Efficiency of the catalytic ozonation processes using nanoparticles deposited on pumice in the removal of bisphenol A

Abstract

ABSTRACT Endocrine-disrupting compounds (EDCs) areconsidered as an emerging group of trace contaminants detected in the environment worldwide. Bisphenol A (BPA) is one of these toxic pollutants that arereleased mainlyfrom industries and can cause serious health and environmental problems.Thus, in this study, titanium dioxide and zirconium dioxide particles were deposited on pumice, and then the efficiencies of O3/nTiO2/H2O2 and O3/nZrO2/H2O2on BPA removal were studied under different operational conditions. The results showed thatBPA removal efficiency was increased by increasing the pH, contact time, catalyst dosage and concentration of H2O2 and maximum removal efficiency for both studied processes was ≈100% at optimum conditions, i.e. pH of 11, are action time of 30 min, catalyst dosages of 4 g/L for O3/nTiO2/H2O2 and 12 g/L for O3/nZrO2/H2O2, H2O2 concentration of 2 mmol/L for O3/nZrO2/H2O2and 5 mmol/L for O3/nTiO2/H2O2, and initial BPA concentrations of 20 mg/L.Increasing the catalyst dose to a certain level, increases the production of hydroxyl radicals, which, in turn, increases the degradation of BPA. The pumice XRD pattern coated with TiO2 and ZrO2 nanoparticles shows the main and derivative elements of pumice, including pyroxene, magnetite feldspar mica, and SiO2.FTIR spectra for TiO2 and ZrO2 nanoparticles showed that the peaks at 455 and 457 cm−1 are related to the C-N-C bands in amine functional groups. We found that the studied integrated catalytic ozonation processes (COP)have high efficiency in removing BPA, therefore it can be used as asuitable and effective methods for removal of such organic pollutants from aqueous solution.