The structure and function of supported molybdenum nitride hydrodenitrogenation catalysts

Journal Article · Tue Mar 01 04:00:00 EST 1994 · Journal of Catalysis; (United States)

DOI:https://doi.org/10.1016/0021-9517(94)90022-1· OSTI ID:6859139

Colling, C W; Thompson, L T ^[1]

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1. Univ. of Michigan, Ann Arbor, MI (United States)

A series of [gamma]-Al[sub 2]O[sub 3] supported Mo nitrides wee prepared by the temperature programmed reaction of supported molybdates with NH[sub 3]. Several loadings, heating rates, and space velocities were employed in an attempt to vary the properties of the nitride. The structure and composition of the supported nitrides depended on the structure of the precursor oxide and the conditions employed in nitriding the oxide. The ease with which the oxide was nitrided improved with increasing Mo loading. Nitride domains in the low-loaded materials (4 and 8 wt% Mo) were highly dispersed and X-ray amorphous while the higher-loaded catalysts (16 wt% Mo) consisted to [gamma]-Mo[sub 2]N crystallites. The response of the high-loaded materials to the various nitriding conditions was similar to that observed for unsupported [gamma]-Mo[sub 2]N. The supported Mo nitrides were active for the hydrodenitrogenation of pyridine. In fact, their activities were superior to that of a commercial sulfided Ni-Mo hydrotreating catalyst and comparable to those of the unsupported Mo nitrides. The catalytic properties of the supported Mo nitrides depended on the size and composition of the Mo nitride domains. The authors believe that the most active sites were located at the perimeters of two-dimensional, raft-like domains. Regions near the perimeter also appeared to be nitrogen deficient. Lower activity sites were associated with the [gamma]-Mo[sub 2]N crystallite surfaces. 22 refs., 6 figs., 6 tabs.

• DOE Contract Number: FG22-92PC92537
• OSTI ID: 6859139
• Journal Information: Journal of Catalysis; (United States), Journal Name: Journal of Catalysis; (United States) Vol. 146:1; ISSN 0021-9517; ISSN JCTLA5
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400 -- Petroleum-- Processing
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
AZINES
CATALYSIS
CATALYST SUPPORTS
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL PREPARATION
CHEMICAL REACTIONS
DENITRIFICATION
ELECTROMAGNETIC RADIATION
GAMMA RADIATION
HETEROCYCLIC COMPOUNDS
HETEROGENEOUS CATALYSIS
HYDROGENATION
IONIZING RADIATIONS
MOLYBDENUM COMPOUNDS
MOLYBDENUM NITRIDES
NITRIDES
NITROGEN COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
PYRIDINE
PYRIDINES
RADIATIONS
REFRACTORY METAL COMPOUNDS
STRUCTURAL CHEMICAL ANALYSIS
SYNTHESIS
TRANSITION ELEMENT COMPOUNDS