Catalytic reactor and organometallic model studies of the mechanism of thiophene hydrodesulfurization

Technical Report · Mon Jun 01 00:00:00 EDT 1987

OSTI ID:6368442

Sauer, N N

The reactivity of transition metal complexes of thiophene (Th) and 2,3- and 2,5-dihydrothiophenes (DHT) and catalytic reactor studies of thiophene and the dihydrothiophenes have been used to examine the mechanism for the hydrodesulfurization (HDS) of thiophene. Catalytic deuterium exchange of thiophene over HDS catalysts was modeled by the reaction of ..pi..-thiophene complexes, CpRu(Th)/sup +/ (where Th=thiophene, 2, or 3 methylthiophene or 2,5-dimethylthiophene) in CD/sub 3/OD with OH/sup -/. Reactor studies with thiophene and 2,3- and 2,5-DHT were done at 300/sup 0/ and 400/sup 0/C over a Re/..gamma..-Al/sub 2/O/sub 3/ HDS catalyst. Deuterodesulfurization studies established that 2,5-DHT directly eliminates butadiene while butadiene formation from 2,3-DHT must involve several surface steps over the catalyst. Several reactions of the dihydrothiophenes over HDS catalysts were modeled using transition metal complexes of 2,3 and 2,5-DHT. The S-bound 2,3-DHT in W(CO)/sub 5/(2,3-DHT) is converted to tetrohydrothiophene upon treatment with HCl. When Fe/sub 2/(CO)/sub 9/ is reacted in THF with 2,3-DHT though, no isolable Fe(CO)/sub 4/(2,3-DHT) complex is obtained, but small amounts of 2,5-DHT are observed by /sup 1/H NMR. Reaction of 2,5-DHT with Fe/sub 2/(CO)/sub 9/ does result in the formation of Fe(CO)/sub 4/(2,5-DHT), which readily eliminates butadiene.

• Research Organization: Ames Lab., IA (USA)
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6368442
• Report Number(s): IS-T-1289; ON: DE87010924
• Resource Relation: Other Information: Thesis. Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
DESULFURIZATION
CATALYSIS
DEUTERIUM
ISOTOPIC EXCHANGE
THIOPHENE
BUTADIENE
CATALYSTS
CHEMICAL REACTION KINETICS
CYCLOPENTADIENE
RHENIUM COMPLEXES
RUTHENIUM COMPLEXES
TRANSITION ELEMENT COMPLEXES
ALKENES
CHEMICAL REACTIONS
COMPLEXES
CYCLOALKENES
DIENES
HETEROCYCLIC COMPOUNDS
HYDROCARBONS
HYDROGEN ISOTOPES
ISOTOPES
KINETICS
LIGHT NUCLEI
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
POLYENES
REACTION KINETICS
STABLE ISOTOPES
400201* - Chemical & Physicochemical Properties
400202 - Isotope Effects
Isotope Exchange
& Isotope Separation