Method and device for depolluting combustion gases

A depollution device of the combustion gases placed along the exhaust circuit of said gases, assembled on a motor vehicle, comprising a boiler (1) in which the thermal energy supplied by the exhaust gases produces the evaporation of a mixture coolant-absorbent, a liquid separator (3) situated at the exit of the top part of the boiler (1), an evaporator (9) allowing the cooling of the exhaust gases followed by an absorber (11) for the recombination of the mixture coolant-absorbent, characterised in that it comprises a catalyst (23) placed at the exit of the engine's gases and before the boiler (1), an expansion valve (8) placed upstream of the evaporator (9) the latter being assembled on an exhaust box (10) and upstream of the absorber (11) situated at the exit of the boiler (1), a pump (12) downstream of the absorber (11) to send the mixture coolant-absorbent into the boiler (1) and a condenser (4) placed between the liquid separator (3) and the expansion valve (8) that transforms in liquid form and thanks to the pressure produced by the system the vapours filtered by the liquid separator (3), the latter being destined to only let pass the vapours of the coolant.