Performance improvement of the photocatalytic process for the degradation of pharmaceutical compounds using new POM/polymer photocatalysts

Abstract

In the last few years, pharmaceuticals compounds classified as emergent pollutants have attracted the attention of many researchers, due to their massive presence in soil, surface, sewage, groundwater and drinking water, and to their harmful impacts on human's health and environment. In this context, the degradation of four drugs with different chemicals structures which are Ciprofloxacin, Oxytetracyclin, Ibuprofen and Erythromycin was investigated. Indeed, in this paper, we studied the impact of the presence in the aqueous solution of a newly developed POM/polymer composites on the removal of these different drugs from water. Synthetic details and characterization of these materials were previously reported by our group. The different experiments done in this work revealed that the presence of the phosphomolybdic acid-based composite was not essential for the total degradation of Ciprofloxacin and Oxytetracyclin which could be totally removed from water by simple photolysis under UV lamp irradiation. However, under the same experimental conditions, the use of this photocatalyst was indispensable for the total mineralization of Ibuprofen which is more recalcitrant than the other chosen drugs. In fact, just 16% of this pharmaceutical was degraded by simple photolysis vs. 100% and 94% under 90 min. of UV lamp and solar irradiation, respectively in the presence of the phosphomolybdicacid-based composite which was more pertinent than the usually used photocatalyst, namely titanium dioxide. Ibuprofen degradation pathway was identified thanks to mass spectrometry analysis, carried out at different times intervals. The obtained results demonstrated also that POM/polymer composite inhibits the degradation of Erythromycin by provoking the formation of more toxic intermediates than the original drug.

Recent advances on photobleachable visible light photoinitiators of polymerization

“…Reproduced with permission of Ref. [48] In an effort to identify structures exhibiting this highly researched photobleaching property while being disconnected from the chemical structures of historical photoinitiators such as TPO or BAPO, a wide range of structures have been examined during the last decade, as exemplified with cyanines, [49][50][51][52][53][54][55] truxene derivatives, [56] viologen derivatives, [57][58][59] metal organic framework (MOFs), [60][61][62] conjugated polymers, [63] polyoxometalates, [64][65][66] Bodipy, [67][68][69] dithienophospholes, [70,71] perylenes, [72][73][74][75] iron complexes, [61,[76][77][78][79][80][81][82] 2,3diphenylquinoxaline derivatives, [83] diketopyrrolopyrroles, [84][85][86] chromones and flavones, [87][88][89] zinc complexes, [90] pyrrole derivatives,…”

Deep Eutectic Solvent-Assisted Synthesis of a Strontium Tungstate Bifunctional Catalyst: Investigation on the Electrocatalytic Determination and Photocatalytic Degradation of Acetaminophen and Metformin Drugs

“…Due to its minimal toxicity, economic stability of the photocatalyst, strong oxidizing tendency, and lack of hazardous byproducts, a semiconductor-based catalyst is the best candidate to mineralize the active components fully. 43 The reaction depends on irradiation source wavelengths, power, absorption spectra, and pollutant chemical structures. Thus, this work focuses on developing an ideal active catalyst that can detect and degrade pharmaceutical components in aquatic environments.…”

“…The selected pharmaceutical items require a bifunctional catalyst to degrade drug molecules completely. Due to its minimal toxicity, economic stability of the photocatalyst, strong oxidizing tendency, and lack of hazardous byproducts, a semiconductor-based catalyst is the best candidate to mineralize the active components fully . The reaction depends on irradiation source wavelengths, power, absorption spectra, and pollutant chemical structures.…”

Shifting from UV to Visible-Light the Activity of Organic Photoinitiators via the Covalent Grafting of Polyoxometalates

“…While the classical acid or alkali salts of POMs are generally highly soluble in water, limiting their recyclability and reusability in important applications such as catalysis, 6 this disadvantage can be overcome by incorporating them into matrices. For instance, the decatungstate polyanion [W 10 O 32 ] 4− and the seminal [PMo 12 O 40 ] 3− and [SiMo 12 O 40 ] 4− Keggin species, highly recognized for their catalytic properties, have been immobilized into polymers using photopolymerization techniques. In that way, [W 10 O 32 ] 4− POMs were associated with silanes (or borane derivatives) and iodonium salts to promote the free-radical cationic photopolymerization of epoxides under polychromatic Hg−Xe irradiation.…”