2-(Dibutylamino)ethanol as a switchable solvent for lipid extraction from microalgae

The switch performance of 2-(dibutylamino)ethanol(DBAE)was tested in the paper,and the product after switching was analyzed by FT-IR.The method of solvent recovery was also studied.Lipids from wet algae Desmodesmus sp.was extracted and recovered using DBAE as extracting agent and CO2 as a trigger.The effect of time,temperature and solvent to feed ratio on lipid extraction yield were investigated,and the compositions of extracted lipids were analyzed by GC-MS.Research results show that DBAE can switch between hydrophobic form and hydrophilic form by the injection and removal of CO2.The DBAE recovery efficiency is87.5% under 80℃ with N2 addition.When heptane is used for solvent recovery in a ratio of 10∶1(water∶heptane),the recovery efficiency can reach 98.3%.The extraction yield at 80 ℃is 5.64% which is 5to 6times higher than that at 25 ℃.GC-MS analysis shows that the oleic acid content(38.77%)is the highest among the total fatty acid,followed by palmitic acid(20.92%)and linoleic acid(20.62%).