scholarly journals RESEARCH ON ELECTROCHEMICAL METHODS TO REMOVE FLUORIDE FROM WATER

2017 ◽  
Vol 126 (1C) ◽  
pp. 85
Author(s):  
Võ Anh Khuê
Keyword(s):  
Optimal Condition ◽  
Removal Efficiency ◽  
Water Solution ◽  
Electrochemical Methods ◽  
Fluoride Ion ◽  
Residual Concentration ◽  
Initial Concentration ◽  
Iron Electrodes ◽  
Aluminum Electrodes

<p>The use of electrochemical methods such as micro-electrolysis, electrocoagulation, and micro-electrolysis combined with electrocoagulation to remove fluoride from water were studied in this paper. The results indicated that the micro-electrolysis (using Fe/C particles) and the electrocoagulation (using iron electrodes) are not suitable for removal of fluoride from water solution. The electrocoagulation method with aluminum electrodes for removal efficiency of fluoride is very good. But it is not as good as the micro-electrolysis (using Fe/C particles) combined with the electrocoagulation method (using aluminum electrodes). At the optimal condition of the micro-electrolysis (using Fe/C particles) combined with the electrocoagulation method (using aluminum electrodes) and the initial concentration of fluoride ion of 50 mg/L, the removal efficiency of fluoride ion is 94.03% and the residual concentration is 2.986 mg/L.</p>

RESEARCH ON ELECTROCHEMICAL METHODS TO REMOVE FLUORIDE FROM WATER

2017 ◽  
Vol 126 (2B) ◽  
Author(s):  
Võ Anh Khuê
Keyword(s):  
Optimal Condition ◽  
Removal Efficiency ◽  
Water Solution ◽  
Electrochemical Methods ◽  
Fluoride Ion ◽  
Residual Concentration ◽  
Initial Concentration ◽  
Iron Electrodes ◽  
Aluminum Electrodes

<p>The use of electrochemical methods such as micro-electrolysis, electrocoagulation, and micro-electrolysis combined with electrocoagulation to remove fluoride from water were studied in this paper. The results indicated that the micro-electrolysis (using Fe/C particles) and the electrocoagulation (using iron electrodes) are not suitable for removal of fluoride from water solution. The electrocoagulation method with aluminum electrodes for removal efficiency of fluoride is very good. But it is not as good as the micro-electrolysis (using Fe/C particles) combined with the electrocoagulation method (using aluminum electrodes). At the optimal condition of the micro-electrolysis (using Fe/C particles) combined with the electrocoagulation method (using aluminum electrodes) and the initial concentration of fluoride ion of 50 mg/L, the removal efficiency of fluoride ion is 94.03% and the residual concentration is 2.986 mg/L.</p>

scholarly journals Efficient removal of arsenic from water by dielectrophoresis-assisted adsorption

2018 ◽  
Vol 19 (4) ◽  
pp. 1066-1072
Author(s):  
Q. H. Jin ◽  
C. Y. Cui ◽  
H. Y. Chen ◽  
Y. Wang ◽  
J. F. Geng ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Removal Efficiency ◽  
Solution Ph ◽  
Residual Concentration ◽  
Initial Concentration ◽  
Weight Percentage ◽  
Before And After ◽  
High Concentrations ◽  
Plant Ash ◽  
Adsorbent Dose

Abstract Adsorption (ADS) and dielectrophoresis (DEP) techniques were combined (ADS/DEP) to efficiently remove As(V) in industrial wastewater. Fly ash, activated carbon, corncob and plant ash were tested to determine the best adsorbent by their adsorption capacity. Plant ash showed the highest adsorption capacity compared with the others. Different parameters such as solution pH and adsorbent dose were explored. The maximum As(V) removal efficiency was 91.4% at the optimized conditions (pH 9.0, adsorbent dose 5 g/L) when the initial concentration of As(V) was 15 mg/L. With the ADS/DEP technique, the plant ash particles with adsorbed As(V) were trapped on the electrodes in a DEP device. The ADS/DEP process could increase the removal efficiency of As(V) to 94.7% at 14 V even when the initial concentration of As(V) was 15 mg/L. And the residual concentration of As(V) decreased to 0.34 mg/L after two series of the ADS/DEP process. The adsorbents before and after DEP were examined by scanning electron microscope (SEM) and energy dispersive X-ray (EDX) analysis. After the DEP process, the weight percentage of As(V) on the adsorbent surface increased to 0.96% from 0.5%. The ADS/DEP process could be a new efficient way to remove arsenic pollutant at high concentrations.

