The inhibition potency of expired thiamine or vitamin B1 (VB1) and riboflavin or vitamin B2 (VB2) against SABIC iron corrosion in 0.5 M H2SO4 solutions was investigated using chemical and electrochemical techniques.

Top and side views for adsorption of the two dimers over Fe (110) surface.

This work focuses on the use of natural parsley oil as a safe, eco-friendly and cost-effective inhibitor for dissolution of X80 carbon steel (X80CS) in 0.5 M H2SO4 solution.

Two pyrazole derivatives, namely 2,4-diamino-5-(5-amino-3-hydroxy-1H-pyrazole-1-carbonyl)thiophene-3-carbonitrile (I) and 1-(2,4-diamino-5-(5-amino-3-hydroxy-1H-pyrazole-1-carbonyl)thiophen-3-yl)propan-1-one (II) were evaluated as a corrosion inhibitors for carbon steel in 1M hydrochloric acid by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy methods. Spectrophotometric and conductometric titration methods were also utilized to investigate the possibilities of chemical adsorption between the steel surface and the compounds under consideration. The results showed that the studied compounds inhibit the corrosion of steel in acidic solution at different temperatures. The adsorption followed the Langmuir isotherm. The thermodynamic and the activation parameters were also determined and discussed.