Influence of Inorganic Compounds on the Process of Photocatalysis of Biologically Active Compounds

Constant increase in concentration of organic micropollutants in the water environment influences the development of methods for their effective elimination from various matrices released into aquatic ecosystems. One of widely described in literature processes for the decomposition of hardly-biodegradable pollutants is the process of heterogeneous photocatalysis. The paper presents the influence of inorganic substances on the decomposition of polycyclic aromatic hydrocarbons (anthracene and benzo[a]pyrene), industrial admixtures – octylphenol and pharmaceutical compounds – diclofenac in the photocatalysis process conducted in the presence of TiO₂. It has been shown that the presence of Cl^– ions did not affect the photochemical reaction of the micropollutant decomposition. Whereas, the presence of CO₃^2–, SO₄^{2– and HPO₄2– ions inhibited the decolonization of octylphenol and diclofenac, while the degradation efficiency of anthracene and benzo[a]pyrene was reduced only by the presence of CO₃2– and HCO₃ – anions. The photooxidation of micropollutants in solutions containing Al3+ oraz Fe3+ cations proceeded with a much lower efficiency than that for solution without inorganic compounds. The analysis of the kinetics of the photocatalytic decomposition of selected micropollutants show a decrease in the reaction rate constant and an increase in their half-life due to the blocking of theactive semiconductor centers by inorganic compounds. In addition,the toxicological analysis inducated the generation of micropollutant oxidation by-products, which aggravate the quality of treated aqueous solutions.}