Herein disclosed is an apparatus, which comprises (1) a first cylindrical, porous, catalytic rotor symmetrically positioned about an axis of rotation and surrounding a first interior space; wherein the first porous catalytic rotor comprises a first catalyst; (2) an outer casing, wherein the outer casing and the rotor are separated by an annular space; (3) a motor configured for rotating the rotor about the axis of rotation; (4) a feed inlet line; and (5) a first outlet line, wherein the first outlet line is fluidly connected with the annular space. Herein disclosed is also a method comprising: (1) passing a feed gas comprising at least one gaseous reactant through a porous, catalytic rotor, wherein the porous, catalytic rotor is permeable to the at least one gaseous reactant and is made from or contains a catalyst effective for catalyzing a first reaction; and (2) extracting a first desired product.