Date of Award

2015-01-01

Degree Name

Doctor of Philosophy

Department

Material Science and Engineering

Advisor(s)

RUSSELL R. CHIANELLI

Abstract

Transition state computational studies of the sulfur removal from dibenzothiophene (DBT) molecule have herein been performed considering the Co9S8/MoS2 interface existing on unsupported Co/MoS2 catalysts. The linear synchronous transit (LST) and quadratic synchronous transit (QST) methods integrated in a density functional theory (DFT) program such as Dmol3 were used for the calculations of energy barriers of the transition states. Three different configurations present on the Co9S8/MoS2 interface have been envisaged as possible catalytic sites: sulfur-sulfur (S, S) sites, and molybdenum-sulfur (Mo, S) and molybdenum-molybdenum (Mo, Mo) edge sites. This study revealed that the (Mo, Mo) edge site is the most catalytically active site for the hydrodesulfurization (HDS) reaction followed by the (Mo, S) edge site while the (S, S) site shows almost inertness for the HDS reaction. This information allows us to propose clues to design new catalysts based on bulk Co9S8/MoS2 phases with higher efficiency

by increasing the proportion of (Mo, Mo) edge sites.

Language

en

Provenance

Received from ProQuest

File Size

146 pages

File Format

application/pdf

Rights Holder

Gabriel Angel Gonzalez

Download

Share

COinS