scholarly journals Electrocoagulation removal of anthraquinone dye Alizarin Red S from aqueous solution using aluminum electrodes: kinetics, isothermal and thermodynamics studies

2016 ◽  
Author(s):  
Abideen Idowu Adeogun ◽  
Ramesh Babu Balakrishnan
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Current Density ◽  
Alizarin Red S ◽  
Isotherm Models ◽  
Alizarin Red ◽  
Anthraquinone Dye ◽  
First Order ◽  
Electrocoagulation Process ◽  
Pseudo First Order

<span lang="EN-US">Electrocoagulation (EC) was used for the removal of anthraquinone dye, Alizarin Red S (ARS) from aqueous solution, the process was carried out in a batch electrochemical cell with Al electrodes in monopolar connection. The effects of some important parameters such as current density, pH, temperature and initial dye concentration, on the process were investigated. Equilibrium was attained after 10 minutes at 30 oC. Pseudo-first-order, pseudo-second-order, Elovic, and Avrami kinetic models were used to test the experimental data in order to elucidate the kinetic of the electrocoagulation process; pseudo-first-order and Avrami models best fitted the data. Experimental data were analyzed using six isotherm models: Langmuir, Freudlinch, Redlich–Peterson, Temkin, Dubinin–Radushkevich and Sips isotherms and it was found that the data fitted well with Dubinin–Radushkevich and Sips isotherm model. The study showed that the process depend on current density, temperature, pH and initial dye concentration. The calculated thermodynamics parameters (∆G<sup>o</sup>, ∆H<sup>o</sup> and ∆S<sup>o</sup>) indicated that the process is spontaneous and endothermic in nature.</span>

Electrochemical Degradation of RDX in Aqueous Solution at Constructed Sb-Doped SnO2 Anode

2011 ◽  
Vol 396-398 ◽  
pp. 1803-1806
Author(s):  
Yong Chen ◽  
Lei Hong ◽  
Wei Shi ◽  
Wei Qing Han ◽  
Lian Jun Wang
Keyword(s):  
Aqueous Solution ◽  
Current Density ◽  
Order Reaction ◽  
Electrochemical Degradation ◽  
Kinetics Analysis ◽  
Pseudo First Order Reaction ◽  
Initial Concentration ◽  
First Order ◽  
Sno2 Electrode ◽  
Pseudo First Order

The constructed Sb-doped SnO2 electrode was obtained for electrochemical degradation of RDX. The influences of current density and initial concentration of RDX on electrochemical degradation of RDX were studied. Kinetics analysis shows that the electrochemical degradation of RDX follows the pseudo first-order reaction. The mechanism of electrochemical degradation of RDX was also discussed.

scholarly journals Investigation of the Adsorption Potentials of an Organic Adsorbent for Phenol Removal from Aqueous Solution

2021 ◽  
pp. 124-134
Author(s):  
C.E. Muko-Okoro ◽  
I.A. Obiora-Okafo ◽  
J.N. Ndive
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Adsorption Kinetics ◽  
Contact Time ◽  
Phenol Removal ◽  
Initial Concentration ◽  
First Order ◽  
Pseudo Second Order ◽  
Pseudo First Order ◽  
Better Than

Phenol is a prevalent pollutant found in many industrial wastewaters, and it is paid singular attention because of its special features including high toxicity, carcinogenic properties, and vital cumulative ability that affects the health of humans and the environment. The current study investigated the removal of phenol from synthetic aqueous solutions using prepared Moringaoleifera seed shell as an adsorbent. The efficiency of phenol removal by Moringaoleifera seed shell was evaluated in a batch system, and different parameters such as initial concentration of phenol (100, 200, 300, 400 and 500 mg/L), contact time (10, 20, 30, 40, 50 and 60 min), and adsorbent dosage (0.2, 0.4, 0.6, 0.8, and 1.0 g) were studied. The results showed that the highest percentage of phenol removal by the ash occurred at 0.8 g dosage, contact time of 40 min, and initial concentration of 500 mg/L giving 87.2% phenol removal. The adsorption process was modeled with Langmuir and Freundlich isotherms and adsorption kinetics (pseudo-first order and pseudo-second order) at controlled temperatures. The results showed that the experimental data fitted the Langmuir (R2 = 0.8338) much better than the Freundlich model (R2 = 0.7314). For the analysis of the adsorption kinetics, the results showed that the experimental data fitted the pseudo-second order kinetics (R2 = 0.999) much better than the pseudo-first order kinetics (R2 = 0.5042). In general, the results of this study revealed that Moringaoleifera seed shell has suitable potential for use in removing phenol from aqueous solution on operation and practical scales due to its availability and organic nature.

