Comparative overview of advanced oxidation processes and biological approaches for the removal pharmaceuticals

Advanced Oxidation Processes (AOPs) – Utilization of Hydroxyl Radical and Singlet Oxygen

“…[39] The mechanism of hydroxyl radical formation is understood as homolytic cleavage of hydrogen peroxide molecule yielding two radicals from one hydrogen peroxide molecule. On the contrary hydrogen peroxide has a small absorption coefficient (18.6 M À1 cm À1 at 254 nm) and consequently the utilization of UV-C light source is decreased when organic compounds act as optical filters 8 . The cage effect of water molecules also decreases the efficiency of hydroxyl radical generation.…”

“…AOPs were developed in order to oxidize organic compounds that can be resistant or which are able to deactivate traditionally used biological stage at sewage disposal plants (these compounds are non-biodegradable) including also pharmaceutical residues. [8,9] If the final results of chemical oxidation are just inorganic products, such as CO 2 ,H 2 O and other harmless inorganic compounds, we talk about complete mineralization or total oxidation. AOPs are employed to replace standard oxidation technologies, such as oxidation with KMnO 4 ,K 2 Cr 2 O 7 and Na 2 S 2 O 8 because they can oxidize many organic compounds only partially.…”

Recent Trends in Pharmaceuticals Removal from Water Using Electrochemical Oxidation Processes

“…In recent decades, the intense environmental contamination was mostly attributed to the rapid industrialization of the modern societies dictated by the increased human needs, raising serious concerns in the international scientific community [1,2]. Among the various wastes present in water bodies, pharmaceuticals (PhCs) hold a special place since their presence even at low concentrations can cause irreversible damage to the ecosystem and human health [3].…”

“…PhCs can be divided into various categories concerning their characteristics such as anti-inflammatory (e.g., diclofenac), antiepileptic (e.g., carbamazepine), stimulant (e.g., caffeine), β-blockers (e.g., propranolol), antibiotics (sulfamethoxazole), psychiatric (e.g., venlafaxine), antimicrobials (e.g., triclosan), etc. [1].…”

MoS2-assisted Fe2+/peroxymonosulfate oxidation for the abatement of phenacetin: efficiency, mechanisms and toxicity evaluation

“…Currently, advanced oxidation processes, abbreviated AOPs, have attracted increasing attention due to their successful application to decompose PPCPs in water by generating highly reactive radical species, i.e., hydroxyl radical (cOH). 6 More recently, sulfate radical (SO 4 c À )-based AOPs have gained popularity for the treatment of PPCPs in water owing to their comparable standard redox potential (E 0 ¼ 2.5-3.1 V) with that of cOH (E 0 ¼ 2.8 V). 7,8 In addition, SO 4 c À was more selective than cOH, making SO 4 c À -based AOPs less impacted by the presence of common inorganic anions and natural organic matter (NOM).…”