Temperature effect on the complex conductivity of Adblue

Diesel engines have a strong contribution to the NOx in air; this amount of NOx should be reduced because it´s toxic and harmful to the environment. To enable this reduction, manufacturers of commercial vehicles developed the selective catalytic reduction (SCR) technology. This technology uses Adblue in order to reduce the NOx-content in the exhaust gas stream. Adblue is an Aqueous Urea Solution made with 32.5% urea and 67.5% de-ionized water. The quality of Adblue has a big influence on the efficiency of the SCR. A quality sensor was developed in order to determine the contamination or adulteration of Adblue solution by water or other additive using Impedance Spectroscopy. The temperature has an influence on the electrochemical behavior of the Adblue solution; in this work we study the effect of temperature on the measurement results. It was shown that at a constant concentration the impedance of the Adblue change with the temperature which is an important factor to be considered in the treatment of the measurement results.