Pulse Рhotochemical Decomposition of Phenol in Wastewater

Photochemical decomposition of phenol with a concentration of 5 to 24 mg/L using hydrogen peroxide and ultraviolet irradiation (UV/H2O2) was studied. Xenon flash lamp was chosen as a radiation source. It emits high-intensity continuous-spectrum radiation in a wide wavelength range from 200 to 1000 nm. The effect of the initial concentration of hydrogen peroxide and the source average radiation power on the phenol destruction rate were studied. An extremum in the dependence of the phenol decomposition rate constant on the initial concentration of hydrogen peroxide was found. Kinetic model of the process based on the obtained data was developed. It was tested by predicting phenol destruction rate with the different process parameters and gave good accuracy.

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Effect of Oxidant on the Leaching Rate of Indium from Water Quenching Slag

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.591.122 ◽

2013 ◽

Vol 591 ◽

pp. 122-125

Author(s):

Li Jiao Yang ◽

Si Chen ◽

Yan Zhang ◽

Nan Chun Chen ◽

Jun Gao ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Sulfuric Acid ◽

Potassium Permanganate ◽

Crystal Violet ◽

Acid Leaching ◽

Water Quenching ◽

Test Results ◽

Leaching Rate ◽

Initial Concentration ◽

Solid Ratio

Extracting indium from water quenching slag, which contains poor indium, by two process of leaching, the effect of different oxidants and dosages on the leaching rate of indium in water quenching slag were studied. The leaching conditions: temperature 80 °C, leaching time 2 h, the liquid to solid ratio of neutral leaching 8︰1, the liquid to solid ratio of acid leaching 2︰1, initial concentration of sulfuric acid 500 g·L-1, adding different oxidants, the concentration was detected by crystal violet spectrophotometry. Test results showed that the leaching rate of indium was significantly improved by adding hydrogen peroxide and potassium permanganate. Compared with the effect of different oxidants, the effect of potassium permanganate was significantly higher than that of hydrogen peroxide on the leaching rate of indium.

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Kinetics of the oxidation of diphenyl sulfide with hydrogen peroxide catalyzed by sodium metavanadate

Canadian Journal of Chemistry ◽

10.1139/v82-128 ◽

1982 ◽

Vol 60 (7) ◽

pp. 848-852 ◽

Cited By ~ 14

Author(s):

Yoshiro Ogata ◽

Kazushige Tanaka

Keyword(s):

Hydrogen Peroxide ◽

Rate Constant ◽

Reaction Rate ◽

Catalytic Amount ◽

Probable Mechanism ◽

Initial Concentration ◽

Sodium Metavanadate ◽

Low Concentration ◽

Diphenyl Sulfide ◽

Kinetics Of

The oxidation of diphenyl sulfide (Ph2S) by hydrogen peroxide in the presence of a catalytic amount of sodium metavanadate (NaVO3) has been studied kinetically by means of iodometry of hydrogen peroxide. The reaction rate is expressed as: v = k[NaVO3]st[Ph2S]2, when the concentration of catalyst is very low and [Ph2S]0/[H2O2]0 > 2, where []st and []0 mean stoichiometric and initial concentration, respectively. The effective oxidant may consist of polymeric as well as monomeric peroxyvanadate in view of the effect of concentration of catalyst on the rate. The main oxidizing species at low concentration of catalyst seems to be diperoxyvanadate VO5−. The rate constant k2 in v = k2[Ph2S]2 tends to decrease with initial concentration of H2O2, which is present in excess of the catalyst. A probable mechanism for the oxidation is discussed.

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The Photochemical Decomposition of Hydrogen Peroxide I

The Journal of Physical Chemistry ◽

10.1021/j150146a006 ◽

1914 ◽

Vol 18 (2) ◽

pp. 166-178 ◽

Cited By ~ 8

Author(s):

J. Howard Mathews ◽

Harry A. Curtis

Keyword(s):

Hydrogen Peroxide ◽

Photochemical Decomposition

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Decontamination of Dichlorvos by Hydrogen Peroxide

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.781-784.59 ◽

2013 ◽

Vol 781-784 ◽

pp. 59-62 ◽

Cited By ~ 1

Author(s):

Zhan Guo Li ◽

Wei Qin Wang ◽

Hai Ling Xi ◽

Hong Jie Zhao

Keyword(s):

Hydrogen Peroxide ◽

Oxidation Products ◽

Trimethyl Phosphate ◽

Chain Reaction ◽

Radical Chain ◽

Initial Concentration ◽

Dimethyl Phosphite ◽

Dimethyl Phosphate ◽

Methyl Phosphate ◽

Radical Chain Reaction

H2O2 aerosol was used to oxidize dichlorvos vapor. 80.7% of dichlorvos, with the initial concentration of 90.9 mg/m3, was decontaminated when the H2O2 concentration kept in the range of 110~130 mg/m3 within 60 min. According to the oxidation products, analyzed by GC-MS, the decontamination reaction mechanism was discussed. Radical chain reaction is the main decontamination mechanism. H2O2 is dissociated to HOO-, which can induce the formation of ·OH. The double bond in dichlorvos molecule is attacked by ·OH to form molecule radical, which is further oxidized to 1,1-dichloro ethoxy dimethyl phosphate, 1,1,1-trichloro-2-hydroxyl-ethyl dimethyl phosphate, dimethyl phosphite, dimethyl phosphate, trimethyl phosphate, methyl phosphate, dichloro acetaldehyde, oxalic acid, CH2Cl2, CHCl3, parts of which are mineralized to phosphoric acid, CO2, H2O and chloridion.

