Formation, structure, and HDN activity of unsupported molybdenum phosphide

Journal Article · Tue Apr 25 04:00:00 EDT 2000 · Journal of Catalysis

DOI:https://doi.org/10.1006/jcat.1999.2808· OSTI ID:20030525

Stinner, C; Prins, R; Weber, T

A molybdenum phosphide catalyst was prepared from an aqueous solution of (NH{sub 4}){sub 6}Mo{sub 7}O{sub 24} {center_dot} 4H{sub 2}O (NH{sub 4}){sub 2}HPO{sub 4} by precipitation, calcination, and subsequent reduction in H{sub 2} at 923 K. Raman spectroscopic measurements revealed that the aqueous solution contained MoO{sub 4}{sup 2{minus}}, HPO{sub 4}{sup 2{minus}}, and P{sub 2}Mo{sub 5}O{sub 23}{sup 6{minus}} anions. Powder XRD measurements showed that pure molybdenum phosphide had formed after precipitation and reduction with H{sub 2}. MoP crystallizes in the tungsten carbide structure in which each Mo atom is trigonal-prismatically coordinated by six P atoms. The molybdenum phosphide was tested for catalytic activity in the HDN reaction of o-propylaniline at 643 K and 3.0 MPa. The intrinsic HDN activity of the surface Mo atoms of MoP was about 6 times higher than that of Mo edge atoms in {gamma}-Al{sub 2}O{sub 3}-supported MoS{sub 2}. Their selectivity is comparable to that of an Ni-promoted MoS{sub 2} catalyst.

• Research Organization: Swiss Federal Inst. of Tech., Zurich (CH)
• OSTI ID: 20030525
• Journal Information: Journal of Catalysis, Journal Name: Journal of Catalysis Journal Issue: 2 Vol. 191; ISSN 0021-9517; ISSN JCTLA5
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
02 PETROLEUM
03 NATURAL GAS
CATALYTIC EFFECTS
CHEMICAL PREPARATION
CRYSTAL STRUCTURE
DENITRIFICATION
FUELS
HYDROGENATION
MOLYBDENUM PHOSPHIDES