REMOVAL OF HUMIC SUBSTANCES FROM AQUEOUS-SOLUTION BY FUNGAL PELLETS

The removal of humic substances from aqueous solution at pH=4.8 and 6. 0 and 25 degrees C by pure culture of Aspergillus niger has been exami ned. The removal of humic substances from aqueous phase was monitored by following the decrease in absorbance at 370 nm. COD and fungal grow th were also measured. The initial concentration of humic and fulvic a cids, pH and diameter of fungal pellets were found to be the most impo rtant parameters. The results suggested that decolorization of batch c ulture was a consequence of several processes. In the first 5 hours fo r pellets with diameter 1-3 mm and 10 hours for pellets with diameter 2-5 mm adsorption of humic substances was dominant. Afterwards, desorp tion of slightly bound humic substances and their degradation, as well as degradation of remaining humic substances in the solution, continu ed simultaneously through the period of 10 days.