scholarly journals Removal of Cadmium from Industrial Wastewater using Electrocoagulation Process

2019 ◽  
Vol 26 (1) ◽  
pp. 24-34 ◽  
Author(s):  
Mohammed Alameen Salem ◽  
Najwa Majeed
Keyword(s):  
Heavy Metal ◽  
Removal Efficiency ◽  
Applied Voltage ◽  
Industrial Wastewater ◽  
Batch Reactor ◽  
Operating Parameters ◽  
Initial Concentration ◽  
Initial Ph ◽  
Electrocoagulation Process ◽  
Aluminum Electrodes

Cadmium is one of the heavy metal found in the wastewater of many industries. The electrocoagulation offers many advantages for the removal of cadmium over other methods. So the removal of cadmium from wastewater by using electrocoagulation was studied to investigate the effect of operating parameters on the removal efficiency. The studied parameters were the initial pH, initial concentration, and applied voltage. The study experiments were conducted in a batch reactor with  with two pairs of aluminum electrodes with dimension  and 2mm in thick with 1.5 cm space between them. The optimum removal was obtained at pH =7, initial concentration = 50 mg/L, and applied voltage = 20 V and it was 90%.

scholarly journals Effect of various parameters in removing Cr and Ni from model wastewater by using electrocoagulation

2013 ◽  
Vol 15 (4) ◽  
pp. 494-503 ◽  
Keyword(s):  
Removal Rate ◽  
Initial Value ◽  
Effective Surface ◽  
Initial Concentration ◽  
Iron Electrodes ◽  
Electrode Combination ◽  
Initial Ph ◽  
Electrocoagulation Process ◽  
Aluminum Electrodes ◽  
A Current

<p>The performance of a laboratory scale electrocoagulation system for the removal of Cr and Ni from model wastewater was studied systematically using iron and aluminum electrodes with an effective surface area of 13.8 cm2 and a distance of 4 cm. The influence of several parameters, such as initial concentration, electrode combination, current supply and initial pH was investigated during electrocoagulation process. The increase in initial concentration favored removal rate, did not affect nickel removal, but restricted chromium removal, thus indicating its required mechanism of reducing hexavalent ion to trivalent. The best removal efficiency, when metals existed separately in treated solutions, was accomplished with the use of iron electrodes for Cr (50%) and with aluminum electrodes for Ni (90%). When metals co-existed, iron electrodes achieved the best result, which was 76% for Cr and 82% for Ni, leaving 30 mg l-1 and 17 mg l-1 of residual concentrations, respectively, after 180 min of treatment. Solutions&rsquo; nominal pH appeared to be optimal, since increasing or decreasing their initial value did not benefit the electrocoagulation process. Chromium and nickel simultaneous removal was best achieved for conditions of 100 mg l-1 initial concentration, pH 5 and a current of 0.8 A.</p>

Removal of Arsenic from Micro-Polluted Water by Enhanced Coagulation Process

2012 ◽  
Vol 573-574 ◽  
pp. 594-598
Author(s):  
Ming Yu Li ◽  
Hai Bo Wu ◽  
Pei Pei Ma ◽  
Gang Cao ◽  
Lin Song ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Polluted Water ◽  
Raw Water ◽  
Residual Concentration ◽  
Initial Concentration ◽  
Enhanced Coagulation ◽  
Treated Water ◽  
Coagulation Process ◽  
Removal Of Arsenic

The removal of arsenic in micro-polluted water by enhanced coagulation with Poly Ferric Metasilicate (PFSS) was studied. The effects of dosage of PFSS , the dosage of oxidant and oxidize time on the removal efficiency of arsenic were discussed. Under the conditions of dosage of PFSS 0.065mmol/L, the residual concentration of arsenic in post-treated water was lower than 0.01 mg/L for raw water with initial concentration of arsenic 0.1 mg/L.

