Investigation of Polyvinyl Alcohol Corrosion Inhibitor for Aluminum in Sulfuric Acid

Abstract

Corrosion mitigation remains a critical challenge in industries utilizing aluminium (Al), particularly in acidic environments where material degradation can compromise structural integrity and operational efficiency. The effectiveness of Polyvinyl Alcohol (PVA) as a corrosion inhibitor for Al in 1 M sulfuric acid (H₂SO₄) was evaluated through weight loss and polarization techniques. The study was conducted at three different temperatures (25 °C, 35 °C, and 45 °C) and varying concentrations of PVA (300, 450, and 600 ppm) to assess its inhibition efficiency. Results indicated that the inhibition efficiency increased with higher PVA concentrations, achieving maximum values of 90%, 88%, and 86% at 600 ppm for the respective temperatures. However, inhibition efficiency was found to decrease slightly with increasing temperature. Polarization studies revealed that PVA acted as a mixed-type inhibitor, reducing both anodic and cathodic currents. The maximum inhibition efficiency at 25°C was 91% as determined by polarization, with a corresponding reduction in corrosion current from 264.12 mA/cm² (blank) to 23.08 mA/cm² at 600 ppm. The study demonstrates the potential of PVA as an eco-friendly corrosion inhibitor for Al in acidic environments, as its performance is significantly influenced by both temperature and concentration.