ÝKÝLÝ SIVI SÝSTEMLERÝN DÝFÜZYON SABÝTLERÝNÝN BULUNMASI

Ýkili sývý karýþýmlarýnýn difüzyon katsayýlarýnýn (DAB) deneysel olarak hesaplanmasýnda Stokes difüzyon hücresi kullanýldý. Tekrarlanýlabilir sonuçlar alýnýncaya kadar deneyler tekrar edildi. Difüzyon üzerine karýþtýrma hýzýnýn etkisi incelendi. Deneylerde karýþtýrma hýzý olarak 60 devir/dakika seçildi. Difüzyon hücresinin 298 K’de kalibrasyonu 0,1 N potasyum klorür çözeltisinin saf su içine difüzlenmesine göre hesaplandý ve hücre sabiti (?) 0,1997 cm -2 olarak bulundu. Ýkili karýþýmlarýn difüzyon deneyleri 290 K’de termostatlý su banyosunda gerçekleþtirildi. Dimetilftalat-asetik asit, dietilftalat-asetik asit ve benzil alkol-asetik asit sistemlerinin deneysel difüzyon katsayýlarý sýrasýyla 0,927x10 -5cm2/s, 0,613x10-5cm2 /s ve 1,054x10-5cm2/s olarak bulundu. Bunlara ilave olarak Scheibel ve Wilke-Chang metotlarýna göre hesaplanan difüzyon katsayýlarý deneysel deðerler ile karþýlaþtýrýldý.

DIFFUSION COEFFICIENTS OF THE BINARY LIQUID SYSTEMS

A procedure in which Stokes diffusion cell was used is given for the determination of the Stokes diffusion constant for the binary liquid systems. Experiments were repeated until reproducible results were obtained. The effect of stirring on diffusion was examined and the stirring rate of 60 rpm was used in subsequent experiments.The diaphragm of the cell was calibrated at 298 K by diffusing 0.1 N potassium chloride. The experimental cell constant(?) was found 0.1997 cm-2. The binary experiments were performed in a temperature controller water bath at 290 K. The experimental diffusion coefficients of the dimethylphtalate-acetic acid, diethylphtalate-acetic acid and benzyl alcohol-acetic acid were found 0.927x10-5cm2/s, 0.623x10-5cm2/s and 1.067x10-5cm2/s, respectively. Furthermore, diffusion coefficients were calculated by the Scheibel and Wilke-Chang methods and compared with experimental values.