Available materials for petrochemical transfer pumps using nitric acid/sulfuric acid/hydrochloric acid/phosphoric acid/hydrofluoric acid/caustic soda/soda ash

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General characteristics of nitric acid (HNO3): It is an oxidizing medium. The operating temperature for concentrated HNO3 is generally below 40°C. Elements Cr and Si confer oxidation resistance, and stainless steels as well as other materials containing Cr and Si are ideal materials for resisting corrosion in concentrated HNO3. Therefore, the material commonly chosen for nitric acid transfer pumps is high-silicon cast iron (STSi15R): for all temperatures below 93% ； High-chromium cast iron (Cr28): all temperatures below 80% ； Stainless steel (SUS304, SUS316, SUS316L): All temperatures below 80% ； S-05 steel (0Cr13Ni7Si4): all temperatures below 98% ； Industrial pure titanium (TA1, TA2): all temperatures below the boiling point (except at high temperatures where smoking occurs) ； Industrial pure aluminum (Al): all temperatures at room temperature (only for containers) ； CD-4MCu age-hardening alloy: all temperatures below the boiling point ； Materials such as Hastelloy C, gold, and tantalum all possess excellent corrosion resistance. 　 General properties of sulfuric acid (H2SO4): the boiling point increases as the concentration rises. For example: a concentration of 5% results in a boiling point of 101 ℃ ； With a concentration of 50%, its boiling point is 124℃ ； The concentration is 98%, and its boiling point is 332°C. Concentrations below 75% are reducing (or neutral), while those above 75% are oxidizing. Therefore, the materials commonly chosen for sulfuric acid transfer pumps are stainless steel (SUS316, SUS316L): for temperatures below 40 ℃ and concentrations of around 20% ； 904 steel (SUS904, SUS904L): Suitable for temperatures of 40–60 °C and concentrations of 20–75% ； Temperature 80 ℃, concentration below 60% ； High-silicon cast iron (STSi15R): various concentrations from room temperature to 90 °C ； Pure lead, hard lead: various temperatures at room temperature ； S-05 Steel (0Cr13Ni7Si4): Concentrated sulfuric acid at temperatures below 90 ℃, and high-temperature concentrated sulfuric acid (120–150 ℃) ； Plain carbon steel: concentrated sulfuric acid at over 70% at room temperature ； Cast iron: concentrated sulfuric acid at room temperature ； Monel, metallic nickel, Inconel: sulfuric acid at moderate temperature and concentration ； Titanium-molybdenum alloy (Ti-32Mo): below the boiling point in 60% sulfuric acid, and below 50 °C in 98% sulfuric acid ； Hastelloy B, D: below 100 ℃, 75% sulfuric acid ； Hastelloy C: Various temperatures around 100 ℃ ； Nickel cast iron (STNiCr202): 60~90% sulfuric acid at room temperature. 　 General properties of hydrochloric acid (HCl): It is a reducing medium, with a maximum temperature of 36–37%. Boiling point: At a concentration of 20%, it is 110 ℃ ； When the concentration is between 20% and 36%, it is 50℃ ； Therefore, the maximum temperature for hydrochloric acid is 50 ℃. Therefore, the material commonly chosen for hydrochloric acid transfer pumps is metal tantalum (Ta): it is the most ideal corrosion-resistant material for hydrochloric acid, but it is expensive and is often used in metering devices where precision is required ； Hastelloy B: hydrochloric acid at a temperature of ≤ 50 ℃ and a concentration of 36% ； Titanium-molybdenum alloy (Ti-32Mo): all temperatures and all concentrations ； Nickel-molybdenum alloy (Ch1orimetz, 0Ni62Mo32Fe3): all temperatures and all concentrations ； Industrial pure titanium (TA1, TA2): hydrochloric acid at 10% or less at room temperature ； ZXSNM(L) alloy (00Ni70Mo28Fe2): hydrochloric acid at 50 ℃ and 36% concentration ；