Application of a novel definitive screening design to in situ chemical oxidation of acid orange-II dye by a Co2+/PMS system
| Autor: | Jiahui Xian, Chunyong Zhang, Degang Fu, Wei Chen |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
chemistry.chemical_classification
General Chemical Engineering Batch reactor chemistry.chemical_element 02 engineering and technology General Chemistry Orange (colour) Electrolyte 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Hydroxylation chemistry.chemical_compound chemistry In situ chemical oxidation Screening design Chlorine Humic acid 0210 nano-technology Nuclear chemistry |
| Zdroj: | RSC Advances. 8:3934-3940 |
| ISSN: | 2046-2069 |
| DOI: | 10.1039/c7ra13446k |
| Popis: | In this work, a novel definitive screening design (DSD) was initially used to investigate the in situ chemical oxidation of acid orange-II (AO II) dye using a homogeneous cobalt-catalyzed peroxymonosulfate (Co2+/PMS) system. Experiments were performed in a batch reactor using a synthetic AO II solution containing cobalt ions, humic acid (HA) and five electrolyte salts (NaCl, NaNO3, NaHCO3, Na2SO4 and NaH2PO4). The effects of nine operating variables on AO II degradation: NaCl concentration (0–20 mM), NaH2PO4 concentration (0–20 mM), NaHCO3 concentration (0–20 mM), NaNO3 concentration (0–20 mM), Na2SO4 concentration (0–20 mM), HA concentration (0–40 mg L−1), PMS concentration (2–10 mM), AO II concentration (0–100 mg dm−3) and Co2+ concentration (0–1.36 mM), were investigated. Analysis of a DSD model revealed that only four variables were statistically significant. Besides, our results indicated that there were no significant interactive effects between the five anions employed. Thereafter, a central composite rotatable design (CCRD) was adopted to further optimize these significant variables. A CCRD model describing AO II conversion as a function of PMS concentration, NaCl concentration and Co2+ concentration was then constructed and used to explore the final optimal operating conditions. As a consequence, the combination of DSD and CCRD allowed reducing the number of experiments from over 600 to only 39. Lastly, a plausible reaction sequence concerning the oxidation of AO II in the Co2+/PMS/Cl− system was also proposed. The route of AO II oxidation involved hydroxylation and chlorination, signifying the roles of both sulfate radicals and active chlorine species. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|