膜分离法提高麦芽四糖糖浆纯度的研究OA北大核心CSTPCD

This study aimed to investigate improving the purity of maltotetraose(G4)to over 80％from its syrup by the ultrafiltration(UF)-nanofiltration(NF)membranes technology.Results showed that high recovery of total sugar and high rejection of dextrin could be obtained in permeate generated by the UF membrane XT(cut-off of 1 000 Da).The NF membrane NFX(cut-off of 150-300 Da)was most suitable for improving the purity of G4 by using permeation flux,rejection rate,and separation coefficient as evaluation indexes.The optimal nanofiltration membrane process parameters were that transmembrane pressure was 1.0 MPa,the operating temperature was 35 ℃,the total sugar concentration was 15 g/L,and the purity of G4 after nanofiltration was increased from 73.40％to 78.20％.Fur-ther,a five-stage intermittent infiltration with a concentration factor of 2 was used,and the purity of G4 in the retentate reached 87.14％.The membrane separation process could not complete the absolute separation of oligosaccharides with similar molecular weight,but the pu-rity of G4 in the product could be increased by using the different retention rates of each sugar,which would be of great significance for further study on the application value of G4.