scholarly journals Removing The Acid Orange 12 Azo Dye from Aqueous Solution Using Sodium Hypochlorite, A Kinetic and Thermodynamic Study

2022 ◽  
Vol 961 (1) ◽  
pp. 012056
Author(s):  
A. B. Hameed ◽  
A. B. Dekhyl ◽  
W. M. Sh. Alabdraba

Abstract This study investigated the feasibility of using sodium hypochlorite as an advanced oxidation process to remove Acid Orange 12 azo dye from wastewater. For this purpose, batch reactor experiments were done. Several variables to address the efficiency of using this process were considered. These variables are initial pH (5, 7, and 9), the concentration of hypochlorite (50 – 250 mg/l), temperature (20-50) degrees Celsius, and time of electrolysis (1-75) min. also investigate the effects of UV on the process was done. Experimental results showed that the color removal efficiency using NaOCl with UV is more effective than NaOCl alone. The highest removal efficiency was obtained by increasing the concentration of NaOCl from (50-250mg/l) at PH=5. When the solution temperature was increased from (20-50) °C, the removal efficiency increased, and at the same time, the time required was reduced from (20-5) minutes to obtain the highest removal efficiency. The kinetic study also showed that the oxidation process follows a second-order reaction. The thermodynamic functions indicate that the response is spontaneous, endothermic, and increases randomness.

Author(s):  
Mohammad E. Olya ◽  
Masoud B. Kasiri ◽  
Hamid Aleboyeh ◽  
Azam Aleboyeh

AbstractThe mineralization of C.I. Acid Orange 7 (AO7) azo dye by UV/H2O2 Advanced Oxidation Process was studied in a flux through annular photoreactor. An experimental design based on Response Surface Methodology (RSM) was applied to evaluate the simple and combined effects of influencing independent parameters on mineralization efficiency and optimising the operating conditions of the treatment process. A 2


2019 ◽  
Vol 1176 ◽  
pp. 766-776 ◽  
Author(s):  
Mohammad Malakootian ◽  
Majid Amiri Gharaghani ◽  
Abbas Dehdarirad ◽  
Mehrdad Khatami ◽  
Mohammad Ahmadian ◽  
...  

2020 ◽  
Vol 49 (5) ◽  
pp. 363-368
Author(s):  
Maryam Khashij ◽  
Mohammad Mehralian ◽  
Zahra Goodarzvand Chegini

Purpose The purpose of this study to investigate acetaminophen (ACT) degradation efficiencies by using ozone/persulfate oxidation process in a batch reactor. In addition, the effects of various parameters on the ACT removal efficiency toward pathway inference of ACT degradation were investigated. Design/methodology/approach The experiments were in the 2 L glass vessels. Ozone gas with flow rate at 70 L.h−1 was produced by ozone generator. After the adjustment of the pH, various dosages of persulfate (1, 3, 5, 7 and 9 mmol.L−1) were then added to the 500 mL ACT-containing solution with 150 mg.L−1 of concentration. Afterward, ozone gas was diffused in glass vessels. The solution after reaction flowed into the storage tank for the detection. The investigated parameters included pH and the amount of ozone and persulfate addition. For comparison of the ACT degradation efficiency, ozone/persulfate, ozone and persulfate oxidation in reactor was carried out. The ACT concentration using a HPLC system equipped with 2998 PDA detector was determined at an absorbance of 242 nm. Findings ACT degradation percentage by using ozone or persulfate in the process were at 63.7% and 22.3%, respectively, whereas O3/persulfate oxidation process achieved degradation percentage at 91.4% in 30 min. Degradation efficiency of ACT was affected by different parameter like pH and addition of ozone or persulfate, and highest degradation obtained when pH and concentrations of persulfate and ozone was 10 and 3 mmol.L−1 and 60 mg.L−1, respectively. O3, OH• and SO4− were evidenced to be the radicals for degradation of ACT through direct and indirect oxidation. Gas chromatography–mass spectrometer analysis showed intermediates including N-(3,4-dihydroxyphenyl) formamide, hydroquinone, benzoic acid, 4-methylbenzene-1,2-diol, 4-aminophenol. Practical implications This study provided a simple and effective way for degradation of activated ACT as emerging contaminants from aqueous solution. This way was conducted to protect environment from one of the most important and abundant pharmaceutical and personal care product in aquatic environments. Originality/value There are two main innovations. One is that the novel process is performed successfully for pharmaceutical degradation. The other is that the optimized conditions are obtained. In addition, the effects of various parameters on the ACT removal efficiency toward pathway inference of ACT degradation were investigated.


