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Abstract The corrosive character of Moringa oleifera Lam biodiesel was evaluated through static immersion tests with different carbon steels (CS1015 and CS4140) in absence and presence of the antioxidant tert-butylhydroquinone (TBHQ), at room temperature in the absence of light for 84 days. Biodiesel parameters, including oxidation stability (induction period, IP), total acid number (TAN) and iron concentration released from carbon steel, were monitored. The produced biodiesel presented an IP value of 4.9 h, which was increased to 6.2 h after the addition of 500 mg kg−1 TBHQ. After 84 days of immersion, IP values decreased in the first 21 days due to the contact with the metallic coupon, while TBHQ retarded this process. TAN value increased in 20% but the values were below the recommended limits (<0.5 mg g−1 KOH according to EN14214). Iron was detected in the biodiesels exposed to CS1015 (8 μg g−1), while in the presence of TBHQ this value decreased to 5 μg g−1, indicating corrosion inhibition by TBHQ. Iron was not detected in the biodiesels exposed to CS4140, which indicated that this material was more compatible with biodiesel. Notably, the oxidation stability of Moringa biodiesel was not affected (IP > 3 h) by the high Fe content. Highlights • Static immersion corrosion test to simulate storage conditions of Moringa biodiesel. • Carbon steels of varied composition were evaluated and metal release measured. • Oxidation stability of biodiesel decreased as corrosion started. • The antioxidant TBHQ retarded the corrosion as iron release decreased. • Addition of TBHQ is required to extend storage stability of Moringa biodiesel. [ABSTRACT FROM AUTHOR]