"Bert" wrote in message
...
"Harold & Susan Vordos" wrote:

I'm no chemist, but my work with precious metals got me somewhat
acquainted
with acids. One of the things you get when you buy the higher
concentrations isn't just that, you also pay for the level of purity.

Not true. Purity and concentration are independent variables. Both lab
grades and technical grades are available in a variety of
concentrations. Lab grades cost more than technical grades; higher
concentrations cost more than lower concentrations; and smaller
quantities cost more (on a $/volume basis) than larger quantities,
sometimes much more.

For example, VWR offers 0.5 L of reagent grade HNO3 for $49.35 (70%)
and $184.55 (90%). The 70% is also offered in a 2.5 L container for
$67.65, which is less than $20 more than the cost of the 0.5 L
container, or nearly a 73% discount! Go figure. VWR doesn't list any
technical grade HNO3.

Finding a source for small quantities of technical grade HNO3,
especially in the higher concentrations, can be problematic. If you
know of a good source, please share!

Bert

Sorry to say my information reflects my experiences of days long gone. I
sold my refining business in '94, in no small part because of the terrible
increases in the price of acids and more restrictions placed on me because
of my location, which was not exactly suited to the activities at hand.
However, I was buying tech grade HNO3 from Great Western Chemical for just
over $200 per drum, which I owned, a lucky purchase from the UofU surplus
store. As you know, the drums are stainless and have a tremendously
expensive deposit ($400 at that time) if you don't happen to own your own.
I went through a drum (50 gallons as I recall) about twice a year.

The only purchases of reagent grade nitric I made were in 5 pint bottle case
lots, and they were higher in concentration, and correspondingly higher in
price, too. It was for that reason I assumed that quality went hand in
hand with concentration, but I realize that there could be a need for high
purity at lower concentrations, so what you had to say makes sense. I
used reagent grade for my testing solutions, so my demand was relatively
small.

You think HNO3 is expensive? Try pricing bromine! I used that as an
oxidizer for gold recovery from complex ores using cyanide. Killer
expensive in small quantities, yet completely affordable if bought in
volume. At least it was that way back then (about 1980).

Oh, yeah. While I could have stayed in business, I chose to retire early.
Operating costs didn't really drive me away. Love being retired!

Harold