Performance of nZVI/H2O2 process in degrading polyvinyl alcohol in aqueous solutions

A rotating packed bed with blade packings was used to obtain nanoscale zero-valent iron (nZVI). Polyvinyl alcohol (PVA) was degraded by the nZVI/H2O2 process, and the effects of the addition of oxygen, pH, nZVI dosage, and H2O2 concentration on this process were determined. The efficiency of degradation of PVA in the presence of air exceeded that in the presence of nitrogen. The efficiency of degradation of PVA under acidic conditions was higher than that under alkaline conditions. The degradation of PVA by the nZVI/H2O2 process was optimized at a particular nZVI dosage and H2O2 concentration. At pH 3 with an nZVI dosage of 0.005 g/L and an H2O2 concentration of 1 × 10−4 mol/L in the presence of air, the nZVI/H2O2 process using the produced nZVI degraded 94% of the PVA in 1 min; this efficiency of degradation was much higher than that (1%) obtained using nZVI that was supplied by Alfa-Aesar.