An antipollution device in automobiles which contains a chemical catalyst for oxidizing the pollutant exhaust gases (carbon monoxide, nitrogen oxides, and hydrocarbons), thereby converting them to harmless products (carbon dioxide, nitrogen, and water vapor).

触媒催化转化器(一种汽车的防止污染装置，内藏化学催化用来氧化造成污染的癈气，如一氧化碳、氮氧化物及碳氢化合物等，把它们转化为无害物，如二垂化碳、氮及水蒸气)。