A source of 100% o-phosphoric acid here in the US is:

Gallard-Schlesinger
584 Mineola Avenue
Carle Place Long Island NY

fax: 516 333-5628

500gram bottles #29421

I don't recall the exact cost but its between $25 and $40 per bottle.

These are acid crystals which we "clean-up" by heating in vacuo with a N2(l)
trap attached to an unhappy belt-driven pump.  We keep the acid @ just
under 100C while pumping, and check its purity via specific gravity @ STP. 
As Cap mentioned, as long as the N2(l) trap is maintained you don't have to
worry about backstreaming of oil vapors.

For those who worry about this, we haven't seen any difference in the
acid-alpha using this type of acid vs the Bowen method acid.

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This message is from:

Tom Guilderson                          [log in to unmask]
Lamont-Doherty Earth Observatory
Rte. 9-W Palisades, NY  10964

Statements made do not reflect Columbia University nor L-D EO.
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