scholarly journals Removal of Emerging Contaminants in Wastewater by Sonolysis, Photocatalysis and Ozonation

2018 ◽  
Vol 21 (2) ◽  
pp. 98-105 ◽  
Keyword(s):  
Rate Constants ◽  
Photocatalytic Oxidation ◽  
Advanced Oxidation Processes ◽  
Emerging Contaminants ◽  
Removal Rate ◽  
Experimental Conditions ◽  
Oxidation Processes ◽  
First Order ◽  
Performance Variation ◽  
Pseudo First Order

<p>Three different advanced oxidation processes (AOPs) were applied to investigate the removal of emerging contaminants (ECs) i.e. sulfamethoxazole (SMX), diclofenac (DCF) and carbamazepine (CBZ) in synthetically prepared solutions. The degradation of these substances was carried out by ozonation, sonolysis and photocatalytic oxidation, as well as by different combinations of these processes. The objectives of this work were to evaluate the removal efficiency in each AOP and to assess the performance variation of sonolysis in combination with other AOPs. The best performances were achieved by sonocatalysis, which resulted in the removal of the selected pharmaceuticals in the range between 37% and 47%. Under similar experimental conditions, the removal of the selected ECs by single compounds by ozonation was slightly lower than the removal of respective compounds in the mixture. Moreover, pseudo first-order removal rate constants of photocatalytic mineralization were determined as 9.33×10-2, 4.90×10-3, 1.06×10-2 min-1 for SMX, DCF and CBZ, respectively.</p>

Degradation of propoxycarbazone-sodium with advanced oxidation processes

2011 ◽  
Vol 11 (1) ◽  
pp. 129-134 ◽  
Author(s):  
A. Dulov ◽  
N. Dulova ◽  
Y. Veressinina ◽  
M. Trapido
Keyword(s):  
Rate Constants ◽  
Advanced Oxidation Processes ◽  
Advanced Oxidation ◽  
Fenton Process ◽  
Oxidation Processes ◽  
First Order ◽  
Order Rate ◽  
Conversion Time ◽  
Pseudo First Order ◽  
Kinetics Of

The degradation of propoxycarbazone-sodium, an active component of commercial herbicide, in aqueous solution with ozone, UV photolysis and advanced oxidation processes: O3/UV, O3/UV/H2O2, H2O2/UV, and the Fenton process was studied. All these methods of degradation proved feasible. The kinetics of propoxycarbazone-sodium degradation in water followed the pseudo-first order equation for all studied processes except the Fenton treatment. The application of schemes with ozone demonstrated low pseudo-first order rate constants within the range of 10−4 s−1. Addition of UV radiation to the processes improved the removal of propoxycarbazone-sodium and increased the pseudo-first order rate constants to 10−3 s−1. The Fenton process was the most efficient and resulted in 5 and 60 s of half-life and 90% conversion time of propoxycarbazone-sodium, respectively, at 14 mM H2O2 concentration. UV treatment and the Fenton process may be recommended for practical application in decontamination of water or wastewater.

Degradation of Sulfa Pharmaceuticals in Aquatic Environment by O3 and UV/TiO2 Processes

2011 ◽  
Vol 255-260 ◽  
pp. 4222-4226
Author(s):  
Li Chin Chuang ◽  
Chin Hsiang Luo ◽  
Sing Wei Huang ◽  
Chun Ju Lin
Keyword(s):  
Rate Constants ◽  
Aquatic Environment ◽  
Advanced Oxidation Processes ◽  
Advanced Oxidation ◽  
Complete Removal ◽  
Oxidation Processes ◽  
First Order ◽  
First Order Kinetics ◽  
Pseudo First Order ◽  
Removal Efficiencies

