After extraction of high-added value components of Spirulina sp., the remaining residues can be valorized by hydrothermal liquefaction to produce an oily water insoluble viscous phase (biocrude) which is very similar to petroleum bitumen. This hydrophobic fraction is composed of various N-,O-containing cyclic compounds, fatty acids, amides, nitriles, alkenes and alkanes. In order to optimize the rheological properties of the biocrude, we studied the addition of different catalysts with various loadings: ZrO₂ or CeO₂, or Ce(NO₃)₃.6H₂O as well as the effect of residence time during HTL. The biocrude has been systematically characterized by GCxGC, GPC, elemental analyses and dynamic shear rheology and compared to a petroleum bitumen. The different catalysts tested had little influence on the composition of the HTL hydrophobic fraction in the chosen operating conditions. In contrast, increasing the reaction time (from 1 to 7 h) was found to promote condensation reactions, thereby increasing the average molecular weight of the biocrude, leading to a viscoelastic material very similar to a petroleum bitumen.

提取螺旋藻的高附加值成分后，剩余的残留物可以通过水热液化进行增值，以产生与石油沥青非常相似的油性水不溶性粘性相（生物原油）。这种疏水部分由各种含 N、O 的环状化合物、脂肪酸、酰胺、腈、烯烃和烷烃组成。为了优化生物原油的流变性能，我们研究了添加不同负载量的不同催化剂：ZrO ₂或 CeO ₂或 Ce(NO ₃ ) ₃ .6H ₂O 以及 HTL 期间停留时间的影响。生物原油已通过 GCxGC、GPC、元素分析和动态剪切流变学进行了系统表征，并与石油沥青进行了比较。在选定的操作条件下，测试的不同催化剂对 HTL 疏水部分的组成几乎没有影响。相比之下，发现增加反应时间（从 1 小时到 7 小时）会促进缩合反应，从而增加生物原油的平均分子量，从而产生与石油沥青非常相似的粘弹性材料。