The physical and chemical properties of N 2 O and methods for its trapping and decomposition are examined. It is found that organic solvents, water, hydrazine hydrate, and a solution of potassium bichromate in sulfuric acid dissolve N 2 O but its stabilization by this method is unreliable. Catalytic decomposition upon heating is acknowledged to be an effective method of neutralizing N 2 O. Different composite materials, including those containing d and ƒ elements, were studied as catalysts. It was found that suitable composites for catalytic decomposition of N 2 O are SiO 2 –Cu, Al 2 O 3 –Ni at 150°C and Al 2 O 3 –Cu, Al 2 O 3 –Fe, Al 2 O 3 –Ni, and SiO 2 –Cu at 250°C. It was shown that the passage of ethanol vapors above the composites at the indicated temperature increases the degree of decomposition of N 2 O by a factor of 10. The results obtained were used to develop a gas-purification system in the technology for reprocessing spent nitride fuel.