Determination of phenol degradation in chloride ion rich water by ferrate using a chromatographic method in combination with on-line mass spectrometry analysis

The degradation of phenol in Cl--rich water by Fe(vi) was investigated using both chromatographic methods (HPLC and IC) and an on-line direct mass spectrometry (MS) analysis technique. Participation of Cl- during phenol degradation was observed through the formation of p-chlorophenol and coupled species with phenol. Though only a small concentration of Cl- was involved in the reaction, the presence of Cl- could affect the behavior of phenol substantially. With the increase of the Cl- concentration, generation of p-benzoquinone and p-chlorophenol was increased. Meanwhile, phenol in the bulk solution displayed a sharp decline followed by a gradual increase. The developed on-line MS analysis facilitated real-time monitoring of phenol changes in the reaction system. The results showed that phenol degradation by Fe(vi) with the presence of a high concentration of Cl- followed a second-order reaction process. The degradation pathway of phenol was also identified, with p-chlorophenol, p-benzoquinone, maleic acid and formic acid as the main byproducts.