Experimental and theoretical studies of media effects on copper corrosion in acidic environments containing 2-amino-5-mercapto-1,3,4-thiadiazole

Abstract

Corrosion behaviour of copper metal in acid solutions (HCl, H 2 SO 4 and H 3 PO 4 ) containing 2-amino-5-mercapto-1,3,4-thiadiazole (AMT) was investigated experimentally and theoretically via gravimetric, potentio-dynamic and quantum electrochemical approaches. Similar behavior was observed for H 2 SO 4 and H 3 PO 4 media, and related to the nature of anions at metal/solution interface. With regard to HCl, however, the rate of corrosion was determined to be low at initial stages, but high later on using an auto-catalyzing mechanism. In the presence of AMT, the experimental studies revealed that this molecule was a good anodic-type inhibitor causing substantial changes in corrosion potential. Moreover, its adsorption obeys the Langmuir isotherm. The values of ǻG ads were determined and correlated to the inhibitor powers. Finally, the influence of media (anions) on metal corrosion was also investigated from molecular point of view by calculations of the copper-anions interaction using density functional theory.

Inhibition of Acid Corrosion of Mild Steel Using <i>Delonix regia </i>Leaves Extract

“…The results obtained show that the rate of mild steel dissolution in 0.5 M H 2 SO 4 is higher than that in 1 M HCl, which is in agreement with previous reports [26,27]. The differences in the polarization profiles in 1 M HCl and .5 M H 2 SO 4 solutions possibly suggest that the acid anions influenced the processes in different ways.…”

Experimental Investigation of the Inhibiting Action of Adenine on the Corrosion of Mild Steel in Acidic Environments

“…The results obtained show that AD manifested a higher inhibiting effect on mild steel in HCl at 30°C and in H 2 SO 4 at 60°C . This is an evidence that the degree of protonation as well as nature of the acid anions influence the corrosion process (Lashgari et al, 2010;Oguzie, 2008).…”

“…It is well known that the type of corrodent and metal, temperature of the understudy system as well as concentration and molecular structure of an inhibitor, are important factors for consideration in assessing the effectiveness of an inhibitor (Lashgari et al, 2010;Khaled, 2010;Oguzie, 2008;Eddy et al, 2010). The present study investigates the effect of type of acid anions on the corrosion inhibition potential of adenine in hydrochloric and sulphuric acid solutions.…”

Theoretical and experimental investigations on corrosion control of 65Cu–35Zn brass in nitric acid by two thiophenol derivatives

“…Among methods which have been applied to minimize the dezincification phenomenon, the use of inhibitors is most efficient one. In this way, many types of organic and inorganic chemical compounds have been introduced as the corrosion inhibitor for copper and its alloys [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. The inhibition mechanism is generally explained that inhibitor molecules which are able to donate electrons, form coordinative bonds in the presence of vacant d-orbitals in copper [5].…”