engleski

Laccase catayzed phenol oxidation in microreactor

Phenols and its compounds are widely used in chemical, pharmaceutical, cosmetic and food industries. Although a small amount of phenols is found in pharmaceuticals, such as aspirin, process wastewater contaminated with phenols, because of its extreme toxicity, represent a significant burden on the environment. Therefore, such industrial wastewater should be treated before discharging into the natural receivers. Wastewaters loaded with phenols are usually treated by a variety of chemical and biochemical processes in different configurations of macroreactors. Recently, use of microreactor was intensified for the reactions involving hazardous chemicals. Microreactors are the reactor systems constructed of microchannels, with typical dimensions of 10-500 μL engraved in tiles made of glass, silicone or various polymers. Their small dimensions resulted in a huge area to volume ratio and a small residence time, resulting in an intense transfer of mass and energy compared to conventional macroreactors. Application of microreactors allows precise control of the process, a small amount of the reactants and catalyst used, a small number and quantity of the waste streams. Therefore microreactors are highly suitable for the implementation of exothermal and endothermal reactions, as well as reactions that use hazardous or explosive chemicals. In this work, oxidation of phenol from the model waste water, catalyzed by the enzyme lacasse in microreactor was performed. The effects of geometry, the length of the microreactor channel, the influence of substrate aeration by air or oxygen for different residence time on the conversion of phenols were studied. 6 μL and 13 μL microreactors were used, with two “Y”-shaped inlet streams and one outlet stream. One entrance was used for the aqueous solutions of phenol and the other for the aqueous solutions of laccase. The highest conversion of X = 17.82 % was achieved in 6 μL microreactor for the retention time of 36 seconds when the model solution was aerated by oxygen.

microreactor; phenol; laccase; oxidation

Ovaj se tekst temelji na radu koji je financirala Nacionalna zaklada za znanost, visoko školstvo i tehnologijski razvoj Republike Hrvatske.