Use of Time Domain Nuclear Magnetic Resonance Relaxometry to Monitor the Effect of Magnetic Field on the Copper Corrosion Rate in Real Time

Author(s)

Nascimento Mitre, Cirlei Igreja ; Gomes, Bruna Ferreira ; Paris, Elaine ; Silva Lobo, Carlos Manuel ; Roth, Christina ; Colnago, Luiz Alberto

• Document type: Journal article
• Source: MAGNETOCHEMISTRY; v. 8, n. 4, p. 10-pg., 2022-04-01.

Abstract

The corrosion of metals is a major problem of modern societies, demanding new technologies and studies to understand and minimize it. Here we evaluated the effect of a magnetic field (B) on the corrosion of copper in aqueous HCl solution under open circuit potential. The corrosion product, Cu2+, is a paramagnetic ion and its concentration in the solution was determined in real time in the corrosion cell by time-domain NMR relaxometry. The results show that the magnetic field (B = 0.23 T) of the time-domain NMR instrument reduces the corrosion rate by almost 50%, in comparison to when the corrosion reaction is performed in the absence of B. Atomic force microscopy and X-ray diffraction results of the analysis of the corroded surfaces reveal a detectable CuCl phase and an altered morphology when B is present. The protective effect of B was explained by magnetic forces that maintain the Cu2+ in the solution/metal interface for a longer time, hindering the arrival of the new corrosive agents, and leading to the formation of a CuCl phase, which may contribute to the rougher surface. The time-domain NMR method proved to be useful to study the effect of B in the corrosion of other metals or other corrosive liquid media when the reactions produce or consume paramagnetic ions. (AU)

• FAPESP's process: 21/12694-3 - Applications of NMR and infrared spectroscopies in the non-destructive analysis of products and agroindustrial processes
• Grantee: Luiz Alberto Colnago
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/13656-8 - Development and application of nuclear magnetic resonance in products and agricultural processes
• Grantee: Luiz Alberto Colnago
• Support Opportunities: Regular Research Grants
• FAPESP's process: 12/22281-9 - NMR study of the magneto-convective phenomenon on paramagnetic ions during electrodeposition
• Grantee: Bruna Ferreira Gomes Lobo
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)