Understanding the Liquid-Liquid Equilibrium (LLE) of multicomponent solvent/bitumen systems is pivotal in optimizing in-situ bitumen extraction. While Vapor-Liquid Equilibria (VLE) of solvent-bitumen systems has been extensively studied, LLE data and predictive models for these mixtures, especially those involving synthetic multicomponent solvents, are scarce. This study provides comprehensive LLE measurements of bitumen and a multicomponent synthetic solvent (n-pentane + n-hexane + n-heptane + -hexane + toluene) conducted under controlled equilibrium conditions at temperatures of 295 to 352 K, solvent concentrations up to 70 wt% at 1.291 MPa. Application of common correlation used in the construction of solvent-aided process fluid models exhibited average absolute relative deviations (AARDs) of 0.37 % for density and 8.87 % for viscosity. We identified the boundaries marking the shift from homogenous single-phase liquid to two-phase (LLE) states, which occurs within the synthetic multicomponent solvent concentration range of 50 to 60 wt%. We also successfully constructed calibration curves to measure solvent concentrations in both phase regions. The molecular weight distribution and saturates, aromatics, resins, and asphaltene (SARA) fractionation of both liquid phases were determined, highlighting that the heavy liquid phase is primarily asphaltene (∼46 wt%). The insights gained from the measurements and analysis find applications in designing and optimizing solvent-assisted thermal recovery processes for bitumen extraction.

中文翻译：

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合成多组分溶剂（正戊烷、正己烷、正庚烷、环己烷、甲苯）/沥青系统的液-液平衡测量分析：对溶剂辅助原位沥青萃取的影响

了解多组分溶剂/沥青系统的液液平衡 (LLE) 对于优化原位沥青提取至关重要。虽然溶剂-沥青系统的气液平衡 (VLE) 已被广泛研究，但这些混合物（尤其是涉及合成多组分溶剂的混合物）的 LLE 数据和预测模型却很少。本研究提供了沥青和多组分合成溶剂（正戊烷 + 正己烷 + 正庚烷 + 正己烷 + 甲苯）的全面 LLE 测量，在受控平衡条件下、温度为 295 至 352 K、溶剂浓度高达 70 wt % 在 1.291 MPa 下。在溶剂辅助过程流体模型构建中使用的常见相关性的应用显示，密度的平均绝对相对偏差 (AARD) 为 0.37%，粘度的平均绝对相对偏差 (AARD) 为 8.87%。我们确定了标志着从均质单相液体到两相 (LLE) 状态转变的边界，这种转变发生在 50 至 60 wt% 的合成多组分溶剂浓度范围内。我们还成功构建了校准曲线来测量两个相区的溶剂浓度。测定了两个液相的分子量分布和饱和物、芳烃、树脂和沥青质 (SARA) 分馏，突出表明重液相主要是沥青质 (~46 wt%)。从测量和分析中获得的见解可用于设计和优化沥青提取的溶剂辅助热回收工艺。