PE/PP in Concentrated Sulfuric Acid Service

[Vahid.A]

According to the NACE SP0391 standard, polyethylene (PE) and polypropylene (PP) are prone to environmental cracking in concentrated sulfuric acid. The standard highlights that:

“The likelihood of cracking increases with higher acid concentrations and temperature, and a careful review of the long-term performance of these materials should be conducted before application.”

This raises a few key questions:

How should a "careful review of long-term performance" be conducted?

Are there any cases where you would advise using PE or PP in concentrated sulfuric acid?

I'd appreciate insights from engineers who have faced material selection decisions for sulfuric acid service.

 

[EdStainless]

The real message about "long term performance" includes expected lifetime and the risks of failure.
As you can see from the above (from the MTI Materials Selector MS-1) that temperature and acid concentration are critical.
Be careful.
Most sulfuric users prohibit the use of PE in any service.