Honeywell manual January UDA2182 Universal Dual Analyzer Product Manual 211

Appendices

negative. The chromium, an oxidizing ion, Cr+6, accepts electrons and makes the electrode more positive. The net electrode potential is related to the ratio of concentrations of reducing and oxidizing ions in the solution.

Potential cannot be used as monitor of effluent

This electrode potential is extremely sensitive in measuring the degree of chrome treatment in the reaction tank. However, it cannot be related to a definite concentration of chrome and, therefore, cannot be used as a final effluent monitor of chrome concentration.

Importance of clean electrode

Reliable ORP measurements require a very clean metal electrode surface. Clean the electrodes routinely with a soft cloth; dilute acids, and/or cleaning agents to promote fast response. Control at low pH levels in the first stage of treatment has also been found to help maintain clean ORP electrodes.

January 2009 UDA2182 Universal Dual Analyzer Product Manual 211