Macroporous Cellulose-Tungsten Carbide Composite Beads for Expanded Bed Adsorption

摘要

A new kind of macroporous cellulose beads densified by tungsten carbide were prepared through the method of water-in-oil suspension thermal regeneration. The cassava starch was used innovatively as additive component during the preparation to enlarge the pore size. After the forming of cellulose beads the composite starch could be eliminated with heat treatment and enzymatic hydrolyzation. The sphericity of cellulose beads was not influenced by starch addition and 1-3 |ì m diameter pores could be formed in the beads. Varieties of some properties such as wet density, water content, porosity, specific surface area and mean pore diameter of the composite beads as the function of starch addition were investigated. With the gel filtration test, prepared macroporous beads showed better pore diffusion especially for large-size protein, which indicated the advantage of macropore for the operation under high flow rate. In addition, the prepared beads showed good expansion and stability in expanded bed, and are suitable for expanded bed applications.