Evaluation of Corrosion Effects in Diesel-Biodiesel and Diesel-Biodiesel-HVO Blends on Metals for Fuel Storage Systems

Indonesia has implemented B35, as a mixture of 35% biodiesel and 65% diesel fuel. Considering the potential of higher biodiesel blends, it is important to explore the use of hydrotreated vegetable oil (HVO) in fuel blends. HVO can improve cetane number, heating value, sulfur content, and oxidation stability. However, further research is needed, particularly regarding compatibility of materials used in storage and distribution systems. Common materials include stainless steel, carbon steel, and brass. This study aimed to assess effects different fuel mixtures on corrosion rates of stainless steel 304, carbon steel SA 516 Gr.70, and brass immersed in B30, B30D10 (30% biodiesel, 60% diesel fuel, and 10% HVO), and B40. Corrosion rates were tested using ASTM G31 over 2160 hours at room temperature. Results showed that stainless steel 304 had the lowest corrosion rate, followed by carbon steel SA 516 Gr.70 and brass. However, brass led to fuel degradation, notably in cleanliness, water content, and oxidation stability, making it unsuitable for storing diesel-biodiesel and diesel-biodiesel-HVO blends. HVO positively influenced biodiesel- diesel blends, resembling diesel fuel and reducing total acid number and water content, thus lowering corrosion rates of metals.