Original Articles: 2013 Vol: 5 Issue: 12
Effect of Lavandula stoechas oil on welded material corrosion in 5.5M H3PO4 solution
Abstract
Due to problems of resistance to corrosion, the activity of essential oils has now experienced a great revival. Study of the essential oil of the plant Lavandula stoechas was studied in 2012 in Doukkala area with relation to the agricultural. The results show that the level of the oil extracted there is a majority molecule (L-fenchone) with a percentage of 26 via CPG coupled with MS. The influence of phosphate of organic oil of leaves of Lavandula stoechas [L] on the corrosion inhibition of welded material in phosphoric acid solution was studied using the weight-loss method. The electrochemical performance of the inhibitor was also investigated through potentiodynamic polarization. The inhibition efficiency of inhibitor increases with concentration to attain 89 % at 1.2 g.L-1 of [L] in the phosphoric acid (40 wt. %) or 5.5M H3PO4 with the addition of chemical impurities (4 wt. % of H2SO4 and 0.04 wt. % of chloride ions used as KCl). Polarization studies show that [L] is an anodic-type inhibitor and acts the anodic reactions. The inhibition efficiency of [L] is temperature-dependent in the range 298 - 363 K, the associated activation energy has been determined. [L] Adsorbs on the welded material surface according to a Langmuir isotherm adsorption model