The thesis addresses the issue of pollutant emission from the compression ignition engines. To enable the research of pollutant emission reduction through advanced combustion process, a new intake manifold was designed. At the same time, existing intake manifold and fuel system were adapted. Afterwards, engine parameters were optimized to establish low-temperature combustion with a direct injection of diesel fuel being a representative of high reactivity fuels and tire pyrolysis oil (TPO) being a representative of low reactivity fuels. TPO is an alternative fuel that could potentially replace diesel fuel in specific applications. It is shown in the thesis, that partially premixed combustion of TPO can be established without the addition of additives or mixing with diesel fuel. When using diesel fuel, significant reduction of particulate matter and nitrogen oxides can be achieved by relatively small changes in engine control strategy. Moreover, it is demonstrated that partially premixed combustion of diesel fuel has a relatively small impact on engine efficiency. On the other hand, reduction in emissions of pollutants does not feature significant reduction of pollutant emissions when using TPO, as the entire spectrum of fuel properties – not just lower reactivity – has an important role in pollutant formation phenomena. Presented results that provide the basis for establishing proper engine control strategy allowing to simplify complicated exhaust gas aftertreatment systems while still complying with emission limits.