Benés Mario, Pozo Guillermo, Abián María, Millera Ángela, Bilbao Rafael, Alzueta María U
Aragón Institute of Engineering Research (I3A), Department of Chemical and Environmental Engineering, University of Zaragoza, 50018 Zaragoza, Spain.
Energy Fuels. 2021 May 6;35(9):7193-7200. doi: 10.1021/acs.energyfuels.0c03387. Epub 2021 Jan 20.
The possibility of using ammonia (NH), as a fuel and as an energy carrier with low pollutant emissions, can contribute to the transition to a low-carbon economy. To use ammonia as fuel, knowledge about the NH conversion is desired. In particular, the conversion of ammonia under pyrolysis conditions could be determinant in the description of its combustion mechanism. In this work, pyrolysis experiments of ammonia have been performed in both a quartz tubular flow reactor (900-1500 K) and a non-porous alumina tubular flow reactor (900-1800 K) using Ar or N as bath gas. An experimental study of the influence of the reactor material (quartz or alumina), the bulk gas (N or Ar), the ammonia inlet concentration (1000 and 10 000 ppm), and the gas residence time [2060/ (K)-8239/ (K) s] on the pyrolysis process has been performed. After the reaction, the resulting compounds (NH, H, and N) are analyzed in a gas chromatograph/thermal conductivity detector chromatograph and an infrared continuous analyzer. Results show that H and N are the main products of the thermal decomposition of ammonia. Under the conditions of the present work, differences between working in a quartz or non-porous alumina reactor are not significant under pyrolysis conditions for temperatures lower than 1400 K. Neither the bath gas nor the ammonia inlet concentration influence the ammonia conversion values. For a given temperature and under all conditions studied, conversion of ammonia increases with an increasing gas residence time, which results into a narrower temperature window for NH conversion.
将氨（NH₃）用作燃料和低污染物排放的能量载体，有助于向低碳经济转型。要将氨用作燃料，需要了解氨的转化情况。特别是，氨在热解条件下的转化可能是描述其燃烧机理的决定性因素。在这项工作中，使用氩气或氮气作为载气，在石英管式流动反应器（900 - 1500 K）和无孔氧化铝管式流动反应器（900 - 1800 K）中进行了氨的热解实验。对反应器材料（石英或氧化铝）、主体气体（氮气或氩气）、氨入口浓度（1000和10000 ppm）以及气体停留时间[2060 / (K) - 8239 / (K) s]对热解过程的影响进行了实验研究。反应后，在气相色谱仪/热导检测器色谱仪和红外连续分析仪中分析生成的化合物（NH₃、H₂和N₂）。结果表明，H₂和N₂是氨热分解的主要产物。在本工作的条件下，对于低于1400 K的热解温度，在石英或无孔氧化铝反应器中工作的差异不显著。载气和氨入口浓度均不影响氨的转化率。在给定温度和所有研究条件下，氨的转化率随气体停留时间的增加而增加，这导致NH₃转化的温度窗口变窄。
