Sodium nitrite as a corrosion inhibitor of copper in simulated cooling water

Abstract

The corrosion inhibition behavior of sodium nitrite (NaNO2) towards pure copper (99.95%) in simulated cooling water (SCW) was investigated by means of electrochemical impedance spectroscopy (EIS) and dynamic electrochemical impedance spectroscopy (DEIS). NaNO2 interferes with metal dissolution and reduce the corrosion rate through the formation or maintenance of inhibitive film on the metal surface. Surface morphologies illustrated that the surface homogeneity increased on adding sodium nitrite. Sodium nitrite’s adsorption on copper surface followed the modified form of Langmuir, Freundlich and Frumkin isotherms. Physiosorption mode was involved in the corrosion protection. Electrochemical results revealed an corrosion resistance of copper increases on increasing the inhibitor concentration. The DEIS results indicated that copper corrosion mechanism could be hindered by 50% even after interval of 24 h by optimum concentration of sodium nitrite. The maximum inhibition was achieved with 2000 ppm of NaNO2. With this concentration, inhibition efficiency of up to 61.8% was achievable.

Green inhibitor of carbon steel corrosion in 1 M hydrochloric acid:Eruca sativaseed extract (experimental and theoretical studies)

“…This one was confirmed in this investigation, which revealed that the equilibrium constant was significantly higher than in earlier studies. 100,101 Langmuir isotherms were found to provide a better explanation for the adsorption method of Eruca sativa seed extract on the carbon steel surface than Henry due to the precision of R 2 . The Gibbs free energy adsorption values are intended using eqn (17). K ads = 1/55.5 exp(Δ G 0 ads / RT )…”

Investigation of the Effect of Deep Cryogenic Treatment with Different Holding Time on the Corrosion Behavior of Cementation Steel

“…Belirlenen frekans aralığına bağlı olarak bir sistemin empedansını ölçmek için kullanılan bir elektrokimyasal tekniktir [15]. Sistem ara yüzünde meydana gelen elektrokimyasal etkileşim uygun devre modeli aracılığıyla simule edip hesaplanmaktadır [16]. İncelenen sistem ara yüzünde meydana gelen elektrokimyasal süreçlerin fiziksel temsili olan pasif elektrik bileşenleri (yani dirençler R, kapasitörler C ve endüktanslar L) hesaplanabilmektedir.…”

Investigation of the Inhibition Mechanism of Organic Corrosion Inhibitors on the Copper Surface by DFT study and MD simulations

“…Currently, various corrosion inhibitors, which are divided into organic and inorganic corrosion inhibitors, have been investigated globally [1b,5] . Inorganic corrosion inhibitors are classified into four types based on their extensive use, diversity, and ability to complete current processes: nitrite corrosion inhibitors, [6] chromate corrosion inhibitors, [7] molybdenum salts, [8] and tungstate corrosion inhibitors [9] . Organic corrosion inhibitors with green environmental protection, less dosage, and mature research, are mainly divided as azole compounds, [10] amines, [11] amino acids, [12] triphenylmethane derivatives, sulfhydryl compounds, phosphates, and other organic compounds [13] .…”