The core problem
|Modern industrial production of nitrates starts with nitric acid.|
Nitric acid is produced from ammonia through the high pressure high speed platinum-catalyzed Ostwald Process.
Modern production of ammonia starts with high pressure high speed osmium catalyzed fusing of hydrogen and nitrogen: the Haber Process.
It would be easy to buy a cold pack or some fertilizer with ammonium nitrate in it, dissolve it, mix in some potash, et voilà! Saltpeter! Likewise neutralizing nitric acid with lye. But the thing is, there is essentially no natural source of ammonium nitrate or nitric acid and this is supposed to be a primitive chemistry blog.
As usual, space and time are the limiting inputs. If I had a large yard and a twelve to eighteen month timeframe, I could do all this "the right way" and not need to shortcut the system. I was pondering actually switching from renting an apartment to renting a house with a yard when something strange happened: I had an idea.
Someone else do the primitive "hard part"
There are various estimates of nitrate per ton of compost, but a consensus figure seems to hover around 1%. Thus 1kg of compost might contain 10g of nitrates.
This being southern California, there are a lot of community based composting services, because only the very rich can know that everything should be totally natural and completely free. :)
Simply buying a bag of "certified organic compost" and leaching it for nitrates would confirm whether or not the basic process worked like all the old texts say it does. So long as there were no high tech steps taken in the composting process and no external additives (neither likely in "organic" compost) it should be valid. There are even a couple of local places I could visit and see what actually went into producing the compost.
After a phone call to Agromin to make sure I was buying 100% unadulterated compost, I purchased their (rebranded) EcoScraps compost at a local hardware store.