You will need
- Soda ash, hydrated lime, boiler
Stock up on the starting substances for the preparation of alkali – sodium hydroxide. 1 kg of soda ash take 0.9 kg of slaked lime. Prepare the soda solution, to which 1 kg of soda dissolve in 4.5 l of water.
Place the soda solution into the boiler (you can just dissolve the baking soda in the cooking pot). Heat the liquid up to 60C.
The boiler in the small portions pour in water mixed with slaked lime ("lime milk"). As the solution foams and can go over the edge, load the boiler by two thirds of its volume. During cooking, stir the liquid well; the more carefully you stir the liquid, the better will be the process of turning ordinary soda to caustic soda.
Heat the resulting mixture for one hour, then allow it to settle. Pour the clear solution from the sediment. This transparent liquid is a solution of caustic soda or sodium hydroxide, the most common alkali (chemical formula NaOH). The precipitate is not soluble lime, chalk and some impurities.
After removal of the clear solution to the remaining sediment add water and boil several times and then let it stand. Then again pour the clear liquid, representing the solution of sodium hydroxide, but less degrees.
If the saponification of the fat with the aim of making soap needs a stronger alkali, the resulting solution should be evaporated. After evaporation of water, the alkali solution becomes more robust. Accordingly, if for your needs the essential alkali of less degrees, dilute the solution with water. When the described method make caustic soda 1 kg of soda ash would be about 0.8 kg of the final product.
Advice 2: What is lye
Lye is the alkaline hydroxides, alkaline earth metal and ammonium. These include well soluble in water grounds. The anions OH− and the metal cation formed by the dissociation of alkali.
In the periodic table the alkali include hydroxides of metals of subgroups Ia and IIA (beginning with calcium), e.g., Ba(OH)2 (caustic barytes), KOH (potassium hydroxide), NaOH (sodium hydroxide), which bears the popular name "caustic alkali". Caustic alkalis are sodium hydroxide NaOH, lithium, LiOH, RbOH rubidium, potassium hydroxide and cesium CsOH. They are white, solid and very hygroscopic substances.Alkalis are strong bases that are readily soluble in water with considerable heat release during the reaction. Water solubility and strength of the base increases with increasing radius of the cation in each group of the periodic system. The strong bases are the hydroxide caesium in group Ia hydroxide, and radium in group IIa. The aqueous solution of the gas ammonia, called ammonia is a weak alkali. Slaked lime is also a sodium alkali. In addition, caustic alkali can be dissolved in methanol and ethanol.All alkali in the solid state absorb water and carbon dioxide from the air (in the solution), gradually turning into carbonates. When an important chemical property – the ability of the formation of salts in reaction with acids, alkalis widely used in industry. Unable to conduct electricity, therefore they are also called electrolytes.It is possible to obtain alkali by the action of water on oxides of alkali metals or by electrolysis of chlorides.Properties of alkalis dissolve the fat, some of them can dissolve animal and vegetable fabric, destroying clothing and irritate the skin, can interact with some metals (aluminium) protect the steel against corrosion.Alkali and acid are dangerous, they should only be kept in special containers, labeled, and in any case, not drinking vessels. When working should wear safety glasses.