Department of Engineering Mechanics, Zhejiang University, 310027 Hangzhou, China.
Department of Engineering Mechanics, Zhejiang University, 310027 Hangzhou, China; State Key Laboratory of Clean Energy Utilization, Zhejiang University, 310027 Hangzhou, China.
Bioresour Technol. 2020 Dec;317:124007. doi: 10.1016/j.biortech.2020.124007. Epub 2020 Aug 12.
Microalgae Spirulina has good potential for bio-oil production. Therefore, kinetic and thermodynamic analysis of its pyrolysis process was performed. The activation energy values were estimated using both differential (109-340 kJ/mol) and integral (102-272 kJ/mol) isoconversional methods. Kinetic model was determined using master plot approach and the pyrolysis reaction appeared to transition between nucleation, diffusion and order-based kinetic models. Based on sigmoidal equations, a novel kinetic model equation was proposed which can define the pyrolysis process of algal biomass showing single differential thermogravimetric peak. The proposed kinetic triplet predicted the weight loss evolution quite precisely. Additionally, the thermodynamic feasibility of the reaction was examined based on enthalpy, entropy and Gibbs free energy. It was revealed that heat is consumed to make the raw sample reach a 'more orderly' state until a fractional conversion of 0.35. Moreover, bio-char and the remaining lipids at high temperature impede the reaction spontaneity towards the end.
微藻螺旋藻具有很好的生物油生产潜力。因此，对其热解过程进行了动力学和热力学分析。使用差示（109-340 kJ/mol）和积分（102-272 kJ/mol）等转化率方法估算了活化能值。使用主图法确定了动力学模型，并且热解反应似乎在成核、扩散和基于顺序的动力学模型之间转变。基于正弦方程，提出了一种新的动力学模型方程，该方程可以定义显示单个差示热重峰的藻类生物质的热解过程。所提出的动力学三参数集非常精确地预测了失重演化。此外，还根据焓、熵和吉布斯自由能检验了反应的热力学可行性。结果表明，热量被消耗以使原始样品达到“更有序”的状态，直到转化率为 0.35。此外，在高温下的生物炭和剩余脂质阻碍了反应向结束时的自发性。
