Hydrodenitrogenation

The hydrodenitrogenation , HDN is short, a refining process for removing nitrogen from organic nitrogen compounds of various petroleum fractions . Organic nitrogen compounds can damage the catalysts of the various conversion processes in refineries. When they are burned, they also produce environmentally harmful nitrogen oxides .

Raw materials and products

Typical organic nitrogen compounds found in petroleum are quinolines and porphyrins and their derivatives. These are of biological origin. The total nitrogen content is usually less than 1%. The aim of dehydronitrogenation is levels in the ppm range.

By hydrodenitrogenation arise from organic nitrogen compounds by reduction with hydrogen using a heterogeneous catalyst , both nitrogen-free hydrocarbons and ammonia according to the reaction equation:

${\displaystyle \mathrm {R_{3}N\ +3\ H_{2}\longrightarrow 3\ RH+\ NH_{3}} }$

Reaction engineering

The catalyst often consists of cobalt and nickel or molybdenum disulfide , sometimes also tungsten disulfide , on aluminum oxide or silicon dioxide as a carrier. A high surface area is desired for hydrogenation catalysts . The exact composition of the catalysts is adapted to the application if necessary.

The hydrodenitrigenation takes place as part of the general hydrogen treatment , the hydrotreating of the petroleum components, in which, in addition to nitrogen, above all sulfur and in some cases also oxygen are removed from the raw material.

literature

• Toshiaki Kabe, Atsushi Ishihara, Weihua Qian: Hydrodesulfurization and Hydrodenitrogenation . Wiley-VCH, 2000, ISBN 978-3-527-30116-4 (Hardcover).

Individual evidence

1. ^ Roel Prins: Hydrotreating . In: Handbook of Heterogeneous Catalysis . Wiley-VCH, 2008, p. 6, doi: 10.1002 / 9783527610044.hetcat0137 .
2. ↑ Jens Hagen: Technical Catalysis - An Introduction . VCH, 1996, ISBN 3-527-28723-X , pp. 178-179.