Author(s): Roman, Fernanda ; Díaz de Tuesta, Jose Luis ; Silva, Adrián ; Faria, Joaquim ; Gomes, Helder
Date: 2021
Persistent ID: http://hdl.handle.net/10198/27245
Origin: Biblioteca Digital do IPB
Subject(s): Nitrogenated compounds; Research Subject Categories::TECHNOLOGY::Chemical engineering::Food technology
Nitrogenated compounds are naturally found in petroleum-based products. Upon their combustion, hazardous gases (NOx) are generated, leading to environmental and health issues. To overcome the downsides related to nitrogen oxides,1 catalytic oxidative denitrogenation (ODN) with H2O2 is currently seen as a suitable alternative to traditional hydrodenitrogenation. In this work, the catalysts for ODN consisted of carbon nanotubes synthesized from low-density polyethylene as a carbon source by chemical vapor deposition (850 °C, 1 h). A simulated fuel was prepared by dissolving quinoline (QN) in 2,2,4- trimethylpentane ([N]0 = 50 ppm, [QN]0 = 460 ppm). ODN was carried out in an emulsified system (80:20 2,2,4-trimethylpentane:water, Vtotal = 20 mL) at 50 °C, 4 h, Ccatalyst = 2.5 g L- 1 and VH2O2, 30 wt.% = 0.9 mL (5.5× the stoichiometric ratio for QN mineralization). The emulsion was formed by sonication for 15 min. The obtained results are summarized in Fig. 1. ODN carried out at the initial pH (pH0) 3.5 resulted in 74% of QN removal from the oil phase, which is far higher when compared to only 15% removal occurring by mass transference (test conducted with an aqueous phase free of H2O2 and catalyst). At pH0 = 6.5, QN removal from the oil phase decreased drastically to 33%, indicating that a lower pH favor QN removal.
