Kinetic and thermodynamic study on the liquid phase adsorption by starchy materials in the alcohol-water system

Improving adsorptive processes demands a constant search for new adsorbents. In the case of alcohol-water separation, zeolites are widely used. The use of new adsorbents as a substitute for zeolites, mainly starch, has been proposed recently. This work is a thermodynamic and kinetic study of liquid phase adsorption of water from methanol, ethanol, propanol and butanol-water mixtures using starch as the adsorbent. The thermodynamic data were obtained by means of the static method at three different temperatures (25, 40 and 50degreesC), and were correlated by the Langmuir isotherm. The kinetic data were obtained in a finite liquid bath cell. The influence of temperature and molecular chain length of the alcohol on the capacity and adsorption rate were determined.