Chemistry Reference
In-Depth Information
from that moment, the rate of formation of hydrogen peroxide (by enzy-
matic reduction of oxygen taken up from the air) is equal to the rate of con-
sumption (in the disinfection reaction).
In order to ascertain the amount of hydrogen peroxide that was con-
sumed in the disinfection reaction, the experiment was repeated with prior-
disinfected cotton fabric. In this case, the hydrogen peroxide consumption
should be very low because the disinfection reaction has already been com-
pleted. This is shown in Fig. 3.10, curve 2. In this case, a linearly increasing
curve is obtained, indeed because the hydrogen peroxide concentration
increases owing to enzymatic transformation of oxygen. From the slope,
it can be seen that the hydrogen peroxide concentration increases with a
value of 7.1 ¥ 10
-4
gl
-1
s
-1
.The experiment shows very clearly that hydrogen
peroxide can be determined continuously, and that it is possible to obtain
industrially interesting concentrations by using enzymes for
in situ
produc-
tion of hydrogen peroxide. The key parameters in these processes are pH
and temperature to control the activity of the enzymes. The temperature
must not be too low, as otherwise insufficient hydrogen peroxide is pro-
duced, but also it must not be too high, in order to avoid de-naturation of
the enzyme catalyst.
3.5
References
1. Sawyer D.T., Sobkowiak A., Roberts J.L.,
Electrochemistry for Chemists
,Wiley,
New York, 1995.
2. Frant M.S., Ross J.W.,
Science
,
154
(1966) 1553.
3. Lundgrun D., Woermann D.,
Z. Phys. Chem.
,
207
(1998) 245.
4. De Strycker J., Westbroek P., Temmerman E.,
J. Electroanal. Chem.
,
565
(2004)
149.
5. De Strycker J., Westbroek P., Temmerman E.,
Glass Sci. Technol.
,
75
(2002) 175.
6. De Strycker J., Westbroek P., Temmerman E.,
Elec. Commun.
,
4
(2002) 41.
7. De Strycker J., Westbroek P., Temmerman E.,
J. Non-Cryst. Solids
,
289
(2001)
106.
8. De Strycker J., Gerlach S., Von Der Gonna G., Russel C.,
J. Non-Cryst. Solids
,
272
(2000) 131.
9. Smith P.J.S., Hammar K., Porterfield D.M., Sanger R.H., Trimarchi J.R.,
Microsc.
Res. Techn.
,
46
(1999) 398.
10. Qin Y., Bakker E.,
Talanta
,
58
(2002) 909.
11. Simonian A.L., Grimsley J.K., Flounders A.W., Schoeniger J.S., Cheng T., De
Frank J.J., Wild J.R.,
Anal. Chim. Acta
,
442
(2001) 15.
12. Schollmeyer E, Knittel D., Hemmer E.A.,
Betriebsmesstechnik in der Textil-
erzeugung und-veredlung
, Springer-Verlag, Heidelberg, 1988.
13. Morf W.E.,
Electroanal
,
7
(1995) 852.
14. Evans A.,
Potentiometry and Ion-Selective Electrodes
,Wiley, Chichester, 1987.
15. Covington A.K.,
Ion-Selective Electrode Methodology 1
, CRC Press, Boca
Raton, 1979.
