ORP and ozonization

V

Thread Starter

Vereecken Johan

Hello,

When treating a complex pharmaceutical wastewater with ozone (and with/without UV) the online measured ORP gets very negative (from +90mV to
-700mV !!). One would expect an oxidation. Measuring the ORP (of samples taken in time) of this treated wastewater after a day (when all radicals are gone) gives a rise in time. When treating the same water with peroxide (w & w/o UV) and oxygen together the online measured ORP rises as it should. The pH-measurement in all cases gives reproducable results.

Could it be that the ozone radicals interfere with the glass membrane and give a wrong result? Or are radicals much stronger reducing agents than
oxygen and UV are oxidizers (which seems pretty weird to me)?

We are using a Yokogawa redox combined glass electrode with gold surface ring in a flow through cell.

Any clues/experiences ?


Johan Vereecken
Vito - PRODEM
Boeretang 200 2400 Mol Belgium
voice: +32 14 33 69 35 fax: +32 14 32 65 86
mailto:[email protected] http://www.vito.be

For e-mail security and authenticity:
PGP DH/DSS Key ID: 0x8F44FDB4
 
Thread starter Similar threads Forum Replies Date
B Sensors & Calibration 0
J Sensors & Calibration 5
I Sensors & Calibration 2
C Sensors & Calibration 7
Top