Force Field Development and Monte Carlo Simulation of Associating Fluid containing Non-ionic Surfactants ; 비이온성 계면활성제를 포함하는 회합성 유체에 관한 역장 개발과 몬테카를로 시뮬레이션

Alkoxyethanol has both hydroxyl (-OH) and ether group (-O-), so inter- and intramolecular hydrogen bonding can occur which can be a main reason for the nonideal phase behavior of alkoxyethanol system. In this work, the associating fluid was studied experimentally and theoretically focusing on the phase behavior of the fluid system containing alkoxyethanol. Firstly, isothermal or isobaric vapor-liquid equilibria of alkoxyethanol + hydrocarbon mixtures were measured. The measured data were correlated using equations of state and activity models. Following that, to understand the association of alkoxyethanol and its mixture from molecular level, Monte Carlo (MC) simulation was performed. For that, newly optimized potential model was developed, named as Optimized Potential for Phase Equilibria Simulation (OPPES) providing the potential parameters of intra and intermolecular interaction of n-alkane, linear ether, primary alcohol, glycol and alkoxyethanol. Using OPPES model, a number of Gibbs ensemble Monte Carlo simulations (23 NVT and 3 NPT simulations) were carried out for aforementioned chemical species. The simulation results were compared to the experimental data to show the performance of OPPES model. Especially, the comparison elucidated the hydrogen bonding plays a significant role in understanding the associating fluids and their mixtures containing alkoxyethanol. The results of this study can be directly used for a variety of theoretical study. In particular, OPPES model is expected to improve the oversimplified intramolecular hydrogen bonding term of the lattice fluid EOS using Veytsman statistics. ; 분자간, 분자내 회합은 이를 형성하는 화합물의 상거동에 매우 큰 영향을 미치며 이에 대한 실험적, 이론적 연구는 회합성 유체에 관한 학술적, 이론적 연구에 있어서 가장 기본이 된다. 특히 알콕시에탄올은 한 분자 안에 히드록실기와 (-OH) 에테르기를 (-O-) 함께 지니고 있어 분자간, 분자내 회합이 동시에 이루어질 수 있으므로 이에 대한 연구의 중요성은 매우 크다고 할 수 있다. 본 연구에서는 알콕시에탄올과 그의 혼합물을 중심으로 회합성 유체에 관한 실험적 그리고 이론적 연구가 이루어졌다. 첫째로, 알콕시에탄올과 탄화수소 혼합물의 기액 상평형이 측정되었다. 측정된 데이터는 비리얼 상태방정식, 활동도 모델 (NRTL, Wilson, Uniquac and three suffix Margules) 그리고 MiALF ...