Where the
world gathers for metal finishing
Q&As since 1989


-----

Sulfuric acid in PE tank

Dear sir

I am an environmental engineer in a PCB manufacturing company.

We store 50% sulfuric acid in PE tank presently.
1. Can we store sulfuric acid in PE material?
2. Can we store 80% or 98% sulfuric acid in PE tank?

Thanks and best regards!

Li Long Chang
- Wuxi, Jiangsu, China
2003

---

2003

Hi Lee Long !

Re 80% sulfuric ... borderline ... probably OK
Re 98% sulfuric ... failure

Even for 80% sulfuric, I'd recommend very strongly that you DON'T weld on any outlets ... just use tank adaptors (sometimes called bulkhead adaptors) made from PVC but with a suitable, probably Viton, gasket rather than epdm.

Next, I'd only use moulded Pe tanks. On top of that I'd get the moulder to increase the wall thickness to 1/2" for two reasons, 1) better long term resistance 2) stiffer construction due to the 'heavier s.g.' 80% concentration. This applies to the so-called Engel rotational moulding process.

Re 93% (which is the commercial grade for battery plants in Canada) ... I've used regular PVC for YEARS AND YEARS ... and there is one PVC that is said to be OK to 98%.

Have a glance in the archives at # 8698 and # 18489 for some pointers.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

Freeman is right about the welded bit. That is so bad that I did not even consider it as a possibility. Now, PE covers a terribly wide range of product. Low linear density PE can not really be compared to High level and certainly not to Ultra high. And that does not even touch linking mechanisms that I do not even try to understand. You need to specify what you mean when you use generic terms like PE. It does make a very large difference.

James Watts
- Navarre, Florida
2003