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Leaching of thermoplastic linings by ultrapure water

I am looking for information about the performance of HDPE or PP for the long term storage of ultrapure water. This is in particular refernce to the possibilty of the leaching out of organics from the plastic and contaminating the water.

I work for a company involved in the supply of thermoplastic and thermoset resin systems. We are investigating the use of HDPE liners for protecting tanks used to store ultrapure water. The parameters are that no or negligable leaching from the HDPE takes place. Primarly I am interested in the results of any long term testing or of specific case histories.

Iain Bennett
Surface Protection - Bonn, Westerwald, Germany
2004

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2004

Hi Iain !

What you forgot to say was if these liners were pure HdPe or if they were UV protected or coloured... which, as you know, in the UV case of Pe pipe is around 5% of carbon black... but there are, as you must also know, other UV stabilizers available.

Wenn man alle Informationen zu Hande hat, kann man dann vielleicht einen guten Rat ausgeben.

Personally, if, if, if a pure unadulterated Pe is used, I'd feel that no leaching would occur.

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

The HDPE proposed will be unstabilised, natural material grade SIMONA PE-HWST. Simona themselves have no leach test information on PE but have on PP which shows some limited leaching. Their opinion is that PE-HWST will show less tendancy to leach than the PP.

Iain Bennett
- Germany
2004