Preparation And Properties Of Carbon Nanomaterials/polyvinylidene Fluoride Blended Hollow Fiber Ultrafiltration Membranes

In this paper,inorganic carbon nano materials were prepared by dry wet spinning,hollow fiber ultrafiltration membrane was prepared and the application of ultrafiltration technology in the purification of primary collagen was studied.Performance optimization of hollow fiber composite membrane prepared by adding 0.03wt%MWCNTs-COOH.The pure water flux up to 669.64L/(m2 h);bovine serum albumin(BSA)rejection rate is obviously increased;the tensile strength is 2.96MPa;elongation is 80.4%;flux recovery rate reached 95%.The performance optimization of hollow fiber composite membrane prepared by MWCNTs-COOH with the addition of diameter of 20nm-30nm.The pure water flux is 735.6L/(m2·h);the rejection rate of BSA is 96.9%;the tensile strength and elongation at break are significantly improved compared with the pure PVDF film,but with the increase of pipe diameter,the flux recovery rate is about 97%.Graphene oxide was added to 0.04%wt when the water flux reached 566.03L/(m2·h);tensile strength and elongation were increased by 59.48%,89.64%;XRD GO proved that the effects of polymer crystallization process,but did not change the crystal type,crystal type mainly is still a beta crystal.With the increase of the dry spinning process,the water flux of the membrane decreased,but the rejection rate of BSA was not changed.Considering the properties of the composite film and the spinning difficulty,the hollow fiber ultrafiltration membrane was prepared by selecting the length of dry spinning process as 6cm-8cm.With the gel bath temperature increased from 15 to 25?,the water flux of the membrane increased rapidly.The water flux of the membrane increased more slowly in the range of 25?-45?.All factors considered,the preparation of hollow fiber ultrafiltration membrane was better when the gel bath temperature was 25 ?-3 5 ?.The ultrafiltration technology of primary collagen solution concentration and separation and purification,the operating pressure increases to a certain extent,the membrane flux was not increased significantly,from life to consider such angle angle and film,selection pressure is 0.3MPa;separation and purification process,with the increase of flux operation time continued to decline,the permeation flux in the ultrafiltration of about 70min balance equilibrium flux is about 75L/(m2·h);through the hydraulic conductivity values with time showed a downward trend,about 920?S/cm balance;through the pH value of solution was increased with time,the balance of about 60min,about 6.5.In the process of concentration and purification,the flux increased with the increase of operation time,and the permeate flux tended to be balanced and the equilibrium flux was about 32L/(m2·h).