Surface modification of alumina by metal doping

A series of metal impregnated alumina samples were prepared by incipient we tness impregnation technique. Pore structure and surface area for metal dop ed alumina (Cr, Mn, Fe and Co) containing different concentration of metals was assessed by mercury penetration and low temperature nitrogen adsorptio n. It was observed that mercury intrusion and extrusion curves are irrevers ible giving the evidence of 'ink bottle' pores in the alumina samples. From comparison of results of mercury porosimeter, it was also noted that total pore area values decreased with increasing metal concentration. Nitrogen a dsorption data revealed that surface area decreased with increasing metal f raction (due to dispersion of metal residues on the surface of alumina samp les). On the other hand, metal concentration per unit area increased with i ncreasing the amount of metal used in doping. (C) 2000 Elsevier Science B.V . All rights reserved.