Novel Methodology toward Deep Desulfurization of Diesel Feed Based on the Selective Elimination of Nitrogen Compounds

Abstract

π-Acceptor molecules covalently attached on hydrophilic support were used to selectively remove neutral nitrogen heterocyclic compounds from diesel feed by a charge transfer mechanism. Functionalized hydrophilic polymers can effectively adsorb nitrogen heterocyclic compounds with a high selectivity toward sulfur heterocyclic compounds from model and real feed. The results showed that charge transfer processes coupled with an ion-exchange process to selectively remove basic nitrogen compounds are efficient enough to produce denitrogenated feed in high yield. This study was conducted to determine whether trends in hydrodesulfurization (HDS) activity with lower sulfur content were mainly the result of lower reactivity of hindered sulfur compounds or due to nitrogen species inhibition. The inhibition effects of nitrogen compounds on HDS at conditions commonly used in the hydrotreatment of gas oil feedstocks has been experimentally determined. This study suggests that the selective removal of nitrogen compounds from gas oil strongly enhanced the deep desulfurization.

Removal of nitrogen compounds from liquid hydrocarbon streams by selective sorption on metal-organic framework MIL-101

“…[3][4][5] It was shown that the removal of nitrogen compounds from the middle-distillate oil significantly improve HDS performance, allowing one to achieve an ultra deep HDS under mild conditions using conventional catalysts. 6 The removal of nitrogen compounds by adsorption at ambient temperature is a promising approach. The adsorption of nitrogen compounds by well-known porous materials such as activated carbons, 7-9 activated alumina, 8,9 silica-based adsorbents 10,11 and zeolite-based materials 12,13 was studied ( Table 1).…”

Polyoxometalate (POM)-Layered Double Hydroxides (LDH) Composite Materials: Design and Catalytic Applications

“…In addition to sulfur compounds, diesel oil, gasoline and jet fuel contain many nitrogen-containing compounds [49]; the combustion of these substances will release large amounts of nitrogen oxides, leading to the formation of acid rain with serious environmental consequences [50]. Although the concentration of nitrogen-containing compounds in fuel oils is relatively low, the competition with sulfur-containing components for the active sites of the catalysts [51,52], can lead to the inhibition of the deep desulfurization process. Therefore, deep desulfurization and denitrogenation is of great significance for the development of clean oil products, and is a challenging task.…”

“…Although the concentration of nitrogen-containing compounds in fuel oils is relatively low, the competition with sulfur-containing components for the active sites of the catalysts [51,52], can lead to the inhibition of the deep desulfurization process. Therefore, deep desulfurization and denitrogenation is of great significance for the development of clean oil products, and is a challenging task.…”

Iminium cations as intermediates in the hydrodenitrogenation of alkylamines over sulfided NiMo/γ-Al2O3

“…(C 5 ) 3 N, C 5 -SH, and C 5 -NH 2 are formed as primary products by disproportionation and substitution of the reactants (similar to Eqs. (1) and (3)). C 1 -N(C 6 ) 2 reacted by substitution to C 1 -NH-C 6 , C 6 -NH-C 6 , and C 6 -SH as primary products (Eqs.…”

“…Nitrogen-containing compounds are harmful in deep HDS, as they inhibit the adsorption of sulfur-containing compounds [1][2][3] and, therefore, it is important to know how hydrotreating catalysts remove nitrogen-containing molecules.…”