You can test for chlorides with a little silver nitrate solution. Any
chlorides (or other halides) will ppt out. Make sure you use distilled
water to make up the testing KN03 solution.
Insouble material is easy enough, just make a solution. Gross contamination
will be obvious, filter with some nice clean white and high quality filter
paper, examine for residue.
Calcium species can be ppt'ed out with sulfates or hydroxides. Large sodium
content would show up on a flame test. AFAIK that's about the limit of what
you can do with simple equipment and easy to get (say photographic)
chemicals, I am not much of a chemist though, others here might have better
If its quality proves poor you can clean it up fairly easily with
filtration, potassium hydroxide, and a few cycles of recrystalisation. It
is a pain to do, but it has to beat just throwing away 25 kg of raw materials.
Post by aborza
A friend gave me a fifty pound bag of bag of Haifa Chemicals Greenhouse
Grade Multi K potassium nitrate soluble fertilizer.
The only thing on the bag that identifies the purity of its contents is the
N-P-K ratio of 13.5-0-46.2.
I have Googled the web and news groups for data on this product with little
success. The company's web site does not provide MSDS information and simply
says that the product contains less than 1,000 parts per million insoluble
contaminants and that there are no chlorides in the product.
Additional detailed information can be found here;
Can someone point me to an MSDS for this product or suggest a method of
determining its purity from the data provided on the web site referenced
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