A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Reductive Degradation of N-Nitrosodimethylamine via UV/Sulfite Advanced Reduction Process: Efficiency, Influencing Factors and Mechanism
N-nitrosodimethylamine (NDMA), as an emerging nitrogenous disinfection byproduct, is strictly controlled by multiple countries due to its high toxicity in drinking water. Advanced reduction processes (ARPs) are a new type of water treatment technology that can generate highly reactive reducing radicals and make environmental contaminants degrade rapidly and innocuously. In this study, a systematic investigation on the kinetics of the NDMA degradation via the chosen UV/sulfite ARP and the impacts of some key parameters of reaction system was conducted. The results indicated that the UV/sulfite ARP was an efficient and energy saving method for the reductive degradation of NDMA. A total of 94.40% of NDMA was removed using the UV/sulfite ARP, while only 45.48% of NDMA was removed via direct UV photolysis under the same reaction conditions. The degradation of NDMA via the UV/sulfite ARP followed pseudo-first-order kinetics. Increasing both the UV light intensity and sulfite dosage led to a proportional increase in the NDMA removal efficiency. The alkaline condition favored the degradation of NDMA, with the removal efficiency increasing from 21.57% to 66.79% within the initial 5 min of the reaction when the pH increased from 3 to 11. The presence of dissolved oxygen substantially decreased the removal efficiency of NDMA due to the formation of oxidizing superoxide radicals, which competed with NDMA by capturing the reducing active radicals during the reaction. An analysis of the degradation products indicated that several refractory intermediates such as dimethylamine, methylamine and nitrite were completely decomposed via the UV/sulfite ARP, and the final degradation products were formate, ammonia and nitrogen.
Reductive Degradation of N-Nitrosodimethylamine via UV/Sulfite Advanced Reduction Process: Efficiency, Influencing Factors and Mechanism
N-nitrosodimethylamine (NDMA), as an emerging nitrogenous disinfection byproduct, is strictly controlled by multiple countries due to its high toxicity in drinking water. Advanced reduction processes (ARPs) are a new type of water treatment technology that can generate highly reactive reducing radicals and make environmental contaminants degrade rapidly and innocuously. In this study, a systematic investigation on the kinetics of the NDMA degradation via the chosen UV/sulfite ARP and the impacts of some key parameters of reaction system was conducted. The results indicated that the UV/sulfite ARP was an efficient and energy saving method for the reductive degradation of NDMA. A total of 94.40% of NDMA was removed using the UV/sulfite ARP, while only 45.48% of NDMA was removed via direct UV photolysis under the same reaction conditions. The degradation of NDMA via the UV/sulfite ARP followed pseudo-first-order kinetics. Increasing both the UV light intensity and sulfite dosage led to a proportional increase in the NDMA removal efficiency. The alkaline condition favored the degradation of NDMA, with the removal efficiency increasing from 21.57% to 66.79% within the initial 5 min of the reaction when the pH increased from 3 to 11. The presence of dissolved oxygen substantially decreased the removal efficiency of NDMA due to the formation of oxidizing superoxide radicals, which competed with NDMA by capturing the reducing active radicals during the reaction. An analysis of the degradation products indicated that several refractory intermediates such as dimethylamine, methylamine and nitrite were completely decomposed via the UV/sulfite ARP, and the final degradation products were formate, ammonia and nitrogen.
Reductive Degradation of N-Nitrosodimethylamine via UV/Sulfite Advanced Reduction Process: Efficiency, Influencing Factors and Mechanism
Xiaosong Zha (author) / Shuren Wang (author) / Deyu Zhang (author)
2023
Article (Journal)
Electronic Resource
Unknown
Metadata by DOAJ is licensed under CC BY-SA 1.0
Correlation analysis of pollutant factors influencing the sulfite/UV-L advanced reduction process
| Online Contents | 2018
Correlation analysis of pollutant factors influencing the sulfite/UV-L advanced reduction process
| Springer Verlag | 2017
Factors influencing the photodegradation of N-nitrosodimethylamine in drinking water
| Springer Verlag | 2009
Degradation of N-nitrosodimethylamine (NDMA) in water by UV-O3
| Online Contents | 2009
Effect of ozonation on minocycline degradation and N-Nitrosodimethylamine formation
| Taylor & Francis Verlag | 2018