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Filter construction for citric and sulfamic acid

We have been asked to build a system that will filter a mixture of citric and sulfamic acid. We have not been given pH-levels that will be used, but I would like to know if there are any dangers of mixing the two acids and if it will corrode carbon steel, 316 and 304 Stainless Steels. This mixture will be specifically used to clean carbon steel piping on a ship and our system will be manufactured out of either 304 stainless or 316 stainless steel. The cleaning will be done at a ship building facility.

Thank you.

Alejandro Alvarado
filtration manufacturer - Boerne, Texas, United States
2004

Temperature will have as much an effect on the etch rate as pH will (within reason). My personal preference would be to make all equipment that comes in contact with the acid out of 316L SS or a good grade of plastic. Plastic choice will have more to do with temperature than with pH.

James Watts
- Navarre, Florida
2004