白石湖煤加氢液化过程含氮化合物转化行为研究

Conversion behavior of nitrogenous compounds in hydroliquefaction of Baishihu coal

对煤加氢液化过程中含氮化合物的转化行为及在气、液、固三相产物中的赋存形态进行研究,可为低阶煤的高效洁净利用奠定理论基础。在0.01 t/d连续试验装置完成新疆白石湖煤加氢液化连续试验,采用微量硫氮分析仪、氮化学发光气相色谱仪(GC-NCD)、电喷雾电离(ESI)傅里叶变换离子回旋共振质谱(FT-ICR MS)和X射线光电子能谱(XPS)对液化油及残渣中的含氮化合物进行分子识别表征。结果表明,原煤中含量较多的季氮,在液化条件下转化为NH3,迁移到气相产物中,液化残渣中以稠环形态的吡啶氮和吡咯氮为主。氮在气体、低分油、高分油、残渣的比例分别为35.21%、24.41%、19.79%、20.59%。小于170℃液化油馏分含氮化合物含量由高到低排序为:苯胺类>吲哚类>喹啉类>脂肪胺类。大于170℃液化油馏分含氮化合物从N_(1)到N_(X)O_(X)(X=1-2)均存在,主要是苯并咔唑带环烷侧链和苯并咔唑带环烷醚链两类含氮化合物。

In the hydroliquefaction process of coal,the nitrogenous compounds conversion behavior were researched,as well as the occurrence form in gas,liquid and solid three-phase products.The research can provided theoretical basis for efficient and clean utilization of low-rank coal.The continuous hydroliquefaction test of Xinjiang Baishihu coal was carried out using 0.01t/d continuous test device.The sulfur and nitrogen detector,GC-NCD,ESI FT-ICR MS and XPS were used to identify and characterize the nitrogen compounds in liquefied oil and residue.The results show that the quaternary nitrogen in the raw coal can be transformed into NH3 and migrated to the gaseous products under liquefaction condition,the residue is dominated by pyridine nitrogen and pyrrole nitrogen in the form of thick ring.The proportion of nitrogen in gas,low fraction oil,high fraction oil and residue are 35.21%,24.41%,19.79%and 20.59%respectively.Nitrogenous compounds in liquefied oil fraction below 170℃are aniline>indole>quinoline>fatty amines from high to low.Nitrogen compounds exist from N_(1) to N_(x)O_(x) in liquefied oil fractions above 170℃,the main nitrogenous compounds are benzocarbazole with naphthenic side chain and benzocarbazole with naphthenic ether chain.