Abstract
Electrochemical current noise (ECN) measurements were carried out in mixtures of 3% NaCl electrolyte in diesel under stirred conditions (0 to 2000 rpm) using a Rotating Electrodes System (RES) which includes three mild steel concentric electrodes embedded in activated polyester resin. Chemical activation of the resin allowed electrochemical measurements in the water in oil emulsion system. A 0.2 to 15 % in volume range of 3% NaCl electrolyte addition was studied. Three distinctive noise patterns were obtained from electrochemical current noise (ECN) time-series: a) a low noise baseline for diesel in absence of electrolyte, diesel with small additions of electrolyte and/or low flow rates, b) a low noise signai with current bursts superimposed obtained from relatively small additions of electrolyte and high rotation rates and c) a high amplitude signal for high rotation rates and relatively high additions of electrolyte. For case b, the number and intensity of current bursts is indicative of proximity to cases a or c. These results contrast with experiments carried out with a conventional non-activated resin which is insensitive to the range of electrolyte additions or to stirring conditions. This method can be implemented for water in oil systems where early corrosion detection is desirable.
