Method to remove ammonia using a proton-conducting ceramic membrane

This invention relates to the catalytic decomposition of ammonia (NH ) from the gas feed to a turbine combustor, as a method to reduce NO emissions in fossil-fuel fired power plants. In this invention, the efficient removal of ammonia from a gas mixture by catalytic decomposition is achieved by: 1) making a tube-shaped proton-conducting ceramic membrane; 2) coating the inner surface of the membrane with a film of material that will catalyze the reactions: 2NH →N +3H ; and, 3) passing the 2H+ ions through the internal space of the coated tube. An apparatus and method for decomposing NH. A fluid containing NHis passed in contact with a tubular membrane that is a homogeneous mixture of a ceramic and a first metal, with the ceramic being selected from one or more of a cerate having the formula of M′CeM″, zirconates having the formula M′ZrM″O, stannates having the formula M′SnM′O, where M′ is a group IIA metal, M″ is a dopant metal of one or more of Ca, Y, Yb, In, Nd, Gd or mixtures thereof and is a variable depending on the concentration of dopant and is in the range of from 0.001 to 0.5, the first metal is a group VIII or group IB element selected from the group consisting of Pt, Ag, Pd, Fe, Co, Cr, Mn, V, Ni, Au, Cu, Rh, Ru and mixtures thereof. The tubular membrane has a catalytic metal on the side thereof in contact with the fluid containing NHwhich is effective to cause NHto decompose to Nand H. When the Hcontacts the membrane Hions are formed which pass through the membrane driving the NHdecomposition toward completion.