著者

藤岡 留美子 吉田 雅子 吉村 知珠 山村 知子 真鍋 征一

出版者

福岡女子大学

雑誌

福岡女子大学人間環境学部紀要 (ISSN:13414909)

巻号頁・発行日

vol.29, pp.29-36, 1998-02-25

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We intended to validate the possibility of the development of the novel membrane separator based on the difference in the diffusion coefficient D of the particles in water as a medium and the difference in the intermolecular interaction between the raw material of the membrane and the particles dispersed in the solution. In order to confirm a dominant position of the use of the diffusion in a pore of the membrane we investigated about the following four points : (1) The separation of the dyes with different D values and with the similar molecular weight to each other, and the separation of the particles with the different size through the diffusion in a pore. (2) The separation in the combination with the diffusion and the filtration. (3) The separation of the components having different size and affinity with each other. (4) The novel membrane separator based on the combination of three separation mechanisms of the diffusion, filtration, and adsorption and its separation characteristics. The virus removal filters named as PLANOVA^<TM> which was composed of the cuprammonium regenerated cellulose hollow fibers were employed. The mean pore sizes of the filter were 15,35 and 75nm and PLANOVA 35 with 35nm in mean pore size was investigated rigorously for the separation properties. The diffusional particles dispersed in water were the acid dye (Orange II (C.I. 15510)), the direct dyes (Congo Red (C.I. 22120), Direct Blue 6 (C.I. 22610)), the basic dyes (C.I. Basic Blue 7 (C.I. 52595), C.I. Basic Brown 1 (C.I. 21000)), oval albumin, three gold particles with 15,36 and 42nm in mean particle size. The D value under the stationary state was determined through the hollow fiber method. The filtration was carried out under the constant transmembrane pressure ΔP and the dead end filtration. The filtration rate J and the membrane permeability φ were evaluated. The partition coefficient K was measured through the change in the particle concentration in the immersing liquid of the sample. The particle concentration was determined through the optical absorbance measured using the UV-visible spectrometry. We obtained the following results : (1) The components with different D values in water (as one of media) could be separated through the diffusion in pores under the stationary condition using a porous membrane. The D values of the components in a mixed solution changed so as to get close to each others. The separation ratio was given by the ratio among the D values of the each component. (2) As for a filtration, the separation related to the difference of the D value was observed slightly. The separation ratio decreased with an increase in ΔP. When the size of the component particles was different largely, then the separation based on the filtration worked effectively. The filtration rate decreased with time. (3) The particles having larger size than the mean pore size could be removed by the diffusion without the decrease in D value with diffusion time for the smaller particles. However, the coexistence gave rise to decrease the absolute value of D for smaller particles. (4) The separation of a few components could be separated concurrently by the novel membrane separator composed of two filters through three mechanisms of separation based on the differences of the affinity, the particle size, and the diffusion coeficient. By the use of the diffusion in a pore of a porous membrane, we can separate the components in the following two cases, the case that the diffusion coefficient in a water for the components are different with each other, and the case that the affinity of the components to the raw material of the porous membrane is different with each even if the particle size is not so different. In the former case, the transportation speed is about 10^3-10^4 times to that of the diffusion in a non-porous membrane. The development of a novel membrane separator which makes use of the difference in the diffusion, the filtration and t