Chromatography Forum

I was informed that Chromosorb P-AW is no longer being produced. I have checked with several chromatography supply companies.

Is there a good alternative support available with similar properties to Chromosorb P-AW?

Chrom P-AW is a pink mineral composed of diatom fossils. The remaining lake beds holding this mineral have been mined and only have lower levels remaining. These are contaminated with metal cations and other salts. Due to the higher costs to process this mineral into Chrom P and the perceived 'cheap' value assigned to the product it became unprofitable to produce it.

Vendors which still have this support will produce columns of high assigned value with the remaining 'cheap' product. This means that labs can only order columns from chromatography columns.

Other types of chromasorbs do not have the same physical characteristics, although Chromosorb G is the closest. Chromosorb W (aka Supelcoport) is more inert but has a much lower phase capacity than the P.

The diatomaceous earth used to absorb spills is not really a substitute for the P.

If you would relate the application you seek to accomplish with the P I might be able to offer you advice.

best wishes,

Rod

Thanks for the information.

If we could only get a graduate student with time on his hands, who might receive a ton of sample to process, and a company sponsor to finance the project, we might have enough Chromosorb P to last us for a decade and a paper to write for the library.

There are many applications in the petrochemical industries that will require a re-engineering of analyzers without this product.

Any takers out there?

Rod

How about the diatomaceous earth product sold as a drying agent for the ASE type extractors? Similar purity issues? I recall this stuff always seemed to cost too much as well, though.

I think I used this stuff for a filter aid as well.

I would think so. The acid and purifying and deactivation treatments used for preparing Chromosorbs supports are quite thorough and are expensive.

best wishes,

Rod

In regards to an application for finding a replacement for the P and the Petrochemical industry, I beleive it would be C4 applications - from NC4- through C-2-Butene. Any suggestions?

Perhaps you can try RESTEK. I just recently bought column CHR-PAW from them. Hope it helps

Regards,
Alice

Yes, Alice, the vendors who make columns have a limited supply of the Chromosorb P AW to make columns, but the question is about availability of the uncoated support. It is not being manufactured and when the vendors run out, it is gone.

And no vendor I am aware of is willing to part with any of their supply of the support.

Anybody know of a good lake bed in China and a company there who would produce the support?

Rod