Effect of refrigerant absorbent combinations in the corrosion resistance of copper as structural material in absorption refrigeration systems (ARS)

ABSTRACT

The present research was focused on analyzing the corrosion resistance of copper in the presence of refrigerant-absorbent combinations such as lithium bromide (LiBr), lithium nitrate (LiNO₃) and calcium chloride (CaCl₂), used in Adsorption Refrigeration Systems (ARS). Electrochemical techniques such as open circuit potential, electrochemical impedance spectroscopy, electrochemical noise analyses and potentiodynamic polarisation curves were applied to study the test solution combination effect on the corrosion rate of copper as a structural material in ARS. OCP analyses reveal that the E_corr shifted based on the temperature and test solution. Meanwhile, when the copper was immersed in LiBr/H₂O + CaCl₂ at 80°C, the corrosion current density (I_corr) was lower (0.003 mA/cm²). Also, The R_p estimated from EIS shows an increase at 80°C. Micrographs of the copper surface immersed in LiBr/H₂O and LiBr + CaCl₂ observed cracks and pits. But also, when the corrosion product layer was removed, a less heterogeneous surface was revealed.

GRAPHICAL ABSTRACT

KEYWORDS:

• Corrosion
• adsorption refrigeration systems (ARS)
• copper
• absorbent compounds mixture

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data supporting this study’s findings are available from the corresponding author upon reasonable request.