溶剂特性对淖毛湖煤加氢液化中间产物反应行为的影响

为探究溶剂特性对煤加氢液化中间产物反应行为的影响，以新疆淖毛湖煤作为原料，四氢萘、循环溶剂及十氢萘作为供氢溶剂，在高压搅拌釜中进行直接加氢液化实验，并运用电子顺磁共振手段分析了中间产物-沥青质的自由基浓度的变化。结果表明，四氢萘溶剂中沥青质随反应温度的升高在大量生成的同时又被转化，产率从290℃的12.92%到350℃的最大34.13%再到430℃的15.98%；循环溶剂中沥青质产率先持续上升，290℃即有31.89%，400℃达到最大47.96%，之后由于结焦反应降低至33.90%。十氢萘溶剂中沥青质产率变化趋势与四氢萘一致。三种溶剂中沥青质自由基浓度的变化趋势相同，均在350℃达到最大值，分别是1.778×10¹⁸、2.323×10¹⁸和1.930×10¹⁸/g，整体上看循环溶剂数值要高于四氢萘，十氢萘介于两者之间。而四氢萘及循环溶剂中沥青质的g值在2.00323-2.00403，变化趋势与液化气体产物中CO_x含量变化相吻合。

Effect of solvent characteristics on reaction behavior of hydroliquefaction intermediate products from Naomaohu coal

To explore effect of solvent characteristics on reaction behavior of coal hydroliquefaction intermediate products, coal from Naomaohu in Xinjiang as raw material, tetralin, recycle solvent and decalin as hydrogen-donor solvents, hydroliquefaction experiments were performed in a high-pressure stirred reactor, and change of free radical concentration of asphaltene was analyzed by EPR. The results indicate that asphaltene in tetralin is formed in large quantities and transformed at the same time with increasing reaction temperature, the yield is from 12.92% at 290 ℃ to a maximum of 34.13% at 350 ℃ and then to 15.98% at 430 ℃. The asphaltene yield in recycle solvent continues to rise first, with 31.89% at 290 ℃ and a maximum of 47.96% at 400 ℃, and then decreases to 33.90% due to coking reaction. The change of asphaltene yield in decalin is consistent with that in tetralin. The change of free radical concentration of asphaltene is the same in three solvents, reaching the maximum at 350 ℃, which is 1.778×10¹⁸, 2.323×10¹⁸ and 1.930×10¹⁸/g respectively. On the whole, the values of free radical concentration of asphaltene in recycle solvent are higher than those in tetralin, and that in decalin is between the two solvents. But the g value in tetralin and recycle solvent is between 2.00323 and 2.00403, and the change is consistent with that of CO_x content in gas products.