2016 ◽  
Vol 74 (8) ◽  
pp. 1946-1952 ◽  
Author(s):  
Peng Zhou ◽  
Bei Liu ◽  
Jing Zhang ◽  
Yongli Zhang ◽  
Gucheng Zhang ◽  
...  

A highly efficient advanced oxidation process for the degradation of benzoic acid (BA) during activation of peroxomonosulfate (PMS) by nanoscale zero-valent copper (nZVC) in acidic solution is reported. BA degradation was almost completely achieved after 10 min in the nZVC/PMS process at initial pH 3.0. PMS could accelerate the corrosion of nZVC in acidic to release Cu+ which can further activate PMS to produce reactive radicals. Both sulfate radical (SO4−•) and hydroxyl radical (•OH) were considered as the primary reactive oxidant in the nZVC/PMS process with the experiments of methyl (MA) and tert-butyl alcohol quenching. Acidic condition (initial pH ≤ 3.0) facilitated BA degradation and pH is a decisive factor to affect the oxidation capacity in the nZVC/PMS process. Moreover, BA degradation in the nZVC/PMS process followed the pseudo-first-order kinetics, and BA degradation efficiency increased with the increase of the nZVC dosage.


e-xacta ◽  
2016 ◽  
Vol 9 (2) ◽  
Author(s):  
Denis Rafael de Souza Lima ◽  
Isabela Luiza Alves de Almeida ◽  
Vanderlei Inácio de Paula

<p>Neste trabalho avaliou-se a aplicação do processo oxidativo avançado (POA) de foto-peroxidação (UV/H<sub>2</sub>O<sub>2</sub>) na degradação do azocorante têxtil comercial Azul Reativo 5G. Foram preparadas soluções sintéticas contendo o corante e tratadas através do respectivo POA, sendo a eficiência do tratamento avaliada através dos seguintes parâmetros: descoloração, redução da demanda química de oxigênio (DQO) e ecotoxicidade com sementes de Lactuca sativa. Após 30 minutos de tratamento em condições otimizadas na presença de peróxido de hidrogênio e radiação ultravioleta, foi observada descoloração na ordem de 91,8% sem redução significativa da DQO (1,8%), além de diminuição da ecotoxicidade da solução, indicando a viabilidade da aplicação do processo UV/H<sub>2</sub>O<sub>2</sub> para tratamento de resíduos líquidos contendo este azocorante.</p><p>ABSTRACT</p><p>In the present paper was evaluated the application of advanced oxidation process (AOP) photo-peroxidation (UV/H<sub>2</sub>O<sub>2</sub>) applied to degradation of the commercial textile azo dye Reactive Blue 5G. Synthetic solutions were prepared containing the dye, treated through the respective AOP and the efficiency of the treatment evaluated by the following parameters: discoloration, reduction of chemical oxygen demand (COD) and ecotoxicity with Lactuca sativa seeds. After 30 minutes of treatment in optimized conditions in the presence of hydrogen peroxide and ultraviolet radiation, discoloration was observed in order of 91.8% without significant reduction of COD (1.8%), but decrease in the ecotoxicity of the solution, indicating feasibility of the process UV/H<sub>2</sub>O<sub>2</sub> for treating liquid wastes containing this azo dye.</p>


Sign in / Sign up

Export Citation Format

Share Document