The effect of functional forms of nitrogen on fuel-NOx emissions

This work explores the effects of different nitrogen functional forms on fuel-NO x emissions at 900 °C. The majority of tests are performed with an excess air coefficient of 1.4. Fuel-NO x is detected by measuring N-(1-naphthyl) ethylenediamine dihydrochloride (C 12 H 16 Cl 2 N 2 ) via spectrophotometry. The different functional forms of nitrogen in the raw materials are identified by using X-ray photoelectron spectroscopy (XPS). A reliable density functional theory (DFT) method at the B3LYP/6-311++G** level is employed to investigate the reaction pathways of all functional forms of nitrogen during combustion. The results indicate that the functional forms of nitrogen influence the formation of nitrogen oxides. While under the same experimental conditions, fuel-NO x emissions increase by using less activation energy and nitrogen-containing groups with poor thermal stability. It is determined that fuel-NO x emissions vary in the following order: glycine > pyrrole > pyridine > methylenedi- p -phenylene diisocyanate (MDI). Glycine is the chain structure of amino acids in waste-leather and has low activation energy and poor thermal stability. With these properties, it is noted that glycine produces the most fuel-NO x in all of the raw materials studied. More pyrrole than pyridine in coal lead to high yields of fuel-NO x . The lowest yields of fuel-NO x are obtained using polyurethanes in waste-PU.