Experimental and Theoretical Studies of (2R)-5-hydroxy-7- methoxy-2-phenyl-2,3-dihydrochromen-4-one as corrosion inhibitor for Iron in Hydrochloric Acid

摘要

The corrosion inhibition on the iron surfaces by (2R)-5-hydroxy-7-methoxy-2-phenyl-2,3-dihydrochromen-4-one (PN), isolated from Kaempferia pandurata Roxb, has been conducted bothexperimentally and theoretically. The corrosion inhibition effectiveness of PN was studied bygravimetric and electrochemical experiments and density function calculation at B3LYP level oftheory. The PN successful isolation was confirmed by spectroscopic techniques.The presence of aninhibitor can effectively inhibit iron corrosion in 1M HCl. The adsorption of PN on the iron surfaceobeyed the Temkin adsorption and physisorption mechanism. The effect of electron donating andwithdrawing groups on the inhibition efficiency was studied by density functional theory method. Theinhibition efficiency of PN increased with the addition of the N-NH 2 function group whereas the NO 2group gave the opposite result.