College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Department of Civil, Environmental and Geomatic Engineering, University College London, Gower Street, London WC1E 6BT, UK.
Shanghai Shendi Institute, Shanghai 200120, China.
Bioresour Technol. 2018 Jul;259:91-98. doi: 10.1016/j.biortech.2018.03.010. Epub 2018 Mar 6.
The process characteristics of microwave assisted hydrothermal carbonization of cellulose was investigated and a first order kinetics model based on carbon concentration was developed. Chemical properties analysis showed that comparing to conventional hydrothermal carbonization, hydrochar with comparable energy properties can be obtained with 5-10 times decrease in reaction time with assistance of microwave heating. Results from kinetics study was in great agreement with experimental analysis, that they both illustrated the predominant mechanism of the reaction depend on variations in the reaction rates of two co-existent pathways. Particularly, the pyrolysis-like intramolecular dehydration reaction was proved to be the predominant mechanism for hydrochar generation under high temperatures. Finally, the enhancement effects of microwave heating were reflected under both soluble and solid pathways in this research, suggesting microwave-assisted hydrothermal carbonization as a more attracting method for carbon-enriched hydrochar recovery.
研究了微波辅助纤维素水热碳化的过程特性，并建立了基于碳浓度的一级动力学模型。化学性质分析表明，与传统水热碳化相比，在微波加热的辅助下，反应时间可减少 5-10 倍，即可获得具有可比能量特性的水炭。动力学研究的结果与实验分析非常吻合，它们都表明反应的主要机制取决于两个共存途径的反应速率的变化。特别是，在高温下，证明了类似于热解的分子内脱水反应是生成水炭的主要机制。最后，本研究反映了在可溶性和固态两种途径下微波加热的增强效果，表明微波辅助水热碳化是一种更有吸引力的富碳水炭回收方法。
