采用热重-红外联用(TG-FTIR)技术研究了煤直接液化残渣(DCLR)的热解特性, 重点对其热解过程气体的析出规律进行了分析讨论。 研究表明, 液化残渣热失重分为三个阶段, 在405.10 ℃以前为残渣热解第一阶段; 405.10～523.83 ℃主要为高沸点油和沥青质等的大量热分解阶段, 当温度达到478.45 ℃时, 失重速率达到最大值, 此时失重量约占总失重的40.27%; 523.83 ℃以后残渣的失重曲线较为平缓, 失重量约占总失重的50.55%, 主要由产物的二次分解和矿物质的热分解所造成。 热解过程气体产物的析出也分为三个阶段, 第一阶段主要释放的是H2O和CO2, 第二阶段中析出的主要为CO2, CH4, CO、 H2O和少量SO2, 同时在458.4～791.9 ℃范围内伴随着焦油的大量析出, 第三阶段主要是CO2, CO和H2O的析出。 CO2的释放主要归功于含氧杂环或OCO等含氧基团的断裂, 而CO的释放主要由醚键以及含氧杂环热分解造成, 脂肪烃的热分解是CH4释放的主要原因。

The pyrolysis characteristic of direct coal liquefaction residue (DCLR) was studied with thermo-gravimetric analyzer (TG) coupled with Fourier transform infrared spectrometry (FTIR), which is used to discuss the emitted regulation of gaseous product during pyrolysis process. This research shows that the weight loss process of DCLR can be divided into three stages: the first is before the temperature of 405.10 ℃; stage from 405.10 to 523.83 ℃ which is mainly pyrolysis of high boiling point of oil and asphaltene et al, and the total weight loss of DCLR can up to 40.27% when the temperature reaches 478.45 ℃, meanwhile the mass loss rate is maximum; after 523.83 ℃, the weight loss curve becomes gentle and the total weight loss of DCLR reaches 50.55% , which is due to the secondary cracking of residue and decomposition of mineral matter. The emitted process of gaseous product can be divided into three stages too: the first is the generation of H2O and CO2, the second stage mainly emitted CO2,CH4,CO,H2O and a small quantity of SO2, in which plenty of tar is generated from 458.4 to 791.9 ℃, the final stage mainly generated CO2, CO and H2O. CO2 mainly emitted owing to the cracking of oxygenheterocycle and OCO or other oxygen-containing groups, CO emitted due to cracking of ether and oxygenheterocycle, and CH4 generated as a result of cracking of aliphatic hydrocarbon.