ANALYTICAL CHEMISTRY, VOL. 51,
[O,IU 0.37 0.67 1.03 1.26
[ 0 3 1 b
0.32 0.74 0.15 1.65
river waterd
l03l" 0.29 0.32 0.49 0.55 0.96
secondary sewage effluente
[0,lb [O,l" 0.47
1979
2319
could be maintained and measured. This was necessary since ozone is highly unstable at high pltl values (20). Using an experimental arrangement similar to that of Figure 2 , a microprocessor-controlled electrode characterization system was programmed to automatically regulate the rate of ozone production based on electrode measurements. The control of ozonation processes based on the in situ measurement of residual ozone is one of the most promising applications of the electrode system and is currently being developed by our laboratory.
Table 111. Comparison of Ozone Measurements with the Voltammetric Membrane Ozone Electrode and DPP of P A 0 tap water'
NO. 14, DECEMBER
0.20 0.25 0.39 0.33 0.43 0.35 0.65 0.53 0.95 0.76 1.05 Concentration determined by DPP and PAO. Concentration determined by electrode. ' pH reduced t o 6.5. pH 8.5. e pH reduced to 7.3. 0.11
0.32 0.73 0.99 1.28
LITERATURE CITED Boeiter, E. D.: Putnam, G. L.; Lash, E. I . Anal. Cheni. 1950, 22, 1533. Flam, D. L.; Anderson, S. A. fnviron Sci. Techno/. 1975, 9 , 660. Standard Methods fw the Examination of Water and Wastewater", 13th ed.; American Public Health Association, 1971. Schecter, H. Water Res. 1973, 7, 729. Nosova. K. I.; Rakov, A. A.; Veseioovskii, V. I. Rus:;. J . Phys. Chem. ( f n g l . Trans/.)1959, 33, 349. Johnson, D. C.; Napp. D. T.; Brukenstein, S. Anal. Chem. 1988, 40, 48. Tomashov, N. D.: Valiulina, A. 2. Russ. J . Phys. Chem. (Engl. Trans/.) 1952, 26, 417. Nosova, K . I.: Rakov, A. A.; Veselovskii, V. I Russ. J . Phys. Chem. IEnol. Trans/.\ 1959. .., 37. . , 349 . . Ra
