Solubility of organic compounds in dense gases and mathematical modeling

Cilj diplomske naloge je bil določiti topnost organske spojine (metil acetata) v plinih visoke gostote (tj. superkritičnih fluidih: CO2, N2, Ar) s pomočjo statično-analitične metode ter matematično modelirati podatke s pomočjo programa Microsoft Office Excel. Namen modeliranja je bil korelirati že obstoječe podatke in napovedati obnašanje sistema v regijah, kjer eksperimentalni rezultati niso dosegljivi. Vse meritve smo izvajali v visokotlačnem avtoklavu. Rezultati prikazujejo kako lahko majhne spremembe temperature in/ali tlaka povzročijo velike spremembe gostote topila (CO2, N2, Ar) in s tem različne vzajemne topnosti v sistemu snov/superkritični fluid. Eksperimente smo izvajali pri treh različnih temperaturnih pogojih (40 °C, 60 °C in 80 °C) v območju relativno nizkih tlakov (10-170 bar). Ugotovili smo, da se s povečanjem tlaka masni delež zmanjšuje, gostota pa se zmanjšuje s temperaturo in povečuje tlakom.The aim of the thesis was to determine the solubility of organic compounds (methyl acetate) in dense gases (i.e.: supercritical fluids: CO2, N2, Ar) by static-analytic method and mathematical data modelling by using Microsoft Office Excel. The goal of modeling was to correlate the existing data and to predict the system behaviour in regions where experimental results are not available. For all measurements, a high-pressure autoclave was used. The present thesis reviews how small temperature and/or pressure changes result in large changes of solvent density (CO2, N2, Ar) and thus cause a various mutual solubilities in the substance/supercritical fluid system. Experiments were carried out at three different temperature conditions (40 °C, 60 °C in 80 °C) in the range of relatively low pressure conditions (10-170 bar). We have found out that by increasing the pressure mass fraction starts to decrease. Furthermore, density decreases with temperature and increases with pressure