Simulation and Optimization of the CWPO Process by Combination of Aspen Plus and 6-Factor Doehlert Matrix: Towards Autothermal Operation

Abstract

This work aims to present an industrial perspective on Catalytic Wet Peroxide Oxidation (CWPO) technology. Herein, process simulation and experimental design have been coupled to study the optimal process conditions to ensure high-performance oxidation, minimum H2O2 consumption and maximum energetic efficiency in an industrial scale CWPO unit. The CWPO of phenol in the presence of carbon black catalysts was studied as a model process in the Aspen Plus® v11 simulator. The kinetic model implemented, based on 30 kinetic equations with 11 organic compounds and H2O2 involvement, was valid to describe the complex reaction network and to reproduce the experimental results. The computer experiments were designed on a six-factor Doehlert Matrix in order to describe the influence of the operating conditions (i.e., the different process temperatures, inlet chemical oxygen demands, doses of H2O2 and space time) on each selected output response (conversion, efficiency of H2O2 consumption and energetic efficiency) by a quadratic model. The optimization of the WPO performance by a multi-criteria function highlighted the inlet chemical oxygen demand as the most influential operating condition. It needed to have values between 9.5 and 24 g L−1 for autothermal operation to be sustained under mild operating conditions (reaction temperature: 93–130 °C and pressure: 1–4 atm) and with a stoichiometric dose of H2O2.

Assessment of Pretreatments for Highly Concentrated Leachate Waters to Enhance the Performance of Catalytic Wet Peroxide Oxidation with Sustainable Low-Cost Catalysts

“…Although mineralization was not itself as high as when using PC, as mentio fore, efficient use of H2O2 may impact the cost of the CWPO unit [44]. The main di observed with ηH 2 O 2 when using PC or HC catalyst may be ascribed to the slower position of H2O2 when applying HC (as shown in Figure 6).…”

“…It can be concluded that the objective was achieved, as in the CWPO reactions conducted with either PC or HC, an improvement in η H 2 O 2 was observed, which means that fewer parallel reactions other than organic matter oxidation took place. Since in a CWPO unit, H 2 O 2 is the main operational cost [44], conditions that result in a more efficient decomposition of the oxidant source are considered a key step in developing suitable CWPO processes [44].…”

“…The efficiency of H 2 O 2 consumption (η H 2 O 2 ) was calculated considering the amount of H 2 O 2 necessary to oxidize 1 mol of carbon, as described in a previous work related to CWPO [44] (Equation ( 5)).…”

Carbon Nanomaterials from Polyolefin Waste: Effective Catalysts for Quinoline Degradation through Catalytic Wet Peroxide Oxidation

“…Among AOPs, catalytic wet peroxide oxidation (CWPO) can be highlighted due to its low cost and mild operation [10]. CWPO relies on the formation of highly oxidizing hydroxyl radicals from hydrogen peroxide through the action of a suitable catalyst [11]. CWPO has been tested for the oxidation of several organic compounds with distinct catalysts [12][13][14][15][16], showing effective results in the degradation of organic pollutants.…”

Performance of metal-free carbonaceous catalysts in the removal of paracetamol by catalytic wet peroxide oxidation

“…Considering that the running cost of a CWPO unit is mainly due to H2O2 consumption (Diaz de Tuesta et al, 2020), an efficient H2O2 consumption represents a fundamental parameter to be assessed to avoid the formation of molecular oxygen (Ribeiro et al, 2013). In this context, the efficiency of hydrogen peroxide consumption, determined as specified in Eq (1), was good for both catalysts, with advantage for Mon11F, probably because the catalyst favours the efficient use of radicals HO • , HOO • and O2 •to oxidize the organic matter, instead of leading to undesirable side reactions, enabling more efficient utilization of the oxidant.…”