Photo-Fenton Degradation of Carbofuran in Helical Tube Microreactor and Kinetic Modeling

The photo-Fenton process is intensified for degradation of carbofuran by using a tubular microreactor coiled around a florescent light. The microreactor attained 7.5 times faster degradation rate compared to a batch reactor operated under a LED light. At the initial Fe2+ concentration of 0.25 mM, the degradation rates in the batch reactor were fast at first, subsequently became slow, and afterward gradually increased with time regardless of light intensity. In the microreactor, the degradation rates appeared to decrease similarly to the first-order reaction despite the same initial Fe2+ concentration. A proposed kinetic model well fitted the results of both batch and microreactors by modeling that Fe3+ is photoreduced in a complex in equilibrium with Fe3+ and intermediates with carboxyl group decomposed from carbofuran.