Influence of Inorganic Ions and Organic Substances on the Degradation of Pharmaceutical Compound in Water Matrix

Abstract

Abstract:The paper determined the influence of inorganic substances and high-molecular organic compounds on the decomposition of diclofenac, ibuprofen, and carbamazepine in the process of photocatalysis conducted with the presence of Titanium dioxide (TiO 2 ). It was determined that the presence of such ions as CO affected the increase of reaction rate constant value of diclofenac and ibuprofen decomposition. On the other hand, high molecular organic compounds present in the model effluent additionally catalysed the degradation process of pharmaceutical compounds and constituted an additional sorbent that enabled to decrease their concentration. Toxicological analysis conducted in deionized water with pharmaceutical compounds' patterns proved the production of by-products from oxidation and/or reduction of micropollutants, which was not observed for model effluent irradiation.

Removal of Crotamiton from Reverse Osmosis Concentrate by a TiO2/Zeolite Composite Sheet

“…The TiO 2 photocatalysis could be inhibited via the scavenger effect by coexisting ions [10,[38][39][40]. The ions Cl − and HCO 3 − have been found to inhibit photocatalysis through the hydroxyl radical and valence band hole scavenging [10,40].…”

Toxicological analysis of water mixtures of organic micropollutants subjected to UV irradiation

“…All prepared micropollutant water solutions were subjected to UV irradiation for 5, 15, 30 and 60 min. UV light can lead to the decomposition of micropollutants and the formation of several decomposition by-product [14]. Those product can raise the toxic nature of micropollutant water solutions [7].…”

Use of Visible Light Modulation Techniques in Urea Photocatalytic Degradation

“…As expected, the experimental results evidenced that the presence of inorganic ions (Table 1) affects the activity of the photocatalyst active sites, leading to a decrease in photocatalytic performance. One possible reason could be attributed to the competitive adsorption of inorganic ions on the photocatalyst surface, as reported in literature [28]. In fact, since the photocatalytic mechanism is generally based on the reaction of OH • radicals and organic compounds previously adsorbed on the photocatalyst surface, the decrease of organic compound's adsorption could be one of the main causes of the decrease in photocatalytic activity [29].…”

“…This aspect that commonly leads to a decrease of photocatalytic activity is well discussed in literature [27]. In particular, the authors attributed this phenomenon to [28]: (i) a competitive adsorption of inorganic ions on the photocatalyst surface, which consequently blocks adsorption sites for the target molecules; and to (ii) a possible scavenging effect of the adsorbed inorganic ions, which consume photogenerated holes with a consequent decrease in photocatalytic efficiency.…”