Study of Fe3O4/PS System in Degrading BPA in Aqueous Solution

The degradation of bisphenol A (BPA) by Fe3O4/persulfate system was investigated in aqueous solution. The influences of the initial concentrations of Fe3O4, persulfate (PS) and BPA, pH value, and initial reaction temperature on BPA removal were studied. The radical species was investigated by adding excessive dose of scavenger (methanol (MeOH) and tert-butanol (TBA)) into Fe3O4/PS system for the purpose of radical scavenging. The degradation products of BPA were detected by gas chromatography-mass spectrometry (GC-MS). The recyclability of Fe3O4 was also evaluated. The BPA removal rate of 80.7% was achieved under the following conditions: [BPA]0 = 1 mg L-1, [PS]0 = 0.2 mM, [Fe3O4]0 = 0.1 g L-1, T0 = 20 ± 1 ºC, pH0 = 6.8 ± 0.2. The results confirmed that the main free radicals in the reaction process were sulfate radicals, followed by hydroxyl radicals. Some intermediate products of BPA degradation, such as phenols, benzoquinones and benzoic acid were identified by GC-MS.