scholarly journals Electrocoagulation for the Removal of Copper and Zinc Ions from Water Using Iron Electrodes

2020 ◽  
Vol 7 (1) ◽  
pp. 37-43
Author(s):  
Majida K. Ahmad ◽  
Mais A. Mohammed ◽  
Mahmood M. Barbooti
Keyword(s):  
Metal Ions ◽  
Removal Efficiency ◽  
Metal Ion ◽  
Complete Removal ◽  
Atomic Absorption Spectrophotometry ◽  
Ion Concentration ◽  
Electrolysis Time ◽  
Initial Concentration ◽  
Adsorption Mechanisms ◽  
Iron Electrodes

Background: Many methods have been suggested for the removal of heavy metals from water to protect human health and the environment. Methods like precipitation and adsorption were proposed for this purpose. Objective: Electrocoagulation involves the generation of coagulant by the action of electricity on two metal electrodes (iron or aluminium) to aid the process of water decontamination. Methods: Electrodeposition cell was made with iron electrodes and application of voltage from the power supply (5-25 V) dipped in the working solution (Cu and Zn) at various concentrations (10-50 mg.mL-1) for 30-150 min. Samples were drawn and analysed by atomic absorption spectrophotometry. Results: The work indicated efficient removal of the metal ions. The dependence of removal efficiency on the three parameters was studied. The behaviour of the two metal ions was not identical. At low initial concentration, the electrolysis voltage was very important in the removal of Zn and Cu ions. Electrolysis time is essential in the removal process and shows a polynomial dependence of removal efficiency on time. Electrolysis time of 150 min resulted in almost complete removal (94-97%) regardless of the initial concentration. Both co-precipitation and adsorption mechanisms may be involved. Conclusion: The removal efficiency was directly dependent on the initial metal ion concentration and electrolysis time. The process gave removal efficiency for copper that is higher than that of the zinc.

Comparative Bio-sorption of Cadmium and Nickel Ions from Aqueous Solution onto Fibers of Date Palm using Fluidized Bed Column

2019 ◽  
Vol 70 (5) ◽  
pp. 1507-1512
Author(s):  
Baker M. Abod ◽  
Ramy Mohamed Jebir Al-Alawy ◽  
Firas Hashim Kamar ◽  
Gheorghe Nechifor
Keyword(s):  
Aqueous Solution ◽  
Heavy Metal ◽  
Metal Ions ◽  
Fluidized Bed ◽  
Removal Efficiency ◽  
Heavy Metal Ions ◽  
Date Palm ◽  
Operating Conditions ◽  
Initial Concentration ◽  
Bed Height

The aim of this study is to use the dry fibers of date palm as low-cost biosorbent for the removal of Cd(II), and Ni(II) ions from aqueous solution by fluidized bed column. The effects of many operating conditions such as superficial velocity, static bed height, and initial concentration on the removal efficiency of metal ions were investigated. FTIR analyses clarified that hydroxyl, amine and carboxyl groups could be very effective for bio-sorption of these heavy metal ions. SEM images showed that dry fibers of date palm have a high porosity and that metal ions can be trapped and sorbed into pores. The results show that a bed height of 6 cm, velocity of 1.1Umf and initial concentration for each heavy metal ions of 50 mg/L are most feasible and give high removal efficiency. The fluidized bed reactor was modeled using ideal plug flow and this model was solved numerically by utilizing the MATLAB software for fitting the measured breakthrough results. The breakthrough curves for metal ions gave the order of bio-sorption capacity as follow: Cd(II)]Ni(II).

scholarly journals The Efficacy of Whole Oyster Shells for Removing Copper, Zinc, Chromium, and Cadmium Heavy Metal Ions from Stormwater

2021 ◽  
Vol 13 (8) ◽  
pp. 4184
Author(s):  
Zhiying Xu ◽  
Caterina Valeo ◽  
Angus Chu ◽  
Yao Zhao
Keyword(s):  
Surface Area ◽  
Hexavalent Chromium ◽  
Removal Efficiency ◽  
Exposure Time ◽  
Food Waste ◽  
Positive Relationship ◽  
Copper Ions ◽  
Zinc Ions ◽  
Cadmium Ions ◽  
Initial Concentration

