The effect of functional forms of nitrogen on fuel-NO x emissions

Abstract

This work explores the effects of different nitrogen functional forms on fuel-NOx emissions at 900 °C. The majority of tests are performed with an excess air coefficient of 1.4. Fuel-NOx is detected by measuring N-(1-naphthyl) ethylenediamine dihydrochloride (C₁₂H₁₆Cl₂N₂) 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-NOx emissions increase by using less activation energy and nitrogen-containing groups with poor thermal stability. It is determined that fuel-NOx 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-NOx in all of the raw materials studied. More pyrrole than pyridine in coal lead to high yields of fuel-NOx. The lowest yields of fuel-NO x are obtained using polyurethanes in waste-PU.

Experimental and kinetic modeling study of the pyrolysis and oxidation of diethylamine

“…compounds which are derivatives of ammonia by replacing one or more hydrogen atoms by a substituent such as an alkyl group. The conversion of these amines can lead to the formation of NOx, even more so compared to nitrogencontaining aromatic compounds [17][18][19]. Thus, even though they are present in bio-oils only in small quantities (a few percent), their conversion should be studied in depth.…”

Heavy metal accumulation and its spatial distribution in agricultural soils: evidence from Hunan province, China

“…Moreover, 64.8% of the 1.4 million hm 2 of sewage-irrigated agricultural land suffers from heavy metal contamination and every year as much as 12 million t of grain is contaminated by heavy metals in China. 4,5 Given the severe situation of soil heavy metal contamination, domestic and overseas scholars have introduced advanced mathematical statistics and spatial analysis methods to investigate the current status and sources of soil heavy metal contamination in different regions of China [6][7][8] and under various land-use types [9][10][11] as well as the forms, migration, and transformations of heavy metals. 12,13 Overall, research into heavy metal contamination in soils has been continuously intensied and the research results are tending to be enriched, which have provided important grounds for the prevention and treatment of heavy metal contamination in China.…”

“…Consequently, the status of heavy metal contamination in soils of entire Hunan province cannot therefore be revealed. 5,6 Food is the basis of human survival and, as the medium for crop growth, soil is the basis of food. Therefore, heavy metal accumulation in agricultural land has the potential to enter human bodies through human intake of agricultural products.…”

“…Consequently, the status of heavy metal contamination in soils of entire Hunan province cannot therefore be revealed. 5,6 …”

Investigation of N Transfer during Coal Char Oxidation by Reactive Molecular Dynamics

“…Thus, in the investigation of nitrogen transformation in volatile combustion, it is straightforward to employ HCN/NH 3 /pyrrole/pyridine as model compounds by using state-of-the-art experiments 7 or ab initio-based calculation methods. 8 The detailed description of nitrogen functions converting to NO x during the volatile oxidation process was reviewed by other researchers. 9 The role of NO-char reactions has been significant in connection with combustor modeling as well as in the design of postcombustion for NO x control strategies.…”