Impact of the Ultraviolet Photolysis of Monochloramine on 1,4-Dioxane Removal: New Insights into Potable Water Reuse
| Autor: | Haizhou Liu, Stephen P. Mezyk, Kenneth P. Ishida, Kylie D. Couch, Wei Li, Samuel Patton |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Health
Toxicology and Mutagenesis Radical 02 engineering and technology 010501 environmental sciences medicine.disease_cause Photochemistry 01 natural sciences chemistry.chemical_compound medicine Environmental Chemistry Waste Management and Disposal Scavenging 0105 earth and related environmental sciences Water Science and Technology Chloramine Ecology Photodissociation 1 4-Dioxane 021001 nanoscience & nanotechnology Pollution chemistry Wastewater Environmental chemistry Degradation (geology) 0210 nano-technology Ultraviolet |
| Zdroj: | Environmental Science & Technology Letters. 4:26-30 |
| ISSN: | 2328-8930 |
| DOI: | 10.1021/acs.estlett.6b00444 |
| Popis: | Although chloramines are ubiquitously present during ultraviolet-driven advanced oxidation processes (UV/AOP) that are becoming increasingly important for potable water reuse, the photochemistry of chloramines in treated wastewater, and the associated effects on trace chemical contaminant degradation, are unknown. This study investigated the fundamental radical chemistry involved in monochloramine (NH2Cl) photolysis and its efficiency in degrading 1,4-dioxane using a low-pressure Hg lamp (λ = 254 nm). These results showed that the UV fluence-normalized rate of 1,4-dioxane degradation in UV/NH2Cl ranged between 1.1 × 10–4 and 2.9 × 10–4 cm2·mJ–1. The photolysis of NH2Cl produced NH2• and Cl•, which further transformed to a series of reactive radical species. An optimal NH2Cl dosage for 1,4-dioxane degradation was observed at a NH2Cl/1,4-dioxane concentration ratio of 8.0, while excess NH2Cl scavenged reactive radicals and decreased the treatment efficiency. Scavenging experiments and probe compound calcula... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|