Organisms are built mainly of carbon, hydrogen and oxygen, but they use many more chemical elements, one of them is potassium. After burning of organic matter, potassium stays in ashes as oxide that later is transformed to hydroxide. In the environment, potassium exists in a mixture of three isotopes: 93.3% of 39 K, 6,7% of 41 K, and 0,012% of radioisotope 40 K. The amount of mentioned 40 K radioisotope is really tinny, but sufficient to be detected using home methods.
In this post I will present a simple method to extract potassium compounds from ashes. Purity of the end product is low, from what I found online, for wood ashes, it's around 20-30%.
What is needed? Cigarette ash (for this experiment I used remains of 192 cigarettes - I'm a smoker!), water (can be tap water), stove, pot, two beakers (or jars), funnel, cotton, stirrer (or spoon). The whole process takes a couple of hours.
I've started from removing cigarette buts, matches, and other junks, the result was ~130ml of ashes.
Next I added water to 500ml and heated the mixture in provisional heated bath.
Next I separated water solution from insoluble residues. I placed a small piece of cotton into the funnel and let the solution flow though it.
To remove water, the solution has been boiled in a heated bath during a couple of hours. Later it was placed in a Petri dish. Remaining ashes were also heated to remove remaining water.
Please note that obtained mixture is skin irritating, don't touch it with bare hands!
As visible below the PH of obtained product is highly alkaline, around pH12.