Fluorination aerosol

Aerosol Fluorination of Dimethoxymethane, 111 Fluorination with Cesium Fluoroxysulfate... 

The Aerosol Fluorination process [42] (Aerosol) is operated on the principle that the substrate is absorbed onto the surface of fine sodium fluoride particles in the fluorination apparatus in which the fluorine concentration and the temperature increases along the length of the reaction vessel. A U.V. photo-fluorination finishing stage completes the perfluorination process which has the advantage that it is a continuous flow method. 

Detailed studies concerning the perfluorination of haloalkanes by the aerosol fluorination technique have recently been conducted by Adcock and co-workers... 

Although the concentration of fluorine is the most important quantity in the control of the reaction rate and must be maintained within certain limits, in practice the stoichiometry, the molecular fluorine to substrate H-atom molar ratio, is used to determine the reaction parameters leading to a successful and efficient perfluorination. AF is most successful when sublimable solids are introduced into the hydrocarbon evaporator unit of the aerosol fluorinator as solutions by a syringe pump. This now common procedure emphasizes the individual molecule s isolation as it is fluorinated using AF. No intermolecular reactions between solute and solvent have been observed Choice of the solvent is important as it must not boil at a temperature below the melting point of the solute in order to prevent solid deposition in the tubes feeding the evaporator. It must also fluorinate to a material easily separable from the solid reactant after perfluorination. In most cases it has been found that aliphatic hydrochlorocarbons are excellent choices, but that carbon tetrachloride and chloroform and other radical-scavenging solvents are not (sec ref 6). 

Experimental Procedure Aerosol Fluorination of Dimethoxy methane [29]... 

In a related aerosol fluorination technique [122-124], a substrate is absorbed onto fine particles of sodium fluoride which are then sprayed into a stream of dilute fluorine many perfluorinated highly branched and cyclic alkanes have been prepared by this method. 

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