ELECTROCHEMICAL ANALYSIS OF 304 STAINLESS STEEL CORROSION IN CHLORINE DIOXIDE

摘要

Pulp bleached with chlorine dioxide has better brightness and higher strength properties, and there is less bleaching effluent released to the environment. More and more domestic pulp mills have used chlorine dioxide bleaching instead of traditional bleaching. At present, the corrosion for equipment is the main factor that influences its popularity. In this paper, the corrosion of 304 stainless steal in chlorine dioxide in different temperature, concentration, and pH value are studied by Tafel curves and electrochemical measurement. Research has shown that chlorine dioxide causes strong corrosion to 304 stainless steel. The increase of concentration and temperature of chlorine dioxide accelerates the cathodic and anodic process, increases the electric current of corrosion, and accelerates the corrosion rate of stainless steel. Chlorine dioxide in acid condition damages the passive film and causes the strongest degree of corrosion to the stainless steel; when the concentration is 8g/L, the temperature is 60 , and the pH value is 2, °C the corrosion current density reaches 5.587×10-4 A/cm2. The writer makes a totally general analysis of the corrosion of stainless steal in chlorine dioxide, providing theoretical references for weakening the extent of corrosion of stainless steal.