| Autor: |
Xiang-zhong Li, Ling Ding, Hai-chao Liang |
| Rok vydání: |
2012 |
| Předmět: |
|
| Zdroj: |
Separation and Purification Technology. 91:117-124 |
| ISSN: |
1383-5866 |
| DOI: |
10.1016/j.seppur.2012.01.006 |
| Popis: |
This study demonstrated a new approach of odorous gas treatment in a wet scrubbing-oxidation system with in situ generation of ferrate(VI), in which gaseous CH 3 SH can be quickly absorbed by aqueous alkaline solution and rapidly oxidized by liquid ferrate(VI) generated through electrochemical synthesis in situ. In this study, the electrochemical generation of ferrate(VI) in aqueous NaOH solution was studied and the experiments demonstrated that a maximum current efficiency to generate ferrate(VI) occurred at 14 M NaOH concentration, while an applied current density of 14.06 mA cm −2 was applied. Then the self-decomposition of ferrate(VI) in such strong alkaline solutions was studied, and the results showed that ferrate(VI) behaved more stable in the stronger alkaline solution. Furthermore, the reactivity of ferrate(VI) with CH 3 SH in this highly-concentrated NaOH solution was investigated under different reaction conditions as the first time. The experimental results confirmed that CH 3 SH can be fully oxidized by ferrate(VI) to sulphate ion as a final product. The second-order reaction model is suitable to describe the kinetics of CH 3 SH reaction with ferrate(VI) in the strong alkaline solution. Meanwhile, stoichiometry of ferrate(VI) reaction with CH 3 SH in aqueous solution was determined with a minimum molar ratio of 2.20:1 (Fe(VI):CH 3 SH) to destruct CH 3 SH effectively and a higher molar ratio of 4.53:1 to convert CH 3 SH to sulphate ion completely. The experiments also demonstrated that the NaOH concentration in aqueous solution would be a key parameter and the best performance of CH 3 SH removal was achieved at the optimum NaOH concentration of 6 M under our experimental conditions due to an optimum balance between the oxidation potential of ferrate(VI) and its generation rate in this wet scrubbing-oxidation system. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect