Department of Environment and Energy, Sejong University , Seoul 143-747, South Korea.
Environ Sci Technol. 2013 Sep 17;47(18):10541-7. doi: 10.1021/es402250g. Epub 2013 Sep 5.
Using biomass as a renewable energy source via currently available thermochemical processes (i.e., pyrolysis and gasification) is environmentally advantageous owing to its intrinsic carbon neutrality. Developing methodologies to enhance the thermal efficiency of these proven technologies is therefore imperative. This study aimed to investigate the use of CO2 as a reaction medium to increase not only thermal efficiency but also environmental benefit. The influence of CO2 on thermochemical processes at a fundamental level was experimentally validated with the main constituents of biomass (i.e., cellulose and xylan) to avoid complexities arising from the heterogeneous matrix of biomass. For instance, gaseous products including H2, CH4, and CO were substantially enhanced in the presence of CO2 because CO2 expedited thermal cracking behavior (i.e., 200-1000%). This behavior was then universally observed in our case study with real biomass (i.e., corn stover) during pyrolysis and steam gasification. However, further study is urgently needed to optimize these experimental findings.
利用生物质作为一种可再生能源，通过目前可用的热化学工艺（即热解和气化），由于其内在的碳中性，在环境方面具有优势。因此，开发方法来提高这些成熟技术的热效率是至关重要的。本研究旨在探讨使用 CO2 作为反应介质，不仅提高热效率，而且提高环境效益。通过实验验证了 CO2 对生物质主要成分（即纤维素和木聚糖）的热化学过程的基础影响，以避免因生物质不均匀基质而产生的复杂性。例如，在 CO2 的存在下，H2、CH4 和 CO 等气体产物显著增加，因为 CO2 加速了热裂解行为（即 200-1000%）。在我们的案例研究中，这种行为在热解和蒸汽气化过程中普遍存在于真正的生物质（即玉米秸秆）中。然而，迫切需要进一步研究来优化这些实验结果。
