Organo-Al-chloride catalyzed poly-n-butenes process
AssigneeExxon Chemical Patents Inc.
InventorFrank J. Chen
Life of this patent
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Abstract
Poly-n-butene is prepared from a mixed C.sub.4 hydrocarbon feedstream containing less than about 5 wt. % isobutylene using an organo-aluminum chloride-HCl catalyst system wherein the HCl is introduced separately into the feedstream to form organochloride in the feedstream. Polymer product having a very narrow molecular weight distribution is obtained over the M.sub.n range of 300 to 900. Detergents derived from this poly-n-butene exhibit substantially improved performance in lubricating oil compositions.
Claims39
A process for preparing low molecular weight poly-n-butene having an M.sub.n in the range of about 300 to about 900 and a molecular weight distribution less than about 1.4 from a feedstream mixture of C.sub.4 hydrocarbons containing less than about 5% by weight isobutylene and containing at least about 12 wt.% normal-butenes in a stirred reaction zone maintained at a temperature of less than about 90.C, which comprises:
- (a) injecting HCl in an amount of from about 0.005 to 0.6 parts by weight per 100 parts by weight of said feedstream mixture into said feedstream mixture, in the substantial absence of said organo-aluminum catalyst and under conditions sufficient to substantially completely react said injected HCl with normal-butenes, thereby producing a treated feedstream mixture which contains less than 1.0 ppm free HCl;
- (b) simultaneously introducing said treated feedstream mixture and said organo-aluminum chloride catalyst as separate streams into said reaction zone;
- (c) contacting said introduced treated feedstream mixture and said introduced catalyst in the reaction zone for a time and under conditions sufficient to form a polymerization reaction mixture containing said poly-n-butene;
- (d) withdrawing said polymerization reaction mixture from said reaction zone;
- and
- (e) recovering said poly-n-butene product from said withdrawn polymerization reaction mixture.
The process of claim wherein the organo-aluminum chloride is added in admixture with C.sub.4 hydrocarbons.
A continuous process for preparing low molecular weight poly-n-butene having an M.sub.n in the range of about 300 to about 900 and a molecular weight distribution less than about 1.4 from a feedstream mixture of C.sub.4 hydrocarbons containing less than about 5% by weight isobutylene and containing at least about 12 wt.% normal-butenes in a stirred reaction zone maintained at a temperature of about 5.degree. C. to 80.degree. C., which comprises:
- (a) injecting HCl in an amount of from about 0.005 to 0.6 parts by weight per 100 parts by weight of said feedstream mixture into said feedstream mixture, in the substantial absence of said organo-aluminum catalyst and under conditions sufficient to substantially completely react said injected HCl with normal-butenes, thereby producing a treated feedstream mixture which contains less than 1.0 ppm free HCl;
- (b) simultaneously continuously introducing said treated feedstream mixture and said organo-aluminum chloride catalyst as separate streams into said reaction zone;
- (c) contacting said introduced treated feedstream mixture and said introduced catalyst in the reaction zone for a time and under conditions sufficient to form a polymerization reaction mixture containing said poly-n-butene;
- (d) continuously withdrawing said polymerization reaction mixture from said reaction zone;
- and
- (e) recovering said poly-n-butene product from said withdrawn polymerization reaction mixture.
Dependencies are inferred from the claim text.