查看更多>>摘要:Cerium tartrate(CeTar),produced in this study by precipitating cerium nitrate with potassium sodium tartrate(KNaTar),was examined as a corrosion inhibitor.Weight loss tests show inhibition efficiency of 71.7%with Ce(NO3)3 and 88.7%with CeTar inhibitor for one-month exposure to mild steel in 7 g/L NaCl solution.The inhibition efficiency drops to 28.6%with the former and remains around 87%with the latter inhibitor after six months of exposure.Similar results from electrochemical testing indicate that the inhibition efficiency decreases by adding cerium nitrate.Still,the cerium tartrate inhibitor demonstrates a nearly constant inhibition efficiency for up to 30 d,i.e.,≈ 90%.Electrochemical impedance spectroscopy(EIS)performed in these cases shows the following results:(ⅰ)with cerium nitrate,a film of iron and cerium oxide,which on prolonged exposure diminishes,and(ⅱ)with cerium tartrate,the formation of a bimetallic film(Fe-tartrate-Ce)and a mixture of cerium hydroxide and iron oxide that protects steel for a longer duration.These inferences are based on the analyses of scanning electron microscopy/energy-dispersive X-ray analysis(SEM/EDAX),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron(XPS),and Raman spectroscopy results.