Treatment with Ozone. In order to establish the efficiency
of ozonation without catalyst, the effect of two variables (pH and
time) on COD, color, and turbidity removal was investigated. The
results are shown through Figures 1-4.
Figure 1 shows the COD as function of treatment time at
different pH conditions. There can be distinguished three kinetic
stages through the profiles depicted in Figure 1. The first one is
associated to the first 5 min of treatment where a clearly more
rapid oxidation rate (given by COD diminishment rate) than the
one observed in the range of 5-15 and 15-60 min of treatment
occurs. Since the reacting solution is a mixture of effluents of
several industries (pharmaceutical, automotive, painting, textile,
food, and chemical), the presence of several compounds and