摘要
为了阐明在双亲性催化剂的条件下,在250℃和280℃下稠油水热裂解反应对稠油沥青质分子结构及稠油黏度的影响,以胜利稠油为研究对象,使用C_(12)BSNi为催化剂,通过使用FT-IR和~1HNMR等手段分析水热裂解反应前后沥青质分子结构的变化。研究结果表明,稠油在250℃下发生水热裂解反应后,黏度大幅降低,降黏率可达到60.4%,但随着反应温度升高到280℃时,反应后的降黏率降至53.8%。随水热裂解反应温度从250℃升高到280℃,稠油沥青质分子平均侧链长度逐渐减小,然而芳香度不断增加,芳环数量增多,说明沥青质分子发生了自由基缩合反应,沥青质平均分子结构变大,导致降黏率相对减小;此外,沥青质分子在反应过程中发生一系列的断键反应,导致其空间位阻减小,且沥青质分子单元片层越小越容易发生堆积。通过SEM观察到,随温度升高,沥青质的孔道逐渐变大并且更加密集,但表面聚集颗粒变大。本文研究对稠油水热裂解反应操作条件的优化有重要的指导意义。
In order to clarify the effect of heavy oil hydrothermal cracking temperature at 250℃and 280℃on the molecular structure of asphaltene and the viscosity of heavy oil under the catalysis of amphiphilic catalyst,taking Shengli heavy oil as the research object and C_(12)BSNi as the catalyst,the changes of asphaltene molecular structure before and after the reaction were analyzed by FTIR and 1H-NMR.The results showed that when the hydrocracking reaction of heavy oil occurred at the temperature of 250℃,the viscosity of heavy oil was greatly reduced,the viscosity reduction rate being of 60.4%,while the viscosity reduction rate decreased with the increase of reaction temperature to 280℃,viscosity reduction rate only being of 53.8%.As the reaction temperature increased from 250℃to 280℃,the average side chain length of asphaltene molecules gradually decreased,but the aromaticity increased and the number of aromatic rings increased,which indicated that asphaltene molecules had undergone radical condensation reactions,and the average molecular structure of asphaltene became larger,resulting in a relatively small viscosity reduction rate.In addition,a series of bond breaking reactions occurred during the reaction of asphaltene molecules,resulting in the reduction of their steric hindrance.The smaller the asphaltene molecular unit lamella,the easier it was to accumulate.It was observed by SEM that the pore channel of asphaltene structure gradually became larger and denser with the increase of temperature,but the surface aggregated particles became larger.It provided important guiding significance for the optimization of operating conditions of heavy oil hydrothermal cracking reaction.
作者
张玉
初伟
张龙力
曹嫣镔
王继乾
ZHANG Yu;CHUWei;ZHANG Longli;CAO Yanbin;WANG Jiqian(School of Chemistry and Chemical Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,P R of China;Research Institute of Petroleum Engineering Technology,Shengli Oilfield Branch Company,Sinopec,Dongying,Shandong 257000,P R of China)
出处
《油田化学》
CAS
CSCD
北大核心
2023年第1期93-101,共9页
Oilfield Chemistry
基金
国家自然科学基金面上项目“重质油沥青质缔合行为及介尺度行为的电学响应研究”(项目编号21576292)。
关键词
稠油
催化剂
水热裂解反应
沥青质
分子结构
heavy oil
catalyst
hydrothermal cracking reaction
asphaltene
molecular structure
