Which pair of metal storage tanks for naphtha and gasoline is severely corroded?

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Naphtha is more corrosive to metal storage tanks than gasoline. Naphtha, as an intermediate product in the oil refining process, usually contains high levels of hydrogen sulfide and active sulfides, especially naphtha that has not been desulfurized, which is more corrosive. These active sulfur components can directly react electrochemically with metals, causing pitting corrosion, pitting corrosion and even perforation on the inner wall of the storage tank, seriously threatening the safe operation of the storage tank. In contrast, although gasoline is also corrosive, mainly due to the mercaptans, organic acids and moisture in it, the finished gasoline has been refined and the sulfur content has been greatly reduced (the national standard requires sulfur content ≤10 mg/kg), and anti-corrosion agents have been added, so the overall corrosiveness is weak. From the perspective of the corrosion parts of the storage tank, both the tank bottom plate and the gas-liquid interface are the key corrosion areas. However, due to the high sulfur content of the naphtha storage tank, the corrosion rate is faster and the damage is more concentrated, especially in the welding heat-affected zone and depressions, which are prone to ulcer-like corrosion.