| abstract |
The invention relates to the use of at least one formic acid alkyl ester of the formula HCO-OR, where R is an alkyl radical having 1 to 6 carbon atoms or an aryl radical having 6 carbon atoms, and / or at least one oxymethylene dimethyl ether or polyoxymethylene dimethyl ether (OME) of the formula H 3 CO- (CH 2 O) n -CH 3 , where 1 ≤ n ≤ 5, as an additive to the fuel for an internal combustion engine or as a component to be injected in addition to the fuel into a combustion chamber of an internal combustion engine to reduce NO x emissions when operating the internal combustion engine compared to its operation only with the fuel, wherein during operation of the internal combustion engine, a portion of an exhaust gas generated during operation of the internal combustion engine is returned to / into the combustion chamber of the internal combustion engine. |