Abstract
Ozonation of pentachlorophenol (PCP) with biological treatment were studied in distilled water (D.W.) and secondary effluents. Ozone was supplied into batch reactor at 6.25mgO3·l-1·min-1 or 0.625mgO3·l-1·min-1. PCP was easily decomposed by a few minutes-ozonation in D.W., but dissolved organic carbon (DOC) was not removed perfectly, even if 120 minutes-ozonation. PCP and the intermediates produced in an early stage of ozonation were not biodegraded. Improvement of biodegradability in PCP was required for at least 10 min of ozonation. One mg·l-1 of PCP was ozonated in buffer solution and secondary effluents, which contained 18-28 times higher DOC than PCP. Decomposition rate of PCP in secondary effluents by ozonation decreased one third compared with that in buffer solution, however, PCP was decomposed selectively from many other organic matters in secondary effluents by ozone.
