Removal of the 2-Mercaptobenotiazole from Model Wastewater by Ozonation

Abstract

The feasibility of ozonation process for 2-mercaptobenzothiazole (2-MBT) removal follows from results of ozonation of the model wastewater. Total removal of 2-MBT was observed after 20 minutes of ozonation. Very good reproducibility of repeated ozonation trials including sampling and analysis was observed. However, the majority of dissolved organic carbon (DOC) and chemical oxygen demand (COD) remained in the reaction mixture. Benzothiazole (BT) and 2-hydroxybenzothiazole (OBT) intermediates were identified during degradation of 2-MBT with ozone. In addition to the above benzothiazole derivatives, the creation of some other organic compounds follows from results of mass balance. The best fits of experimental data were obtained using the first kinetic model for 2-MBT and zero-order kinetic model for COD and DOC. The reaction time of 60 minutes can be considered as effective with regard to controlled oxidation in order to increase a portion of partially oxidized substances. Higher biodegradability and lower toxicity of ozonation products on respiration activity of activated sludge microorganisms was observed at higher ozonation time.

A Review of Environmental Occurrence, Fate, Exposure, and Toxicity of Benzothiazoles

“…Derco and colleagues reported degradation of 2-SH-BTH in a model wastewater batch reactor by ozonation and also observed formation of BTH and 2-OH-BTH as the reaction intermediates of 2-SH-BTH . Fiehn et al also observed a complete removal of 2-SH-BTH after 20 min of ozonation, while BTH and 2-OH-BTH levels increased with time and then reduced to zero after 60 min.…”

“…Summary of reported chemical degradation (A), biodegradation (B) and transformation pathways of benzothiazole and its derivatives (refs , Reddy and Quinn (1997); , De Wever et al (2001); , Reemtsma et al (1995); , Derco et al (2014); , Fiehn et al (1998); , Nika et al (2017); , Drotar et al (1987); , Besse et al (2001); , Haroune et al (2002); , Haroune et al (2004); , El-Bassi et al (2010); , De Wever et al (1998); , Brownlee et al (1992); , Kumata et al (1996); and , De Wever (1995)). Solid line refers to the suggested pathway based on empirical observations while the dotted line refers to the predicted pathway.…”

“…Derco and colleagues reported degradation of 2-SH-BTH in a model wastewater batch reactor by ozonation and also observed formation of BTH and 2-OH-BTH as the reaction intermediates of 2-SH-BTH. 90 and 2-SO 3 H-BTH after 6, 12.5, and 15 min, respectively, and BTs were completely removed after 55 min. 91 However, other research has shown that the presence of free radical scavengers such as carbonates during oxidation of BTH can reduce the degradation rate.…”

Removal of Aniline and Benzothiazole Wastewaters Using an Efficient MnO2/GAC Catalyst in a Photocatalytic Fluidised Bed Reactor

“…In addition, during the photocatalytic removal of ANI and BTH, the colour of the oxidised water also changed. Accordingly, these colour changes were observed by Jing et al [19] during the oxidation of effluents containing ANI and by De Wever et al [96] and Derco et al [97] in effluents with BTH, with colours including pink, reddish orange, reddish brown, and light yellow. Coloured intermediates were also observed in this work during the removal of ANI and BTH, whose main intermediates could correspond to p-benzoquinone, phenol, nitrobenzene, 2-mercaptobenzothiazole and aminophenol.…”

Degradation of 2-mercaptobenzothizaole in microbial electrolysis cells: Intermediates, toxicity, and microbial communities

“…It is a toxic, widespread, and poorly biodegradable pollutant of the aquatic environment, and many studies have confirmed that it is a strong allergen and potential mutagen for humans (Morsi et al, 2020a) (Allaoui et al, 2010). However, conventional biological wastewater treatment methods cannot effectively remove MBT from waste streams (Derco et al, 2014) because of the difficulty to biodegrade it (De Wever and Verachtert, 1994). As a consequence, the development of alternative technologies, such as photocatalytic degradation (Li et al, 2005) or the Fenton reaction (Wang et al, 2016), to mitigate its presence in contaminated streams has aroused extensive interest.…”