The aim is to significantly extend the possible solutions for the elimination of environmentally undesirable components in the tail gas from nitric acid production by using for selective reduction NOx also hydrocarbons (CHx-SCR NOx), and to develop process-reliable catalyst for decomposition of N2O in the secondary process, namely at temperatures above 800 °C. The proposed selective reduction process using C1-C3 instead of NH3 is still lacking among the applicable procedures and would fill the gap in the range of technologies offered for this aim. The solution of these two tasks will provide optimization of the technology for elimination of NOx/N2O under various conditions of nitric acid production and minimize costs in the management of these processes. Keywords in English: production of nitric acid- protection of environment- selective catalytic reduction of NOx by hydrocarbons- high temperature decomposition of N2O- zeolitic catalysts- oxidic catalysts. Participants on the project: Number of recipients 1 Number of subrecipients 2 Contractor: Euro Support Manufacturing Czechia, s.r.o. Participants: Chemoprojekt, a.s. and JHI PC