Basically, most alkaloids come in two forms--freebase, or salt. Freebases tend to have much lower vaporization points, and thus are prefered for smoking or vaporizing. But because most alkaloids are unstable and corrosive in their standalone basic form, they are usually stored in their salt form--which is much more water-soluble and thus prefered for injecting or snorting. The process of converting a drug into its freebase (and administering it by vaporization is called freebasing).
The first part of this process is usually done by simply dissolving the salt in a polar solvent such as water to dissociate the protonated alkaloid from the conjugate base of its acid. To remove the extra proton from the alkaloid, a base, typically ammonia, is added yielding the freebase alkaloid. To recover the freebase, ether is added to the solution since freebase cocaine is very insoluble in water but highly soluble in nonpolar solvents. After removing the ether layer from the water, the ether is evaporated off, and one will be left with the pure freebase which will most-likely be an oil and can be vaporized and inhaled.
Vaporization is often done out of oil pipes, lightbulbs, or test tubes. Another common way of freebasing, though less efficient, is chasing the dragon.
Cocaine, Crack Cocaine, and Freebase Cocaine
There is a lot of confusion around the terminology for various forms of cocaine. What is commonly referred to as Cocaine is usually Cocaine HCl which is the salt form of Cocaine.
Cocaine can be freebased by neutralizing the HCl molecule attatched to it by either mixing a Cocaine HCl solution with NH3(ammonia) or baking soda(baking soda). Ammonia is usually used to produce pure Freebase Cocaine. Water-insoluble adulterants can be filtered out before adding the base, and other water-soluble impurities are removed when the Cocaine freebase is removed with ether. However, this process often requires volatile solvents such as diethyl ether or ethanol as mentioned above.
Later, it was found that by neutralizing the Cocaine HCl solution with Baking Soda and evaporating it without removing the salt byproduct produces Crack Cocaine. Although Crack Cocaine is technically an impure form of Freebase Cocaine, it is easy to make and only requires Cocaine powder(Cocaine HCl), Baking Soda, and water.
It should be noted that freebasing is a great way of increasing your chances of ODing
on a drug
, and Cocaine HCl/Freebase Cocaine/Crack Cocaine are all very harmful for your body.