Exploration of furan derivative for application as corrosion inhibitor for mild steel in hydrochloric acid solution: Effect of immersion time and temperature on efficiency

Abstract

The possibility of using 2-(5-amino-1,3,4-oxadiazol-2-yl)-5-nitrofuran as a corrosion inhibitor for mild steel in hydrochloric acid solution was explore utilizing weight loss complemented with surface characterization through scanning electron microscopy (SEM) techniques. The effect of time and temperature on the inhibition efficiency of 2-(5-amino-1,3,4-oxadiazol-2-yl)-5-nitrofuran was also investigated. Results from weight loss techniques imply that 2-(5-amino-1,3,4-oxadiazol-2-yl)-5-nitrofuran demonstrate significant anticorrosion characteristics toward mild steel dissolution in 1 M hydrochloric acid environment. The 2-(5-amino-1,3,4-oxadiazol-2-yl)-5-nitrofuran showed the highest inhibition efficiency of 79.49% at the highest inhibitor concentration of 0.005 M studied, for the immersion time of 5 h and a temperature of 303 K from gravimetric result. Inhibition efficiency of 2-(5-amino-1,3,4-oxadiazol-2-yl)-5-nitrofuran differs directly with immersion time or temperature. A decrease in inhibition efficiency with an increase in temperature is implied to the physisorption mechanism and may be imputed to increase in the solubility of the precipitated inhibitor molecules on the mild steel surface. The number of adsorbed molecules on mild steel surface decreases regarding the temperature increases which resulted in a deficiency in inhibitive performance. The kinetic studies indicate that the adsorption of tested inhibitor on the surface of mild steel both physical adsorption and chemical adsorption. Surface characteristic findings confirm the presence of 2-(5-amino-1,3,4-oxadiazol-2-yl)-5-nitrofuran on the tested mild steel surface. 2-(5-Amino-1,3,4-oxadiazol-2-yl)-5-nitrofuran follows the Langmuir adsorption isotherm.