The pH effect on the kinetics of 4-nitrophenol removal by CWPO with doped carbon black catalysts

Catalysts Prepared with Matured Compost Derived from Mechanical-Biological Treatment Plants for the Wet Peroxide Oxidation of Pollutants with Different Lipophilicity

“…Additionally, C-400 and C-800 show an induction period close to 2 h, in which the conversions of 4-NP are negligible. In a previous work dealing with the CWPO of 4-NP with carbon black as the catalyst, an induction period close to 2 h was also observed, which was mitigated decreasing the initial pH from 3 to 2 or by increasing the temperature of the reaction from 50 to 80 °C [23]. The contribution of adsorption in removing 2-NP with all materials tested was not higher than 8% after 24 h of contact time, as determined by pure adsorption runs at the same operating conditions, but without H 2 O 2 .…”

“…Additionally, C-400 and C-800 show an induction period close to 2 h, in which the conversions of 4-NP are negligible. In a previous work dealing with the CWPO of 4-NP with carbon black as the catalyst, an induction period close to 2 h was also observed, which was mitigated decreasing the initial pH from 3 to 2 or by increasing the temperature of the reaction from 50 to 80 • C [23]. Regarding the catalysts treated with sulfuric acid (C-800-S, C-S-800, and C-800-S-800), these materials show higher 4-NP degradation rates at the beginning of the reaction (X4-NP = 44−67% after 30 min), likely due to its acidic character (Table 2).…”

“…The CWPO runs with 2-NP and 4-NP were carried out in a batch system using a 500 mL magnetically stirred (600 rpm) round-bottom flask as reactor, equipped with a condenser and a heating bath [23]. Briefly, 100 mL of the target pollutant solution was first loaded to the reactor and then heated to 50 • C. Upon stabilizing the temperature, the solution pH was adjusted to the initial pH (pH 0 ) of 3 using a 1 M H 2 SO 4 solution, and the selected quantity of catalyst (2.5 g L −1 ) was then loaded to the aqueous solution.…”

Carbon-Based Materials for Oxidative Desulfurization and Denitrogenation of Fuels: A Review

“…(ii) There is also a lack of reports testing carbon-based materials as catalysts on their own containing dopants other than oxygen. Nitrogen, phosphorus, and sulfur are all possible dopants that have been shown to increase catalytic activity in aqueous phase oxidation reactions [64,[170][171][172]. (iii) Denitrogenation approaches are much less common, and there is still the opportunity to study denitrogenation reactions, mainly aiming at simultaneous high removals of N and S-containing compounds.…”

Kinetic insights on wet peroxide oxidation of caffeine using EDTA-functionalized low-cost catalysts prepared from compost generated in municipal solid waste treatment facilities

“…Aiming to increase catalytic performance in CWPO, modification of catalytic materials have been widely explored by functionalization (Ribeiro et al, 2013) and doping with heteroatoms (Diaz de Tuesta et al, 2020b;Martin-Martínez et al, 2016) and metals, mainly iron (Anis and Haydar, 2018;Motuzas et al, 2018). These strategies introduces additional electron donating abilities to the materials, improving its efficiency for the decomposition of hydrogen peroxide into hydroxyl radicals (Zhu et al, 2019).…”