Processes for converting c2-c5 hydrocarbons to gasoline and diesel fuel blendstocks

Abstract

Methods for the thermal olefination of a methane feedstream involving the thermal cracking of the methane feedstream at selected temperatures and pressures in the absence of a catalyst, steam or added oxygen. The methane feedstream contains greater than 85 wt % methane, and the thermal cracking produces an effluent stream containing greater than 20 wt % ethylene. Thermal cracking is optionally performed at less than 1,100° C., and in some embodiments at 850-900° C. The methane feedstream optionally contains greater than 95 wt % methane and produces an effluent stream containing greater than 30 wt % olefins. Methane in the effluent stream may be recycled to the methane feedstream.

1 . (canceled) 
     
     
         2 . A method for methane thermal olefination comprising thermal cracking a methane feedstream comprising more than 85 wt % methane at a temperature of less than 1,100° C. and a pressure of at most 150 psig, the thermal cracking being performed without a catalyst and without steam to yield an effluent stream containing greater than 20 wt % ethylene. 
     
     
         3 . The method of  claim 2  in which methane in the effluent stream is recycled to the feedstream for the thermal cracking. 
     
     
         4 . The method of  claim 2  in which the thermal cracking is performed without added oxygen. 
     
     
         5 . The method of  claim 2  in which the methane feedstream comprises more than 95 wt % methane feedstream and the effluent stream contains greater than 30 wt % olefins. 
     
     
         6 . The method of  claim 2  in which the thermal cracking is performed at 850-900° C. 
     
     
         7 . The method of  claim 2  in which the effluent stream is passed through a hydrogen separator to separate the ethylene from hydrogen and methane in the effluent stream. 
     
     
         8 . The method of  claim 7  in which the separated methane is recycled to the feedstream for the thermal cracking. 
     
     
         9 . The method of  claim 2  in which the thermal cracking is performed at 50° C. and 1 atmosphere pressure yielding an effluent stream comprising hydrogen, methane, benzene and acetylene. 
     
     
         10 . The method of  claim 2  in which alumina is provided during thermal cracking to remove carbon.