Effect of sodium nitrite–borax blend on the corrosion rate of low carbon steel in industrial water medium

Effects of sodium nitrite–borax blend on low carbon steel corrosion in industrial water medium at various temperatures, various inhibitors concentration of sodium nitrite and borax and at various rotational speeds of the specimens have been studied by gravimetric and polarization measurements. Optimization of the three variables was made and correlating the results obtained by using Box–Wilson statistical method. The process was considered as adsorption of inhibitor ions in oxide layer which form a passive film on the metal surface. The Langmuir isotherm was found to be the best description for the adsorption process. Thermodynamic parameters were evaluated and discussed.