Gold-tube pyrolysis experiments were performed on two Athabasca oil sand bitumens at 300 °C to 525 °C with 2 °C/h rate and 25 °C step under 50 MPa. Pyrolysis temperature of 425 °C is critical for weight loss of bulk bitumen and hydrocarbon generation and destruction. Polar compounds are the main source of saturated and aromatic hydrocarbon, gas and coke fractions. Molecular compositions in pyrolyzates vary systematically with increasing pyrolysis temperatures. High molecular weight n-alkanes (C₂₆⁺) are gradually destructed during pyrolysis due to thermal cracking. Moderate molecular weight n-alkanes (C₂₁–C₂₅) show the highest thermal stability in designed pyrolysis temperatures. The loss of low molecular weight n-alkanes (C₂₀⁻) might be caused by volatilization during pyrolysis, which may alter commonly used molecular parameters such as ∑n-C₂₀⁻/∑n-C₂₁⁺, Pr/n-C₁₇ and Ph/n-C₁₈. Aromatic hydrocarbons were generated from 300 to 425 °C, then condensation and dealkylation have been initiated at 425 °C as evidenced by decreased summed alkylnaphthalenes to alkylphenanthrenes ratios and increased unsubstituted aromatics to substituted homologs ratios in higher temperatures. The occurrence of anthracene and benz[a]anthracene in pyrolysates indicates pyrogenic origin, while fluoranthene shows unexpected behaviors during pyrolysis. Ratios derived from them are not always reliable for pyrogenic source input diagnosis in environmental samples.

金管热解实验是在两个Athabasca油砂沥青上以300°C至525°C的速度以2°C / h的速率和25°C的压力在50 MPa下进行的。425°C的热解温度对于大量沥青的重量损失以及碳氢化合物的产生和破坏至关重要。极性化合物是饱和和芳香烃，气体和焦炭馏分的主要来源。热解产物中的分子组成随热解温度的升高而系统地变化。在热解过程中，由于热裂解，高分子量正构烷烃（C ₂₆ ⁺）逐渐被破坏。中等分子量的正构烷烃（C ₂₁ –C ₂₅）在设计的热解温度下显示出最高的热稳定性。低分子量的损失ñ -烷烃（C ₂₀ ^- ）可以通过热解过程中挥发，这可能会改变通常使用的分子参数，如Σ引起Ñ -C ₂₀ ^- /Σ Ñ -C ₂₁ ⁺，镨/ Ñ -C ₁₇和Ph / n -C ₁₈。在300至425°C的温度下生成芳烃，然后在425°C的温度下开始缩合和脱烷基，这是由较高温度下烷基萘与烷基菲的总和降低和未取代芳族化合物与取代同系物之比增加所证明的。在热解物中蒽和苯并[a]蒽的存在表明热解的起源，而荧蒽在热解过程中表现出出乎意料的行为。从它们得出的比率对于环境样品中的热源输入诊断并不总是可靠的。