Practical Aspects of Ozone Measurement

In order to evaluate the results of the experimental work, an ozone balance over the reactor is essential. Measurement of the ozone gas concentration in the in- and outlet of the reactor system as well as the liquid ozone concentration are necessary to complete the balance. This is true for both steady state and non-steady state systems. The monitoring of nonsteady state systems, in which the concentrations change over time, requires more measurements. 

Continuous analytical methods (amperometric and UV-absorption methods) are advantageous. However, sometimes only discontinuous methods (titrimetric and some photometric methods) are available due to expense. In such cases it is important to measure immediately after sampling to avoid the decay of ozone and in the case of liquid ozone to avoid degassing. Discontinuous photometric methods requiring the addition of chemicals to the sample can be converted to a continuous method by combination with flow injection analysis (FIA). This analytical technique requires instrumentation and is not easy to handle. 

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