl and DPCl surfactants is 92.8% and 84.1%, respectively. In addition to this, a statistics-based experimental design with response surface methodology was used for the purpose of examining the impact of operating conditions, including initial pH, initial As concentration (ppb), and surfactant concentration (BCl, mM) in As-removal from aqueous solutions. In the analysis of the experimental data, a second-order polynomial model that was validated by statistical analysis for the BCl surfactant was used. On the basis of the response model created, the removal of As ions was acquired at optimum operating parameters, including the initial As concentration of 150 ppb, surfactant concentration of 5 mM and pH 10 for the BCl surfactant with 92.8% As-removal efficiency.

scholarly journals Electrocoagulation of textile wastewater containing a mixture of organic dyes by iron electrode

2017 ◽  
Vol 7 (2) ◽  
pp. 103 ◽  
Author(s):  
Borislav N. Malinović ◽  
Miomir G. Pavlović ◽  
Tijana Djuričić
Keyword(s):  
Removal Efficiency ◽  
Organic Dyes ◽  
Supporting Electrolyte ◽  
Specific Energy Consumption ◽  
Oxygen Demand ◽  
Color Removal ◽  
Iron Electrode ◽  
Synthetic Wastewater ◽  
Initial Concentration ◽  
The Impact

This study focused on testing the efficacy of iron (Fe) electrode in an electrochemical treatment (electrocoagulation) of wastewater containing a mixture of organic dyes. The mixture consists of the following azo dyes: Acid Black 194, Acid Black 107 and Acid Yellow 116. The present organic dyes are toxic, cause skin and eye irritation and are extremely dangerous to aquatic organisms. The study was conducted on a synthetic wastewater prepared in a laboratory electrochemical reactor. During the research, the impact of the current density, various concentrations of dye and supporting electrolyte, electrolysis duration and <em>pulsed current regime </em><em>were tracked</em>. The results are shown through color removal efficiency, chemical oxygen demand (COD) removal efficiency, current efficiency, and specific energy consumption. At the initial concentration of dye (γ=200 mg/L) and concentration of supporting electrolyte (γ<sub>NaCl</sub>=1 g/L) the color removal efficiency of 80.64% was achieved for 420 seconds of treatment (ј=10 mA/cm<sup>2</sup>). At the initial concentration of dye (γ=50 mg/L) and γ<sub>NaCl</sub>= 8 g/L, the color removal efficiency of 96.01% was attained for 300 seconds of treatment (ј=10 mA/cm<sup>2</sup>)

scholarly journals De-Colourisation of Textile Dye Effluents using cost-effective Nigella Sativa Seed Waste

2020 ◽  
Vol 06 (9S) ◽  
pp. 78-82
Author(s):  
Raja Balasaraswathi S and Kiruba T
Keyword(s):  
Removal Efficiency ◽  
Dye Removal ◽  
Nigella Sativa ◽  
Effluent Treatment ◽  
Textile Dye ◽  
Active Components ◽  
Experimental Conditions ◽  
Black Cumin ◽  
The Impact ◽  
Nigella Sativa Seed

The textile industry is one of the major industries contributing to water pollution. The wet processing of textiles involves the usage of a wide variety of chemicals and dyes. This water-intensive process can potentially affect the water bodies by its effluents. The treatment of dye effluents and reusing of the water could be the possible solution to reduce the impact. Adsorption is one of the most common methods used for textile effluent treatment. Various bio-adsorbents are explored to make the adsorption more sustainable. Nigella Sativa (Black cumin) seeds and its oil are having good medicinal value. The seed-waste left after the oil extraction is found to have active components that can be used as an effective bio-adsorbent. The dye removal efficiency of Nigella Sativa seed-waste is investigated under different experimental conditions (varied adsorbent dose, temperature, pH, and contact time) for reactive dyes. The maximum removal efficiency of 91% is obtained at the optimized experimental condition. Thus the study emphasizes that the no-cost Nigella Sativa seed-waste can be used as an effective bio-adsorbent for reactive dye removal from dye effluents.

Optimization of copper removal from aqueous solutions in a continuous electrochemical cell divided by cellulosic separator

2016 ◽  
Vol 75 (5) ◽  
pp. 1233-1242 ◽  
Author(s):  
Ali Asghar Najafpoor ◽  
Mojtaba Davoudi ◽  
Elham Rahmanpour Salmani
Keyword(s):  
Energy Consumption ◽  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Copper Concentration ◽  
Electrochemical Cell ◽  
Current Intensity ◽  
Copper Removal ◽  
Flow Mode ◽  
Electrolysis Time ◽  
Optimal Conditions

Copper, as an inseparable part of many industrial discharges, threatens both public and environmental health. In this work, an electrochemical cell utilizing a cellulosic separator was used to evaluate Cu removal using graphite anodes and stainless steel cathodes in a continuous-flow mode reactor. In the experimental matrix, Cu concentration (1–5 mg L−1), electrolysis time (20–90 min), and current intensity (0.1–0.4 A) were employed. Results showed that the maximum removal efficiency of copper was obtained as 99%. The removal efficiency was independent of initial copper concentration and directly related to electrolysis time and current intensity. Energy consumption was more dependent on current intensity than electrolysis time. Under optimal conditions (75.8 min electrolysis time, 0.18 A current intensity, and 3 mg L−1 copper concentration), the removal efficiency was obtained as 91% while 7.05 kWh m−3 electrical energy was consumed. The differences between the actual and predicted data under optimal conditions were 0.42% for copper removal and 0.23% for energy consumption, which signify the performance and reliability of the developed models. The results exhibited the suitability of the electrochemical reduction for copper removal from aqueous solutions, which was facilitated under alkaline conditions prevailing in the cathodic compartment due to applying a cell divided by a cellulosic separator.

scholarly journals Iron Molybdate Fe2(MoO4)3 Nanoparticles: Efficient Sorbent for Methylene Blue Dye Removal from Aqueous Solutions

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5100
Author(s):  
Ahmed Mohmoud ◽  
Souad Rakass ◽  
Hicham Oudghiri Hassani ◽  
Fethi Kooli ◽  
Mostafa Abboudi ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Aqueous Solutions ◽  
Removal Efficiency ◽  
Dye Removal ◽  
Blue Dye ◽  
Iron Molybdate ◽  
Thermal Regeneration ◽  
Simple Method ◽  
Removal Capacity ◽  
Adsorbent Dose

The present study investigated iron molybdate (Fe2(MoO4)3), synthesized via a simple method, as a nanosorbent for methylene blue (MB) dye removal from aqueous solutions. Investigations of the effects of several parameters like contact time, adsorbent dose, initial dye concentration, temperature and pH were carried out. The results showed that MB removal was affected, significantly, by adsorbent dose and pH. Interestingly, lower values of adsorbent dose resulted in the removal of higher amounts of MB. At the optimum pH, the removal efficiency of 99% was gained with an initial MB concentration of ≤60 ppm. The kinetic study specified an excellent correlation of the experimental results with the pseudo-second-order kinetics model. Thermodynamic studies proved a spontaneous, favorable and endothermic removal. The maximum amount of removal capacity of MB dye was 6173 mg/g, which was determined from the Langmuir model. The removal efficiency was shown to be retained after three cycles of reuse, as proven by thermal regeneration tests. The presence and adsorption of the dye onto the Fe2(MoO4)3 nanoparticle surface, as well as the regeneration of the latter, was ascertained by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). These findings are indicative that the investigated nanosorbent is an excellent candidate for the removal of MB in wastewater.

Sign in / Sign up

Export Citation Format

Share Document