Title : Volumetric and Spectroscopic Studies of Binary Mixtures of Ionic Liquid and Alcohols for Application in Enzyme Catalysis
Name of the Student: Md. Ahad Ali
Name of the Supervisors: Md. Abu Bin Hasan Susan
Abstract:
In this study, three binary mixtures are prepared by mixing an ionic liquid, 1-ethyl-3-methylimidazolium ethylsulfate ([EMIM][ES]) with a monohydric alcohol propane-1-ol, a dihydric alcohol propane-1,2-diol and a trihydric alcohol propane-1,2,3-triol. Volumetric properties of all the three binary systems along with their pure components are studied by measurement of density, viscosity and refractive index. The excess molar volume, dynamic viscosity deviation, excess molar Gibs free energy of activation for viscous flow are calculated and fitted with Redlih-Kister type polynomial equation. The results are correlated with molecular level interactions. The thermodynamic activation parameters are also calculated from Eyring equation and variation of them with [EMIM][ES] infers the change in molecular level interactions. The near infrared (NIR) spectroscopic measurements were done at temperature from 293.15 K to 333.15 K. The raw NIR data were analyzed further by two-dimensional correlation spectroscopy and principal component analysis. From the NIR spectroscopic analysis with combination of volumetric properties the molecular level interactions are found. The kinetics lipase catalyzed hydrolysis of para-nitrophenylbutyrate in the binary system are studied. Although rate of lipase catalyzed reaction decreases with increasing mole fraction of propane-1-ol, it gave a prospect to control the rate of reaction by varying the amount of propane-1-ol in the binary system. Also, the novel characteristic molecular level interactions and improved thermodynamic properties made the binary mixture a pantheon of several potential applications.
