doi:10.16186/j.cnki.1673-9787.2020050029

Received:2020/05/11

Revised:2020/08/03

Published:2022/01/10

Comparative analysis of oxidation characteristics of raw coal，primary oxidized coal and secondary oxidized coal with different particle sizes

YANG Kai1,2,3, YANG Shengqiang1,2,3, XU Qin1,2,3

1.State Key Laboratory of Coal Recourse and Safe Mining， China University of Mining & Technology， Xuzhou  221116 ， Jiangsu， China；2.Key Laboratory of Gas and Fire Control for Coal Mines， China University of Mining & Technology， Xuzhou  221116 ， Jiangsu， China；3.School of Safety Engineering ，China University of Mining & Technology， Xuzhou  221116， Jiangsu， China

Abstract: In order to reveal the mechanism of oxidation on the structure of coal samples with different particle sizes，electron spin resonance spectroscopy( ESR) and Fourier infrared spectroscopy( FTIR) were used to analyze the raw coal，primary oxidized coal and secondary oxidized coal with 5 particle sizes，and the influences of oxidation on the types of free radicals，the content distribution of free radicals and functional groups in coal molecules were studied． The results showed that the number of free radical types( g factor) of coal samples of each particle size was primary oxidized coal> secondary oxidized coal> raw coal，the value of free radical con centration was secondary oxidized coal> primary oxidized coal> raw coal，and the smaller the coal particle size was，the more obvious the change trend was． When the coal particle size was> 0.124 mm，the change rule of C—O content was secondary oxidized coal> primary oxidized coal> raw coal，while when the coal particle size was <0.124 mm，the change rule of C—O content was primary oxidized coal> secondary oxidized coal> raw coal． The change rule of aliphatic hydrocarbon content in coal samples with various particle sizes was that the primary coal> and the secondary coal> Meanwhile，and the difference of aliphatic hydrocarbon between the primary coal and the secondary coal decreased with the decrease of particle sizes.

Key words:coal particle size;secondary oxidation;free radical;functional group

 不同粒径原煤、初次氧化煤与二次氧化煤氧化特性对比分析_杨锴.pdf