Conversion of a lower alkane

Claim 1

A method for converting at least one feedstock alkane containing from one to three carbon atoms to a more valuable, higher molecular weight hydrocarbon, comprising: (a) passing a reaction mixture comprising the feedstock alkane and air at a pressure in the range of from about 1 to about 50 pounds per square inch gauge through an elongated first reactor packed with a bed of refractory particles, wherein the particles are at a substantially higher temperature than is the incoming reaction mixture and wherein: (1) in the upstream zone of the first reactor, the reaction mixture is contacted with the relatively hotter particles therein, the temperature of which particles increases in the direction of gas flow, whereby the reaction mixture is heated to a temperature at which the reaction of the feedstock alkane with oxygen to form synthesis gas commences, and the particles therein are cooled by contact with the relatively cooler reaction mixture; (2) in the middle zone of the first reactor, the feedstock alkane and oxygen react exothermally to form a gaseous product stream comprising carbon monoxide, hydrogen, and nitrogen and to generate sufficient heat that the temperature of the product stream therein is raised; and (3) in the downstream zone of the first reactor, the product stream is contacted with the relatively cooler particles therein, the temperature of which particles decreases in the direction of gas flow, whereby the product stream is cooled to, and exits the first reactor at, a temperature in the range of from about 100° C. to about 500° C. and whereby the particles therein are heated; and (b) passing the gaseous product mixture stream from the first reactor through an elongated second reactor packed with a bed of particles comprising a Fischer-Tropsch catalyst, maintained at a pressure in the range of from about 1 to about 50 pounds per square inch gauge and cooled to maintain the temperature therein in the range of from about 160° C. to about 240° C., to thereby form a gaseous product stream comprising aliphatic hydrocarbon products having higher molecular weights than the feedstock alkane.

Claim 2

A method for converting at least one feedstock alkane containing from one to three carbon atoms to a more valuable, higher molecular weight hydrocarbon, comprising: (a) passing a reaction mixture comprising the feedstock alkane and air at a pressure in the range of from about 1 to about 50 pounds per square inch gauge through an elongated first reactor packed with a bed of refractory particles, wherein the particles are at a substantially higher temperature than is the incoming reaction mixture and wherein: (1) in the upstream zone of the first reactor, the reaction mixture is contacted with the relatively hotter particles therein, the temperature of which particles increases in the direction of gas flow, whereby the reaction mixture is heated to a temperature at which the reaction of the feedstock alkane with oxygen to form synthesis gas commences, and the particles therein are cooled by contact with the relatively cooler reaction mixture; (2) in the middle zone of the first reactor, the feedstock alkane and oxygen react exothermally to form a gaseous product stream comprising carbon monoxide, hydrogen, and nitrogen and to generate sufficient heat that the temperature of the product stream therein is raised; and (3) in the downstream zone of the first reactor, the product stream is contacted with the relatively cooler particles therein, the temperature of which particles decreases in the direction of gas flow, whereby the product stream is cooled to, and exits the first reactor at, a temperature in the range of from about 100° C. to about 500° C. and whereby the particles therein are heated; and (b) passing the gaseous product mixture stream from the first reactor through an elongated second reactor packed with a bed of particles comprising a Fischer-Tropsch catalyst, maintained at a pressure in the range of from about 1 to about 50 pounds per square inch gauge and cooled to maintain the temperature therein in the range of from about 160° C. to about 240° C., to thereby form a gaseous product stream comprising aliphatic hydrocarbon products having higher molecular weights than the feedstock alkane.

Claim 34

The method of cClaim 32 wherein the Fischer-Tropsch catalyst additionally comprises at least one of a magnesium-containing component, a thorium-containing component, a tin-containing component, a manganese-containing component, or a zirconium-containing component.