Characterization and adsorption study of acetaldehyde on supported metals/active carbon systems

It was observed that the micropore volume of active carbon decreases with increasing amount of metal (Ni, Cu, Cd, Zn) in the carbon lattice. A temperature programmed reduction study indicated that active carbon acts as a dispersing agent and metal residues are present on the surface in dispersed form. A detailed examination of nitrogen adsorption indicated differences in the mode of dispersion of these metals. The effect of metal on the adsorption behavior of active carbon for acetaldehyde was also studied as a function of temperature. From the adsorption data, thermodynamic parameters such as free energy, entropy and enthalpy of adsorption were calculated from a virial isotherm expression. It was observed that supported metal/active-carbon systems exhibit greater adsorption affinity than expected from the sum of the individual constituents.