Characterization of tars from variable heating rate pyrolysis of maceral concentrates
Characterization of tars from variable heating rate pyrolysis of maceral concentrates
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DOI：
10.1016/0016-2361(93)90368-c
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发表时间：
1993
期刊：
影响因子：
7.4
通讯作者：
Chun-Zhu Li;K. Bartle;R. Kandiyoti
中科院分区：
文献类型：
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作者：
Chun-Zhu Li;K. Bartle;R. Kandiyoti
测定了来自林比煤的一组显微组分浓缩物的热解的焦油的产物产率和结构，并将其作为加热速率（1和1000 K s-1）和温度（400-900 °C）的函数进行了比较。开发了一种新的捕集器，用于收集和定量回收在常压丝网热解实验期间产生的焦油，从而使焦油的捕获和回收能够紧密地反映所产生的初级焦油的特性。产率从所有三个显微组分浓缩物被发现增加加热速率，但liptinite浓缩物显示出最小的敏感性。焦油表征进行尺寸排阻色谱和紫外荧光光谱。分子量分布的比较表明，liptinite浓缩焦油含有较大的馏分比相应的镜质组和惰质组浓缩焦油的大分子量单位。使用蒸发分析仪作为质量检测器获得的400 ° C和500 °C实验中的脂沥青体浓缩焦油的分子量分布显示存在大量未被设置在254 nm处并串联使用的u. v.检测器检测到的材料，这表明在该区域中鉴定的材料主要是脂肪族/氢化芳族的。在快速加热实验（1000 K s−1）中，这种材料倾向于随着热解温度从400-500 °C增加到600-900 °C而迅速减少，这表明颗粒内破坏。紫外荧光光谱的结果表明，镜质组和脂质组焦油中存在基本相似的芳族簇尺寸分布;然而，镜质组浓缩物焦油的光谱强度更大，表明镜质组焦油中存在更高浓度的芳族簇和/或极性。
Product yields and structures of tars from the pyrolysis of a set of maceral concentrates derived from Linby coal were determined and compared as a function of heating rate (1 and 1000 K s−1) and temperature (400–900 °C). A new trap was developed for the collection and quantitative recovery of tars evolved during atmospheric pressure wire-mesh pyrolysis experiments, allowing the capture and recovery of tars expected to reflect closely the characteristics of evolved primary tars. Yields from all three maceral concentrates were found to increase with increasing heating rate, but the liptinite concentrate showed the smallest sensitivity. Tar characterization was undertaken with size exclusion chromatography and u.v. fluorescence spectroscopy. Comparison of molecular mass distributions suggested that liptinite concentrate tars contain greater fractions of large molecular mass units than corresponding vitrinite and inertinite concentrate tars. Molecular mass distributions of liptinite concentrate tars from experiments at 400 and 500 °C, obtained using an evaporative analyser as mass detector, showed the presence of substantial quantities of material not detected by a u.v. detector, set at 254 nm and used in tandem, suggesting that the material identified in this region is predominantly aliphatic/hydroaromatic in character. In fast heating experiments (1000 K s−1), this material tended to diminish rapidly with increasing pyrolysis temperature from 400–500 °C to 600–900 °C, suggesting intraparticle destruction. Results from u.v. fluorescence spectroscopy suggest the presence of substantially similar aromatic cluster size distributions in vitrinite and liptinite tars ; greater intensities of spectra from vitrinite concentrate tars suggest, however, the presence of greater concentrations of aromatic clusters and/or polars within vitrinite tars.