Removal of β-lactam antibiotics from pharmaceutical wastewaters using photo-Fenton process at near-neutral pH

Abstract

In this work, the photo-Fenton process at near-neutral pH was applied for the removal of the β-lactam antibiotic oxacillin (OXA) in water using artificial and sunlight. Initially, the main variables of the process (Fe(II), HO, and light power) were optimized by a statistical factorial design (2 with center points). The experimental design indicated that 90 μmol L of Fe(II), 10 mmol L of HO, and 30 W of power light were the favorable conditions for degradation of OXA at 203 μmol L. In the photo-Fenton system, the HO alone, UV-light/HO, and Fe(II)/HO subsystems presented a significant participation on antibiotic removal. Moreover, based on the primary organic transformation products, a mechanism of OXA degradation was proposed. Under the favorable operational conditions, both the pollutant and the antimicrobial activity were eliminated after 50 min of process application. Although at 480 min of treatment, only 5% of mineralization was achieved, the level of biodegradability of the solutions increased from 0.08 to 0.98. Interestingly, the presence of pharmaceutical additives (glucose, isopropanol, and oxalic acid) had a moderate interference on the efficiency of the pollutant removal. Additionally, the treatment at pilot scale of the β-lactam antibiotic in a pharmaceutical complex matrix using solar radiation allowed the complete removal of the pollutant and its associated antimicrobial activity in a very short time period (5 min). These results evidenced the applicability of the photo-Fenton process to treat wastewaters from pharmaceutical industry loaded with β-lactam antibiotics at near neutral pH values efficiently.

Understanding the Role of Complexation of Fluoroquinolone and β-Lactam Antibiotics with Iron (III) on the Photodegradation under Solar Light and UVC Light

“…Although several studies deal with the (photo)-degradation of fluoroquinolone and β-lactam antibiotics by systems involving iron [18,[21][22][23], there is little information about the effect of the complexation of these antibiotics by ferric ions, nor the implications of their photodegradation. Such works depict the degradation percentages of the antibiotic caused by the radical species action, but none quantify the interaction of ferric ions with the target pollutants and the role of complexation in the degradation.…”

Insights into the generation of hydroxyl radicals from H2O2 decomposition by the combination of Fe2+ and chloranilic acid

“…hui Zhang et al 2019;Oturan et al 2012;Oliveira et al 2014). This reaction was recognized by its great success and high efficiency to remove many organic and inorganic recalcitrant compounds from soil and water (Telles and Granhen Tavares 2012;Nidheesh et al 2013;Yue et al 2015;Martínez-Costa et al 2018;Giraldo-Aguirre et al 2018;Verma and Chaudhari 2020). This is due to the intensive oxidative power, short lifetime, and high reactivity of the ⋅ OH radicals (Cheng et al 2016;Buxton et al 1988;García et al 2013).…”

Enhanced catalytic degradation of amoxicillin with TiO2–Fe3O4 composites via a submerged magnetic separation membrane photocatalytic reactor (SMSMPR)

“…13,15 The photo-Fenton process is a typical combination of two kinds of advanced oxidation process (AOP) and shows high oxidative removal efficiency of organics because of the highly enhanced generation of reactive hydroxyl radicals ($OH). [16][17][18] However, one of the major drawbacks, separation and recycling of catalyst particles from large quantities of water, needs further cost and restrains the practical application of photocatalytic process. Accordingly, many studies were trying to explore an economic way to get the catalysts back.…”