桦甸油页岩热解过程中热沥青的组成变化规律  

Variation of chemical composition of thermal bitumen during Huadian oil shale pyrolysis

作　　者：畅志兵[1] 初茉[1] 张超[1] 白书霞[1] 林浩[1] 

机构地区：[1]中国矿业大学(北京)化学与环境工程学院,北京100083

出　　处：《燃料化学学报》2016年第11期1310-1317,共8页Journal of Fuel Chemistry and Technology

基　　金：国家重点基础研究发展规划(973计划;2014CB744301)资助~~

摘　　要：将桦甸油页岩分别在300、350、400、450、500和550℃热解得到半焦,对半焦进行逐级抽提和酸洗,得到自由沥青、碳酸盐束缚沥青和硅酸盐束缚沥青,采用柱层析、FT-IR和GC-MS表征不同沥青的化学组成和结构特征,探讨沥青的化学组成变化及与矿物质的相互作用。结果表明,沥青总产率先增大后减小并在400℃取得最大值4.63%,400-450℃大量沥青分解生成页岩油,使沥青产率降至0.98%。350-450℃自由沥青主要发生羧酸脱羧、酯基分解和长链烷烃裂解反应,使羧酸和酯类化合物含量降低、烷烃碳链长度缩短。干酪根分解生成的羧酸与碳酸盐反应生成羧酸盐,使400℃碳酸盐束缚沥青中羧酸含量达78.82%;含氧化合物可与黏土矿物结合,且烷烃可进入蒙脱石层间,使400℃硅酸盐束缚沥青中含氧化合物和烷烃各占80.79%和19.21%。The variation of chemical composition of thermal bitumen during Huadian oil shale pyrolysis was studied. Spent shale samples obtained by retorting oil shale at 300-550 ℃ were subjected to sequential Soxhlet extraction-acid pickling-Soxhlet extraction procedures to obtain free bitumen(FB), bitumen bound with carbonates(BB-1) and bitumen bound with silicates(BB-2). The bitumen samples were characterized by liquid chromatography fractionation,FT-IR and GC-MS. The results show that the total bitumen yield first increases and then decreases with increasing temperature from 300 to 550 ℃,and reached the maximum value of 4.63% at400 ℃. Especially,the intense vaporization and decomposition of bitumen occurring at 400- 450 ℃ causes a dramatic decrease in bitumen yield from 4.63% to 0.98%. Decarboxylation of aliphatic acids,decomposition of esters and cracking of long-chain alkanes take place at 350-450 ℃,which decreases the contents of acids and esters in FB and shortens the chain length of alkanes. The carboxylic acids derived from kerogen pyrolysis can react with carbonates to form carboxylates,leading to a high amount of aliphatic acids in 400 ℃ BB-1(78.82%). The contents of oxygenated compounds(acids,esters and phenols) and alkanes of 400 ℃ BB-2 are80.79% and 19.21%,respectively,due to the combination between oxygenated compounds and clay minerals,and the insertion of alkanes into the interlayer space of montmorillonite.

关 键 词：油页岩 热解 热沥青 化学组成 

分 类 号：TQ534[化学工程—煤化学工程]