| Abstract | Traženi su znanstveni radovi u kojima su objavljeni eksperimentalni podatci o ravnoteži para-kapljevina u sustavu aceton (1) – voda (2). Pronađeno je 28 skupova podataka od kojih su četiri izmjerena pri izotermnim uvjetima, a ostali pri izobarnim. Pronađeni podatci testirani su integralnim i Van Nessovim testom konzistentnosti, a sedam skupova nije prošlo test konzistentnosti, svi pri višim temperaturama i tlakovima. Zatim su se određivali linearno-temperaturno ovisni parametri za modele koeficijenta aktivnosti: Wilsonov model te modele NRTL i UNIQUAC. Za određivanje parametara modela upotrijebljeni su izotermni podatci Bearea i Ramalha izmjereni pri 25 °C i 75 °C, dok je parametar neslučajnosti u modelu NRTL fiksiran na 0,3. Najmanju vrijednost funkcije cilja dao je model NRTL. Na kraju su se uspoređivali modelni dijagrami vrenja i modelni ravnotežni dijagrami s podatcima Al-Sahhafa radi provjere valjanosti modela. Uočeno je malo odstupanje – modelni dijagrami vrenja većinom daju nešto viša kapljišta i vrelišta od eksperimentalnih što je najuočljivije pri
20 000 Pa, a najmanje uočljivo pri atmosferskom tlaku. Modelni se ravnotežni dijagrami pri atmosferskom tlaku, tlaku od 80 000 Pa i 60 000 Pa dobro slažu s Al-Sahhafovim podatcima, dok pri tlaku od 40 000 Pa i 20 000 Pa postoji malo odstupanje, tj. pri udjelima acetona većim od približno 10 % modelni ravnotežni dijagrami većinom daju nešto viša kapljišta i vrelišta od eksperimentalnih. |
| Abstract (english) | Research papers with experimental data on the vapor-liquid equilibrium in the
acetone (1) – water (2) system were looked for. 25 data sets were found, four of which were measured under isothermal conditions, and the rest under isobaric conditions. The data found were tested with integral and Van Ness consistency tests, and seven sets did not pass the consistency test, all of them measured at higher temperatures and pressures. The linear temperature-dependent parameters for the Wilson, NRTL and UNIQUAC activity coefficient models were determined. To determine the parameters of the model, the isothermal data of Beare and Ramalho measured at 25 °C and 75 °C, respectively, were used, while the non-randomness parameter in the NRTL model was fixed at 0.3. The lowest value of the objective function was obtained by the NRTL model. Finally, model temperature-composition phase diagrams and model equilibrium diagrams were compared with Al-Sahhaf data to check the validity of the models. Small deviations were observed – the model boiling diagrams mostly gave slightly higher dew and bubble points than the experimental ones; the difference was most noticeable at 20,000 Pa, and least noticeable at atmospheric pressure. The model equilibrium diagrams at atmospheric pressure, pressure of 80,000 Pa and 60,000 Pa agreed well with Al-Sahhaf's data, while there were small deviations noticeable at pressures of 40,000 Pa and 20,000 Pa, i.e. at acetone mole fractions greater than approximately 10% the model equilibrium diagrams mostly gave slightly higher dew points and bubble points than experimental ones. |
