How is nicotine extracted from tobacco leaves and solubilized?

1 Answer
Apr 9, 2018

Here's what I get.

Explanation:

Nicotine is a colourless, oily liquid with a boiling point of 247 °C.

Its structure is

thesciencesofsmoking.files.wordpress.com

It is a base and exists in the plant as the salt of various acids.

We can represent the reaction as

#"Nic + HA" → "NicH"^"+" + "A"^"-"#

Here is a simplified version of the industrial process for extracting nicotine.

1. Cut the leaves to pass a 6 mm sieve.

2. Add a lime slurry to free the nicotine from its salts.

The reaction is

#"NicH"^"+" + "OH"^"-" → "Nic" + "H"_2"O"#

3. Heat the slurry with superheated, pressurized steam.

The process is effectively a steam distillation of the oil.

4. Condense the vapours.

5. Extract the nicotine from the condensate with kerosene.

6. Extract the nicotine from the kerosene with 25 % sulfuric acid.

#"2Nic(kerosene)" + "H"_2"SO"_4"(aq)" → ("NicH")_2"SO"_4"(aq")#

7. Use alkali to adjust the solution to pH 6 for safe transport in metal containers.