Photodegradation Of Paracetamol Research Articles

Bio-Mediated Synthesis of ZnO Nano Photocatalyst using C. gigantea (L.): Microstructural Study for Rapid Degradation of Organic Pollutants from Aqueous Medium

The purpose of this paper was to synthesize ZnO nanoparticles (NPs) from Calotropis gigantea (L.) and use them as photocatalyst for the elimination of wastewater contaminants, methyl orange (MO), and paracetamol (PCM) by UV irradiation. The UV-Vis absorption spectra show a peak at a wavelength of 374 nm with excitonic band gap of 3.41 eV. The hexagonal unit cell with mean crystallite size of 29.13 nm was found from the XRD pattern. The FESEM images confirms the formation of nanostructures. The bio-mediated nanoparticles are used as nano photocatalysts to eliminate MO and PCM. The effects of irradiation time, photocatalyst dose, dye concentration, and solution pH on photodegradation were studied in MO. Furthermore, the photodegradation of paracetamol was also investigated.

Photocatalytic Degradation of Paracetamol in Aqueous Medium Using TiO2 Prepared by the Sol-Gel Method.

Two titania photocatalysts have been prepared using the sol–gel method using TiCl4 as a precursor, and two different alcohols, namely, ethanol or propanol (Et or Pr). The main aim of this work was to study the effect of the nature of the alcohol on the chemical, structural and photocatalytic properties for paracetamol photodegradation of the final solids. The TiCl4/alcohol molar ratio to obtain the corresponding alkoxides (TiEt and TiPr) was 1/10. These alkoxides were calcined at 400 °C to prepare the oxide catalysts (named as TiEt400 and TiPr400). Powder X-ray diffraction (PXRD) of the original samples showed the presence of anatase diffraction peaks in sample TiPr, while TiEt is a completely amorphous material. Contrary to commercial TiO2-P25, the PXRD diagrams of the calcined samples showed anatase as the exclusive crystalline phase in both solids. The specific surface area (SBET) of sample TiPr400 was larger than that of sample TiEt400, and both larger than that of TiO2-P25. The three solids have been tested in the photodegradation of paracetamol in aqueous solution. It has been established that the alcohol used influences the properties and catalytic activity of the final oxides. The synthesized solids exhibit a higher activity than commercial TiO2-P25, because of their structural characteristics and larger SBET.

Excellent visible-light-driven Ni-ZnS/g-C3N4 photocatalyst for enhanced pollutants degradation performance: Insight into the photocatalytic mechanism and adsorption isotherm

In this paper, a series of nanocomposites consisting of different weight percentages of nickel-doped ZnS (Ni-ZnS)/graphitic-C3N4 (g-C3N4) have been synthesized via solid-state calcination of a mixture of pure g-C3N4 and 10 mol% Ni-ZnS. The proposed solid-state method is simple and provides a general route to make composite photocatalysts on a large scale. The shift in XRD peaks to lower theta value validates Ni+2 ion could be introduced effectually into the lattice of ZnS and substitutes to Zn+2 site. The interaction between Ni-ZnS and g-C3N4 in composite materials leads to long-lived charge carriers and efficient visible-light harvesting property. Which in turn showed remarkable high activity for degradation of RhB (92%, in 75 min), MB (96%, in 40 min) and paracetamol (86%, in 100 min), respectively. The photo mineralization of RhB, MB and paracetamol, over the most active 10 wt% Ni-ZnS/g-C3N4 nanocomposite was also evaluated by monitoring the reduction in TOC (total organic carbon) contents with respect to time under the visible light source. High-performance liquid chromatography results showed that no toxic by-products were formed during the photodegradation of paracetamol. On the basis of obtained results, a conceivable electron transfer mechanism has been stretched out for separating charge carriers and emphasizes the importance of superoxide and hydroxyl radicals for the degradation of pollutants in wastewater.

Photochemical synthesis of Ag/Au/AgCl heterostructure from Ag nanowires as a reusable SERS substrate for ultrasensitive detection of analgesics and antibiotics

The composite nanostructure composed of semiconductors and noble-metals have received widespread attention in the field of surface-enhanced Raman scattering (SERS). Herein, one-dimensional (1D) silver/gold/silver-chloride nanowires (Ag/Au/AgCl NWs) are prepared using the facile hydrothermal and photoreduction processes for the SERS detection of antibiotics and analgesics. The nanometer-scale interparticle gaps in the Ag/Au/AgCl heterostructure have been produced and the hotspots are provoked to enhance the SERS signal of target molecules by boosting the synergistic action of the heterostructure. The Ag/Au/AgCl heterostructure offers high sensitivity, good uniformity and high reproducibility. Meanwhile, the SERS substrate based on the Ag/Au/AgCl heterostructure is studied for the determination of paracetamol (PCT) and furazolidone (FZD) with the wide linear ranges of 10-1 M ~ 10-10 M and 10-1 M ~ 10-9 M. Their corresponding limits of detection (LOD) are as low as 2.8 × 10-12 M and 1.9 × 10-11 M, respectively. The separate and multiplex detection of PCT and FZD by the Ag/Au/AgCl heterostructure have been performed. Furthermore, the Ag/Au/AgCl heterostructure is successfully applied to determine the PCT and the FZD in the human urine samples with satisfactory results. To ensure the self-reviving ability of Ag/Au/AgCl heterostructure, the photodegradation of PCT and FZD molecules has been conducted and analyzed. The SERS substrate based on the semiconductor/noble-metal heterostructure with the self-reviving capability paves the way for the accurate detection of biologically important molecules like antibiotics and analgesics at the ultralow-level concentrations.

