Factors Determining the Removal Efficiency of Procion MX in Waters Using Titanate Nanotubes Catalyzed by UV Irradiation

Vo Nguyen Xuan Que,Ta Thi Minh Dung,Dao Thi Thanh Binh,Nguyen Thi Thuy,Nguyen Nhat Huy,Tran Tien Khoi,Sumit Beniwal

doi:10.1155/2021/8870453

Abstract

The treatment of wastewater from the textile industry containing organic dyes faces many challenges since these compounds resist the biodegradation process in conventional treatment units. Among the physicochemical processes, photocatalysis is considered a facile, cheap, and environmental-friendly technology for treating persistent organic pollutants in waters at low concentrations. This study investigated several physicochemical factors determining the photocatalytic activity of titanate nanotubes (TNTs) to remove Procion MX 032 (PMX), an azo dye, in waters. Degradation of PMX by photocatalytic oxidation process at room temperature (30°C) was set up with the UV irradiation in the presence of different types of photocatalyst such as ST-01 (100% anatase), industrial TiO2, TNTs calcined at 120°C and 500°C. Effect of reaction time, catalyst amount, pH, light wavelength and intensity, and oxidants was investigated. Consequently, TNTs calcined at 500°C provided the highest removal efficiency. The photocatalytic oxidation of PMX by TNT calcined at 500°C was affected by pH variation, getting the highest removal at pH of 8, and inhibited with the presence of H2O2 and O2. Particularly, the PMX degradation using titanate nanotubes was optimized under the UV-A intensity of 100 W/m2. The dye was degraded by more than 95% at the TNTs concentration of 75 mg/L and pH 8.0 after 90 min. The results suggest that photocatalysis using TNTs can be a simple but efficient treatment method to remove PMX and potentially be applied for the treatment of wastewaters containing dyes.

Highlights

Textile industries produce a large amount of wastewater which contains a high concentration of inorganic salts and different types of reactive dyes for coloring clothes [1, 2].ese reactive dyes cause aesthetic problems, an increase of chemical oxygen demand of the wastewater [3]. ey may result in inhibition, eutrophication, and perturbation of the ecosystem because of their toxic and mutagenic effect [4], even at low concentrations [5], that should be removed from wastewater before discharging into the water environment
Several types of Procion MX were selected as the color target in wastewater treatment, such as Procion Red MX-5B [3], Procion Red MX 3B [7], Procion Blue MX-R [8], and Procion Brown MX-5BR [9], but the treatment wastewater containing Procion MX 032 has been rarely found except one report from Nguyen et al [10]
Fenton and Fenton-like reactions are usually applied for high strength wastewater due to its high cost of chemicals (Fe(II), persulfate, and H2O2) or electricity. erefore, photocatalysis, a destruction technique, is considered a promising technology to remove the low concentration of pollutants from aqueous phase systems for water purification and hazardous waste remediation [13], for the advanced treatment of textile wastewater after biological processes

Summary

Research Article

Vo Nguyen Xuan Que, Tran Tien Khoi, Nguyen Thi Thuy ,2,3 Ta Thi Minh Dung, Dao Thi Thanh Binh, and Nguyen Nhat Huy 1,2. Is study investigated several physicochemical factors determining the photocatalytic activity of titanate nanotubes (TNTs) to remove Procion MX 032 (PMX), an azo dye, in waters. Degradation of PMX by photocatalytic oxidation process at room temperature (30°C) was set up with the UV irradiation in the presence of different types of photocatalyst such as ST-01 (100% anatase), industrial TiO2, TNTs calcined at 120°C and 500°C. E photocatalytic oxidation of PMX by TNT calcined at 500°C was affected by pH variation, getting the highest removal at pH of 8, and inhibited with the presence of H2O2 and O2. E results suggest that photocatalysis using TNTs can be a simple but efficient treatment method to remove PMX and potentially be applied for the treatment of wastewaters containing dyes The PMX degradation using titanate nanotubes was optimized under the UV-A intensity of 100 W/m2. e dye was degraded by more than 95% at the TNTs concentration of 75 mg/L and pH 8.0 after 90 min. e results suggest that photocatalysis using TNTs can be a simple but efficient treatment method to remove PMX and potentially be applied for the treatment of wastewaters containing dyes

Introduction

Materials and Methods

Results and Discussion

Nanotubes Nanorods

Removal efficiency Removal capacity

Solution pH