EXHAUST GAS PURIFIER

摘要

A first selective reduction catalyst including a silver-based catalyst is provided in an exhaust pipe of an engine. An ozone generation device generates ozone by using oxygen in the atmosphere, and a hydrocarbon-based liquid supply device supplies a hydrocarbon-based liquid. A part of NO in the exhaust gas flowing through the exhaust pipe is oxidized to NO2 with the ozone generated by the ozone generation device, and said NO2 is supplied to the first selective reduction catalyst. Also, a part of the hydrocarbon-based liquid supplied by the hydrocarbon-based liquid supply device is partially oxidized, with ozone generated by the ozone generation device, to an active reducing agent including an oxygen-containing hydrocarbon such as aldehyde, and this active reducing agent is supplied to the first selective reduction catalyst.

主权项

1. An exhaust gas purifier comprising:
a first selective reduction catalyst that is provided in an exhaust pipe of an engine and that includes a silver-based catalyst; an ozone generation device that generates ozone by using oxygen in an atmosphere or an exhaust gas; and a hydrocarbon-based liquid supply device that supplies a hydrocarbon-based liquid, a part of NO in the exhaust gas flowing through the exhaust pipe is oxidized to NO2 with ozone generated by the ozone generation device, said NO2 is supplied to the first selective reduction catalyst, a part of the hydrocarbon-based liquid supplied by the hydrocarbon-based liquid supply device is partially oxidized, with the ozone generated by the ozone generation device, to an active reducing agent including an oxygen-containing hydrocarbon containing either or both of aldehyde and alcohol, and the active reducing agent is supplied to the first selective reduction catalyst.