Catalytic wall reactors and use of catalytic wall reactors for methane coupling and hydrocarbon cracking reactions

A process to make olefins which comprises the steps of:

• (A) providing a cross-flow chemical reactor fox combined coupling of methane using an oxygen-affording gas and dehydrogenating of saturated hydrocarbon compounds in separated reaction spaces, which reactor comprises;
• a vessel having an entrance port, an exit port, and a passageway therebetween containing a stream of one or more gases flowing from the entrance port to the exit port operable to define a direction of stream flow, and
• passageway therebetween containing a stream of one or more gases flowing from the entrance port to the exit port operable to define a direction of stream flow, and
• at least one reactor core positioned within the vessel comprising an array of tubes having an outer surface including a generally flat entrance surface and a generally flat exit surface spaced apart from and substantially parallel to the entrance surface, and a plurality of tube channels therebetween containing one or more gases flowing from the entrance surface to the exit surface operable to define a direction of channel flow, wherein each channel has a catalytic heat-transfer wall disposed between the channel and a portion of the outer surface of the tubes contacting the gas stream in the passageway, the catalytic heat-transfer wall comprising a ceramic antifoulant coating, a gas-impervious material comprising a high temperature metal or metallic alloy, and, on the portion of the outer surface of the tubes contacting the gas stream in the passageway, a suitable catalyst means for oxidative coupling of methane into higher hydrocarbons, the reactor core further comprising an entrance manifold means in flow communication with channels at the entrance surface of at least one array and an exit manifold means in flow communication with the same channels at one or more exit surface and thereby in flow communication with entrance manifold means, and
• wherein the entrance port, the passageways, the outer surfaces of the tubes, and the exit port form a first zone for introducing and reacting at least one compound therein, and expelling a first gas or gas mixture and wherein the entrance manifold means, the tube channels and the exit manifold means form a second zone within the dual-flow chemical reactor for introducing, reacting at least one compound therein, and expelling a first gas or gas mixture and wherein the entrance manifold means, the tube channels and the exit manifold means form a second zone within the dual-flow chemical reactor for introducing, reacting at least one compound therein, and expelling a second gas or gas mixture;
• (B) introducing a first feed stream which is essentially methane and an oxygen-affording gas into the first zone, coupling the first feed to produce a product containing C.sub.2 hydrocarbons and effectively transferring heat evolved by coupling through the catalytic heat-transfer wall into the second zone, and expelling a residue of the first feed stream,
• (C) introducing a second feed stream which contains predominantly saturated hydrocarbons into the second zone, cracking at least one of the saturated hydrocarbons using heat evolved by coupling from the first zone to provide a majority of the heat required by the cracking to form primarily an olefin-containing product, and expelling a product-containing gas mixture,
• (D) combining the C.sub.2 + containing portions of the effluents from the first zone and the second zone and individually separating the methane and at least the ethylene and propylene olefinic hydrocarbon components thereof, and
• (E) returning unreacted methane contained in the effluent of the first zone together with methane contained in the effluent of the second zone to the first feed stream.