Corrosion inhibition of carbon steel on hydrochloric acid using zizyphus spina-chritisi extract

Abstract EN

Naturally occurring substances are increasingly being tried to used as corrosion inhibitors of metals in acid cleaning processes to replace some toxic and expensive chemicals currently in use.

The corrosion inhibition of carbon steel in hydrochloric acid by Zizyphus Spina–Chritis leaves extract was studied using weight loss techniques.

Maximum inhibition efficiency and surface coverage were obtained at an optimum concentration.

However, an increase in temperature lead to decreased in the inhibition efficiency at the temperature studied.

Optimum inhibition efficiency for carbon steel in the presence of Zizyphus Spina–Chritis leaves extract was 99.5%, 75% and 66% at 1 %,1 %and 2 % concentration of the inhibitor at 25oC, 35oC and 45oC respectively.

The phenomenon of physical adsorption has been proposed from the activation energy values (55.66KJmol-1).

The surface coverage (θ) data augment the above observation and the inhibition is attributed to the physical adsorption of the chemical components of the additive on the surface of the carbon steel.

Inexpensive environmentally safe inhibitor formulations indicate have been obtained.