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Summary: 1. When using 316L and the concentration is below 5%, the operating temperature should preferably not exceed 50 degrees Celsius; if such high temperatures are necessary, 904L can be considered, with an estimated corrosion rate of 1.14 mm/year； 2. In sulfuric acid at around 1%, at 80 degrees Celsius, the corrosion rate of 2316L is approximately 0.3 mm/year. However, if the concentration increases slightly or the temperature rises further, the corrosion rate increases significantly; in acid with a concentration of around 2%, the corrosion rate at the boiling point is close to 1 mm/year. Given your operating conditions, which are at a critical level, severe corrosion may occur if the local acid concentration is too high. Therefore, it is best not to use this material ； 3. Sulfuric acid at different concentrations and temperatures causes varying degrees of corrosion to materials. For concentrated sulfuric acid with a concentration of over 80% and a temperature below 80°C, carbon steel and cast iron exhibit good corrosion resistance; however, it is not suitable for sulfuric acid that flows at high speeds, and thus cannot be used as material for pumps and valves ； Common stainless steels such as 304 (0Cr18Ni9) and 316 (0Cr18Ni12Mo2Ti) also have limited utility in sulfuric acid media. Therefore, pump valves for transporting sulfuric acid are typically made of high-silicon cast iron (which is difficult to cast and process) or highly alloyed stainless steel (grade 20 alloy). Fluoroplastics exhibit good resistance to sulfuric acid, making the use of fluorinated pump and valve materials (F46) a more economical option. If the pressure is too high and the temperature rises, the performance of the plastic valve is affected, and in such cases one has to opt for a ceramic ball valve, which is much more expensive. Therefore, pump valves used for transporting sulfuric acid are typically made of high-silicon cast iron (which is difficult to cast and process) or highly alloyed stainless steel (grade 20 alloy); it is recommended to use grade 20 alloy, as this material is specifically designed for use with sulfuric acid! 4. Other suggestions: 2205 duplex steel is fully suitable and offers good cost-performance ； Phenolic resin can be used to make fiberglass reinforced plastic, and temperature is not a major issue ； 5. When selecting relevant valves, it is recommended to use fluoroplastic valves or 20 alloy valves ； If the pressure is not high, PP or UPVC ball valves or diaphragm valves can be used. I hope everyone will continue to research it thoroughly.