Another common way to get the oil from plants is supercriticl CO2 extraction way.It adopts CO2 as solvent to dissolve the oil from plants. Co2 extraction machine is suitable for the dried material and Co2 has strong adsorb ability.Changing the temperature and the pressure,CO2 will be in different status.The oil is got just through the conversion of the co2 status.The product got by the CO2 extraction machine do not have the volatility.The cost of the CO2 extraction machine and the use cost are both very high,but the extraction rate is ten times higher than steam distillation.