Preparation of crosslinked chitosan magnetic membrane for cations sorption from aqueous solution

2017 ◽  
Vol 75 (9) ◽  
pp. 2034-2046 ◽  
Author(s):  
Adnan Khan ◽  
Samina Begum ◽  
Nauman Ali ◽  
Sabir Khan ◽  
Sajjad Hussain ◽  
...  
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Magnetic Particles ◽  
Isotherm Models ◽  
Chitosan Membrane ◽  
Dilute Aqueous Solution ◽  
Chitosan Membranes ◽  
The Fourier Transform ◽  
Time Required

A chitosan magnetic membrane was prepared in order to confer magnetic properties to the membrane, which could be used for the removal of cations from aqueous solution. The crosslinked magnetic membrane was compared with pristine chitosan membrane in term of stability, morphology and cation adsorption capacity. The fabricated magnetic materials are thermally stable as shown by thermogravimetric curves. The membrane containing nickel magnetic particles (CHNiF-G) shows high thermal stability compared to the other membranes. The Fourier transform infrared spectroscopy showed successful preparation of chitosan magnetic membrane. Scanning electron microscopy micrographs showed the rough surface of the membrane with increased porosity. The prepared chitosan membranes were applied to cations of copper, nickel and lead in dilute aqueous solution. The chitosan membrane showed the following adsorption order for metallic cations: Cu2+ &gt; Ni2+ &gt; Pb2+, while CHNiF-G showed higher capacity, 3.51 mmol g−1 for copper, reflecting the improvement in adsorption capacity, since the amount of copper on pristine chitosan gave 1.40 mmol g−1. The time required for adsorption to reach to the equilibrium was 6 h for the selected cations using different chitosan membranes. The kinetic study showed that adsorption followed pseudo-second order kinetics. The most commonly used isotherm models, Freundlich, Langmuir and Temkin, were applied to experimental data using linear regression technique. However, The Temkin model fits better to experimental data.

scholarly journals Harnessing of Newly Tailored Poly (Acrylonitrile)-Starch Nanoparticle Graft Copolymer for Copper Ion Removal via Oximation Reaction

2021 ◽  
Author(s):  
khaled Mostafa ◽  
H. Ameen ◽  
A. Ebessy ◽  
A. El-Sanabary
Keyword(s):  
Experimental Data ◽  
Adsorption Capacity ◽  
Graft Copolymer ◽  
Adsorption Kinetics ◽  
Copper Ions ◽  
Copper Ion ◽  
Second Order ◽  
First Order ◽  
Pseudo Second Order ◽  
Pseudo First Order

Abstract Our recently tailored and fully characterized poly (AN)-starch nanoparticle graft copolymer having 60.1 G.Y. % was used as a starting substrate for copper ions removal from waste water effluent after chemical modification with hydroxyl amine via oximation reaction. This was done to change the abundant nitrile groups in the above copolymer into amidoxime one and the resultant poly (amidoxime) resin was used as adsorbent for copper ions. The resin was characterized qualitatively via rapid vanadium ion test and instrumentally by FT-IR spectra and SEM morphological analysis to confirm the presence of amidoxime groups. The adsorption capacity of the resin was done using the batch technique, whereas the residual copper ions content in the filtrate before and after adsorption was measured using atomic adsorption spectrometry. It was found that the maximum adsorption capacity of poly (amidoxime) resin was 115.2 mg/g at pH 7, 400ppm copper ions concentration and 0.25 g adsorbent at room temperature. The adsorption, kinetics and isothermal study of the process is scrutinized using different variables, such as pH, contact time, copper ion concentration and adsorbent dosage. Different kinetics models comprising the pseudo-first-order and pseudo-second-order have been applied to the experimental data to envisage the adsorption kinetics. It was found from kinetic study that pseudo-second-order rate equation was better than pseudo-first-order supporting the formation of chemisorption process. While, in case of isothermal study, the examination of calculated correlation coefficient (R2) values showed that the Langmuir model provide the best fit to experimental data than Freundlich one.

