采用核磁共振方法表征重质油结构

采用700 MHz高场核磁谱仪建立了由核磁共振波谱(NMR)获取重质油H、C原子分布与结构参数的分子结构表征方法。以减压馏分油(VGO)和减压渣油(VR)为研究对象，对13C NMR实验条件进行优化， 并考察了1H NMR 和13C NMR实验重复性和准确性。结果表明，较优的13C NMR实验条件是样品质量分数为100%、30°脉冲倾倒角下的延迟时间为50 s；1H NMR和13C NMR实验的6次重复实验的实验标准差分别为086%、136%，1H NMR和13C NMR实验测定重质油中H、C原子分布的准确性误差均在±10%以内。

Analysis for Chemical Structure of Heavy Crude Oil by NMR

700 MHz NMR was used to analyze the molecular structure, such as C, H atom distribution and relative structure parameters, of heavy crude oil. The experimental conditions of 13C NMR were optimized with VGO and vacuum residue(VR) as samples，and also repeatability and accuracy of 1H NMR and 13C NMR were investigated. The results showed that appropriate sample mass fraction was 100% and delay time was 50 s under 30° pulse angle in 13C NMR experiment. Experimental standard deviation of six repeated experiments of 1H NMR and 13C NMR were 086% and 136%，respectively. The accuracy of 1H NMR and 13C NMR analysis method characterizing hydrogen and carbon types in heavy crude oil were both within ±10%. 