Protected alloy surfaces in microchannel apparatus and catalysts, alumina supported catalysts, catalyst intermediates, and methods of forming catalysts and microchannel apparatus

A method of conducting a chemical reaction in a microchannel reactor or separator, comprising:

• a microchannel defined by at least one microchannel wall;
• a post-assembly coating of aluminide disposed over the at least one microchannel wall,
• a layer alumina disposed over the layer of aluminide;
• and
• a catalytic material disposed over the layer of alumina,
• wherein the microchannel has a rectangular cross-section and wherein the thickness of the coating at a corner of the rectangle is within 25% of the coating thickness measured at the midpoint between two corners of the rectangle;
• the method comprising a step of passing a reactant into the complex microchannel and reacting the reactant in the microchannel to form at least one product.

A method of forming a catalyst, comprising:

• providing an article comprising an aluminide surface;
• adding a sintering aid to alumina to form an alumina layer with sintering aid disposed over the aluminide surface;
• and
• heating the article with an alumina layer with sintering aid;
• and subsequently depositing a catalyst material.

A method of forming protected surfaces, comprising:

• providing an article comprising an aluminide surface;
• heating the article comprising an aluminide surface to at least about 800° C. in an inert or reducing atmosphere;
• and, subsequently,
• exposing the aluminde surface to an oxidizing gas at a temperature of at least about 800° C. to grow an oxide layer.