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Dairy Farming Simulated Organic Wastewater of Degradation Experiment by Hydrogen Peroxide

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1015.729 ◽

2014 ◽

Vol 1015 ◽

pp. 729-732

Author(s):

Yong Guang Bi ◽

Kuan Xin Zhang

Keyword(s):

Hydrogen Peroxide ◽

Organic Pollutants ◽

Degradation Rate ◽

Treatment Method ◽

Dairy Farming ◽

Initial Concentration ◽

Hydrogen Peroxide Treatment ◽

Simulated Wastewater ◽

Organic Wastewater

In dairy farming simulated wastewater resorcinol as the research object, using hydrogen peroxide treatment method to study the effect of resorcinol, the results showed that: when the initial concentration of hydroquinone 1.0g / L, 1.5g / L, 2.0g / L, 2.5g / L, 3.0g / L, the degradation rate was: 45.95%, 44.72%, 40.86%, 35.37%, 31.23%. Resorcinol degradation rate increases with the decrease of the initial concentration, that is beneficial to the low initial concentration of degradation, but the higher the initial concentration of the degradation rate. When the amount of hydrogen peroxide is 1mL, 1.5mL, 2mL, 2.5mL, when 3mL, the degradation rate was: 60.40%, 63.54%, 68.13%, 75.87%, 80.94%. Studies have shown that ultrasound combined with hydrogen peroxide is a good resorcinol degradation of organic pollutants in new ways.

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Simultaneous degradation of nitrogenous heterocyclic compounds by catalytic wet-peroxidation process using box-behnken design

Environmental Engineering Research ◽

10.4491/eer.2019.159 ◽

2019 ◽

Vol 25 (4) ◽

pp. 488-497

Author(s):

Vijayalakshmi Gosu ◽

Shivali Arora ◽

Verraboina Subbaramaiah

Keyword(s):

Hydrogen Peroxide ◽

Process Parameters ◽

Heterocyclic Compounds ◽

Optimization Technique ◽

Process Condition ◽

Quadratic Model ◽

Box Behnken Design ◽

Initial Concentration ◽

Toc Removal ◽

Initial Ph

The present study investigates the feasibility of nitrogenous heterocyclic compounds (NHCs) (Pyridine-Quinoline) degradation by catalytic wet peroxidation (CWPO) in the presence of nanoscale zerovalent iron supported on granular activated carbon (nFe0/GAC) using statistical optimization technique. Response surface methodology (RSM) in combination with Box-Behnken design (BBD) was used to optimize the process parameters of CWPO process such as initial pH, catalyst dose, hydrogen peroxide dose, initial concentration of pyridine (Py) and quinolone (Qn) were chosen as the main variables, and total organic carbon (TOC) removal and total Fe leaching were selected as the investigated response. The optimization of process parameters by desirability function showed the ~85% of TOC removal with process condition of initial solution pH 3.5, catalyst dose of 0.55 g/L, hydrogen peroxide concentration of 0.34 mmol, initial concentration of Py 200 mg/L and initial concentration of Qn 200 mg/L. Further, for TOC removal the analysis of variance results of the RSM revealed that all parameter i.e. initial pH, catalyst dose, hydrogen peroxide dose, initial concentration of Py and initial concentration of Qn were highly significant according to the p values (p < 0.05). The quadratic model was found to be the best fit for experimental data. The present study revealed that BBD was reliable and effective for the determination of the optimum conditions for CWPO of NHCs (Py-Qn).

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DELIGNIFICATION OF FLAX SHIVE

chemistry of plant raw material ◽

10.14258/jcprm.2018012757 ◽

2017 ◽

pp. 155-162 ◽

Cited By ~ 1

Author(s):

Наталья (Natal'ja) Викторовна (Viktorovna) Каретникова (Karetnikova) ◽

Лариса (Larisa) Валерьевна (Valer'evna) Чендылова (Chendylova) ◽

Роберт (Robert) Зусьевич (Zus'evich) Пен (Pen)

Keyword(s):

