Hydrocarbon synthesis

Abstract

A method of synthesizing hydrocarbons from smaller hydrocarbons includes the steps of hydrocarbon halogenation, simultaneous oligomerization and hydrogen halide neutralization, and product recovery, with a metal-oxygen cataloreactant used to facilitate carbon-carbon coupling. Treatment with air or oxygen liberates halogen and regenerates the cataloreactant.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) [0001] This application claims the benefit of U.S. Provisional Patent Application No. 60 / 487,364, filed Jul. 15, 2003.FIELD OF THE INVENTION [0002] This invention relates generally to hydrocarbon oligomerization, and more particularly to a method of making hydrocarbons using cataloreactants. BACKGROUND OF THE INVENTION [0003] Scientists have long sought efficient ways to convert methane and other alkanes into higher hydrocarbons, including light olefins and gasoline-range materials. Efficient processes could create value in a number of ways, including: facilitating the utilization of remotely located stranded natural gas through its conversion into more easily transportable liquid fuels and feedstocks, and allowing the use of inexpensive feedstocks (methane and other lower alkanes) for end products often made from higher alkanes, including ethylene and propylene. [0004] U.S. Pat. Nos. 6,486,368, 6,472,572, 6,465,699, 6,465,696, and 6,462,243...

AI Technical Summary

Benefits of technology

[0011] The present invention addresses the need for an efficient way to convert methane and other hydrocarbons into higher hydrocarbons. In one embodiment, a hydrocarbon having a carbon number Cn, where n≧2, is prepared by allowing a reactant hydrocarbon having a carbon number Cm, where m<n, to react with a halogenating agent, thereby forming a halogenated hydrocarbon; allowing the halogenated hydrocarbon to contact a metal-oxygen cataloreactant, thereby forming a product hydrocarbon having an carbon number Cn, where n≧2; recovering the product hydrocarbon; and regenerating the cataloreactant. Often, a mixture of hydrocarbons is obtained, but careful selection of the reactant hydrocarbon, halogenating agent, metal-oxygen cataloreactant, and reaction conditions allow a tailored approach to hydrocarbon product formation. Methane (i.e., natural gas) as well as other light hydrocarbons, e.g., C2 to C6 hydrocarbons, are envisioned as preferred feedstocks.

Problems solved by technology

The light hydrocarbons can be recycled for further processing over the oxyhydrochlorination catalyst.” All of these techniques for making higher alkanes from C1 feedstocks suffer from the disadvantage that the hydrocarbon stream must be separated from an aqueous hydrohalic acid stream, and the hydrohalic acid stream must be recycled.

The process does not incorporate reactive neutralization of hydrogen halide, and appears to suffer from slow kinetics.

Liquid phase chemistry, however, typically suffers from such disadvantages as the requirement of solvent, corrosion, and lower rates of reaction than gas-phase chemistry.

In addition, such a process consumes energy required to produce the magnesium metal needed for the energetic and reducing Grignard reagents.