Some studies of cadmium adsorption using Aspergillus niger, Penicillium austurianum, employing an airlift fermenter

Aspergillus niger and Penicillium austurianum were produced on a rotary shaker washed, dried, and sieved. The 1g of each biomass were introduced into tiny columns and Erlenmeyer flasks of 50 ml volume, to study the effect of agitation, cadmium in solution concentration and a wide range of pH. The samples were analyzed using atomic absorption spectroscopy (Shimadsu AA67) at 228.8 nm. The adsorption data of A. niger were fitted to Langmuir and Freundlich models and R-2 higher than 0.97 and 0.98 obtained. In a different set of experiments the effects of cadmium concentration in solution, temperature, aeration velocity and mixed culture of 1: 1 and 3: 1 ratio employing a glass made airlift fermenter were investigated. The results show that the operation temperature of 22 +/- 1 degreesC and pH 4 and 5 are suitable for biosorption, using active fungi. It was also found that 2 vvm aeration is reasonably sound to produce biomass and biosorption using A. niger in the airlift reactor. (C) 2002 Elsevier Science B.V. All rights reserved.