Probing Dynamics and Interaction of Maltenes with Asphaltene Aggregates in Crude Oils by Multiscale NMR
Probing Dynamics and Interaction of Maltenes with Asphaltene Aggregates in Crude Oils by Multiscale NMR
复制标题
通过多尺度核磁共振探测原油中马质烯与沥青质聚集体的动力学和相互作用
DOI：
10.1021/acs.energyfuels.5b01142
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
J. Korb
中科院分区：
文献类型：
--
作者：
Nopparat Vorapalawut;B. Nicot;A. Louis;J. Korb
沥青质在原油运输、炼油和生产中造成许多问题。因此，清楚地了解原油中沥青质的行为对于提高原油产量至关重要。在这里，我们使用了非侵入性的多尺度核磁共振技术，如低场核磁共振2D D-T2、T1-T2、核磁弛豫色散(NMRD)技术以及高场二维(2D)核磁共振剂量，以探索原油中马来烯类与沥青质聚集体的动力学和相互作用。通过使用稀释过程来保持天然原油中最初存在的沥青质聚集体结构，我们制备了不同的沥青质浓度，范围从0wt%(纯马来烯)到9wt%(天然原油)。我们用多尺度核磁共振技术表明，沥青质浓度的变化会导致烃类动力学的剧烈变化。在天然原油中，观察到扩散系数(D)与横向弛豫时间(T2)之间的反常关系，从而可以再现理论。
Asphaltenes cause many problems in crude oil transportation, refinery, and production. A clear understanding of asphaltene behavior in crude oils is thus crucial for improving crude oil production. Here, we used noninvasive multiscale NMR techniques such as low field NMR 2D D–T2, T1–T2, nuclear magnetic relaxation dispersion (NMRD) techniques as well as high field two-dimensional (2D) NMR DOSY for probing the dynamics and interaction of maltenes with asphaltene aggregates in crude oil. We prepared different asphaltene concentrations ranging between 0 wt % (pure maltenes) and 9 wt % (native crude oil) by using a dilution procedure that maintains the asphaltene aggregates structure initially present in native crude oil. We showed by multiscale NMR techniques that changing asphaltene concentration induces a drastic modification of hydrocarbon dynamics. In native crude oil, we observe anomalous relation between the diffusion coefficient (D) and the transverse relaxation time (T2) that we can reproduce theoret...