Low temperature pathways to Chevrel phases via reduced molybdenum sulfide cluster complexes
The initial cluster compound, Na{sub 2y}Mo{sub 6}S{sub 8+y} (py){sub x}, was discovered by reacting Mo{sub 6}Cl{sub 12} with higher stoichiometries of sodium hydrosulfide and sodium butoxide in butanol/pyridine. This compound can subsequently undergo ligand exchange reactions to form a variety of cluster complexes. Single-crystal structure determinations are reported for the pyridine (py), piperidine (pip), and pyrrolidine (pyrr) complexes: triclinic Mo{sub 6}S{sub 8}(PY){sub 6}{center_dot}1.65py, cubic Mo{sub 6}S{sub 8}(py){sub 6}{center_dot}2py, Mo{sub 6}S{sub 8}(pip){sub 6}{center_dot}7pip, and Mo{sub 6}S{sub 8}(pyrr){sub 6}{center_dot}1pyrr. Delegation of the cluster complexes was explored. Direct heating under dynamic vacuum led to incomplete deligation. Reactions with tin and lead resulted in formation of corresponding Chevrel phase compounds along with MoS{sub 2}. Thermolysis reactions in the presence of flowing ammonia gas resulted in further delegation than was evidenced for reactions explored in vacuo. Solution reactions with strong acids were studied in an attempt to protonate the ligands and thus make them better leaving groups only limited success was achieved. A new preparative route was developed for ternary molybdenum sulfides. Cation exchange reactions with Na{sub 2y}Mo{sub 6}S{sub 8+y}(MeOH){sub x} were used to form the cobalt, tin, lead, and holmium compounds. Preliminary hydrodesulfurization studies on the sodium and cobalt compounds showed that they possess larger surface areas and thiophene conversion percentages than Chevrel phases, but a lower HDS rate.
- Research Organization:
- Ames Lab., IA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-82
- OSTI ID:
- 10154971
- Report Number(s):
- IS-T-1609; ON: DE93013282
- Resource Relation:
- Other Information: TH: Thesis (Ph.D.); PBD: 30 Mar 1993
- Country of Publication:
- United States
- Language:
- English
Similar Records
Synthesis, structure, and characterization of n-ligated Mo[sub 6]S[sub 8]L[sub 6] cluster complexes. Molecular precursors to Chevrel phases
High-yield synthesis of the W{sub 6}S{sub 8} cluster unit as the pyridine complex (W{sub 6}S{sub 8})(py){sub 6} and attempts to prepare tungsten analogues of the Chevrel phases
Related Subjects
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
02 PETROLEUM
MOLYBDENUM SULFIDES
COMPLEXES
DESULFURIZATION
CATALYSTS
HETEROGENEOUS CATALYSIS
MOLECULAR CLUSTERS
CRYSTAL STRUCTURE
PIPERIDINES
PYRIDINE
PYRROLIDINES
LIGANDS
POLYCYCLIC SULFUR HETEROCYCLES
360601
400201
020400
PREPARATION AND MANUFACTURE
CHEMICAL AND PHYSICOCHEMICAL PROPERTIES
PROCESSING