UPTAKE INTO CHITOSAN HYDROGEL BEADS

Todd Scheele, Dr. Raj Jain, Jason Todd, Dr. Wolfgang Glasser
National Science Foundation and Technology Center:
High Performance Polymeric Adhesive and Composites, and
Department of Wood Sciences
Virginia Polytechnic Institute and State University
Blacksburg, Virginia

ABSTRACT

Chitosan hydrogel beads were used to uptake copper from an aqueous solution [2ppm-50ppm] in batch and continuous processes. A batch experiment, called interruption test showed there to be an nonreversible complex formed between the chitosan and copper. This also showed there to be no particle diffusion which is also conclusive with the large pore size, 600 nm, found in the transmission electron microscope photos. The greatest dynamic load capacity, (meq of copper uptake by column before breakthrough) was 0.023meq/g-bead for 1.7% solid beads at an absolute velocity of 1.1 cm/min. This was 1.5 times any seen for 3.1% solid beads. With the increase in copper concentration the beads size was discovered shrink by 13%. Some regeneration of beads was observed by use of a stronger complex agent than the copper chitosan complex, which drove the copper out of the beads and into the surrounding solution containing the stronger complex agent.