Biossorção de efluente têxtil por biomassa fúngica imobilizada de Aspergillus oryzae e Penicillium citrinum

Abstract

This study evaluated the potential use of inactive filamentous fungi Aspergillus oryzae (AO) and Penicillium citrinum (PC) grown in potato dextrose (BD) and okara-dextrose medium (OkD), immobilized on polyurethane sponge, for biosorption of real textile effluent using flasks and fixed bed column in an exploratory investigation. The real textile effluents were obtained from a local jeans factory and are of unknown composition and concentration due to a trade secret. In the shaking flask tests (170 rpm, 25 °C) different concentrations of textile effluents were treated with varying biomass mass and contact time, and it was observed 83.6 % discoloration for PC-OkD. In a fixed bed column (3 cm internal diameter x 12.7 cm high, 96 mL volume), textile effluent was treated by varying biomass, effluent concentration, ascending flow using commercial peristaltic pump, and time contact, using total recycle configuration, and it was verified 84.9 % discoloration. Desorption with 0.1M NaOH was made. In a fixed bed column, performing two more biosorption-desorption cycles with the same biomass, discoloration decreased from 84.6 % to 55.8 % and 32.9 %. Aliquots taken from the output of the fixed bed column and the conical flasks were analyzed by scanning from 359 nm to 750 nm on a UV-Vis spectrophotometer, using the German environmental parameter DFZ and percentage of discoloration. The biosorbents were characterized by SEM and FTIR, being possible to verify differences between analyzes made before and after contact with textile effluent. Similar studies using the same immobilized and inactivated fungi in the same way have not been found in the literature yet. However, discolouration results of up to 84.9 % are comparable to values ​​found for free live or inactivated filamentous fungi under synthetic dye solution and further studies are required.