When storing a chemical, it’s critical that you are confident that your entire tank system is compatible with the chemical and up to the task of providing safe storage. To help customers understand the compatibility of specific chemicals with our polyethylene tanks and accessories, we created our chemical resistance chart. Using this resource, you can see the compatibility of our tanks, fittings, and gaskets with over 100 different chemicals.
In order to make an informed decision on which options will work with a specific chemical, it’s important that you understand how to read the chemical resistance chart. Let’s go through the process of using the chart with an example chemical, sodium hypochlorite.
Understanding The Chemical Resistance Chart
We always recommend starting with the chemical being stored and this is no exception. Choose a chemical from the dropdown and you’ll be presented with a list of categories running horizontally across the top of the table.
From left to right, our table lists the following information about the chemical:
- Chemical name
- Chemical formula
- Chemical concentration
- Tank specific gravity required to safely store the chemical at its given concentration
For the rest of the chart, compatibility is noted as satisfactory (marked with an S) or unsatisfactory (marked with a U).
First, the ratings for our two tank material options, high-density cross-linked polyethylene (XLPE) and high-density linear polyethylene (HDPE), are shown at various temperatures. The XLPE has been tested at 100° and 140°F and our linear polyethylene at 70° and 140°F. Many of the more corrosive and potentially dangerous chemicals cannot be held in linear polyethylene tanks, especially at higher temperatures.
Using our example of sodium hypochlorite, you can see that the formula is NaOCI and that the specific gravity of a tank storing this chemical at 0.8% or 9% to 15% must be at least 1.2. We can store this chemical in XLPE tanks at any temperature, but higher concentrations (9-15%) cannot be stored in linear polyethylene (HDPE) tanks.
Fittings and Gaskets
From there, you can see whether the various types of fittings (columns PVC-Alloy 400) and gaskets (columns VITON® - NEOPRENE®) that we offer.
For example, you can see that a chemical storage tank holding sodium hypochlorite at 0.8% concentration is compatible with all types of fittings except for stainless steel, and all types of gaskets except for those of alloy 400, made of buna, and/or neoprene. The last box in the row contains any special notes or comments that should be considered when storing the chemical.
Creating Our Chemical Resistance Chart
All of the information that we use in our chemical resistance chart comes from respected industry standards including the Philip A. Schweitzer Corrosion Resistance Tables published by Marcel Dekker, as well as Kenneth M. Pruett’s Chemical Resistance Guide, by Compass Publications.
We verify all data in the resistance chart against these industry standards to ensure we deliver accurate recommendations for chemical storage.