Preparation of SiO2/TiO2 ceramic nano composite coating by sol-gel method on carbon steel and study the properties of it against corrosive ion in treated wastewater

Nowadays due to water shortage, the use of treated wastewater as sustainable solution has been considered by industrial units; especially in industrial cooling units and boilers. However the use of treated wastewater also has its own problems such as corrosion of metal parts that they are often made of carbon steel. Therefore different methods such as coating have been considered by the industrial user of treated wastewater in order to reduce corrosion. So in this study, SiO2/TiO2 Ceramic Nano composite coatings was put on Carbon Steel plates by Sol-Gel method and by dipping process for 100 seconds and microstructure and properties of produced ceramic coatings were investigated. The results showed that ceramic Nano composite coatings improved corrosion properties of Carbon Steel. In order to improve the properties and performance of the coating, the molar ratio of components and factors affecting performance of coating were evaluated till optimum coating with Nano structure and highest level of corrosion protection is provided. To evaluate the performance of coatings for corrosion protection, polarization curves and to determine the surface morphology, scanning electron microscope was used. In order to study the bonds type and functional groups in the optimal sol, infrared spectrum was used. The optimum corrosion protection coatings were studied in 3.5% sodium chloride solution. The results showed that the ceramic optimal deposited coating provides effective protection for the surface of Carbon Steel against corrosion in 3.5% sodium chloride solution.