Articolele autorului Mariana Neamtu
Link la profilul stiintific al lui Mariana Neamtu

Comparation of disperse red 354 azo dye degradation in water by several oxidation processes

The degradation of the Disperse Red 354 azo dye in water was investigated in laboratory- scale experiments, using four advanced oxidation processes (AOPs): ozonation, Fenton, UV/ H2O2, and photo-Fenton. The photodegradation experiments were carried out in a stirred batch photoreactor equipped with an immersed low-pressure mercury lamp as UV source. Besides the conventional parameters acute toxicity test with LUMIStox 300 instrument was conducted

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Abiotic treatment of drinking water:nitromusk destruction by ultraviolet oxidation with hydrogen peroxide(II)
Abiotic treatment of drinking water:nitromusk destruction by ultraviolet oxidation with hydrogen peroxide(I)
Comparasion of methods for COD determination in wastwwater streams

The objective of this work was a critical evaluation of analytical methods for the determination of the chemical oxygen demand (COD) in samples with elevated chloride concentrations. The precision and accuraca of test kits commercially available were compared with a German standards method. To avoid a basis in the COD determination, chloride concentrations were eliminated as gaseous chloride or by complexing agent.

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Kinetics of Bisphenol-A photodegradation in water by ultraviolet activated hydrogen peroxide

Aqueous solution containing 0.52 mmol/L bisphenol-A and various doses of hydrogen peroxide have been irradiated with a UV low-pressure mercury lamp immersed in a batch cylindrical photoreactor. The BPA concentrations and three main products (phenol, DHB, BQ) have been followed by HPLC with a Diode Array Detector. After 20 minutes of irradiation the conversion of BPA was only 16.54% with no H2O2 but as high as 98.13% with 0.49 mmol/L H2O2 added. Using

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Vergleich von Methoden zur CSB-Bestimmung in Abwasserteilströmen

Ziel der vorliegenden Arbeit war ein kritischer Vergleich der CSB-Bestimmung unter Anwendung des Küvettentests und nach DIN-Verfahren für Proben mit hohen Chloridionen-Konzentrationen. Unter hohen Chloridionen-Konzentrationen sind solche Konzentrationen zu verstehen, die besondere Maßnahmen zur Reduktion, bzw. -Maskierung der Chloridionen erforden.

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Photodegradation of Azo Dyes in Textile Wastewater

The photodegradation of three non hydrolysed reactive azo dyes (Reactive red 120, Reactive black 5, Reactive yellow 84) in aqueous solution was investigated in a laboratory-scale batch photoreactor equipped with an immersed lowpressure mercury lamp. Six different doses of hydrogen peroxide, at constant initial concentration of the substrate (100 mg/l) were used. The pseudo-first order rate constants have been calculated from the experimental kinetic

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Phodegradation of reactive yellow 84 azo-dye in aqueous solution

The photodegradation of the Reactive Yellow 84 azo-dye in ultrapure water is investigated in a laboratory-scale batch photoreactor equipped with an immersed low-pressure mercury lamp as UV source. The konetic results show that the UV/H2O2 process, with a H2O2 dose of 9.8 mmol/L, is 85 times faster than the UV process. After 60 minutes of irradiation, with 0.98 mmol/L H2O2, the decolorization is almost complete whereas the mineralization degree of

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Kinetics of Nitromusk Compounds Degradation in Water by Ultraviolet Radiation and Hydrogen Peroxide

The photodegradation of five representative nitromusk compounds in water has been performed in a stirred batch photoreactor with a UV low-pressure immersed mercury lamp, at constant temperature and different doses of hydrogen peroxide. The rate constants have been calculated on the basis of experimental data an a postulated first-order kinetic model. The rate constants, at 298K and a dose of 1.175 µmol/L H2O2 ranges from 0.357 x 10-3 s-1 for musk

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