Ethanol to fuels in a catalytic cracking unit stripper

Abstract

Processes relating to the conversion of ethanol in a stripper unit of a fluidized catalytic cracking system. An ethanol stream mixes with a catalyst in the stripper unit under conditions of temperature that favor conversion of the ethanol to hydrocarbons, thereby increasing incorporation of ethanol into liquid transportation fuels without exceeding regulatory limits on fuel vapor pressure. Certain embodiments combine the ethanol stream with a hydrocarbon stream and react in the presence of a catalyst in a stripper to produce hydrocarbons that may have an increased boiling point, increased octane rating, decreased vapor pressure, decreased benzene content, or combinations thereof.

We claim: 
     
         1 . A process for converting ethanol to liquid transportation fuels, the process comprising mixing and reacting a catalyst with an ethanol stream within a stripper unit of a fluidized catalytic cracking unit to produce a mixed product stream comprising hydrocarbons, wherein the ethanol stream comprises water that is converted to steam within the stripper unit. 
     
     
         2 . The process according to  claim 1 , additionally comprising mixing a stream of cracked hydrocarbons, light olefins, or combinations thereof with the ethanol stream to form a mixture, and reacting the mixture with the catalyst in the stripper unit to produce a mixed product stream comprising hydrocarbons. 
     
     
         3 . The process according to  claim 2 , wherein the reacting comprises alkylation, oligomerization, condensation or combinations thereof. 
     
     
         4 . The process according to  claim 2 , wherein the reacting decreases the Reid vapor pressure, the total benzene content, or both, of the mixed product stream. 
     
     
         5 . The process according to  claim 2 , wherein the reacting increases at least one of the molecular weight, the alkylaromatics content and the octane of the mixed product stream. 
     
     
         6 . The process according to  claim 1 , wherein the catalyst is a spent catalyst taken from a fluidized catalytic cracking reaction zone. 
     
     
         7 . The process according to  claim 1 , wherein the steam contacts the catalyst within the stripper unit to at least partially strip hydrocarbons from the catalyst prior to the reacting. 
     
     
         8 . The process according to  claim 1 , wherein the water in the ethanol stream is converted to steam either prior to, or upon entering the stripper unit to prevent contact between the water and the catalyst. 
     
     
         9 . The process according to  claim 8 , wherein the steam produced from the water in the ethanol stream serves as at least a portion of the steam required to at least partially strip hydrocarbons from the catalyst. 
     
     
         10 . The process according to  claim 1 , wherein the ethanol stream is derived from biomass and comprises at least 4 weight percent of water. 
     
     
         11 . A process for converting ethanol that is derived from biomass to liquid transportation fuels, comprising mixing and reacting a catalyst with an ethanol stream and a stream of cracked hydrocarbons comprising aromatics, light olefins, or mixtures thereof within a stripper unit of a fluidized catalytic cracking unit to produce a mixed product stream comprising hydrocarbons, wherein the ethanol stream comprises water that is converted to steam prior to the reacting. 
     
     
         12 . The process according to  claim 11 , wherein the catalyst facilitates the alkylation of the aromatics in the stream of cracked hydrocarbons by the ethanol to produce hydrocarbons possessing an increased octane rating, a lower Reid vapor pressure or combinations thereof. 
     
     
         13 . The process according to  claim 11 , wherein the reacting decreases the content of benzene in the mixed product stream. 
     
     
         14 . The process according to  claim 11 , wherein the stream of cracked hydrocarbons is produced by the fluidized catalytic cracking unit. 
     
     
         15 . The process according to  claim 11 , wherein the stream of cracked hydrocarbons is recycled from a fractionator located immediately downstream from the fluidized catalytic cracking unit. 
     
     
         16 . The process according to  claim 11 , wherein the catalyst is a spent catalyst taken from a fluidized catalytic cracking reaction zone. 
     
     
         17 . The process according to  claim 11 , wherein the steam contacts the catalyst within the stripper unit to at least partially strip hydrocarbons from the catalyst prior to the reacting. 
     
     
         18 . The process according to  claim 11 , wherein the water in the ethanol stream is converted to steam either prior to, or upon entering the stripper unit to prevent contact between the water and the catalyst. 
     
     
         19 . The process according to  claim 18 , wherein the steam produced from the water in the ethanol stream serves as at least a portion of the steam required to at least partially strip hydrocarbons from the catalyst. 
     
     
         20 . The process according to  claim 11 , wherein the ethanol stream comprises at least 4 weight percent water.