Comparison of four supports for adsorption of reactive dyes by immobilized Aspergillus fumigatus beads

J Environ Sci (China). 2007;19(4):451-7. doi: 10.1016/s1001-0742(07)60075-8.

Abstract

Four materials, sodium carboxymethylcellulose (Na-CMC), sodium alginate (SA), polyvinyl alcohol (PVA), and chitosan (CTS), were prepared as supports for entrapping fungus Aspergillus fumigatus. The adsorption of synthetic dyes, Reactive Brilliant Blue KN-R, and Reactive Brilliant Red K-2BP, by these immobilized gel beads and plain gel beads was evaluated. The adsorption efficiencies of Reactive Brilliant Red K-2BP and Reactive Brilliant Blue KN-R by CTS immobilized beads were 89.1% and 93.5% in 12 h, respectively. The adsorption efficiency by Na-CMC immobilized beads was slightly lower than that of mycelial pellets. But the dye culture mediums were almost completely decolorized in 48 h using the above-mentioned two immobilized beads (exceeding 95%). The adsorption efficiency by SA immobilized beads exceeded 92% in 48 h. PVA-SA immobilized beads showed the lowest adsorption efficiency, which was 79.8% for Reactive Brilliant Red K-2BP and 92.5% for Reactive Brilliant Blue KN-R in 48 h. Comparing the adsorption efficiency by plain gel beads, Na-CMC plain gel beads ranked next to CTS ones. SA and PVA-SA plain gel beads hardly had the ability of adsorbing dyes. Subsequently, the growth of mycelia in Na-CMC and SA immobilized beads were evaluated. The biomass increased continuously in 72 h. The adsorption capacity of Reactive Brilliant Red K-2BP and Reactive Brilliant Blue KN-R by Na-CMC immobilized beads was 78.0 and 86.7 mg/g, respectively. The SEM micrographs show that the surface structure of Na-CMC immobilized bead is loose and finely porous, which facilitates diffusion of the dyes.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Alginates / chemistry*
  • Aspergillus fumigatus*
  • Carboxymethylcellulose Sodium / chemistry*
  • Chitosan / chemistry*
  • Coloring Agents / chemistry*
  • Glucuronic Acid / chemistry
  • Hexuronic Acids / chemistry
  • Polyvinyl Alcohol / chemistry*
  • Water Pollutants, Chemical / chemistry*

Substances

  • Alginates
  • Coloring Agents
  • Hexuronic Acids
  • Water Pollutants, Chemical
  • Glucuronic Acid
  • Polyvinyl Alcohol
  • Chitosan
  • Carboxymethylcellulose Sodium