Monopropylene glycol based heat transfer fluid: effects of green and synthetic corrosion inhibitors on copper and aluminum with ageing tests

Abstract

Purpose The purpose of this paper is to understand corrosion behavior of copper and aluminum in monopropylene glycol-based heat transfer fluid by using synthetic and green inhibitors. Design/methodology/approach Weight loss, potentiodynamic and impedance measurements were applied to specimens to obtain their electrochemical characteristics and corrosion behaviors. Ageing test was applied to the fluids that contain different corrosion inhibitors to see the effect of inhibitors on fluid structure, and surface morphologies were examined by scanning electron microscopy (SEM). Findings The corrosion tests showed that synthetic inhibitors have better anti-corrosion potential than green inhibitors. Social implications Like the synthetic corrosion inhibitors, there is growing interest in green inhibitors. Synthetic corrosion inhibitors are expensive and toxic for live beings, but green inhibitors from naturel sources are easy to reach and non-toxic for live beings and environment. Originality/value For solar heating systems, there is a need to select the correct heat transfer fluid; corrosion behavior of fluid plays a major role in the operation because the big part of the heating system consists of copper and aluminum close to ferrius metals and stainless steel.