Chemical Compatibility Chart

Compatibility ratings for 1,460 chemicals and 26 pump materials. Search for the fluid you will be pumping, and evaluate the housing and seal materials together.

Material Selection Tool

Search for your chemical

You can compare up to three chemicals side by side. The ratings apply to room temperature and pure chemicals; compatibility decreases as temperature and concentration increase.

  • A Excellent — suitable for continuous use
  • B Good — available, periodic check
  • C Medium — limited; pay attention to temperature/concentration
  • D Incompatible — do not use
  • No data — not tested

Materials Guide

Which material is right for which application?

Thermoplastics

Corrosion resistance is inherent: they do not wear away like a coating to expose the underlying material. PP is an economical solution in dilute acids and bases up to approximately 100 °C, but its resistance is limited in aromatic/chlorinated solvents and oxidizing agents such as hypochlorite. PVDF offers very broad resistance up to approximately 135 °C—it is preferred for use with hypochlorite and halogens—but it cannot be used in hot concentrated caustic soda. PTFE is nearly universal in the −200…+260 °C range; however, it is mechanically soft and exhibits creep under load.

You can find this group in our thermoplastic pumps category.

Metals

316/316L stainless steel is the most common process material, but it cannot be used in hydrochloric acid and carries a risk of pitting and stress corrosion cracking in chloride environments — the assumption that “stainless steel can withstand anything” is one of the most costly misconceptions. Alloy 20 has been developed for sulfuric acid applications, and Hastelloy C for harsh oxidizing and chloride-containing environments.

You can review our Stainless and alloy pump options.

Elastomers — Gaskets, O-rings, and Diaphragms

EPDM and FKM (Viton®) behave in opposite ways: EPDM performs well in hot water and bases but poorly in oils and hydrocarbons; FKM performs well in oils and aggressive acids but poorly in hot, concentrated bases. A common mistake in the field is the habit of “using Viton everywhere”—this choice will damage the seal in a caustic line. Santoprene excels in mechanical life, while PTFE excels in chemical resistance; the two are often combined in a two-piece diaphragm.

Elastomer options are particularly in diaphragm pumps critical.

The weakest link in the chain

The parts that come into contact with the fluid are not limited to the housing: the impeller/diaphragm, O-rings and gaskets, valve balls and seating surfaces, shaft, bushings, and bearings are also exposed to the same fluid. If any one of these parts is incompatible, the entire pump is incompatible. Installing an EPDM O-ring on a PVDF-bodied pump negates the body’s resistance; the material of each component must be confirmed separately during the quotation phase.

Proper Use

What does this table show, and what doesn't it show?

Compatibility charts are a pre-screening tool: they quickly eliminate clearly unsuitable options, leaving a shortlist. They do not make the final decision on their own. Use them with an awareness of these three limitations:

  1. Temperature. The temperatures are given in degrees relative to room temperature. As a general rule, the corrosion rate roughly doubles for every 10 °C increase in temperature; a combination rated "A" at 20 °C may be rated "C" at 60 °C. Additionally, in thermoplastics , the allowable pressure decreases with temperature — make your selection based on the point where the highest temperature and highest pressure occur simultaneously.
  2. Concentration. Different concentrations of the same chemical behave differently. Sulfuric acid is a classic example: its dilute form acts as a reducing agent, while its concentrated form acts as a strong oxidizing agent, and the appropriate materials vary. Simply saying “sulfuric acid” is not enough; you must specify the percentage.
  3. Mixtures and Impurities. The tables are for pure chemicals. Actual process fluids are mixtures; even trace amounts of a chloride or oxidizing agent can degrade a material selected for use with the primary chemical.

For critical applications, the most reliable method is the immersion (coupon) test: material samples are left to stand in the actual fluid at the actual temperature, and changes in weight, dimensions, and appearance are monitored. Alternatively, written confirmation of compliance may be obtained from the manufacturer.

Limitation of Liability: The ratings provided here are compiled from general compatibility charts published by manufacturers and are for informational purposes only. It is the user’s responsibility to verify the material selection under actual application conditions; Atlas Proses makes no warranty regarding the results arising from the use of this table alone.