Interfacial Growth of Activated Carbon on WO3 Nanoplates for Enhanced Photocatalytic Activity by Surface Plasmon Resonance

A highly efficient, visible-light-driven and hybrid-activated carbon-doped pure tungsten trioxide (WO3) composite photocatalyst, with greatest stability has been synthesized by using hydrothermal method. Carbon nanoparticles were prepared by using sugarcane bagasse, and tungsten trioxide was prepared by using sodium tungstate (Na2WO4·2H2O) as a starting material. This study considers the photo-degradation of paracetamol by photocatalysis process, under visible-light irradiation. To study the properties of the prepared materials, SEM, TEM, FTIR, PL, and UV were performed. SEM was used to find the structure and size of the prepared materials. FTIR was used to analyze the presence of functional groups in the material. PL and UV were used to analyze the optical properties of the prepared materials. The SEM images of the prepared sample of WO3 showed that it has structure-like nanocubic and rectangular rods which become sharper by addition of carbon nanoparticles. The average size of the nanorods was about 50–550 nm. Some of the nanorods have smaller sizes about 25–250 nm which became beneficial for the photo-degradation process. UV–Vis spectroscopy showed that the band gap of the prepared samples varied from 2.78 to 2.26 eV, and this variation of the band gap was due to the variation in the concentration of the carbon nanoparticles. PL-spectroscopy analyzed the excitation wavelength of the prepared sample which was 448 nm. The efficiency of the prepared samples was evaluated by using paracetamol as target pollutant; carbon-doped composites of WO3 showed a greater photocatalytic performance as compared with the pure WO3. From the results of the photocatalytic activity, it was clear that composite having 2% carbon has the highest efficiency to degrade the paracetamol.

Photodegradation of Paracetamol using Electrosynthesized Silver Supported on Durio Zibethinus Husk

An advanced oxidation process (AOPs) using heterogeneous semiconductor photocatalysts such as TiO2, ZnO, CuO, and ZrO2 have become a popular method for the removal of toxic pollutants from wastewater. Recently, the noble metal nanoparticles (NPs), such as silver (Ag), gold (Au) and platinum (Pt) has also been intensively studied and show the intense UV and visible light absorbance capability. However, the usage of pure noble metal might be limited due to its cost, hence the utilization of support material is needed. Herein in this study, a simple electrochemical method was used to prepare a series of Ag (5, 10 and 15 wt%) loaded onto Durio Zibethinus Husk (Ag/DZH) as support material. The synthesized catalyst was examined using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), and Scanning Electron Microscopy (SEM) to measure the crystallinity, chemical composition and morphology, respectively. Additionally, the effect of Ag loading on DZH catalysts was evaluated through photocatalytic reaction to degrade 5 mg/L of pH 9 paracetamol in aqueous solution using 0.03 g/L catalyst. Among the catalysts, 10 wt% Ag/DZH shows the highest degradation rate of 0.01197 mg/L.min due to its size, well distribution as well as metal-support interaction.

PHOTOCATALYTIC REDUCTION OF Cu(II) ION AND TiO2-CATALYZED PARACETAMOL PHOTODEGRADATION AS AN ALTERNATIVE METHOD IN WASTE TREATMENT

<p>Recently, the issue of heavy metals are wastes is become popular such as Cu, Co, Pb, and etc. Furthermore, the presence of Cu together with paracetamol as pharmacy waste. Photocatalytic process could be an alternative to avoid the situation. This research investigated the influence of irradiation and the initial concentration of paracetamol toward TiO<sub>2</sub>-catalyzed photoreduction of Cu(II). The research aims to develop a photoreduction method that is catalyzed by TiO<sub>2</sub> in the presence of paracetamol in reducing Cu(II) and paracetamol concentration. Cu(II) photoreduction process was (II) conducted in a close reactor equipped with a UV lamp. The remaining Cu(II) in solution was analyzed using Atomic Absorption Spectrophotometry (AAS) to determine its concentration and paracetamol concentration by visible spectrophotometry method. Results showed that the use of photocatalyst TiO<sub>2</sub>improves the photoreduction of Cu(II), 15-45 minutes irradiation also contributes the increment, over the time a tiny decrease in photoreduction effectivity occur, however. At initial paracetamol concentration, 50 to 250 mg/L lead to an increase in photodegradation of paracetamol, and large decline occur over e.i. 250 mg/L, however. The presence of paracetamol may increase the effectiveness of Cu(II) photoreduction due to the prevention of radical OH<sup>•</sup> and electrons recombination. The most effective photoreduction of 25 mL solution of ion Cu(II) 10 mg/L is readily achieve in reaction conditions using 20 mg of TiO<sub>2</sub> by 45 minutes irradiation in the present of 25 mL of paracetamol 250 mg/L. By those Cu(II) ion was reduced by 98.87 % and 14.73 % of paracetamol was degraded.</p>

