A method for carrying out catalytic gas phase reactions including providing a tube bundle reactor which has a bundle of reaction tubes that are filled with a catalyst charge and are cooled by a heat transfer medium, conveying a reaction gas through the catalyst charge, the reaction gas flowing into each reaction tube divided into two part flows introduced in the axial direction of the reaction tube at different points in the catalyst charge the catalyst charge has at least two catalyst layers of different activity, wherein the activity of the first catalyst layer, in the flow direction of the reaction gas, is lower than the activity of the at least one other catalyst layer and in step a first part flow is introduced into the first catalyst layer and each further part flow is introduced past the first catalyst layer into the at least one further catalyst layer.

A steam reformer is provided which comprises at least one externally-heated tube. Each tube comprises a first catalyst bed comprising a first catalyst in particulate form and a second catalyst supported on a structure, wherein said first catalyst bed is located between the inlet of the tube and the second catalyst supported on said structure. A process for steam reforming of a feed gas mixture using said steam reformer is also provided.

A support structure for a structured catalytic packing is disclosed. The support structure is in a fixed position relative to the reactor tube containing it. It supports catalyzed casings that are free to move relative to the support structure. The support structure and casings are inserted in the reactor tube such that the support structure is located proximate the longitudinal axis of the tube and the casings are located between the support structure and the reactor tube wall. The support structure comprises a central support tube or rod proximate to, and impervious or perforated discs perpendicular to, the longitudinal axis of the reactor tube, and may comprise spacers separating the discs.

A method for revamping a catalytic converter wherein: said catalytic converter comprises a pressure vessel and a catalytic cartridge containing at least one catalyst bed, the pressure vessel includes a cylindrical shell with a full aperture and includes a removable cover of said aperture, and the catalytic cartridge is removable through said upper aperture, and the method includes: installing an additional shell over the aperture of the original shell, thus obtaining an axially extended shell of the pressure vessel; providing an axially extended catalytic cartridge having an axially extended room for holding catalyst in the so obtained axially extended shell.

A reactor having a shell comprising one or more reactor tubes located within the shell, said reactor tube or tubes comprising a plurality of catalyst receptacles containing catalyst; means for providing a heat transfer fluid to the reactor shell such that the heat transfer fluid contacts the tube or tubes; an inlet for providing reactants to the reactor tubes; and an outlet for recovering products from the reactor tubes; wherein the plurality of catalyst receptacles containing catalyst within a tube comprises catalyst receptacles containing catalyst of at least two configurations.

A process for steam or dry reforming of hydrocarbons in a reforming reactor, comprising the steps of: (a) passing a feedstock, comprising one or more hydrocarbons together with steam and/or CO.sub.2, through a first catalytic zone at an elevated temperature, to form a partly reformed process gas, wherein the first catalytic zone comprises one or more elongate conduits, each containing reforming catalyst; and (b) passing the partly reformed process gas through a second catalytic zone at an elevated temperature, so as to form a reformed gas stream, wherein the second catalytic zone comprises one or more elongate conduits, each containing reforming catalyst; wherein the process further comprises the combustion of a fluid fuel with a combustion-sustaining medium in an exothermic combustion region, to form a hot combustion products stream, wherein the exothermic combustion region is adjacent to and laterally surrounds each of the second catalytic zone elongate conduits.

A method for carrying out catalytic gas phase reactions including providing a tube bundle reactor which has a bundle of reaction tubes that are filled with a catalyst charge and are cooled by a heat transfer medium, conveying a reaction gas through the catalyst charge, the reaction gas flowing into each reaction tube divided into two part flows introduced in the axial direction of the reaction tube at different points in the catalyst charge the catalyst charge has at least two catalyst layers of different activity, wherein the activity of the first catalyst layer, in the flow direction of the reaction gas, is lower than the activity of the at least one other catalyst layer and in step a first part flow is introduced into the first catalyst layer and each further part flow is introduced past the first catalyst layer into the at least one further catalyst layer.

A method and reactor for performing exothermic reactions with parallel operated catalyst modules arranged in stacked order within a pressure shell and adapted to axial flow of process gas through one or more catalyst layers and at least one catalyst layer cooled by an intrabed heat exchanger.

A method of testing a catalyst in a reactor comprises supplying a feedstock into an upstream end of the reactor and arranging an annular basket within the reactor at a downstream position in the reactor, the annular basket having a central aperture for receiving the flow of feedstock and plurality of stacked layers separated by fluid permeable material, the plurality of stacked layers including a layer of grading material positioned upstream of a layer containing a primary catalyst to be tested for a chemical process. The grading material is adapted to filter out contaminants within the feedstock and to thereby protect the primary catalyst within the basket. Embodiments and methods can utilize layers comprising a first layer containing the primary catalyst, a second layer containing a hydrometallization catalyst and a third layer containing grading material having solid trap particles with reduced catalytic activity.

A support structure for a structured catalytic packing is disclosed. The support structure is in a fixed position relative to the reactor tube containing it. It supports catalyzed casings that are free to move relative to the support structure. The support structure and casings are inserted in the reactor tube such that the support structure is located proximate the longitudinal axis of the tube and the casings are located between the support structure and the reactor tube wall. The support structure comprises a central support tube or rod proximate to, and impervious or perforated discs perpendicular to, the longitudinal axis of the reactor tube, and may comprise spacers separating the discs.