Keywords : Carbon Steel
journal of kerbala university,
2007, Volume 3, Issue 3, Pages 196-207
The present study is attempted to find new inhibitors that can to easily be prepared and applied, as well as nontoxic, cheap and available. In this study hibiscus leaves extractor was used to protect carbon steel in hydrochloric acid solution (1M, 2M, and 3M). Since the usable inhibitor is considered organic inhibitor, and for evaluating the inhibition performance of this compound, many tests have been conducted which include measuring the corrosion rate through methods known weight loss and microscopic examination test. In losing weight method the inhibitor gives good efficiency in protecting, the carbon steel to be corroded at 1M HCl is 77% while the efficiency is drop to 68% in 3 M HCl at 30 oC. Microscopic examination test shows the clearness of the metals surface which is under the corrosion medium and which contains inhibitor, from any kind of corrosion that can be found on those surface, which are under mediums completely empty from inhibitor, and also shows the clearness of that protect layer on the surface. The data of corrosion rate show that the way of doing this organic inhibitor is adsorbing and the inhibitor molecules are adsorbed on the metal surface according to Langmuir adsorption isotherm.