Conversion of alcohols to distillate fuels

Abstract

A process for the production of jet and other heavy fuels from alcohols and mixture of alcohols is disclosed. The process may include contacting in a reaction zone at least one C2 to C11 alcohol with a solid catalyst having activity for the simultaneous dehydration of the alcohols to form olefins, isomerization of the olefins to form internal olefins, and oligomerization of the olefins produced in situ via the dehydration reaction to form an effluent comprising mono-olefinic hydrocarbons. Preferably, the alcohol feed is a mixture of alcohols, such as C2 to C7 alcohols or C4 and C6 alcohols, enabling the production of a mixture of branched hydrocarbons that may be used directly as a jet fuel without blending.

What is claimed: 
     
         1 . A process for the production of distillate fuels, the process comprising:
 contacting, in a reaction zone, a light olefin feedstock, comprising one or more C8-C12 olefins, and an alcohol feedstock, comprising a C4 alcohol selected from the group consisting of 2-butanol, 1-butanol, and isobutanol or mixtures thereof, with a solid acid catalyst at conditions of temperature and pressure where the solid acid catalyst has activity for the simultaneous:
 i. dehydration of the C4 alcohol to form water and C4 olefins, 
 ii. oligomerization of the olefins produced in situ, 
 iii. positional isomerization of the C4 olefins, C8-C12 olefins, and olefin oligomers to form internal olefins, and 
 iv. reaction of the C8-C12 olefins with the olefins produced in situ, 
 to form an effluent comprising branched mono-olefinic distillate fuel range hydrocarbon oligomers; 
   separating the branched mono-olefinic distillate fuel range hydrocarbon oligomers from water and any unreacted alcohol;   fractionating the branched mono-olefinic distillate fuel range hydrocarbon oligomers to recover the light olefin feedstock and a heavy oligomer fraction.   
     
     
         2 . The process of  claim 1 , wherein the light olefin feedstock comprises C8 and lighter olefins. 
     
     
         3 . The process of  claim 1 , wherein the light olefin feedstock comprises C10 and lighter olefins. 
     
     
         4 . The process of  claim 1 , wherein the light olefin feedstock comprises C12 and lighter olefins. 
     
     
         5 . The process of  claim 1 , wherein a yield of jet fuel range hydrocarbons is at least 75 wt %, based on the alcohol feedstock, of the theoretical maximum jet range olefin yield. 
     
     
         6 . The process of  claim 1 , further comprising recycling the unreacted alcohols to the reaction zone. 
     
     
         7 . The process of  claim 1 , further comprising hydrogenating the heavy fraction to produce a paraffinic hydrocarbon product. 
     
     
         8 . The process of  claim 7 , further comprising fractionating the paraffinic hydrocarbon product into one or more hydrocarbon fractions useful as a fuel or a fuel blendstock. 
     
     
         9 . The process of  claim 8 , wherein the one or more hydrocarbon fractions are suitable for use as a fuel grade product, without blending with petroleum-derived fuels. 
     
     
         10 . The process of  claim 1 , wherein the alcohol mixture comprises at least one secondary alcohol selected from the group consisting of 2-butanol, 2-pentanol, 2-hexanol, and combinations thereof. 
     
     
         11 . The process of  claim 1 , wherein the alcohols feedstock comprises 2-butanol. 
     
     
         12 . The process of  claim 1 , wherein the alcohol feedstock comprises isobutanol. 
     
     
         13 . The process of  claim 1 , wherein the alcohol feedstock comprises 1-butanol. 
     
     
         14 . The process of  claim 1 , wherein the alcohol feedstock comprises water and bio-derived 2-butanol. 
     
     
         15 . A process for the production of distillate fuels, the process comprising:
 feeding a C8-C10 olefin and an alcohol feedstock, comprising isobutanol or a mixture of alcohols comprising isobutanol, in a reactor comprising a first reaction zone and a second reaction zone,
 the first reaction zone comprising a first catalyst bed containing a solid acid catalyst having activity at conditions in the first reaction zone for the simultaneous dehydration of alcohols to form olefins and water, positional isomerization of olefins to form internal olefins, oligomerization of the olefins, and reaction of the olefins with the C8-C10 olefin, to form a mono-olefinic hydrocarbon product, and 
 the second reaction zone comprising a second catalyst bed containing a water-tolerant catalyst having activity for the hydrogenation of the mono-olefinic hydrocarbon product to form an effluent comprising paraffinic hydrocarbons, including the distillate fuel range hydrocarbons. 
   
     
     
         16 . The process of  claim 15 , further comprising separating the paraffinic hydrocarbons from unreacted alcohols. 
     
     
         17 . The process of  claim 15 , further comprising fractionating the paraffinic hydrocarbons into one or more hydrocarbon fractions useful as a fuel or a fuel blendstock. 
     
     
         18 . The process of  claim 15 , wherein the alcohol feedstock comprises 2-butanol and/or 2-hexanol. 
     
     
         19 . The process of  claim 15 , wherein the C8-C10 olefin comprises a C8 olefin. 
     
     
         20 . The process of  claim 15 , wherein the C8-C10 olefin comprises a C10 olefin.