Objective:To study the flocculation process with chitosan for Xiang A-2 Granules. Methods On the basis of the one-factor investigation such as the amount of chitosan

the concentration and pH of the extracting solution

temperature and stirring etc

the experiments for the further optimization of flocculation process conditions were arranged with orthogonal design.Results:The optimal flocculation process conditions were as follows. The adding amount of chitosan was 0.6 mL·g-1

the extract solution and medicinal materials were in the ratio of one to four 1∶4

the PH of the solution was 7

the flocculation temperature was 60 ℃

the stirring speed was 200 r·min-1 and the stirring time was 10 minutes. Conclusion:The flocculation process with chitosan can be used for the purification of Xiang A-2 Granules.