The degradation of diclofenac (DCF), a commonly used nonsteroidal anti-inflammatory drug, by Fe 2+ /chlorine and Fe 2+ /PMS processes was comparatively investigated. The influencing factors of pH, Fe 2+ and oxidant dosage on DCF degradation efficiency were evaluated and optimized. Typically, with an initial solution pH of 5, an Fe 2+ dosage of 70 μM, and a chlorine or PMS dosage of 70 μM, the degradation efficiency of DCF using the Fe 2+ /chlorine and Fe 2+ /PMS processes reached 94.2% and 79.7%, respectively, within 10 min. Quenching tests indicated the coexistence of •OH and RCS in the Fe 2+ /chlorine system, and both SO 4 ●– and •OH were identified in the Fe 2+ /PMS system. In addition, Fe(IV) was also identified to participate in DCF degradation in two systems based on the oxidation of PMSO to PMSO 2 . The degradation products and pathways of DCF were elucidated by LC/TOF/MS analysis and DFT calculations. It was assumed that the degradation pathway of DCF involves hydroxylation, dechlorination, decarboxylation, cleavage of the C-N bond, and chlorine substitution. In addition, trichloromethane (TCM), dichloroacetaldehyde (DCAL), dichloroacetonitrile (DCAN) and trichloronitromethane (TCNM) were also detected in the Fe 2+ /chlorine process, and these chlorinated DBPs initially increased and then decreased with prolonged reaction time, indicating that Fe 2+ /chlorine is capable of controlling DBPs formation. Finally, the acute and chronic toxicity of DCF and its degradation products were evaluated by the ECOSAR program.
The extraction of Fe(III), Ni(II) and Co(II) from a Ni(II)-Co(II) solution containing Fe(III) was analyzed in a chloride medium using a mixed extractant consisting of 50% ( v /v) tributyl phosphate (TBP), 20% (v/v) 2-octanol and 30% (v/v) kerosene. The extraction of 0.5 mol/L Fe(III) in 4 mol/L hydrochloric acid reached 97%, and the consumption of chloride ions was investigated. Nickel(II) ions were not detectably extracted by TBP, with an inclusion of <1.1%. Compared with Fe(III), TBP extracted only a small amount of Co(II). The iron complexes formed by TBP and 2-octanol were [H 2 FeCl 4 · 2TBP] and [H 2 FeCl 4 · 5(2-octanol)], and the possible compositions of Co-containing extracts were [H 2 CoCl 4 · 2TBP] and [H 2 CoCl 4 ] · n[2-octanol]. An industrial process consisting of two-step extraction was designed to achieve the separation of Co(II) and Fe(III), resulting in a decrease in the Fe/Co mass ratio from 0.46 to <3.5 × 10 −4 in the raffinate.
危险品化学品经营许可证（带存储）