Nm. Hassan et al., ADSORPTION OF N-PARAFFIN WAX FROM ISOOCTANE SOLUTION ON CRYSTALLINE UREA, Separation science and technology, 29(7), 1994, pp. 897-906
Equilibrium isotherms and kinetics of adsorption of n-paraffin wax fro
m isooctane solution on crystalline urea were obtained at 50 and 70-de
grees-C and at 50, 70, and 90-degrees-C, respectively. The equilibrium
data were correlated according to the Polanyi potential theory, which
provided a single characteristic curve of the experimental data at tw
o temperatures. The batch kinetic data suggest that the adsorption of
n-paraffin wax on crystalline urea is diffusion controlled. Effective
diffusion coefficients derived from fractional uptake versus time were
in the order of 10(-14) to 10(-13) cm2/s. The apparent activation ene
rgies of diffusion decreased with increasing uptake, as expected.