Comparison of four supports for adsorption of reactive dyes by immobilized Aspergillus fumigatus beads.
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.
Wang
Bao-e
BE
School of Environmental Science and Engineering, South China University of Technology, Guangzhou 510640, China. baoewang@163.com
Hu
Yong-you
YY
D000327:Adsorption; D000464:Alginates / Q000737:chemistry*; D001232:Aspergillus fumigatus; D002266:Carboxymethylcellulose Sodium / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D011142:Polyvinyl Alcohol / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D000464:Alginates; D004396:Coloring Agents; D006603:Hexuronic Acids; D014874:Water Pollutants, Chemical; D020723:Glucuronic Acid; D011142:Polyvinyl Alcohol; D048271:Chitosan; D002266:Carboxymethylcellulose Sodium