Extraction of nicotine from tobacco

The present invention relates to a method of extracting nicotine from tobacco. Tobacco contains 1-5% of nicotine, tobacco farmers harvest each year, the fine can be directly sold to the state, the low-order tobacco and tobacco stems are often thrown away, wasted, the present invention is that the first tobacco, tobacco stems immersion, squeezing to obtain leaching solution, and then extracted with an organic solvent, and finally backwashing with an acid to give a nicotine salt.