Development of enzymatic, photocatalytic and biological processes for the degradation of micropollutants in municipal and agro-industrial wastewaters

This study is focused on biodegradation of micropollutants using different different enzymatic, photocatalytic and biological process. Various extracellular ligninolytic enzymes were selected and tested for degradation of pharmaceuticals in real wastewater. Ligninolytic enzymes have high degradation potential and been already applied for successful removal of various persistent organopollutants. Direct application of free enzymes into wastewater is not sustainable for a long time, therefore immobilization of the enzymes onto nano- and/or resin particles was performed. Immobilization has shown to stabilize the enzymatic activity. Immobilized enzymes can be applied in batch or packed bed reactors. Photocatalytic and biological processes were optimized in real wastewater samples originated from agro industry. Degradation of fungicides (imazalil and thiabendazole) from fruit and vegetable packaging wastewater will be monitored by LC/UV and removal efficiencies will be calculated. The UV-oxidation step will be carried out using the TiO2 exposed to direct sunlight. Studies have shown that photocatalytic degradation of imazalil and thiabendazole is rapid in distilled water. However, in real wastewater samples the efficiency decreases and optimization is necessary. Biological processes were applied prior to the photocatalytic treatment to improve the efficiency. The operating conditions of these techniques will be optimized for future scaling up at pilot plant.