Purification of engine bleed air

A method of purifying bleed air from an engine, comprising the steps of:

• heating the bleed air to produce heated bleed air at a temperature between 220° F. and 450° F.;
• reacting the heated bleed air in a bleed air catalytic reactor bed comprising a noble metal catalyst supported on a washcoat of metal oxide to produce reacted bleed air containing reacted contaminant components;
• and
• releasing the reacted bleed air.

A method of purifying bleed air from an engine which produces a bleed air stream and an exhaust gas stream, the method comprising the steps of:

• heating the bleed air to produce heated bleed air to a temperature between 220° F. and 450° F. by placing the bleed air and the exhaust gas in thermal contact but not in fluid contact by flowing each through a different chamber of a heat exchanger;
• reacting the heated bleed air in a bleed air catalytic reactor bed comprising a noble metal catalyst supported on a washcoat of metal oxide to produce reacted bleed air in which;
• carbon contaminants in the heated bleed air are reacted to CO2;
• hydrogen contaminants in the heated bleed air are reacted to H2O;
• contaminating heteroatoms are reacted to one of an acid gas and an acid-gas precursor;
• chlorine contaminants in the heated bleed air are reacted to HCl, and
• nitrogen contaminants in the heated bleed air are reacted to at least one of dinitrogen, nitrous oxide, nitric oxide, and nitrogen dioxide;
• and releasing the reacted bleed air.

Apparatus for purifying bleed air from an engine which produces a bleed air stream and an-exhaust gas stream, the apparatus comprising:

• a heat exchanger for heating the bleed air to produce heated bleed air at a temperature between 220° F. and 450° F. by placing the bleed air and the exhaust gas in thermal contact but not in fluid contact by flowing each through a different chamber of a heat exchanger;
• and
• a bleed air catalytic reactor bed comprising a noble metal catalyst supported on a washcoat of metal oxide for reacting the heated bleed air to produce reacted bleed air in which;
• carbon contaminants in the heated bleed air are reacted to CO2;
• hydrogen contaminants in the heated bleed air are reacted to H2O;
• contaminating heteroatoms are reacted to one of an acid gas and an acid-gas precursor;
• chlorine contaminants in the heated bleed air are reacted to HCl, and
• nitrogen contaminants in the heated bleed air are reacted to at least one of dinitrogen, nitrous oxide, nitric oxide, and nitrogen dioxide.

A method of purifying bleed air from an engine which produces a bleed air stream and an exhaust gas stream having a temperature warmer than the bleed air stream, the method comprising the steps of:

• heating the bleed air to produce heated bleed air to a temperature between 220° F. and 450° F. by placing the bleed air and the exhaust gas in thermal contact but not in fluid contact by flowing each through a different chamber of a heat exchanger;
• reacting the heated bleed air in a bleed air catalytic reactor bed comprising a noble metal catalyst supported on a washcoat of metal oxide to produce reacted bleed air in which;
• carbon contaminants in the heated bleed air are reacted to CO2;
• hydrogen contaminants in the heated bleed air are reacted to H2O;
• contaminating heteroatoms are reacted to one of an acid gas and an acid-gas precursor;
• chlorine contaminants in the heated bleed air are reacted to HCl, and
• nitrogen contaminants in the heated bleed air are reacted to 20 at least one of dinitrogen, nitrous oxide, nitric oxide, and nitrogen dioxide;
• releasing the reacted bleed air;
• reacting the exhaust gas in an exhaust gas catalytic reactor bed to produce a purified exhaust gas;
• releasing the purified exhaust gas.