How do you extract potassium nitrate from fertilizer?

I have been fiddling around with a few homemade fireworks, and I have found a certain want for potassium nitrate, something which works very well in fireworks. Does anyone know how to remove this from my everyday garden fertilizer? I heard it can be done, I just dont know how... Thanks! P.S. I dont need any warnings about using fireworks, I am very sensible.

52 answers
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Feb 2, 2009. 12:56 PMbylerfamily says:
How many percent potassium nitrate is your fertilizer?That would help.
Feb 2, 2009. 3:58 PMbylerfamily says:
Well, you can boil the water with fertilizer until you get a white crust on the bottom.Another way is to dissolve the fertilizer in water.Then stick a cotton string through the water and leave it over night.It will grow crystals on the cotton string.
Feb 3, 2009. 4:46 AMbylerfamily says:
You're welcome.I like to help people when I can.
Feb 6, 2009. 9:07 AMbylerfamily says:
Did it work?
Feb 6, 2009. 11:56 AMbylerfamily says:
Maybe you could heat the water so you could dissolve more fertilizer.Then try to use only 2 strings so you get more per string.Then it is easier to collect it.Sorry you did not get very much. p.s.What percent fertilizer did you use?(10 or 30)
Feb 6, 2009. 5:17 PMbylerfamily says:
What fireworks are you making?I am interested in fireworks to.
Feb 7, 2009. 4:16 AMbylerfamily says:
I saw the instructable too.
Feb 7, 2009. 7:09 AMbylerfamily says:
Yeah.
May 19, 2013. 5:32 AMgio52 says:
Multi-KTM, Haifa’s potassium nitrate brand, is the base of a whole line of plain and enriched potassium nitrate fertilizers, designed for optimal plant nutrition.
Multi-KTM is fully water soluble, and consists of 100% plant macronutrients. The Multi-KTM potassium nitrate fertilizers are efficiently absorbed by plants, and the presence of nitrate enables the plant to minimize its uptake of chloride, whenever this deleterious anion is present in the soil solution or in the irrigation water. This makes Multi-KTM a necessity for chloride-sensitive crops
You can visit the site: http://www.haifa-group.com/products/plant_nutrition/multi_k_potassium_nitrate_fertilizer/
Jun 19, 2012. 7:58 PMfzbw9br says:
KNo3 is a controlled substance in Canada

if you use it for ANYTHING that goes BANG, you are in violation of Federal Explosives laws

you can find all the info online

look up firearms act and explosives act, I think those two will tell you all you need to know
May 30, 2011. 7:59 AMjwhite6 says:
you might want to careful about what you say on the Internet........ you have just ask how to get potassium nitrate from fertilizer. you could use the first couple of suggestions to get ammonium nitrate ( a highly explosive substance) from fertilizer. Bearing in mind that the I.R.A used fertilizer to make bombs (as well as other substances).

im NOT saying you ARE a member of the infamous I.R.A but it do sound a bit dodgey. even if it is for fireworks.
Mar 28, 2009. 9:37 PMJohn Smith says:
1. buy garden fertilizer 2. throw away garden fertilizer 3. buy spectracide stump remover 4. use stump remover for KNO3
Sep 24, 2009. 2:53 AMbackyardmunitionist says:
Heh laffed my balls off when I read this. ( I think I need to get some sleep)
Feb 27, 2009. 1:48 PMShadowfury says:
First, most fertilizers use Calcium Nitrate, not Potassium Nitrate. Second, use stump remover. Most brands have a really high ratio of Potassium Nitrate to additives. All you have to do is dissolve it in water, boil it down until it crystallizes, then crush the crystals. Alternatively, you could dissolve it in water, then run it through a filter. The filter should remove any contaminates, at which point you should boil it down. Really it depends on how pure you want it. I recommend the latter, as it produces better results. Remember, the additives (collectively referred to as "contaminates") can produce adverse behavior in pyrotechnic mixtures.
Jul 15, 2009. 4:04 PMbylerfamily says:
You can?That is great.Had success with your fireworks?
May 16, 2009. 7:42 AMadrigal1234 says:
Go to a garden centre and buy a box of sulphate of potash and a box of nitrate of soda make a saturated solution of both chemicals mix them and bring the liquid to a gentle boil for 4 minutes allow to cool and separate the white precipitate from the liquid and discard the precipitate. heat the to reduce it and Kno3 crystals will form at the bottom.
May 3, 2009. 5:54 PMjashaszun says:
I_am_Canadian, i found a fertilizer thats 99 percent potassium nitrate! I think its called Grant's Stump Remover, and whoever said that stump removers have a lot of PN (potassium nitrate) you r rite! bye
Apr 12, 2009. 2:42 AMT.K says:
can u make potassium nitrate with any fertilizer
Feb 4, 2009. 10:04 PMBartboy says:
You are Canadian! "P.S. I dont need any warnings about using fireworks, I am very sensible." In Canada, homemade fireworks are ilegal. In fact, fireworks themselves are only legal in the 3 weeks surrounding hallowee!
Feb 20, 2009. 5:07 PMCountry dude says:
is it called victoria fireworks because ilive near there
Feb 22, 2009. 4:32 AMCountry dude says:
O ok but nice talking to you
Feb 5, 2009. 3:33 PMBartboy says:
Do they have a visible license? Do they sell to minors? This law may not apply in Manitoba.
Feb 6, 2009. 8:03 PMBartboy says:
Odd, Good. Why?
Feb 2, 2009. 4:04 PMknexfan9182 says:
we all know its not for fireworks you're going to blow up your hands.
Feb 3, 2009. 5:43 PMOwenmon says:
shoot then out of your cannon! :D
Feb 2, 2009. 6:23 PMknexfan9182 says:
then America
Feb 2, 2009. 8:19 PMknexfan9182 says:
sigh potassium nitrate is commonly used as blasting agent in mines and can be use too make an i.e.d..
Jan 4, 2012. 8:19 AMbadassintheshadows says:
um...
<---american
Feb 3, 2009. 10:05 AMknexfan9182 says:
No I'm just messin around with you.
Feb 3, 2009. 2:54 PMknexfan9182 says:
just in case some nsa guys go over to your house I don't have anything that can help you because I don't know what laws are over in Canada.
Feb 2, 2009. 5:21 PMmynameisjonas says:
yeah, I don't know how to extract it from fertilizer. but you can buy it fairly cheap on ebay, its like 2.50 a pound. and while your playing with KNO3, why don't you try this?
Feb 2, 2009. 2:19 PMwenpherd says:
look it up on youtube or there is a book Amateur Rocket Motor Construction it has a section on making potassium nitrate but i wudent get it unless you plan making model rocket moters cuz it cost like $30

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