Biodegradation of tetramethylammonium chloride wastewater and inorganic nitrogen removal by a mixed culture. Issue 1 (February 2022)

• Record Type: Journal Article
• Authors: Liu, Yu-Cheng; Hu, Yu-Chen; Chu, I.-Ming; Wei, Yu-Hong; Tsai, Shen-Long
• Is Part Of: Journal of environmental chemical engineering. Volume 10:Issue 1(2022)
• Publication Date: 2022-02
• Subjects: Tetramethylammonium chloride -- Wastewater treatment -- Denitrification -- Biodegradation -- Kinetics; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2021.106931
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: The disposal of wastewater containing tetramethylammonium chloride (TMAC) generated from the semiconductor and photoelectric industries is a challenging problem due to the limited information is available regarding its treatability. This study aims to investigate the feasibility of using biological processes to treat TMAC. An activated sludge collected from a lake near the Southern Taiwan Science Park was used. Various operational parameters, including operating temperature, pH conditions and TMAC dosages were evaluated for the optimal condition. Results showed that the activated sludge could successfully degrade TMAC, and subsequently achieve simultaneous nitrification and denitrification (SND) of the nitrogen-containing intermediates under mild conditions (pH at a range of 3–7 and temperature at a range of 20–40 °C). Besides, more than 60% of the nitrogen-containing intermediates were converted into gaseous nitrogen (N2 ). TMAC biodegradation was found to follow first-order kinetics. The observed rate constant of TMAC biodegradation increased from 0.64 ╳ 10 −4 to 9.57 ╳ 10 −4 1/min as the concentration of TMAC decreased. In addition, TMAC demethylation was identified as the rate-limiting step of the entire reaction. Major functional organisms of the activated sludge were identified as Mycobacterium, Ochrobactrum and Arthrobacter species which are aerobic and acidophilic strains. This study can be an important reference for future researches attempting to treatment TMAC wastewater by biological processes. Graphical Abstract: ga1 Highlights: An adapted consortium was used to remove tetramethylammonium chloride (TMAC). Simultaneous nitrification and denitrification were achieved under mild conditions. TMAC biodegradation followed first-order kinetics and its mechanism was inferred. Major functional genera were Mycobacterium, Ochrobactrum and Arthrobacter .