PHOTOCATALYTIC REDUCTION OF Cu(II) ION AND TiO2-CATALYZED PARACETAMOL PHOTODEGRADATION AS AN ALTERNATIVE METHOD IN WASTE TREATMENT

<p>Recently, the issue of heavy metals are wastes is become popular such as Cu, Co, Pb, and etc. Furthermore, the presence of Cu together with paracetamol as pharmacy waste. Photocatalytic process could be an alternative to avoid the situation. This research investigated the influence of irradiation and the initial concentration of paracetamol toward TiO<sub>2</sub>-catalyzed photoreduction of Cu(II). The research aims to develop a photoreduction method that is catalyzed by TiO<sub>2</sub> in the presence of paracetamol in reducing Cu(II) and paracetamol concentration. Cu(II) photoreduction process was (II) conducted in a close reactor equipped with a UV lamp. The remaining Cu(II) in solution was analyzed using Atomic Absorption Spectrophotometry (AAS) to determine its concentration and paracetamol concentration by visible spectrophotometry method. Results showed that the use of photocatalyst TiO<sub>2</sub>improves the photoreduction of Cu(II), 15-45 minutes irradiation also contributes the increment, over the time a tiny decrease in photoreduction effectivity occur, however. At initial paracetamol concentration, 50 to 250 mg/L lead to an increase in photodegradation of paracetamol, and large decline occur over e.i. 250 mg/L, however. The presence of paracetamol may increase the effectiveness of Cu(II) photoreduction due to the prevention of radical OH<sup>•</sup> and electrons recombination. The most effective photoreduction of 25 mL solution of ion Cu(II) 10 mg/L is readily achieve in reaction conditions using 20 mg of TiO<sub>2</sub> by 45 minutes irradiation in the present of 25 mL of paracetamol 250 mg/L. By those Cu(II) ion was reduced by 98.87 % and 14.73 % of paracetamol was degraded.</p>

Heterogeneous photodegradation of paracetamol using Goethite/H 2 O 2 and Goethite/oxalic acid systems under artificial and natural light

Abstract Heterogeneous photodegradation of paracetamol (PC) in the α-FeOOH (Goethite) used as a catalyst was studied in aqueous suspension up on irradiation at 365 nm and by solar light. The mechanism involves PC-Goethite system operate electron–hole pairs. The rate of photocatalytic degradation of PC is slow and follows pseudo-first order kinetics. The addition of H 2 O 2 in the previous solution leads to OH radicals formation via the Fenton system. Goethite in the presence of oxalic acid can form Goethite–oxalate complex on the surface. So under irradiation the photo-reduction of Goethite–oxalate complexes yields Fe(II) and oxalate radicals (C 2 O 4 ) − , which induces the formation of active species ( OOH\O 2 − ) leading to the Fenton reaction. The effect of catalyst loading, initial concentration of PC, hydrogen peroxide (H 2 O 2 ) and oxalic acid concentrations were determined. The optimal initial concentration of hydrogen peroxide and oxalic acid for the PC degradation with Goethite under the experimental conditions was found to be 5 × 10 −3 and 5 × 10 −4 mol L −1 respectively. The photodegradation of PC in the mixtures PC–Goethite, PC–Goethite–H 2 O 2 and PC–Goethite–oxalic acid under solar light was significantly accelerated in comparison with artificial irradiation at 365 nm.

Photodegradation of paracetamol in montmorillonite KSF suspension

Photodegradation of paracetamol in montmorillonite KSF suspension followed the Langmuir–Hinshelwood kinetic model. The influence of KSF dosage, initial paracetamol concentration, initial pH, chelating agents and a radical scavenger on the degradation of paracetamol were studied and described in detail. The degradation mechanism of paracetamol was also proposed in this work.

Melatonin Alters the Photodegradation of Paracetamol

The effects of melatonin, a known free-radical scavenger, on paracetamol in the presence of UV irradiation was studied by use of HPLC. The experiments were performed in air and nitrogen. The results show that the rate of photodegradation of melatonin is faster in air than in nitrogen whereas that of paracetamol is similar in air and nitrogen. When the two drugs were combined, melatonin retarded the degradation of paracetamol for up to 6h in the presence of nitrogen. However, in the presence of air melatonin rapidly enhances the photodegradation of paracetamol. This study shows that a combination of melatonin and paracetamol in the presence of air and UV irradiation can lead to rapid inactivation of both agents, thus raising important concerns about the possible use of melatonin as sunscreen.