Non-isothermal Kinetics of Benzo[a]pyrene Photooxidation in Glyceryl Trioctanoate

článek v časopise ve Web of Science, Jimp

angličtina

Benzo[a]pyrene (BaP) was dissolved in glyceryl trioctanoate, heated in a glass reaction vessel within temperature range 303.15 – 473.15 K at the heating rates of 0.1, 0.2, 0.5, 1 and 2 K/min and simultaneously exposed to UV light at the wavelength = 365 nm and at the radiation power 20 mW cm-2 in order to study the decrease of BaP concentration due to its photooxidation. Reaction mixture was sampled at temperature increments of 10 K and the concentration of BaP was determined by HPLC-FD. As observed, the BaP concentration decreased from initial 100 mikrog/l in dependence on the heating rate. From the experimental results, the kinetic parameters (A = (2.8 + 5.9) x 10-14 /min, D = (5.86 + 0.43) x 10-2 /K) describing the kinetics of BaP photooxidation have been obtained. Knowing the kinetic parameters, modelling of the photooxidation for any time/temperature regime is feasible without a deeper insight into the mechanism of the process. 20 mW cm2 in order to study the decrease of BaP concentration due to its photooxidation. The concentration of BaP was determined by HPLC-FD periodically in 5 min intervals. As observed, the BaP concentration decreased from 62.2 mikrog L-1 to 19.8 mikrog L-1. From the experimental results, the parameters characterizing the non-isothermal kinetics of BaP photooxidation have been obtained. The parameters were tested at two various isothermal conditions (290.16 and 323.26 K) to verify a suitability of derived parameters. Comparing calculated and measured data of half-lives of BaP decrease at mentioned temperatures it was found that calculated half-lives are in a good accordance with those experimentally obtained values, when relative standard deviations at 290.16 K were 17.0% and 5.4% at 323.26 K, respectively. The kinetic parameters enable the calculation of the rate constant for any temperature in isothermal regime and make possible to model, in general, the kinetics of such processes without a deeper insight into their mechanisms

benzo(a)pyrene, kinetics

SKLÁRŠOVÁ, B.; ŠIMON, P.; KOLEK, E.; ŠIMKO, P.; BEDNÁRIKOVÁ, A.

2012

14. 9. 2012

Taylor & Francis Group, LLC

Philadelphia, PA 19106 USA

1040-6638

Polycyclic Aromatic Compounds

32

3

Spojené království Velké Británie a Severního Irska

580

588

9