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How do you ake potassium nitrate from fertilizer? Answered

I have some fertilizer and i need to make potassium nitrate from it.


Get stump remover, then dissolve it in water. Pour the solution through a filter, through a funnel, then into a steel/pyrex container you don't want anymore. Boil the water off and wait for the crystals to start forming. Drive off the remaining moisture by placing the container with the crystals and a little bit of solution in a warm, dry place until the water is completely gone. What you are left with should be 98%+ purity KNO3.

NOTE: The stump remover must be mainly KNO3 for this to work.

Most common fertilizers are mixtures of ingredients; ammonium sulfate, potassium chloride, phosphates, trace elements... If the fertilizer did not contain potassium nitrate, then you are probably not going to be able to obtain potassium nitrate from it.

you can get pure potassium nitrate for growing tomatoes

I thought fertilizer was mainly composed of ammonium compounds. You're probably better off to just go out and by some, it's often sold at drug stores.

Historically, nitre-beds were prepared by mixing manure with either mortar or wood ashes, common earth and organic materials such as straw to give porosity to a compost pile typically 1.5 metres high by 2 metres wide by 5 metres long.] The heap was usually under a cover from the rain, kept moist with urine, turned often to accelerate the decomposition and leached with water after approximately one year. The liquid containing various nitrates was then converted with wood ashes to potassium nitrates, crystallized and refined for use in gunpowder. Urine has also been used in the manufacture of saltpetre for gunpowder. In this process, stale urine placed in a container of straw hay is allowed to sour for many months, after which water is used to wash the resulting chemical salts from the straw. The process is completed by filtering the liquid through wood ashes and air-drying in the sun. Saltpetre crystals can then be collected and added to brimstone and charcoal to create black powder. Potassium nitrate could also be harvested from accumulations of bat guano in caves. This was the traditional method used in Laos for the manufacture of gunpowder for Bang Fai rockets.