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Title: Synthesis and characterization of Fe colloid catalysts in inverse micelle solutions

Surfactant molecules, possessing a hydrophilic head group and a hydrophobic tail group, aggregate in various solvents to form structured solutions. In two component mixtures of surfactant and organic solvents (e.g., toluene and alkanes), surfactants aggregate to form inverse micelles. Here, the hydrophilic head groups shield themselves by forming a polar core, and the hydrophobic tails groups are free to move about in the surrounding oleic phase. The formation of Fe clusters in inverse miscelles was studied.Iron salts are solubilized within the polar interior of inverse micelles, and the addition of the reducing agent LiBH{sub 4} initiates a chemical reduction to produce monodisperse, nanometer sized Fe based particles. The reaction sequence is sustained by material exchange between inverse micelles. The surfactant interface provides a spatial constraint on the reaction volume, and reactions carried out in these micro-heterogeneous solutions produce colloidal sized particles (10-100{Angstrom}) stabilized in solution against flocculation of surfactant. The clusters were stabilized with respect to size with transmission electron microscopy (TEM) and with respect to chemical composition with Mossbauer spectroscopy, electron diffraction, and x-ray photoelectron spectroscopy (XPS). In addition, these iron based clusters were tested for catalytic activity in a model hydrogenolysis reaction. The hydrogenolysis of naphthyl bibenzyl methanemore » was used as a model for coal pyrolysis.« less
Authors:
; ;  [1]
  1. Sandia National Lab., Alburquerque, NM (United States) [and others
Publication Date:
OSTI Identifier:
198293
Report Number(s):
CONF-9508133--
ON: DE96001664; TRN: 95:008316-0050
DOE Contract Number:
AC04-76DP00789
Resource Type:
Conference
Resource Relation:
Conference: Coal liquefaction and gas conversion contractor review meeting, Pittsburgh, PA (United States), 29-31 Aug 1995; Other Information: PBD: [1995]; Related Information: Is Part Of Coal liquefaction and gas conversion contractors review conference: Proceedings; PB: 733 p.
Research Org:
USDOE Pittsburgh Energy Technology Center, PA (United States)
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; COAL LIQUEFACTION; CATALYSTS; IRON COMPOUNDS; CATALYTIC EFFECTS; MOESSBAUER EFFECT; COLLOIDS; MICELLAR SYSTEMS