Selecting the best AOP for isoxazolyl penicillins degradation as a function of water characteristics: Effects of pH, chemical nature of additives and pollutant concentration

Abstract

a b s t r a c tTo provide new insights toward the selection of the most suitable AOP for isoxazolyl penicillins elimination, the degradation of dicloxacillin, a isoxazolyl penicillin model, was studied using different advanced oxidation processes (AOPs): ultrasound (US), photo-Fenton (UV/H 2 O 2 /Fe 2þ ) and TiO 2 photocatalysis (UV/TiO 2 ). Although all processes achieved total removal of the antibiotic and antimicrobial activity, and increased the biodegradability level of the solutions, significant differences concerning the mineralization extend, the pH of the solution, the pollutant concentration and the chemical nature of additives were found. UV/TiO 2 reached almost complete mineralization; while~10% mineralization was obtained for UV/H 2 O 2 /Fe 2þ and practically zero for US. Effect of initial pH, mineral natural water and the presence of organic (glucose, 2-propanol and oxalic acid) were then investigated. UV/H 2 O 2 /Fe 2þ and US processes were improved in acidic media, while natural pH favored UV/TiO 2 system. According to both the nature of the added organic compound and the process, inhibition, no effect or enhancement of the degradation rate was observed. The degradation in natural mineral water showed contrasting results according to the antibiotic concentration: US process was enhanced at low concentration of dicloxacillin followed by detrimental effects at high substrate concentrations. A contrary effect was observed during photo-Fenton, while UV/TiO 2 was inhibited in all of cases. Finally, a schema illustrating the enhancement or inhibiting effects of water matrix is proposed as a tool for selecting the best process for isoxazolyl penicillins degradation.

Facile Synthesis and Characterization of Ag3PO4 Microparticles for Degradation of Organic Dyestuffs under White-Light Light-Emitting-Diode Irradiation

“…Advanced oxidation processes (AOPs) have gained considerable attention for the treatment of organic dyestuffs polluted environmental water matrices [ 1 , 2 , 3 , 4 ]. Among the various AOPs, heterogeneous photocatalysis, which employs semiconductor-based photocatalysts, has been the subject of numerous studies on due to its ability to decompose organic compounds under solar light irradiation [ 5 , 6 , 7 , 8 , 9 ]. For example, the heterogeneous photocatalyst TiO 2 is considered an excellent material for water treatment because it is cheap, nontoxic and abundant in nature [ 5 , 6 , 10 , 11 ].…”

Elimination of cephalexin and doxycycline under low frequency ultrasound

“…From the figure, it can be appreciated that the extent of CPX and DOX elimination (C/C 0 ) is inversely proportional to the pollutant initial concentration. In this sense, organic pollutants removal using ultrasound irradiation can be described using a pseudo first-order reaction kinetic model (Equation (8) ) [39] , [40] , [41] . However, as it is shown by Fig.…”

Oxidative decolorization of a malachite green oxalate dye through the Photochemical Advanced Oxidation Processes

“…Experimental parameters are given in figure caption (Figure 3). From published literature data, it was observed that photochemical AOPs for remediation of aqueous water pollutant including organic dyes occurs at pH-3 (acidic) (Jamil et al, 2011;Villegas-Guzman et al, 2017). Solutions at pH 3 were prepared by drop wise addition of 0.1 N NaOH to dye solution until the desired pH was obtained.…”