scholarly journals Electrochemical Removal of Chromium (VI) from Wastewater

2019 ◽  
Author(s):  
Hao Peng ◽  
Yumeng Leng ◽  
Jing Guo
Keyword(s):  
Reaction Temperature ◽  
Current Density ◽  
Reduction Rate ◽  
Reduction Process ◽  
Order Equation ◽  
First Order ◽  
Chromium Vi ◽  
Reduction Efficiency ◽  
Pseudo First Order ◽  
Electrochemical Removal

Removal of hexavalent chromium had attracted much more attention as it was a hazardous contaminant. Electrochemical reduction technology was applied to removal chromium (VI) from wastewater. The mechanism and parameters affect the reduction process were investigated. The results showed that the reduction efficiency was significantly affected by the concentration of H2SO4, current density and reaction temperature. And the reduction efficiency was up to 86.45% at concentration of H2SO4 of 100g/L, reaction temperature of 70 ℃, current density at 50 A/m2, reaction time at 180 min and stirring rate of 500 rpm. The reduction process of chromium (VI) was followed pseudo-first-order equation, and the reduction rate could be expressed as Kobs = k [H2SO4]1• [j] 4•exp-4170/RT.

scholarly journals Photocatalytic degradation of sulfamethazine in aqueous solution using ZnO with different morphologies

2018 ◽  
Vol 5 (4) ◽  
pp. 171457 ◽  
Author(s):  
Zhigang Yi ◽  
Juan Wang ◽  
Tao Jiang ◽  
Qiong Tang ◽  
Ying Cheng
Keyword(s):  
Aqueous Solution ◽  
Photocatalytic Degradation ◽  
Reaction System ◽  
Degradation Pathway ◽  
Order Reaction ◽  
Pseudo First Order Reaction ◽  
First Order ◽  
Different Shapes ◽  
Pseudo First Order ◽  
Release Ratio

In this study, photocatalytic experiments of 20 mg l −1 sulfamethazine (SMN) in aqueous solution containing ZnO with different morphologies, tetra-needle-like ZnO (T-ZnO), flower-like ZnO (F-ZnO) and nanoparticles ZnO (P-ZnO), were performed. The results indicated that photocatalytic degradation of SMN was effective and followed the pseudo-first-order reaction, but the degree of SMN mineralization showed obvious differences using ZnO with different shapes. After 12 h irradiation, 86%, 71% and 50% of the initial total organic carbon was eliminated in SMN suspension containing T-ZnO, F-ZnO and P-ZnO, respectively. The release ratio of sulfur was close to 100% in the presence of T-ZnO, but reached to 86% and 67% in the presence of F-ZnO and P-ZnO, respectively. The release ratio of nitrogen was about 76%, 63% and 40% using T-ZnO, F-ZnO and P-ZnO as photocatalyst, respectively. The morphology of ZnO played an important role in determining its catalytic activity. Seven intermediates were observed and identified in the UV/T-ZnO reaction system by LC-MS/MS analysis, and a possible degradation pathway was proposed.

scholarly journals Removal of copper ions from aqueous solution using NaOH-treated rice husk

2020 ◽  
Vol 3 (6) ◽  
pp. 857-870
Author(s):  
Shagufta Zafar ◽  
Muhammad Imran Khan ◽  
Mushtaq Hussain Lashari ◽  
Majeda Khraisheh ◽  
Fares Almomani ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Rice Husk ◽  
Contact Time ◽  
Copper Ions ◽  
Analytical Techniques ◽  
First Order ◽  
Freundlich Isotherms ◽  
Naoh Solution ◽  
Pseudo Second Order ◽  
Pseudo First Order

AbstractThe present study investigates the removal of copper ions (Cu (II)) from aqueous solution using chemically treated rice husk (TRH). The chemical treatment was carried out using NaOH solution and the effect of contact time (tc), adsorbent dosage (Dad), initial Cu (II) concentration ([Cu]i), and temperature (T) on the percentage removals of Cu (II) (%RCu) were investigated. Different analytical techniques (FTIR, SEM, and EDX) were used to confirm the adsorption (ads) of Cu (II) onto the TRH. The ads kinetics was tested against pseudo-first-order (PFO) and pseudo-second-order (PSO) models as well as Langmuir and Freundlich isotherms. Treating RH with NaOH altered the surface and functional groups, and on the surface of RH, the ionic ligands with high electro-attraction to Cu increased and thus improved the removal efficiency. The %RCu decreased by increasing the [Cu]i and increased by increasing the ct, Dad, and T. Up to 97% Cu removal was achieved in ct of 30 min using Dad of 0.3 g [Cu]i of 25 mg L−1 and T = 280 K. The ads of Cu on TRH is endothermic, spontaneous, follows Langmuir isotherms, and exhibited a PSO kinetics. Moreover, the TRH was successfully regenerated and used for further adsorption cycles using 1 M HNO3.