The removal efficiencies of sulfamerazine (SMR) and sulfamethoxypyridazine (SMP) in aqueous solutions were studied using advanced oxidation technologies. The results show similar removal kinetics for two sulfa pharmaceuticals and that complete removal of all is achieved within 90 min of ozonation at the concentration of O3 (1 mgL-1) without controlling the pH. The rate constants were calculated as 0.0143 and 0.0113 min-1 for SMR and SMP, respectively. The catalysts exhibited a superior removal efficiency of SMP to those of SMR with a TiO2 concentration of 2.0 gL-1. The disappearance of these two sulfa pharmaceuticals follows a pseudo-first-order kinetics according to the Langmuir-Hinshelwood (L-H) model. The rate constants were calculated as 5 × 10-3 and 6 × 10-4 min-1 for SMR and SMP, respectively. Advanced oxidation processes (AOPs), such as O3 and UV/TiO2 processes should be an effective treatment for removing these sulfa pharmaceuticals.

Kinetic study of dye removal using TiO2 supported on polyethylene terephthalate by advanced oxidation processes through neural networks

2019 ◽  
Vol 79 (6) ◽  
pp. 1134-1143 ◽  
Author(s):  
Ada Azevedo Barbosa ◽  
Ramon Vinicius Santos de Aquino ◽  
Naiana Santos da Cruz Santana Neves ◽  
Renato Falcão Dantas ◽  
Marta Maria Menezes Bezerra Duarte ◽  
...  
Keyword(s):  
Kinetic Study ◽  
Polyethylene Terephthalate ◽  
Advanced Oxidation Processes ◽  
Dye Removal ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Order Model ◽  
Oxidation Processes ◽  
First Order ◽  
Pseudo First Order

Abstract This work investigated the efficiency of polyethylene terephthalate (PET) as support material for TiO2 films in the photocatalytic degradation of red Bordeaux and yellow tartrazine dyes. The optimum operating conditions were determined by a factorial design, which resulted after 180 min of treatment in degradations of 99.5% and 99.1% for the UVC/H2O2/TiO2Sup and solar/H2O2/TiO2Sup systems, respectively. For the kinetic study, the experimental data fitted to the pseudo-first-order model and the calculated kinetic constants (k) values were 0.03 min−1 for the UVC/H2O2/TiO2Sup system and 0.0213 min−1 for the system solar/H2O2/TiO2Sup. It was verified that TiO2 supported in the PET remained with high degradation efficiency even after five cycles of reuse, indicating a good stability of the photocatalyst in the support. A significant reduction of TOC content was also observed along the reaction time. The phytotoxicity bioassay with Lactuca sativa demonstrated that after treatment with UVC/H2O2/TiO2Sup and solar/H2O2/TiO2SUP, an increase in IC50 and consequently lower toxicity was observed.

Degradation of Butylparaben by Ozonation and UV/TiO2 Processes

2012 ◽  
Vol 488-489 ◽  
pp. 159-163 ◽  
Author(s):  
Li Chin Chuang ◽  
Chin Hsiang Luo ◽  
Ming Chieh Chuang ◽  
Miao Chi Wang
Keyword(s):  
Breast Cancer ◽  
Antimicrobial Agent ◽  
Advanced Oxidation Processes ◽  
Estrogenic Activity ◽  
Reaction Rates ◽  
Alkaline Condition ◽  
Oxidation Processes ◽  
First Order ◽  
First Order Kinetics ◽  
Pseudo First Order

Butylparaben is widely used as a bactericide and as an antimicrobial agent in the formation of personal care products (PCPs). Owing to a certain estrogenic activity, a possible relationship with breast cancer has been proved by many researchers. The removal efficiency of butylparaben in aqueous solutions was studied using advanced oxidation processes (AOPs). These results indicate that the reaction rates for the ozonation of butylparaben in water are higher under the concentration of ozone 5 mg/L in alkaline condition. The original concentration of butylparaben almost degraded within 50, 30, and 20 min at ozone concentrations of 1, 3, and 5 mg/L, respectively at pH 11 runs. The ozonation imposed butylparaben with a time dependence that appeared to follow pseudo first-order kinetics. The original butylparaben was degraded 50 %, 40%, 35%, and 32% within 24 hr at pH 3, 6, 9, and 11 respectively by UV/TiO2 process in the O2-sparged concentration of 30 mg/L. The rate constants are 0.045, 0.043, 0.025, and 0.020 hr-1 at the butylparaben concentrations of 10.30, 20.60, 30.90, and 41.20 μM, respectively.

