A practical time discretization methodology for adjusting the dosage profile in photo-Fenton processes
Authors: Perez-Moya Montserrat , Xiangwei Yu , Graells Moisès 
Published: November 2022

Photo-Fenton processes are effective for mineralizaing aqueous solutions containing emergent pollutants. Accordingly, a number of works has been dedicated to determining conditions enhancing their performance (Pouran et al.,2015; Wang et al.,2016).

Despite improvements, solutions are still far from optimal. Using H2O2 is essential, but excess is recognized counterproductive. Hence, research sought for adequate concentration ratios of H2O2 to contaminant and iron (Pignatello et al.,2006).

Constant ratios suit steady operation, but time-varying batch processes require H2O2 concentration to be controlled to maximize performance. Thus, optimizing H2O2 dosage challenges current research.

Experimental tuning of pre-established protocols systematically improves the dosage profile of photo-Fenton processes (Yamal et al., 2012), but considering too few degrees of freedom produces solutions too far from optimal.

Conversely, the lack of detailed dynamic models hinders model-based optimization (Jung et al., 2015). Success cases have been reported for polymerization reactors (Jang et al., 2016; Nie et al., 2014), but recipe optimization of photo-Fenton processes has been hardly addressed (Audino et al., 2019).

Using recipe optimization concepts and a practical time discretization, a methodology is proposed for experimentally optimizing the dosage profile. Results show the practicability of the solution, and discussion provides insight for the generalization of an optimization procedure.

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