Surface and Bulk Measurements of Metals Deposited on Activated Carbon

Diffuse reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning Auger microscopy, elemental analyses, BET surface area, and thermogravimetric analyses have been used to study metals and adsorbed organics on the surface of metal-loaded activated carbon materials. Metals such as copper, zinc, and molybdenum have been deposited on activated carbon via incipient wetness methods. Studies of ground and unground samples show that the organic functional groups such as OH, CH2, CH3, CO, C−O, C−O−C, and CH are exclusively found on the exterior of the metal loaded samples and not in the bulk. Surface studies show that Cu and Zn deposits are on the surface whereas Mo is deposited throughout the bulk of the Mo-loaded activated carbon systems. Surface data for the Cu system suggest the presence of CuCO3 and Cu(OH)2. The Zn species appears to be Zn2+ on the basis of XPS and SAM data. Mo appears to be oxidized, but a specific oxidation state and the oxidic species are not yet able to be determined.