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

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.

Treatment of textile dye wastewater by peroxymonosulfate activation using facilely prepared Fe3O4@TiO2 heterogeneous photocatalyst

“…The effect of operating factors on the treatment performance of the system was investigated using different material dosages (0.1-1 g L -1 ), PMS concentration (0.1-1 g L -1 ), RhB concentration (50-100 mg L -1 ), solution pH (3)(4)(5)(6)(7)(8)(9)(10)(11), and the presence and concentration of anions (Cl − , SO 4 2− , CO 3 2− , and PO 4 3− at concentrations of 5 and 20 mM).…”

“…[6] Several affecting factors have been reported for the photocatalytic removal of dyes in water using TiO 2 , including the material properties (e.g., pore structure and surface area, particle size, crystal phase, and band gap energy) and environmental conditions (e.g., catalyst dosage, solution pH, dye concentration, and oxidants). [6][7][8] However, the most disadvantages of pure TiO 2 include (i) high recombination of photo-excited electron-hole pairs (e.g., low quantum efficiency), (ii) working only under UVA irradiation, and (iii) difficulty in material recovery and reuse after water treatment. Therefore, several methods have been applied to improve the performance of TiO 2 for dye treatment in water, including doping with metals and nonmetals, surface modification with metals and metal oxides, and combination with other materials to form composite materials.…”

Effect of pH on the Performance of Bi2O2CO3 Nanoplates for Methylene Blue Removal in Water by Adsorption and Photocatalysis

“…Among them, photocatalysts are developed and increasingly used for practical applications in the treatment of air pollution and water pollution [4]. Some photocatalytic nanomaterials are capable of treating and degrading dyes, such as TiO2 and its modified forms [5][6][7][8], ZnO [9][10][11], and β-Bi2O3/Bi2O2CO3 [12]. Among them, the Bi2O2CO3 emerges as a new and effective material for adsorption and photocatalytic application.…”

“…Depending on the preparation method, nanomaterials have different physical, chemical, and photocatalytic properties [13]. Besides, the photocatalytic efficiency of the materials is affected by environmental conditions such as temperature, pH, concentration, exposure time, and light intensity [8]. In particular, the pH value greatly affects the treatment efficiency of a photocatalytic process because the ions to be treated will transform into different forms and the material properties are also affected when the pH changes [14].…”