Nitrogen transformation of 41 organic compounds during SCWO: A study on TN degradation rate, N-containing species distribution and molecular characteristics
Yang, B; Cheng, Z; Tang, Q; Shen, Z
| HERO ID | 4739603 |
|---|---|
| In Press | No |
| Year | 2018 |
| Title | Nitrogen transformation of 41 organic compounds during SCWO: A study on TN degradation rate, N-containing species distribution and molecular characteristics |
| Authors | Yang, B; Cheng, Z; Tang, Q; Shen, Z |
| Journal | Water Research |
| Volume | 140 |
| Page Numbers | 167-180 |
| Abstract | Supercritical water oxidation (SCWO) of 41 N-containing compounds was examined under a stable temperature and pressure of 450 °C and 24 MPa, respectively, reaction time ranged from 0.5 to 6 min with 500% excess oxygen, resulted in the degradation rate constants of total organic carbon (kTOC) and total nitrogen (kTN) were 0.162-3.693 and 0.065-0.416 min-1, respectively. The N-containing products were primary N2, ammonium and nitrate. As for amino-group compounds, the main product was ammonia, while for nitro-group compounds, nitrate was the predominant. In terms of diazo and N-heterocyclic group compounds, the main products generally were nitrate and ammonium, respectively. Interestingly, 2-, 3- and 4-nitroaniline, containing both of nitro and amino group, would directly decompose into N2. The reaction pathways of acid orange 74 was proposed based on Fukui indices, which generally included denitrification, ring-open and mineralization. Density functional theory (DFT) method was applied to calculate the quantum properties of the 41 N-containing compounds in order to further examine the relationship between TN removal and molecular structural characteristics. The correlation result showed that among all the 17 molecular characteristics, F(+)n, F(-)n, F(0)n, and EHOMO achieved high correlation coefficients. |
| Doi | 10.1016/j.watres.2017.12.080 |
| Pmid | 29709766 |
| Wosid | WOS:000447359000016 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |