Size-reversing materials for reforming in cyclic flow reactors

A method for reforming hydrocarbons in a cyclic reaction environment, comprising:

• reacting a mixture comprising fuel and 0.1 vol % O2 or more under combustion conditions in a combustion zone within a reactor to heat one or more surfaces in a reaction zone to a regenerated surface temperature of 1100° C. or more, the mixture of fuel and O2 comprising 120% or more of a stoichiometric molar amount of O2 for combustion of the fuel, the reaction zone comprising a catalyst system supported on one or more surfaces of a support structure, the catalyst system comprising i) Ni and Al2O3, ii) NiO and Al2O3, iii) NiAl2O4, or iv) a combination of two or more of i), ii) and iii);
• exposing a reactant stream comprising a reformable hydrocarbon to the one or more surfaces in the reaction zone to increase the temperature of the reactant stream;
• and
• exposing the reactant stream to the catalyst system in the reaction zone at a temperature of 1000° C. or more to form a product stream comprising H2, a direction of flow for the reactant stream within the reaction zone being reversed relative to a direction of flow for the mixture.

A method for reforming hydrocarbons, comprising:

• reacting a mixture comprising fuel and 0.1 vol % or more of O2 under combustion conditions in a combustion zone within a reactor to heat one or more surfaces in a reaction zone to a regenerated surface temperature of 1100° C. or more, the reaction zone comprising a catalyst system supported on one or more surfaces of a support structure, the catalyst system comprising i) Ni and Al2O3, ii) NiO and Al2O3, iii) NiAl2O4, or iv) a combination of two or more of i), ii) and iii);
• exposing the catalyst system to a gas flow comprising 100 mol % to 250 mol % of a stoichiometric molar amount of O2 for conversion of the molar amount of Ni in the catalyst system from metallic Ni to NiO, NiAl2O4, or a combination thereof;
• exposing a reactant stream comprising a reformable hydrocarbon to the one or more surfaces in the reaction zone to increase the temperature of the reactant stream;
• and
• exposing the reactant stream to the catalyst system in the reaction zone at a temperature of 1000° C. or more to form a product stream comprising H2,
• wherein the 0.1 vol % or more of O2 comprises an excess of O2 of 20 mol % or more relative to the stoichiometric amount of O2 for combustion of the fuel, and wherein the exposing the catalyst system to a gas flow comprises exposing the catalyst system to the 0.1 vol % or more of O2.