Hydrogen Peroxide ◽

Catalyst Concentration ◽

Sodium Tungstate ◽

Heat Insulation ◽

Hot Water ◽

Pulp Yield ◽

Complex Catalyst ◽

Initial Concentration ◽

Mass Part ◽

Catalyst Composition

Delignification of the flax shive (wastes of oakum and heat insulation production) was studied. Chemical composition of the work material (mass parts in percents from the bone-dry material): cellulose 30,7, lignin 33,1, pentosans 28,0, extractable by organic solvent 4,3, extractable by hot water 5,4, ash 1,7. The flax shive was delignificated in laboratory condition by means of peracetic acid, hydrogen peroxide and sulfate cooking solution. The conditions of peracetic pulping: initial mass part of the «icy» acetic acid in cooking solution 0,65, perhydrol 0,35, the catalyst concentration (sodium tungstate) 0,03 g-mol/dm3, liquid module 6, temperature 92 °C; pulp yield 46,1% without of undercooked pulp. The conditions of peroxide pulping: initial concentration of hydrogen peroxide 17%, liquid module 6, complex catalyst concentration 0,1 g-mol/dm3 (molar parts of the Na2WO4, Na2MoO4 and H2SO4 in catalyst composition are 0,3 : 0,3 : 0,4 accordingly), temperature 98 °C; pulp yield 45,8% without undercooked pulp. The conditions of sulfate pulping: initial concentration of active alkali 55 g/dm3 (in Na2O unit), degree of sulfidity 18%, liquid module 4, temperature 170 °C; pulp yield 32,3% without undercooked pulp. Samples of the technical cellulose, received by oxidizing methods, excel sulphate cellulose in relation to yield, ability for milling, whiteness and mechanical properties (except for tear). On the set of normalized properties they approach to characteristic of kraft bleached pulp from deciduous woods and can be considered as perspective stringy half-finished for production of the paper sanitary-household and hygienic purpose.

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Comparison of Azithromycin Removal from Water Using UV Radiation, Fe (VI) Oxidation Process and ZnO Nanoparticles

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17051758 ◽

2020 ◽

Vol 17 (5) ◽

pp. 1758

Author(s):

Amirreza Talaiekhozani ◽

Sahar Joudaki ◽

Farhad Banisharif ◽

Zeinab Eskandari ◽

Jinwoo Cho ◽

...

Keyword(s):

Uv Radiation ◽

Zno Nanoparticles ◽

Retention Time ◽

Langmuir Isotherm ◽

Hydraulic Retention Time ◽

Oxidation Process ◽

Radiation Power ◽

Biological Processes ◽

Optimal Conditions ◽

Initial Concentration

Antibiotics are resistant to biodegradation, and their removal by biological processes is difficult. The purpose of this study was to investigate the removal of azithromycin from water using ultraviolet radiation (UV), Fe (VI) oxidation process and ZnO nanoparticles. The effect of different parameters such as pH, temperature, hydraulic retention time (HRT), the concentration of Fe (VI) and ZnO nanoparticles and UV intensity on the removal of azithromycin from water was investigated. The optimal conditions for the removal of azithromycin were a pH of 2, a temperature of 25 °C, a HRT of 15 min, and a ratio of ZnO nanoparticles to the initial concentration of azithromycin (A/P) of 0.00009 which was fitted by Langmuir isotherm. In addition, the optimal conditions for the removal of azithromycin using UV radiation were a pH of 7, a temperature of 65 °C, a HRT of 60 min, and UV radiation power of 163 mW/cm2. For the Fe (VI) oxidation process, the optimal conditions were a pH of 2, a temperature of 50 °C and a HRT of 20 min. Also, the optimal ratio of Fe (VI) to the initial concentration of antibiotic was between 0.011 and 0.012. The results of this study showed that the Fe (VI) oxidation process, UV radiation, and ZnO nanoparticles were efficient methods for the removal of azithromycin from water.

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Photochemical decomposition of hydrogen peroxide (H2O2) and formaldehyde (HCHO) in artificial snow

Annals of Glaciology ◽

10.3189/172756404781814357 ◽

2004 ◽

Vol 39 ◽

pp. 29-33 ◽

Cited By ~ 11

Author(s):

Hans-Werner Jacobi ◽

Bright Kwakye-Awuah ◽

Otto Schrems

Keyword(s):

Hydrogen Peroxide ◽

Ice Cores ◽

Photochemical Activity ◽

Photochemical Reactions ◽

Visible Range ◽

Surface Snow ◽

Photochemical Decomposition ◽

Reactive Radicals ◽

Natural Snow ◽

Atmospheric Concentrations

AbstractLaboratory-made snow doped with either hydrogen peroxide (H2O2) or formaldehyde (HCHO) was exposed to radiation in the ultraviolet and visible range, resulting in a decomposition of both compounds. These experiments demonstrate that, besides the photolysis of nitrate, further photochemical reactions of atmospheric relevant compounds can take place in snow. Under similar conditions the decomposition of H2O2 is more efficient than that of HCHO. Since the decompositions in the experiments follow first-order reaction kinetics, we suggest that the same products as in photolysis reactions in the liquid phase are produced. If similar reactions also take place in natural snow covers, these reactions would have several important consequences. The reactions could represent pathways for the generation of highly reactive radicals in the condensed phase, enhancing the photochemical activity of surface snow and modifying the oxidation capacity of the atmospheric boundary layer. The photolysis could also constitute an additional sink for H2O2 and HCHO in surface snow, which should be taken into account for the reconstruction of atmospheric concentrations of both compounds from concentration profiles in surface snow and ice cores.

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