Photocatalytic Degradation of p-Cresol by Zinc Oxide under UV Irradiation

Abstract

Photocatalytic degradation of p-cresol was carried out using ZnO under UV irradiation. The amount of photocatalyst, concentration of p-cresol and pH were studied as variables. The residual concentration and mineralization of p-cresol was monitored using a UV-visible spectrophotometer and total organic carbon (TOC) analyzer, respectively. The intermediates were detected by ultra high pressure liquid chromatography (UPLC). The highest photodegradation of p-cresol was observed at 2.5 g/L of ZnO and 100 ppm of p-cresol. P-cresol photocatalytic degradation was favorable in the pH range of 6–9. The detected intermediates were 4-hydroxy-benzaldehyde and 4-methyl-1,2-benzodiol. TOC studies show that 93% of total organic carbon was removed from solution during irradiation time. Reusability shows no significant reduction in photocatalytic performance in photodegrading p-cresol.

Photo-Decolourization Kinetics of Acid Red 87 Dye in ZnO Suspension Under Different Types of UV-A Light

“…• then leads hydroxyl radical HO • as powers force for starting a photo reaction as in equations from 18-25 [39][40][41].…”

Optical Photocatalytic Degradation of Methylene Blue Using Lignocellulose Modified TiO<sub>2</sub>

“…To detect changes in concentration, aliquots of methylene blue solution (5 mL) were taken after every 30 minutes and centrifuged followed by measuring the absorbance of the clean solution by UV-Vis spectrometer [23]. The concentration of MB was proportional to its absorbance according to Beer-Lambert law, so the degradation efficiency of organic compound (MB) was calculated as formula [24]:…”

Effect of Mn doping on structural, optical and photocatalytic behaviors of hydrothermal Zn1−xMnxS nanocrystals

“…RhB degradation was monitored from the decrease in intensity of its characteristic broad absorption at 557 nm. The photodegradation efficiency was calculated from [10][11][12]:…”