Tao Zhou,Hang Xiao,Weifeng Peng,Bo Liang,Yao Liu,Jiangbo Lv,Jianghuai Hu,Ke Zeng,Gang Yang
The pyrolysis behaviors of l -tyrosine-based phthalonitrile(TPN) resin were investigated by thermogravimetric-Fourier transform infrared spectrometry-mass spectrometry (TG-FTIR-MS) and Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The small molecules produced during pyrolysis process of TPN resin were tracked in real time by TG-FTIR-MS. The larger molecules ( m / z > 40) from fast pyrolysis at 900 °C of the TPN resin using Py-GC/MS were identified. From TG-FTIR-MS and Py-GC/MS results, the production pathways of pyrolysis products such as CO 2 , CO, NH 3 , benzonitrile and phenol were analyzed. The possible pyrolysis mechanism of TPN resin under non-oxidizing gaseous environment was proposed. The results of this study provide the useful information for designing the molecular structure of l -tyrosine-based polymers which possessing high thermal stability.
Li Zhou,Fashe Li,Wenchao Wang,Huicong Zhang,Yaozong Duan,Hua Wang
Phospholipids, as key trace constituents of biodiesel, can have complex effects on the performance of biodiesel. Exploring the mechanism of their influence on the pyrolysis and oxidation characteristics of biodiesel is crucial for controlling the generation and emission of pollutants. To this end, this study employed TG-FTIR-MS experimental technology and the ReaxFF-MD simulation method to investigate the effects of phosphatidylethanolamine (PE) on the activation energy ( E a ), gaseous product generation, and mechanism of Jatropha biodiesel pyrolysis and oxidation reactions. The results indicated that the addition of 400 ppm PE can reduce the pyrolysis E a of Jatropha biodiesel from 87.25 kJ/mol to 80.67 kJ/mol, consistent with simulated E a of 93.35 kJ/mol and 81.81 kJ/mol, respectively. This notably promoted the initial oxidation stage of the Jatropha biodiesel reaction, facilitating the generation of oxidation products such as CO and C 2 H 4 . In the pyrolysis reaction, PE promoted C 2 H 4 formation, primarily through reactions involving hydrocarbon small free radicals. In the oxidation reaction, the addition of PE increased the number and variety of active free radicals in the system, with the formation reactions of H 2 O and CH 2 O involving phosphorus-containing oxygen groups. Furthermore, a small amount of nitrogenous free radicals participates in the formation reactions of C 2 H 4 and CO.
Zhanshi Ni,Haobo Bi,Chunlong Jiang,Hao Sun,Wenliang Zhou,Zhicong Qiu,Qizhao Lin
Faced with increasingly severe environmental and energy issues, the development and utilization of solid waste have become a trend. In this study, a thermogravimetric-Fourier infrared spectrometer-mass spectrometer (TG-FTIR-MS) was used to carry out the co-pyrolysis experiment of coal slime and cellulose. The samples with mass mixing ratios of 0:10, 1:9, 3:7, 5:5, 7:3, 9:1, and 10:0 were pyrolyzed in N 2 atmosphere. The percentages of mass loss during the pyrolysis of coal slime and cellulose were 15.69 and 94.28%, respectively. The addition of cellulose to the coal slime could significantly improve the pyrolysis performance of the sample. It was detected by FTIR that the pyrolysis of the blends mainly formed C=O-containing compounds. MS was used to monitor the ion current intensity of gaseous products of sample pyrolysis online. The average activation energy of the reaction between coal slime and cellulose calculated by the Kissinger-Akahira-Sunose method were 237.59 kJ/mol and 174.06 kJ/mol, respectively. The principal component 1 and principal component 2 dominated the co-pyrolysis process of coal slime and cellulose. The MAE, RMSE, and R 2 of the artificial neural network prediction model for predicting the pyrolysis process of the sample were 0.5249, 0.8244, and 0.9994, respectively. This research provided basic theory and data support for understanding the co-pyrolysis of coal slime and biomass.