Mineralization of paracetamol in aqueous solution with advanced oxidation processes

Abstract

Paracetamol is a common analgesic drug widely used in all regions of the world more than hundred tonnes per year and it poses a great problem for the aquatic environment. Its phenolic intermediates are classified as persistent organic pollutants and toxic for the environment as well as human beings. In the present study, the irradiation of aqueous solutions of paracetamol with 60Co gamma-rays was examined on a laboratory scale and its degradation path was suggested with detected radiolysis products. The synergic effect of ozone on gamma-irradiation was investigated by preliminary ozonation before irradiation which reduced the irradiation dose from 5 to 3 kGy to completely remove paracetamol and its toxic intermediate hydroquinone from 6 to 4 kGy as well as increasing the radiation chemical yield (Gi values 1.36 and 1.66 in the absence and presence of ozone, respectively). The observed amount of formed hydroquinone was also decreased in the presence of ozone. There is a decrease in pH from 6.4 to 5.2 and dissolved oxygen consumed, which is up to 0.8 mg l(-1), to form some peroxyl radicals used for oxidation. Analytical measurements were carried out with gas chromatography/mass spectrometry and ion chromatography (IC) both qualitatively and quantitatively. Amounts of paracetamol and hydroquinone were measured with gas chromatography after trimethylsilane derivatization. Small aliphatic acids, such as acetic acid, formic acid and oxalic acid, were measured quantitatively with IC as well as inorganic ions (nitrite and nitrate) in which their yields increase with irradiation.

Paracetamol degradation in aqueous solution by non-thermal plasma

“…Fourthly, we detected nine other peaks, among which eight carboxylic acids; the m/z values and inferred compounds are listed in Table 2. These products have already been observed during paracetamol treatment performed by other AOPs [12,[15][16][17][18][19] and also in a process using NTP [3]. Moreover Marotta et al [20] already demonstrated the formation of carboxylic acids in their experiments concerning the treatment of phenol by a non-thermal plasma.…”

Organophosphate Esters Removal by Uv/H2 O2 Process Monitored by 31p Nuclear Magnetic Resonance Spectroscopy

“…This is an indication that TCEP is more resistant to HO• attack than TBEP and TBP. Some studies in the literature have also obtained similar results in the degradation of organic compounds using the UV/H 2 O 2 reaction and analysing by chromatographic analysis (Torun et al, 2015;Mohapatra et al, 2014). 31 P NMR signals of OPEs had chemical shifts less than those observed for inorganic phosphates due the C-O covalent bonds, which are not observed in inorganic phosphates.…”

“…2) (Litter, 1999). In some cases, the partial oxidation of organic pollutants may result in the formation of intermediates with higher toxicity than the parent compounds (Torun et al, 2015). (1)…”

Degradation of Diazepam with Gamma Radiation, High Frequency Ultrasound and UV Radiation Intensified with H2O2 and Fenton Reagent

“…In the alkaline medium, the dissociation of the HO • radical occurs, so degradation of the drug is not favored (Equations ( 8)-( 10)). Different authors report the same behavior in the radiolytic degradation of other drugs with increasing pH [35][36][37].…”