Studies on the Kinetics of Doxazosin Degradation in Simulated Environmental Conditions and Selected Advanced Oxidation Processes

Abstract

The photochemical behavior of doxazosin (DOX) in simulated environmental conditions using natural waters taken from local rivers as a solvent was studied. The chemical characteristics of applied waters was done and a correlation analysis was used to explain the impact of individual parameters of matrix on the rate of the DOX degradation. It was stated that DOX is a photoliable compound in an aqueous environment. Its degradation is promoted by basic medium, presence of environmentally important ions such as Cl−, NO3−, SO42− and organic matter. The kinetics of DOX reactions with OH− and SO4− radicals were examined individually. The UV/H2O2, classical Fenton and photo-Fenton processes, were applied for the generation of hydroxyl radicals while the UV/VIS:Fe2(SO4)3:Na2SO2 system was employed for production of SO4− radicals. The obtained results pointed that photo-Fenton, as well as UV/VIS:Fe2(SO4)3:Na2SO2, are very reactive in ratio to DOX, leading to its complete degradation in a short time. A quantitative density functional theory (DFT) mechanistic study was carried out in order to explain the molecular mechanism of DOX degradation using the GAUSSIAN 09 program.

Preparation of Iron-Loaded Granular Activated Carbon Catalyst and Its Application in Tetracycline Antibiotic Removal from Aqueous Solution

“…The degradation mechanism of antibiotics by a heterogeneous catalyst in the Fenton reaction has been reported in previous studies [48,49,50,51]. Overall, the main steps for tetracycline antibiotics by GAC-Fe with the catalysis of H 2 O 2 were as follows.…”

Kinetics and Mechanistic Studies of Photochemical and Oxidative Stability of Galaxolide

“…To provide accurate description of the properties of the transition states and reactive intermediates the M06-2X functional, designed especially for chemical kinetics [44], was employed in conjunction with Dunning's correlation-consistent polarized valence basis set [3s2p1d/2s1p], denoted as cc-pVDZ [45]. This theory level was previously proven as a useful tool to capture the physical change along with the reaction coordinate for this type of reactions [46]. Normal mode analysis was performed to ensure the characteristics of the stationary points, i.e., the stable structure has zero imaginary ("negative") vibrational frequency, whereas the transition states (TS) have one and only one imaginary mode, corresponding to its reaction coordinate.…”

Removal of Organic Pollution in the Water Environment

“…The Special Issue consists of nine papers describing a wide spectrum of research related to the removal of environmentally significant pollutants from aqueous samples and their determination in various matrices. The presented articles can be classified into three broad thematic sectors related to the topic of the special issue: new methods of isolation and determination of compounds from the EOCs group [22][23][24], occurrence of EOCs in the water environment [24,25], and new approaches to the degradation of significant water pollutants or their removal [26][27][28][29][30].…”

“…A very low oxidation efficiency of the test compound was observed when the sulfate electrolyte was used in combination with both BDD and platinum electrodes. Karpinska et al [28] describes detailed studies on the kinetics of the degradation processes of doxazosin (DOX) under the influence of sunlight in environmental conditions and some advanced oxidation processes (AOPs). Doxazosin is a biologically active compound used for the treatment of some prostate complaints and hypertension.…”

“…Its efficiency strongly depends on the presence of electron and hole scavengers and the chemical properties of adsorbed organic compounds. The above articles [27][28][29] concern the application of chemical processes for removal of organic pollutants. Another approach to wastewater cleaning was proposed by Mendoza et al [30].…”