Effects of KBr and KI on Photocatalytic Degradation of Dye W-7G with Nano-TiO2 as Catalyst

Chao Zou,Wen Zhong,Chen Jing,Jing-Tuo Zhu,Qi-Jin Geng,Zhao-Sheng Hou,Adel A Ismail

doi:10.1155/2021/6610093

Chao Zou, Wen Zhong + Show 5 more

Open Access

https://doi.org/10.1155/2021/6610093

Copy DOI

Abstract

To investigate the influence of inorganic salt on the photocatalytic degradation, the effects of KBr and KI at various concentrations and pH values on the photocatalytic degradation of dye W-7G using nanoscaled titanium dioxide as photocatalyst in a bubbling fluidized bed photocatalytic reactor (BFBPR) were studied. The results indicated that the degradation apparent rate constant ( K app ) of the system with KI was clearly higher than that with KBr under acidic or alkaline conditions. And the maximum value of K app (0.01127) appeared at the KI concentration of 0.075 g L-1 with a pH value of 9.37, meaning the highest degradation efficiency. Furthermore, the possible mechanism of photocatalytic degradation of W-7G in the presence of KBr and KI was proposed, which could provide a theoretical support for the further study of inorganic salt effects on the photocatalytic degradation of dyes.

Highlights

Because of the complex structure of most reactive dyes, there are many side reactions in the production process, so the rapid degradation of dye wastewater is urgently required
It could be deduced that the pH value had an impact on the photocatalytic degradation of W-7G and the photocatalytic degradation efficiency of TiO2 in acid medium was higher than that in alkaline medium
The effect of inorganic salt KBr and KI on the photocatalytic degradation of W-7G was investigated at different pH values using nano-TiO2 as photocatalyst

Summary

Introduction

Because of the complex structure of most reactive dyes, there are many side reactions in the production process, so the rapid degradation of dye wastewater is urgently required. The results showed that adding salt solution to the photocatalytic degradation system affected the degradation kinetics and mechanism of the system. The study of adding salt to the photocatalytic degradation system lacked systematic analysis, and there was no systematic correlation analysis between the degradation rate constant (Kapp) of photocatalytic degradation and the amount of inorganic salt added [9]. In this case, the effects of inorganic salts KBr and KI on the degradation kinetics of the reactive light-yellow dye of W-7G were studied in an annular coaxial doublecylinder-type reactor (BFBPR) using nano-TiO2 as a photocatalyst. According to the change trends of apparent constant curve of photocatalysis, the main reasons influencing the photocatalytic degradation were deduced, and the possible mechanism of photocatalytic degradation of salt was proposed

Experimental Section

Results and Discussion

Conclusions