油溶性降黏剂降黏降凝作用机理的理论与实验研究  

Theoretical and Experimental Research on the Action Mechanism for Lowering Viscosity and Pour Point by Oil-Soluable Viscosity Reducer

作　　者：王大喜[1] 郭磊[1] 王亮[1] 刘益华[1] 王瑜[1] 

机构地区：[1]中国石油大学(北京)重质油加工国家重点实验室,北京102249

出　　处：《油田化学》2010年第3期314-319,共6页Oilfield Chemistry

摘　　要：采用量子化学密度泛函方法全优化计算了沥青质模型化合物I及其双层结构ID的几何结构,设计了一种带强亲水磺酸基团的降黏剂,计算研究了其降黏降凝作用机理。双层沥青质结构分子间的层间距在0.4097~0.4258 nm范围,计算结果与实验测定值（0.3570~0.3590 nm）相近;分子间作用能为-67.6 kJ/mol。计算发现设计的降黏剂可与沥青质形成强分子间氢键,破坏了沥青质分子间的氢键,分离了沥青质的层状结构,预示设计的降黏剂可起到降黏作用。计算还发现降黏剂的烷基部分可与沥青质的烷基共晶,阻止沥青质似晶结构的有序生长,预示该降黏剂还可起到降凝作用。用自制的降黏剂测试降黏降凝性能发现,降黏剂浓度为1000 mg/L时,80℃下稠油的降黏率达84.62%;同样浓度下稠油凝点从32℃降至4℃。实验结果很好地考证了理论分析的降黏降凝机理。The geometries of asphaltene model compound I and its double layer structure ID were calculated by the quantum chemical method on the density function theory（DFT）.The viscosity reducer with sulfo group had been designed and the action mechanisms for lowering viscosity and pour point by it were studied.The distance of double layer structure ID calculated ranged from 0.4097 nm to 0.4258 nm,which was close to the measurements 0.3570-0.3590 nm.Interaction energy of intermolecular calculated was-67.6 kJ/mol.It was found by the calculation that the strong hydrogen bonds between viscosity reducer and asphaltene molecules formed.At the same time,the hydrogen bonds between asphaltene molecules were destroyed.The viscosity reducer could separate the lamellar structure of asphaltene molecules,and the viscosity-reducing effect was indicated.In addition,eutectic structure between alkyl of viscosity reducer and alkyl of asphaltene formed,which resulted in disorder of crystal grow for asphaltene,and pour point depressing effect was shown.The results of lowering viscosity and pour point by the viscosity reducer showed that the viscosity-reducing ratio reached 84.62% at 80℃ when 1000 mg/L viscosity reducer added into the vicious crude oil.Under the same concentration,the pour point reduced from 32℃ to 4℃.The experiments validated the action mechanism of lowering viscosity and pour point in theory excellently.

关 键 词：量子化学 密度泛函方法 降黏 降凝 作用机理 

分 类 号：O641[理学—物理化学]