Methods, reactor tubes, reactors, and systems for catalysis are disclosed. A reactor tube includes an outer shell defining a catalyst bed, a catalyst within the catalyst bed, and an inner tube extending through the catalyst bed. An interior of the inner tube is isolated from the catalyst within the catalyst bed. Methods of activating a catalyst are also disclosed herein.

Methods, reactor tubes, reactors, and systems for catalysis are disclosed. A reactor tube includes an outer shell defining a catalyst bed, a catalyst within the catalyst bed, and an inner tube extending through the catalyst bed. An interior of the inner tube is isolated from the catalyst within the catalyst bed. Methods of activating a catalyst are also disclosed herein.

One object of the present invention is to provide a method for producing stable isotope labeled carbon monoxide capable of controlling the abundance ratio of a specific kind of the stable oxygen isotope to be an arbitrary value, the present invention provides a method for producing stable isotope labeled carbon monoxide including: a first mixing step in which carbon monoxide selectively containing at least one kind of stable isotope selected from the group consisting of .sup.12C.sup.16O, .sup.12C.sup.17O, .sup.12C.sup.18O, .sup.13C.sup.16O, .sup.13C.sup.17O, and .sup.13C.sup.18O, and water vapor selectively containing at least one kind of stable isotope selected form the group consisting of H.sub.2.sup.16O, H.sub.2.sup.17O and H.sub.2.sup.18O are mixed to produce stable isotope labeled carbon dioxide: and a second mixing step in which the stable isotope labeled carbon dioxide produced in the first mixing step and hydrogen are mixed.

One object of the present invention is to provide a method for producing stable isotope labeled carbon monoxide capable of controlling the abundance ratio of a specific kind of the stable oxygen isotope to be an arbitrary value, the present invention provides a method for producing stable isotope labeled carbon monoxide including: a first mixing step in which carbon monoxide selectively containing at least one kind of stable isotope selected from the group consisting of .sup.12C.sup.16O, .sup.12C.sup.17O, .sup.12C.sup.18O, .sup.13C.sup.16O, .sup.13C.sup.17O, and .sup.13C.sup.18O, and water vapor selectively containing at least one kind of stable isotope selected form the group consisting of H.sub.2.sup.16O, H.sub.2.sup.17O and H.sub.2.sup.18O are mixed to produce stable isotope labeled carbon dioxide: and a second mixing step in which the stable isotope labeled carbon dioxide produced in the first mixing step and hydrogen are mixed.

Reactors are provided that can include a first set of fluid channels and a second set of fluid channels oriented in thermal contact with the first set of fluid channels where the channels of either one or both of the first of the set of fluid channels are non-linear. Reactor assemblies are also provided that can include a first set of fluid channels defining at least one non-linear channel having a positive function, and a second set of fluid channels defining at least another non-linear channel having a negative function in relation to the positive function of the one non-linear channel of the first set of fluid channels.

Reactors are provided that can include a first set of fluid channels and a second set of fluid channels oriented in thermal contact with the first set of fluid channels where the channels of either one or both of the first of the set of fluid channels are non-linear. Reactor assemblies are also provided that can include a first set of fluid channels defining at least one non-linear channel having a positive function, and a second set of fluid channels defining at least another non-linear channel having a negative function in relation to the positive function of the one non-linear channel of the first set of fluid channels.

Described herein is a gaslight multilayered composite tube having a heat transfer coefficient of >500 W/m.sup.2/K which in its construction over the cross section of the wall of the composite tube includes as an inner layer a nonporous monolithic oxide ceramic surrounded by an outer layer of oxidic fiber composite ceramic, where this outer layer has an open porosity of 5%<ε<50%, and which on the inner surface of the composite tube includes a plurality of depressions oriented towards the outer wall of the composite tube. Also described herein is a method of using the multilayered composite tube as a reaction tube for endothermic reactions, jet tubes, flame tubes or rotary tubes.

Described herein is a gaslight multilayered composite tube having a heat transfer coefficient of >500 W/m.sup.2/K which in its construction over the cross section of the wall of the composite tube includes as an inner layer a nonporous monolithic oxide ceramic surrounded by an outer layer of oxidic fiber composite ceramic, where this outer layer has an open porosity of 5%<ε<50%, and which on the inner surface of the composite tube includes a plurality of depressions oriented towards the outer wall of the composite tube. Also described herein is a method of using the multilayered composite tube as a reaction tube for endothermic reactions, jet tubes, flame tubes or rotary tubes.

A catalyst suitable for use in carbon oxide conversion reactions is described, said catalyst in the form of a shaped unit formed from an oxidic catalyst powder, said catalyst comprising 30-70% by weight of copper oxide, combined with zinc oxide, alumina and silica, having a Si:AI atomic ratio in the range 0.005 to 0.15:1, and having a BET surface area >105 m.sup.2/g and a copper surface area >37 m.sup.2/g catalyst. The catalyst is prepared by a co-precipitation method using an alumina sol.

A catalyst suitable for use in carbon oxide conversion reactions is described, said catalyst in the form of a shaped unit formed from an oxidic catalyst powder, said catalyst comprising 30-70% by weight of copper oxide, combined with zinc oxide, alumina and silica, having a Si:AI atomic ratio in the range 0.005 to 0.15:1, and having a BET surface area >105 m.sup.2/g and a copper surface area >37 m.sup.2/g catalyst. The catalyst is prepared by a co-precipitation method using an alumina sol.