本論文以超過濾膜PAN-100 kDa及PES-100 kDa來進行雙成份蛋白質分離,本實驗所使用的蛋白質為牛血清蛋白(BSA)及牛血紅素(HB),配合Dead-end及Cross-flow過濾膜組來進行實驗。本研究共分為Design-expert實驗設計單成份過濾實驗、Dead-end 雙成份超過濾實驗、Cross-flow雙成份超過濾實驗及添加吸附劑增加單一蛋白質吸附率實驗,最後再以Blocking filtration law來分析阻塞機制。 在Design-expert實驗設計方面,初步得知緩衝溶液pH值低於蛋白質pI點時,容易造成單一蛋白質的截留率大增及清水透過率減低等情況。Dead-end超過濾方面,低壓高pH值時,分離比以pH 7.10時為最佳。添加鹽類0.01 M時,通量降落低,分離效果佳。在Cross-flow超過濾方面,通量降落較Dead-end低20 %左右,極限通量出現在10 ~ 20 psi間,分離比以pH 7.50及7.10時較佳。在阻塞分析方面,濃度比5 : 1 (BSA : HB)當pH ³ 7.10時,過濾初期以孔洞內部阻塞為主,隨著時間拉長,漸以濾餅過濾為主。當pH < 7.10時,阻塞為一複雜情況。在添加吸附劑方面,蒙托土可在pH 7.10時將HB吸附增加雙成份蛋白質分離效率。IRC-76在pH 6.0時對HB有良好吸附效果。
This work used PAN and PES ultrafiltration membranes both MWCO, 100 kDa to separate proteins from binary solutions. Two reagents, bovine serum albumin (BSA) and brovine haemoglobin (HB) were separated via the ultrafiltration process. The study was divided into two parts. First, we used the Design-expert experiment software for analyzing single protein (BSA) filtration data, then we used dead-end and cross-flow modules to separate binary proteins and added adsorbent to improve the separation ability via selective adsorption. Finally, we used blocking filtration law to analyze fouling mechanism. The design-expert experiment analysis show an increase in the single protein rejection and flux decline at pH < pI. Experiments of dead-end ultrafiltration showed that there is high separation factor at 10 psi and pH 7.10. It was shown that salt will results in a low flux decline and high separation factor. Cross-flow ultrafiltration experiments revealed a 20% less flux decline than the dead-end module, and the critical flux appeared at a pressure of 10 to 20 psi. The separation factor at pH 7.50 and 7.10 was the best. In the case of, the concentration ratio being 5 : 1 ( BSA : HB ) and pH ³ 7.10, the initial filtration mechanism is caused by internal blocking and later is responsible for cake fouling. When pH < 7.10, the blocking mechanism was complex and a model was used to find out the fouling time and fouling flux. The use of montmorillonite to selevtivly adsorb HB can increase the separation factor of HB and BSA.