Introduction: Quicklime/Slaked Lime Synthesis
Here is a simple way to produce homemade quicklime and slaked lime from limestone using the process of calcining at high temperatures.
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Step 1: Production
What you need is:
containers to hold the products,
limestone (calcium carbonate),
a propane torch with some thermally resistant place to roast the limestone. I prefer a small forge.
First, take the calcium carbonate stones and put them in the forge. Turn on the propane torch to the forge and make sure the propane flame is directed on the limestone. Next, cover up the forge to keep heat in to allow the calcium carbonate to calcine better. Make sure the cover does not completely cover the front of the forge because CO2 is produced from the decomposition of the calcium carbonate that needs to easily escape. After about two to three minutes turn the propane torch off and allow the calcium oxide stones to cool for about a minute. The production of the calcium oxide is complete. Make sure the calcium oxide is stored in a tightly sealed container because calcium oxide will absorb CO2 from the air producing calcium carbonate all over again.
If calcium hydroxide is preferred, simply drop the calcium oxide stones into water. The calcium oxide stones should sputter and disintegrate into a fine powder. If the stone does not disintegrate then the stone needs to be calcined to turn its calcium carbonate content into calcium oxide. Now you have lime water which you can dry to get powdered calcium hydroxide. The presence of calcium hydroxide can be confirmed by bubbling CO2 into settled calcium hydroxide (lime) water causing a finely powdered fog of insoluble calcium carbonate to precipitate out of the lime water.
I hope you enjoyed and learned something! :)