A novel solution for hydroxylated PAHs removal by oxidative coupling reaction using Mn oxide

2008 ◽  
Vol 58 (1) ◽  
pp. 171-178 ◽  
Author(s):  
Ki-Hoon Kang ◽  
Dong-Min Lim ◽  
Hyun-Sang Shin
Keyword(s):  
Rate Constants ◽  
Oxidative Coupling ◽  
Coupling Reaction ◽  
Experimental Conditions ◽  
Oxidative Transformation ◽  
First Order ◽  
Oxidative Coupling Reaction ◽  
Order Rate ◽  
Mn Oxide ◽  
Pseudo First Order

In this study, removals of 1-naphthol by oxidative-coupling reaction using birnessite, one of the natural Mn oxides present in soil, was investigated in various experimental conditions (reaction time, Mn oxide loadings, pH). The removal efficiency of 1-naphthol by birnessite was high in all the experimental conditions, and UV-visible and mass spectrometric analyses on the supernatant after reaction confirmed that the reaction products were oligomers formed by oxidative-coupling reaction. Pseudo-first order rate constants, k, for the oxidative transformation of 1-naphthol by birnessite was derived from the kinetic experiments under various amounts of birnessite loadings, and using the observed pseudo-first order rate constants with respect to birnessite loadings, the surface area normalised specific rate constant, ksurf, was also determined to be 9.3 × 10−4 (L/m2·min) for 1-naphthol. In addition, the oxidative transformation of 1-naphthol was found to be dependent on solution pH, and the pseudo-first order rate constants were increased from 0.129 at pH 10 to 0.187 at pH 4.

scholarly journals Removal of sulfamethizole from aqueous solution using advanced oxidation processes: effects of pH and salinity

2020 ◽  
Vol 82 (11) ◽  
pp. 2425-2431
Author(s):  
A. M. Wang ◽  
C. H. Wu ◽  
E. H. Huang
Keyword(s):  
Advanced Oxidation Processes ◽  
Advanced Oxidation ◽  
Mineralization Rate ◽  
Sodium Persulfate ◽  
Oxidation Processes ◽  
First Order ◽  
Predominant Species ◽  
First Order Kinetics ◽  
Effects Of Ph ◽  
Pseudo First Order

Abstract This study investigates the removal of sulfamethizole (SFZ) in ozone (O3), O3/Na2S2O8 (sodium persulfate), UV/Na2S2O8, UV/O3, and UV/O3/Na2S2O8 systems. The effects of pH and salinity on SFZ mineralization were evaluated. The mineralization of SFZ followed pseudo-first-order kinetics. At pH 5, the rate constants of SFZ mineralization in O3, O3/Na2S2O8, UV/Na2S2O8, UV/O3, and UV/O3/Na2S2O8 systems were 0.576, 0.924, 0.702, 1.26, and 5.21 h−1, respectively. The SFZ mineralization rate followed the order pH 5 &gt; pH 7 &gt; pH 9 in all tested advanced oxidation processes. Salinity increased the rate of SFZ mineralization in O3 and O3/Na2S2O8 systems and decelerated it in UV/Na2S2O8, UV/O3, and UV/O3/Na2S2O8 systems. UV/O3/Na2S2O8 was the best system for mineralizing SFZ, and sulfate radicals were the predominant species in UV/O3/Na2S2O8.

scholarly journals Paracetamol degradation and kinetics by advanced oxidation processes (AOPs): Electro-peroxone, ozonation, goethite catalyzed electro-fenton and electro-oxidation

