MITIGATION OF AMMONIUM CHLORIDE CORROSION ON CARBON STEEL IN REFINING UNIT

Ammonium chloride corrosion produces localized destructive form of corrosion posing devastating threat to refining equipment integrity and safety of refinery process. Ammonium chloride forms an underdeposit corrosion mostly experienced in the overhead equipment and piping for crude and hydroprocessing units causing severe fouling and damages that posed negative impact on the operating reliability of various processing units. This work addresses the corrosion mechanism caused by ammonium chloride and its inhibition against Hydrochloric acid using Carbon steel. Weight loss analysis and polarization was used to study the inhibition efficiency and corrosion rate of the samples in 0.5M HCl, 1.0M HCl, 20% NH4Cl and 30% NH4Cl solution. The average inhibition efficiency and corrosion rate for 0mL, 2mL, 4mL, 6mL, 8mL, and 10mL of Neem Oil in 0.5M HCl, 1.0M HCl, 20% NH4Cl, and 30% NH4Cl solutions were determined. Result showed that Neem Oil Extract was effective in both HCl and NH4Cl solution on Carbon steel. Inhibition efficiency of each samples increases with Neem Oil concentration while the corrosion rate decreases with concentration