When fully concentrated, nitric acid (HNO3) is a clear acid with a sharp, pungent odor. It is a common, yet highly corrosive, acid that is used for a number of purposes.
If you are working with a versatile, corrosive substance like nitric acid, it is important that you find a suitable storage solution.
To learn more about storing this particular acid, let’s look at some common uses for nitric acid, and how best to store this substance.
Nitric Acid Uses
Nitric acid is most commonly seen in the production of fertilizers for plants and grass, as it neutralizers with ammonia to form ammonium nitrate. While normally clear, nitric acid turns into a brownish-yellowish solution when decomposed in water, nitrogen dioxide, and oxygen.
Other uses for nitric acid include woodworking, rocket propulsion, metal finishing, and sanitizing. The highly corrosive and oxidizing acid can also be used for dyes and certain kinds of explosives, since nitric acid can produce potentially explosive hydrogen gas when combined with some common metals.
It is clear to see that nitric acid can be a dangerous chemical in use. Storing this chemical can be just as dangerous if it is not done properly.
Nitric Acid Storage Recommendations
With all acids, the concentration of the solution often determines the limitations of storage solutions. The stronger the concentration, the more careful you must be with the chemical.
At Poly Processing Company, our chemical storage tanks can hold concentrations of nitric acid up to 49%. If your concentration falls between 0 and 29%, it can be stored in a more robust high-density cross-linked polyethylene (XLPE) tank or a linear polyethylene tank in smaller sizes. Any of our stainless steel, titanium, or PVC fittings will work for storing nitric acid, but we do not use alloy 400 fittings or gaskets made out of buna, EPDM, or neoprene because of the potential for corrosion.
For nitric acid with a concentration of between 30 and 49%, we use strictly our XLPE tanks, as we have found that they have several advantages over tanks made with linear polyethylene. Storing these stronger concentrations should not be done at temperatures above 100° F. Our guidelines for fittings and gaskets are the same as they are for nitric acid with a concentration of between 0 and 29%, except alloy 400 can be used for the bolts on tank fittings used to store this higher concentration of nitric acid.
Our Approach to Nitric Acid Storage
All of our guidelines for the storage of nitric acid are based on several industry standards from leading publications. We have carefully checked our chemical resistance chart against these resources to ensure that it is as accurate as possible.