Description of coordinatively unsaturated sites regeneration over MoS2-based HDS catalysts using 35S experiments combined with computer simulations
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access URL: https://hal.science/hal-00098365
format: HTML
issued: 2026-05-05T13:07:24.705241
modified: 2026-05-05T13:07:24.665283

Description of coordinatively unsaturated sites regeneration over MoS2-based HDS catalysts using 35S experiments combined with computer simulations
type: Dataset
contact point: Organization
  fn: CCSD
keyword: infoeu-reposemanticsarticle
keyword: mos2
keyword: 35s-tracer-experiments
keyword: nimos
keyword: hds
keyword: journal-articles
keyword: chimcatachemical-sciencescatalysis
keyword: computer-simulations
keyword: dbt
keyword: comos
keyword: activation-energy
keyword: h2s-liberation
landing page: 0926-860X
description: By combining experimental results and computer simulations, we previously showed that the coordinatively unsaturated sites (CUS) formation over MoS2 is most likely to occur on the MoS2 metallic edge through the departure of an H2S molecule. In the present paper, we aimed at examining the H2S departure from MoS2 catalysts promoted with Co and Ni. The [35S]DBT HDS experiments results showed that over CoMoS/Al2O3 and NiMoS/Al2O3 catalysts, the activation energy of the H2S release reaction is essentially the same with respective values of 7.4 kcal.mol-1 and 7.9 kcal.mol-1. Considering the H2S departure activation energy in the case of the non-promoted MoS2 surface (10 ~ 12 kcal.mol-1), this result illustrates the synergetic effect between Mo and Co or Ni in terms of CUS regeneration easiness. Further, preliminary computer simulations results showed that for S atoms bridged between Co atoms, a mechanism implying H2S departure from the metallic edge cannot be reasonably envisaged. Moreover, on the sulfur edge the H2S release activation energy is too high (~ 13.5 kcal.mol-1) if we consider experimental results on CoMo/Al2O3 catalysts but not incompatible with the experimental value obtained over Co/Al2O3 catalysts (ca. 10 kcal.mol-1), which suggests that the mechanism on the promoted catalyst differs from that on the un-promoted one.
issued: 2026-05-05T13:07:24.698356
language: en
modified: 2026-05-05T13:07:24.698362

test_moissonnage_selune
type: Agent