서지주요정보
나노여과의 이온 분리 특성에 대한 연구 및 발효 유산 정제에의 응용 = A study on the characteristics of ion separation by nanofiltration and its application to the recovery of lactic acid from fermentation broth
서명 / 저자 나노여과의 이온 분리 특성에 대한 연구 및 발효 유산 정제에의 응용 = A study on the characteristics of ion separation by nanofiltration and its application to the recovery of lactic acid from fermentation broth / 강상현.
저자명 강상현 ; Kang, Sang-Hyeon
발행사항 [대전 : 한국과학기술원, 1999].
Online Access 원문보기 원문인쇄

소장정보

등록번호

8009408

소장위치/청구기호

학술문화관(문화관) 보존서고

MCHE 99001

SMS전송

도서상태

이용가능

대출가능

반납예정일

초록정보

Ion separation characteristics of nanofiltration was investigated related to the recovery of lactic acid from fermentation broth. Ion separation characteristics of a nanofiltration membrane, NTR-729 was studied using solutions of monovalent and/or divalent ions. A method for determining membrane surface charge from the rejection of NaCl, $Na_2$SO_4$, Mg$Cl_2$ and Mg$SO_4$ solutions was proposed. It was found that NTR-729 membrane was negatively charged by this method. The rejection and the flux of a certain ion on the membrane were influenced by its concentration and the ionic strength. Rejection of divalent anions was higher than that of monovalent anions due to the repulsion between anions and negative surface charge of the membrane. Thus, cations paired with monovalent anions were more permeable to the membrane than those paired with divalent anions. It was also found that cations in a mixed-solution containing monovalent and divalent anions were more permeable than those in a solution containing only divalent anions. As the concentration of a particular ion increased, its rejection significantly decreased. It was experimentally found that the major factor for the rejection change with concentration was not the shielding of membrane by coexisting cations as reported previously but an increase in solute permeability. Similar characteristics were observed for sodium lactate. Especially, pH had a significant effect on the rejection and the flux of sodium lactate. In dilute solutions, the rejection increased and the flux decreased as the pH increased. It was due to the increased repulsion between membrane charge and lactate ions as more lactate ions existed in the solution at a higher pH. In concentrated solutions, however, the increase of pH decreased the rejection. It was considered that the effect of the change of dissociation degree with pH was dominated by the increase of permeability by high concentrations of sodium ions added to adjust pH. In the case of a fermentation broth containing 90g/L lactic acid, the rejection and the flux of sodium lactate were about 5% and 2.8L/㎡h, respectively. An irreversible thermodynamics model and a solution-diffusion model which usually used for reverse osmosis systems were applied for the estimation of the flux. However, both models could not accurately predict the flux for a broad range of ion concentrations. Incorporation of the dependency of permeability on concentration to the solution-diffusion model was found to improve its accuracy.

서지기타정보

서지기타정보
청구기호 {MCHE 99001
형태사항 ix, 81 p. : 삽도 ; 26 cm
언어 한국어
일반주기 저자명의 영문표기 : Sang-Hyeon Kang
지도교수의 한글표기 : 장용근
지도교수의 영문표기 : Yong-Keun Chang
학위논문 학위논문(석사) - 한국과학기술원 : 화학공학과,
서지주기 참고문헌 : p. 78-81
주제 나노여과
이온분리
정제
유산
Nanofiltration
Ion separation
Recovery
Lactic acid
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