2020 ◽  
Vol 26 (2) ◽  
pp. 180332-0
Author(s):  
Hazal Öztürk ◽  
Sibel Barışçı ◽  
Ozge Turkay
Keyword(s):  
Hydroxyl Radicals ◽  
Advanced Oxidation Processes ◽  
Advanced Oxidation ◽  
Complete Removal ◽  
Reaction Intermediates ◽  
Optimum Conditions ◽  
Oxidation Processes ◽  
First Order ◽  
Electro Oxidation ◽  
Pseudo First Order

The advanced oxidation of paracetamol (PCT), frequently used analgesic, promoted by electro-oxidation (EOX), goethite catalyzed electro-Fenton (GEF) with goethite, ozonation and electro-peroxone (E-peroxone) was investigated. The degradation efficiency of the processes was evaluated considering the decay of PCT versus time. All the processes showed pseudo-first order character for PCT degradation. kobs values, at optimum conditions for an individual process, were defined as 0.0022, 0.0029, 0.0870 and 0.1662 min-1 for EOX, GEF, ozonation and E-peroxone processes, respectively. Where EOX and GEF processes showed poor degradation efficiencies, novel E-peroxone process provided complete removal of PCT. The degradation of the PCT would mostly occur by OH• and molecular O3 due to the higher rate constants achieved at E-peroxone and ozonation. Conversely, with lower kobs values gained at EOX, hydroxyl radicals would not contribute noticeably to the PCT degradation. In GEF process, due to relatively lower OH• production rate, lower kobs values were obtained for the degradation of PCT. The formation of reaction intermediates, aromatics and carboxylic acids, was also determined in this study.

β-endosulfan removal from water by ozone oxidation

2004 ◽  
Vol 48 (11-12) ◽  
pp. 511-517 ◽  
Author(s):  
M.S. Yazgan ◽  
C. Kinaci
Keyword(s):  
Removal Rate ◽  
Batch Reactor ◽  
Temperature Dependent ◽  
Experimental Conditions ◽  
First Order ◽  
Oxidation Rates ◽  
Dependent Rate ◽  
Rate Of Reaction ◽  
Pseudo First Order ◽  
Kinetics Of

β-endosulfan solutions were ozonated in a lab scale semi-batch reactor in various experimental conditions. Ozonation kinetics of β-endosulfan and effects of some parameters such as pH, temperature, partial pressure and ozone dosage on oxidation were investigated. Increasing ozone dosage and decreasing of temperature and pH increased the oxidation rate of β-endosulfan. Maximum 97% of β-endosulfan could be removed at both 16-mg/min ozone dosages and pH = 4 for 60 minutes of ozonation. The order of the reaction is determined as pseudo first order. Although the rate of reaction was lower than other pesticide oxidation rates cited in the literature, β-endosulfan reaction to ozonation was achieved with almost 90% removal rate. The temperature dependent rate constant for β-endosulfan oxidation was determined as kd = 0.947 exp(-2.16 × 10-3/T).

A kinetic standard for precise calibration of spectrophotometer cell temperature.

1981 ◽  
Vol 27 (5) ◽  
pp. 753-755 ◽  
Author(s):  
P A Adams ◽  
M C Berman
Keyword(s):  
Temperature Dependence ◽  
Rate Constants ◽  
Cell Temperature ◽  
First Order ◽  
Order Rate ◽  
Acid Catalyzed ◽  
Pseudo First Order ◽  
Hydrolysis Of

Abstract We describe a simple, highly reproducible kinetic technique for precisely measuring temperature in spectrophotometric systems having reaction cells that are inaccessible to conventional temperature probes. The method is based on the temperature dependence of pseudo-first-order rate constants for the acid-catalyzed hydrolysis of N-o-tolyl-D-glucosylamine. Temperatures of reaction cuvette contents are measured with a precision of +/- 0.05 degrees C (1 SD).

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