Ozone Results
Creighton University
Part 4. Optimizing Conditions

Optimal Voltage Determination.  (Tere page 17)  We have determined that the optimal voltage for both the Pt and Pb variants is the 6 V setting on the DC power supply.  Higher voltages give similar results to the 6 V setting.  Lower voltages give poorer results.

Also, the actual voltage for each setting is:
Setting    Actual (Pt/C)    Actual (Pb/C)
1.5 V        1.59
3 V           3.06
4.5 V        4.67
6 V           6.23
7.5 V        7.73
9 V           9.27
12 V        12.45

Tere determined the "useful lifetime of the ozone generators by letting them run and monitoring ozone production every hour.  She found that for Pt/C, the generator lasts about 8 hours (page 16) and the Pb/C generator about 4 hrs (page 18)

Tere also investigated the importance of the sulfuric acid concentration.  She used 3 M, 4 M, 5 M and 6 M.  We measured gas production (in mL) and ozone production (by reaction with excess KI and titration with thiosulfate).  The ratio of volume of thiosulfate to volume of gas production is proportional to the percent ozone in the produced gas.  Results do not indicate an ideal concentration.  The ratio remained quite similar regardless of the concentration.