Azorhodanine derivatives as inhibitors for acidic corrosion of nickel.
Azorhodanine derivatives (HL1-HL5) were tested as corrosion inhibitors for nickel in 2M HNO3 solution using weight loss and galvanostatic polarization techniques. The results showed that these derivatives act as inhibitors for nickel in this medium. The inhibition was assumed to occur via adsorption of the inhibitor molecule on the metal surface. Polarization measurements indicated that these compounds act as mixed-type inhibitors, but the cathode is more polarized when an external current was applied. This means that these compounds retard the rate of hydrogen evolution and the rate of dissolution of the metal. Results showed that azorhodanine derivatives are adsorbed on the nickel surface following Temkin's adsorption isotherm. The activation energy and thermodynamic parameters were calculated and discussed at different temperatures (30-45 degrees C).
Fouda
Abd El-Aziz S
Ael-A
Department of Chemistry, Faculty of Science, El-Mansoura University, El-Mansoura 35516, Egypt. asfouda@yahoo.com
Al-Sarawy
Ahmed A
AA
Omar
Tark M
TM
D001391:Azo Compounds / Q000737:chemistry*; D003343:Corrosion; D006358:Hot Temperature; D008956:Models, Chemical; D009532:Nickel / Q000737:chemistry*; D017942:Nitric Acid / Q000737:chemistry*; D012236:Rhodanine / Q000737:chemistry*; D013997:Time Factors
D001391:Azo Compounds; D017942:Nitric Acid; D012236:Rhodanine; D009532:Nickel