Abstract: The membrane technology to purify the chlorogenic acid extracts prepared from steamed fruit of Lonicera japonica Thunb. was studied in this paper. Taking the water penetration flux as index and comparing with two kinds of micro filtration membrane MF1 and MF2, two kind of ultra filtration membrane UF1 and UF2, and two kinds of nano filtration membrane NF1 and NF2, the filtration characteristics for the chlorogenic acid extraction were studied. Results indicated that the MF2 membrane flux reaches as high as 167.7 kg/h, while the UF2 membrane flux 148.8 kg/h and the NF2 membrane flux 109.8 kg/h, obviously higher than that of MF1 (103.6kg/h), UF1 (48.0kg/h) and NF1 (45.6kg/h), respectivly. Analysis results the contents of all liquids produced in the membrane separation showed that the concentration of chlorogenic acid in nano filtration concentrated solution is 17964mg/L, 24.8 times higher than that of originally extracted solution, and the purification of chlorogenic acid raises to 27% from 2.8% after multi membrane filtrations.

Key words: Lonicera japonica Thunb., chlorogenicacid, membrane technology, nanofiltration