Degradation Of Phenazopyridine Research Articles

A solar-driven CPC photoreactor for decomposition of emerging contaminants in wastewater: Modeling and optimization

In the present work, a new component parabolic collector (CPC) was introduced as a solar photocatalytic reactor and applied in pilot-scale for degradation of Phenazopyridine (PhP) via a Solar/H2O2/S2O82-/TiO2 process. The TiO2 nanoparticles were immobilized on the outer surface of CPC receivers’ tubes by physicochemical processes. Field emission scanning electron microscopy (FESEM) was demonstrated a favorable attachment of nanoparticles on the glass tubes. Low Ti leaching during repeated experiments was approved by inductively coupled plasma (ICP) analysis. The final degrading by-products of PhP were identified and analyzed by gas chromatography-mass spectroscopy (GC-MS) analysis. Moreover, the impact of the effective parameters on the degradation of PhP during dual oxidation process in a solar-driven photocatalytic reactor such as flow rate, oxidant, PhP concentration, and pH was investigated and simulated with Artificial Neural Network (ANN) analysis and optimized with Genetic Algorithm (GA) and Ant Colony Algorithm (ACA). Consequently, the toxicity of effluent was tested with plants in optimal conditions when the oxidation step proceeded. This report summarized the current status of solar photocatalysis favorable photocatalytic activity under solar light irradiation enhanced with CPC photoreactor which was successfully prepared. Guided by studies to explore the determination of optimal conditions for disinfection of real municipal wastewater, the biological treatment was investigated. In addition, the antibacterial assessment was considered to determine the presence of bacteria after solar disinfection.

High performance ozone based advanced oxidation processes catalyzed with novel argon plasma treated iron oxyhydroxide hydrate for phenazopyridine degradation

The present study has focused on the degradation of phenazopyridine (PhP) as an emerging contaminant through catalytic ozonation by novel plasma treated natural limonite (FeOOH·xH2O, NL) under argon atmosphere (PTL/Ar). The physical and chemical characteristics of samples were evaluated with different analyses. The obtained results demonstrated higher surface area for PTL/Ar and negligible change in crystal structure, compared to NL. It was found that the synergistic effect between ozone and PTL/Ar nanocatalyst was led to highest PhP degradation efficiency. The kinetic study confirmed the pseudo-first-order reaction for the PhP degradation processes included adsorption, peroxone and ozonation, catalytic ozonation with NL and PTL/Ar. Long term application (6 cycles) confirmed the high stability of the PTL/Ar. Moreover, different organic and inorganic salts as well as the dissolved ozone concentration demonstrated the predominant role of hydroxyl radicals and superoxide radicals in PhP degradation by catalytic Ozonation using PTL/Ar. The main produced intermediates during PhP oxidation by PTL/Ar catalytic ozonation were identified using LC–(+ESI)–MS technique. Finally, the negligible iron leaching, higher mineralization rate, lower electrical energy consumption and excellent catalytic activity of PTL/Ar samples demonstrate the superior application of non-thermal plasma for treatment of NL.

Iron modified zeolite carrier for efficiently pharmaceutical pollutant degradation in heterogeneous electro‐Fenton: Influence factors and kinetic

AbstractIn this study, the high silica ZSM‐5 carrier was modified with the iron species and applied as a heterogeneous electro‐Fenton (EF) catalyst for pharmaceutical pollutant degradation. The carrier was prepared by the hydrothermal method and followed by impregnation. The physicochemical properties were evaluated by field emission scanning electron microscopes (FE‐SEM), FT‐IR, X‐Ray diffraction (XRD), and N2 adsorption–desorption techniques. The impregnated carrier had high crystallinity, high specific surface area, and uniform dispersion of iron species. The effect of different operating conditions was studied on the phenazopyridine (PHP) degradation efficiency. The optimal efficiency of PHP degradation (ca. 92.5%) was obtained at pH of 3.0, the current density of 100 mA, catalyst loading of 0.2 g L−1, and T = 25°C. The data of kinetic showed that the degradation of PHP followed Pseudo‐First‐Order kinetic, including the high accuracy (R2 > 0.95). The developed catalyst had the high stability and reusability for the PHP degradation in the EF process, while the degradation efficiency dropped only 0.5% for the regenerated catalyst.

The role of ruthenium photosensitizers in the degradation of phenazopyridine with TiO2 electrospun fibers

Abstract There has been increased interest in titanium dioxide (TiO2) fibers as a photocatalyst for the degradation of persistent organic and biopharmaceutical toxins in the environment. The photocatalytic efficiency of TiO2 fibers is typically limited to UV irradiation due to its semiconductor bandgap. TiO2 fibers have been prepared and adsorbed the visible photosensitizer cis-dichlorobis(2,2′-bipyridyl-4,4′-dicarboxylic acid)ruthenium (II) (Ru(dcbpyH2)2Cl2) on the surface in order to absorb from 300 to 800 nm in the visible spectrum and drive photocatalysis. This dye fiber material has been applied to the degradation of 2,6-pyridinediamine,3-(phenylazo) monohydrochloride or phenazopyridine (PAP) as a model biopharmaceutical waste. The Ru(dcbpyH2)2Cl2–sensitized fibers degrade PAP under UV and visible irradiation following a first order reaction rate. The rate constants for PAP degradation in visible light when using bare TiO2 fibers and dye-sensitized TiO2 fibers were 0.014 ± 0.001 min−1 and 0.012 ± 0.001 min−1 respectively, showing little change. Under UV irradiation, the rate decreased from 0.032 ± 0.003 min−1 and 0.012 ± 0.002 min−1. These results suggest that the major pathway for the degradation of PAP may occur through the valence band.