摘要 |
A particulate filter may include a first layer composed of a first hydrocarbon trap absorbing hydrocarbon contained in an exhaust gas at a low temperature and a second layer composed of a first oxidizing catalyst oxidizing the hydrocarbon contained in the exhaust gas. The hydrocarbon absorbed at the first layer may be released at a high temperature, and the released hydrocarbon may be oxidized at the second layer to raise a temperature of the exhaust gas. An exhaust system may include an oxidation catalyst and the particulate filter. The oxidation catalyst may be a diesel oxidation catalyst comprising a third layer composed of a second hydrocarbon trap absorbing the hydrocarbon contained in the exhaust gas at a low temperature and a fourth layer composed of a second oxidizing catalyst oxidizing the hydrocarbon contained in the exhaust gas.
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