The leaching method for oil production is based on the principle of extraction. An organic solvent that can dissolve grease is selected (normally hexane or 6# solvent).

The solvent extraction method for oil production is based on the principle of extraction, using an organic solvent(usually hexane or No. 6 solvent) that can dissolve oil. After the solvent contacts with the oil through soaking or spraying, the oil in the cake can be extracted.