This research investigates the use of a common food waste product for removing four different types of metals typically found in stormwater. Whole, unprocessed oyster shells are explored for use in stormwater management infrastructure that addresses water quality concerns. The role of the shells’ surface area, exposure time, and the solution’s initial concentration on the removal efficiency were examined. Beaker scale experimental results demonstrated very good efficiency by the oyster shells for removing copper ions (80–95%), cadmium ions (50–90%), and zinc ions (30–80%) but the shells were not as effective in removing hexavalent chromium (20–60%). There was a positive relationship between initial concentration and removal efficiency for copper and zinc ions, a negative relationship for hexavalent chromium, and no relationship was found for cadmium ions. There was also a positive relationship between surface area and removal efficiency, and exposure time and removal efficiency. However, after a certain exposure time, the increase in removal efficiency was negligible and desorption was occasionally observed. A mid-scale experiment to mimic real-world conditions was conducted in which continuous inflow based on a 6-h design storm was applied to 2.7 kg of whole, unprocessed oyster shells. The shells provided an 86% and an 84% removal efficiency of cadmium and copper ions, respectively, in one day of hydraulic retention time. No removal was observed for hexavalent chromium, and zinc ion removal was only observed after initial leaching. This work has significant implications for sustainable stormwater infrastructure design using a material commonly found in municipal food waste.

scholarly journals Preliminary Study on the Use of Ozonation for the Degradation of Dithiocarbamate Residues in the Fruit Drying Process: Mancozeb Residue in Blackcurrant is the Example Used

2013 ◽  
Vol 53 (1) ◽  
pp. 48-52 ◽  
Author(s):  
Piotr Antos ◽  
Anna Kurdziel ◽  
Stanisław Sadło ◽  
Maciej Balawejder
Keyword(s):  
Aqueous Solution ◽  
Ozone Concentration ◽  
Gaseous Phase ◽  
Plant Material ◽  
Water Solution ◽  
Ozone Treatment ◽  
Drying Process ◽  
Initial Concentration ◽  
Preliminary Study ◽  
Treatment Procedures

Abstract In order to reduce the level of dithiocarbamate fungicide mancozeb residues in blackcurrants, two different ozone treatment procedures were evaluated. The first one entailed washing the plant material with an aqueous solution of ozone. This ozone enriched water solution allowed for a 59% reduction of mancozeb residues, compared with the initial concentration. The latter method was based on the utilization of ozone in a gaseous phase combined with a drying process. In that procedure, samples of blackcurrant fruit were exposed to a 19 ppm ozone concentration, and then the blackcurrants were dried. The utilization of ozone in a gaseous phase permitted a 38% reduction of mancozeb residues, in comparison with the initial concentration. As a result of the combination of both processes; ozonation and drying, a 58% reduction of mancozeb residues was achieved.

Degradation of Organophosphorus Pesticide in a Packed-Bed Plasma Reactor: Effects of Operating Parameters and Kinetics Study

2013 ◽  
Vol 781-784 ◽  
pp. 1637-1645 ◽  
Author(s):  
Ting Jun Ma ◽  
Yi Qing Xu
Keyword(s):  
Removal Efficiency ◽  
Flow Rate ◽  
Gas Flow ◽  
Plasma Reactor ◽  
Organophosphorus Pesticide ◽  
Packed Bed ◽  
Pulse Frequency ◽  
Gas Flow Rate ◽  
Peak Voltage ◽  
Initial Concentration

The degradation effectiveness and reaction kinetics of representative organophosphorus (OP) pesticide in a packed-bed plasma reactor have been studied. Important parameters, including peak voltage, pulse frequency, gas-flow rate, initial concentration, diameter of catalyst particles, and thickness of catalyst bed which influences the removal efficiency, were investigated. Experimental results indicated that rogor removal efficiency as high as 80% can be achieved at 35 kV with the gas flow rate of 800 mL/min and initial concentration of 11.2 mg/m3.The removal efficiency increased with the increase of pulsed high voltage, and pulse frequency, the decrease of the diameter of catalyst particles and the thickness of catalyst bed. Finally, a model was established to predict the degradation of the rogor, which generally can simulate the experimental measurements to some degree.

Sign in / Sign up

Export Citation Format

Share Document