아세토니트릴-물-혼합용매계의 액-액평형에 관한 연구

다국어 초록 (Multilingual Abstract)

The extraction, separatiny operation used interactive energy and solubility of a specified components as a proper solvent add to solid or liquid materials, is known to separation skill due to the phase contact with vaporization, absorption in chemical engineering and is able to operating in various conditions and is profitable in terms of energy efficiency. Thus, the need for calculating and predicting liquid-liquid equilibria(LLE) compositions has very much increased.
The purpose of this study is to determine and describe LLE data for the ternary or quaternary systems containing acetonitrile aqueous solution and solvent at 25℃. We investigated that the selection of the optimum solvent to separate acetonitrile from aqueous solution on ternary LLE and compared with ternary and quatermary LLE including binary solvent also.
In this work, we have obtained the following result.
1. Ternary LLE
In order to systematically evalute the effect of functional group in each solvent, we selected a variety of solvents, o-xylene as aromatic compound, methyl isobutyl ketone as ketone group, ethylacetate as ester group, 1-butanol as hydroxy compound for ternary liquid-liquid extraction system.
1) The experimental binodal curves and tie-line data for solvent(1)-water(2)-acetonitrile(3) were determined and these were shown in Table 6, respectively. The thermodynamic consistency for experimental tie-line data were investigated with several correlation methods and those plots were shown in Fig. 8~9.
2) The NRTL, UNIQUAC and modified UNIQUAC models were used to correlate the experimental results and to calculate the phase composi-tions of the ternary systems. The NRTL equation fitted the experimental data better than did the other equations, and the average root mean square deviation phase composition error was 1.2003 mol % for the NRTL model, 1.3966 mol % for the UNIQUAC model and 1.8249 mol % for the modified UNIQUAC model.
3) In considering the kind of solvent, distribution and selectivity for ternary system solvent(1)-water(2)-acetonitrile(2) were increased in order of o-xylene, methyl iso butyl ketone, ethylacetate, 1-butanol Consequently, aromatic compound were more profitable than other solvent groups.
2. Quaternary LLE
We studied on the phase equilibria of quaternary liquid-liquid extraction system composed acetonitrile-water-binary solvent. 0-xylene-ethylacetate mixture, which have very often used in the actual field and this study was used as solvent of ternary system, was used as binary solvents.
1) Binodal curve, tie-line, distribution and selectivity for each quaternary system have been determined in order to investigate the effect of using binary solvent for extracting acetonitrile from aqueous solution.
2) The distribution and selectivity for quaternary system o-xylene(1)-water(2)-acetonitrile(3)-ethylacetate(4) were increased with addition of o -xylene.
3) These experimental tie-line data were also compared with the values predicted by UNIFAC model. It was shown that UNIFAC model is capable of predicting the tie-line in these quaternary systems within an average root mean square deviation of 3.98 mol %.

목차 (Table of Contents)

• 목차 = ⅰ
• Ⅰ. 서론 = 1
• Ⅱ. 이론 = 5
• 1. 액-액평형 관계식 = 5
• 가. 활동도계수와 과잉 Gibbs 에너지 = 5
• 나. 평형조성 추정 모델 = 6
• 2. 추출공정 설계와 액-액평형 = 11
• 가. 용해도곡선과 tie-line = 11
• 나. Tie-line의 건전성 = 13
• 3. 4성분계 액-액평형 = 15
• Ⅲ. 실험 = 17
• 1. 시약 = 17
• 2. 실험장치 = 19
• 3. 실험방법 = 21
• 가. 용해도의 측정 = 21
• 나. 평형조성의 측정 = 23
• Ⅳ. 결과 및 고찰 = 26
• 1. 3성분계 액-액평형 = 26
• 가. 용해도곡선과 tie-line = 26
• 나. 실험데이터의 건전성 = 28
• 다. 상계점의 결정 = 31
• 라. 모델에 의한 평형조성의 추정 = 37
• 마. 분배계수와 선택도 = 44
• 2. 4성분계 액-액평형 = 47
• 가. 용해도곡선과 tie-line = 47
• 나. UNIFAC 모델에 의한 평형조성 추정 = 51
• 다. 분배계수와 선택도 = 55
• Ⅴ. 결론 = 58
• 참고문헌 = 60
• 부록 = 64
• Abstract = 71