Nitrous oxide of air separation plant is harmful to air separation plant to some extent. Nitrous oxide is a blocking component in air separation system. The content of nitrous oxide in liquid oxygen is too high and easy to separate out, blocking the small channel of heat exchanger, causing local micro explosion, thus causing equipment damage of main cooling liquid leakage. At present, the molecular sieve function of the air separation purification system has the adsorption requirements for nitrous oxide of air separation plant. The adsorption rate of the new molecular sieve for nitrous oxide in the air can reach more than 98%. Although nitrous oxide is not a component involved in combustion and explosion, it will cause combustion and explosion accidents and equipment damage.