To improve cleaning performance to hydrocarbons(HC) and simultaneously suppress exhaust of NOx under such a condition that the temperature of exhaust gas is low at such a time when an internal engine is started.
An exhaust gas cleaning device contains an HC adsorbing material, a NOx holding material and catalyst components, and lithium as the NOx holding material in an amount of 0.05 to 1.0 mol per 11 of the exhaust gas cleaning device. An HC adsorbing and cleaning type catalyst is constituted of the HC adsorbing material and a ternary catalyst which are each supported on a carrier in the layered state and the NOx holding material which is supported on at least one of the HC absorbing material and the ternary catalyst components. The layer of the HC adsorbing material is arranged at the downside of the layer of the ternary catalyst component, and lithium is contained as the NOx holding material in an amount of 0.05 to 1.0 mol per 1 l of the HC adsorbing and cleaning type catalyst. Further, a method of cleaning the exhaust gas comprises using the exhaust gas cleaning device or the HC adsorbing and cleaning type catalyst.
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