Diesel engines are playing a vital role in the field of transportation and power generation. In the present world, much research is going on in the field of renewable energy to replace conventional sources of energy. But it is not very easy to replace diesel engines with other engines when power and reliability are the factors that matter. The emissions from diesel engines are very harmful to the environment and to human health. The major emissions are NOx and smoke which need to be controlled in an effective manner. This experimental investigation was carried out to find out suitable additives for reduced emissions without altering the performance of diesel engines. For that purpose, detailed experiments were conducted with different sets of nitromethane-n-butanol-diesel blends.