Technical Note

Determining the Overall Mass Transfer Coefficient for Adsorption of Cu2+ Ions onto Ca-Alginate in Fixed Bed Column

M. Nurbas1*, Y. Kaçar2 and T. Kutsal3

1 Osmangazi University, Chemical Engineering Department, 26480 Eskisehir, Turkey
2 Afyon Kocatepe University, Chemical Engineering Department, 64100 Usak, Turkey
3 Hacettepe University, Chemical Engineering Department, 06532 Ankara, Turkey

Received 22 February 2002; accepted 5 May 2002


In this study, adsorption of trace amounts of dissolved Cu2+ ion was investigated. The polymeric Ca-alginate particles was used as adsorbent. The pH of the solution affected the metal uptake capacity of the Ca-alginate and optimum initial pH of the solution was found as 4 at 25°C constant temperature for this study. The experiments were done at the same volumetric rates and different initial solute concentrations in the fluid. The equilibrium concentration in the fluid, c*, does equal to zero for irreversible adsorption and it is practically zero until the solid concentration is over half the saturation value. The adsorption isotherm of Cu2+ ion onto the above mentioned spherical Ca-alginate particles is indeed sharply convex and the corresponding value of equilibrium concentration, c*, is at a negligible level and the assumption c*=0 is valid. The Cu2+ ion equilibrium concentration is approximate zero even for the maximum adsorbate loading conditions of fixed bed sorption with recycle experiments. The overall mass transfer coefficient of Ke was obtained without the assumption (c/t)=0.

Keywords: adsorption; fixed bed column; heavy metal (Cu2+); overall mass transfer coefficient

* Corresponding author
   E-mail : mnurbas@ogu.edu.tr