Term: Corrosion inhibitor
– Types of Corrosion Inhibitors:
– Benzotriazole forms an inert layer on copper to inhibit corrosion.
– Inhibitors depend on the material being protected and the corrosive agents.
– Oxygen, hydrogen sulfide, and carbon dioxide are common corrosive agents.
– Reductive inhibitors like amines convert oxygen to water to prevent corrosion.
– Corrosion inhibitors can form passivating coatings on metal surfaces.
– Applications of Corrosion Inhibitors:
– Added to coolants, fuels, hydraulic fluids, engine oil, and boilers.
– Used on copper surfaces, in paints, oil field industry, and oil refineries.
– Volatile amines minimize acid effects in boiler water.
– Zinc phosphate is an anticorrosive pigment in paint.
– Antiseptics like benzalkonium chloride counter microbial corrosion.
– Corrosion Control in Tap Water:
– Factors affecting tap water pipe corrosion include pH and hardness.
– Methods include adjusting pH, adding phosphates, or silicates as inhibitors.
– Orthophosphates prevent leaching of lead and copper in tap water.
– Polyphosphates control iron and manganese in tap water.
– Corrosion control is crucial in areas with lead and copper piping systems.
– Fuel Additives for Corrosion Resistance:
– DCI-4A is used in jet fuels and acts as a lubricity additive.
– Various resources provide information on protective coatings and corrosion resistance.
– Nitriding enhances corrosion and wear fatigue resistance.
– Corrosion inhibitors protect fuel distribution systems.
– Inhibitors prevent corrosion in hydrocarbon fuels.
– References on Corrosion Inhibitors:
– Ullmann’s Encyclopedia of Industrial Chemistry discusses corrosion.
– EPA provides technical recommendations on optimal corrosion control.
– Studies evaluate types, mechanisms, and electrochemical evaluation of inhibitors.
– Research reviews corrosion inhibition by benzotriazole.
– Investigations analyze the impact of corrosion control interruptions on water systems.
A corrosion inhibitor or anti-corrosive is a chemical compound added to a liquid or gas to decrease the corrosion rate of a metal that comes into contact with the fluid. The effectiveness of a corrosion inhibitor depends on fluid composition and dynamics. Corrosion inhibitors are common in industry, and also found in over-the-counter products, typically in spray form in combination with a lubricant and sometimes a penetrating oil. They may be added to water to prevent leaching of lead or copper from pipes.
A common mechanism for inhibiting corrosion involves formation of a coating, often a passivation layer, which prevents access of the corrosive substance to the metal. Permanent treatments such as chrome plating are not generally considered inhibitors, however: corrosion inhibitors are additives to the fluids that surround the metal or related object.