Degradation of 2-MIB in aqueous solution by ZnOOH catalyzed ozonation

In this study, ZnOOH was used as a catalyst and its efficiency in removing trace organic matter, 2-methylisoborneol (2-MIB), in conjunction with ozone was investigated. The catalyst was characterized by X-ray diffraction (XRD), the Brunauer-Emmet-Teller (BET) method and Fourier transform infrared spectrometry (FT-IR). The performance of the ozone oxidation process alone and the O₃/ZnOOH system were both studied. Factors such as ozone dose, catalyst dosage, radical inhibitor and water qualities were analyzed to investigate their effects on catalysis activity and 2-MIB removal efficiency. Results showed that the removal of 2-MIB was better in O₃/ZnOOH system. The removal efficiency increased with the increase of catalyst dosage. However, the increase became inconspicuous when the dose was higher than 400 mg. Tert-butanol inhibits the removal of 2-MIB, and this effect was even more obvious in O₃/ZnOOH system. This indicates that O₃/ZnOOH system promotes the hydroxyl radical production, and removal reaction process in this system follows the mechanism of hydroxyl radical reaction. The water qualities also affected the removal of 2-MIB. Tap water was better than distilled water in the degradation of 2-MIB, while the effect of Songhua River was the weakest.