Supported molybdenum and tungsten carbides were synthesized by temperature-
programmed reactions. These materials were characterized by XRD, EDS analys
is, HRTEM and CO chemisorption. Hydrogenation of tetralin was carried out a
t a total pressure of 4 MPa (3.06 MPa of H-2), at 573 K, without or with su
lfur (200 ppm of sulfur as DMDS). The resulting activities were compared wi
th those of MoS2/Al2O3 and Pt (1% (w/w) metal loading) supported on Al2O3 o
r SiO2 In the absence of sulfur, WC/Al2O3 showed an initial activity simila
r to that of Pt/SiO2, higher than mat of MoS2/Al2O3 but lower than that of
Pt/Al2O3. In the presence of H2S, WC/Al2O3 showed a steady-state activity s
imilar to that of Pt/Al2O3 (which suffered a marked deactivation). Post-rea
ction characterization did not show any sulfur poisoning of the supported c
arbides. Therefore the supported carbides are sulfur-tolerant and promising
catalysts for the hydrogenation of aromatics in diesel fuels in the presen
ce of small amounts of S-containing compounds. (C) 2001 Elsevier Science B.
V. All rights reserved.