scholarly journals Oxidative Degradation of Amoxicillin in Aqueous Solution by Thermally Activated Persulfate

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Juanjuan Zhao ◽  
Yujiao Sun ◽  
Fachao Wu ◽  
Minjian Shi ◽  
Xurui Liu
Keyword(s):  
Aqueous Solution ◽  
Reaction Temperature ◽  
Oxidative Degradation ◽  
Water Remediation ◽  
Order Kinetic ◽  
Production Chain ◽  
First Order ◽  
Thermally Activated ◽  
Pseudo First Order ◽  
Activated Persulfate

Antibiotic residues and antibiotic resistance genes (ARGs) pose a great threat to public health and food security via the horizontal transfer in the food production chain. Oxidative degradation of amoxicillin (AMO) in aqueous solution by thermally activated persulfate (TAP) was investigated. The AMO degradation followed a pseudo-first-order kinetic model at all tested conditions. The pseudo-first-order rate constants of AMO degradation well-fitted the Arrhenius equation when the reaction temperature ranged from 35°C to 60°C, with the apparent activate energy of 126.9 kJ·mol−1. High reaction temperature, high initial persulfate concentration, low pH, high Cl− concentration, and humic acid (HA) concentration increased the AMO degradation efficiency. The EPR test demonstrated that both ·OH and SO4·− were generated in the TAP system, and the radical scavenging test identified that the predominant reactive radical species were SO4·− in aqueous solution without adjusting the solution pH. In groundwater and drinking water, AMO degradation suggested that TAP could be a reliable technology for water remediation contaminated by AMO in practice.

Kinetics of Glyphosate Adsorption on Composite Resin from Aqueous Solution

2013 ◽  
Vol 803 ◽  
pp. 157-160
Author(s):  
Zhen Zhen Kong ◽  
Dong Mei Jia ◽  
Su Wen Cui
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Composite Resin ◽  
Order Equation ◽  
Second Order ◽  
First Order ◽  
Basic Resin ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Best Fit

The composite weakly basic resin (D301Fe) was prepared and examined using scanning electron microscopy and Fourier transform infrared spectroscopy. The adsorption kinetics of glyphosate from aqueous solution onto composite weakly basic resin (D301Fe) were investigated under different conditions. The experimental data was analyzed using various adsorption kinetic models like pseudo-first order, the pseudo-second order, the Elovich and the parabolic diffusion models to determine the best-fit equation for the adsorption of glyphosate onto D301Fe. The results show that the pseudo-second order equation fitted the experimental data well and its adsorption was chemisorption-controlled.

UV-Vis/Ferrioxalate/H2O2 System on Degradation of Anthraquinone Dye Wastewater

2011 ◽  
Vol 239-242 ◽  
pp. 2597-2601
Author(s):  
Wei Ding ◽  
Ming Ke ◽  
Zhao Zheng Song
Keyword(s):  
Organic Carbon ◽  
Optimum Condition ◽  
Chemical Oxygen Demand ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Optimum Concentration ◽  
Dye Wastewater ◽  
Anthraquinone Dye ◽  
First Order ◽  
Pseudo First Order

Anthraquinone dye Reactive Blue (KN-R) is first selected as the model dye to test the treatment of UV-vis/Ferrioxalate/H2O2system. The effect of parameters Fe2+/H2O2, pH and H2C2O4are synthetically assessed. The optimum concentration is obtained at 1:15 of Fe2+/H2O2and 30mg·L-1of H2C2O4 at pH=3.0 in 30min. Under the optimum condition, the removal rate of color, chemical oxygen demand (COD) and total organic carbon (TOC) are more than 99%, 87.7% and 66.8% respectively. The results show that the reaction accorded with a pseudo-first-order and the degeneration velocity of KN-R is 0.2459[dye](mg·L-1/min).

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