Synthesis , Identification and Study of Some New Schiff Bases as Inhibitors for Brass Corrosion

Abstract

Three Schiff bases were synthesized namely (4-dimethyl amino benzaldene – 3-amino benzoic acid ) , ( piperonaldene – 4-amino – 2-nitro toluene ) and (4-dimethyl amino benzaldene - 4-amino – 2-nitro toluene ) . These Schiff bases have been identified by microanalysis ( CHN ) , infrared , 1H-NMR , 13C-NMR and GC-Mass spectroscopy . The study also included the use of these Schiff bases as inhibitors for corrosion of brass in acidic media ( 0.5 M HCl ) . The rate of corrosion was determined by two methods ( electrochemical and weight loss methods ) . It was found agreement between them . Different studies such as ; the effect of temperature on the corrosion rate at ( 298 ˚K , 308 ˚K and 318 ˚K ) , measurement of some thermodynamic parameters ( corrosion current , activation energy and free energy ) , and comparison of inhibition effect for prepared Schiff bases with their primary amines were achieved . The results indicated that these Schiff bases inhibited the corrosion efficiently . Furthermore , antibacterial activity of prepared Schiff bases and standard inhibitor (AK3) was also studied on the two types of bacteria ,Staphylococcus aureus and Escherichia coli . It was found that the Schiff bases under study were considered inhibitors for bacterial growth with variation extents .