School of Material Science and Engineering, University of Jinan, Jinan, 250022, PR China.
Joint International Research Laboratory of Biomass Energy and Materials, College of Materials Science and Engineering, Nanjing Forestry University, Nanjing, 210037, PR China.
Chemosphere. 2023 Sep;336:139248. doi: 10.1016/j.chemosphere.2023.139248. Epub 2023 Jun 15.
The interaction between volatiles and homologous and/or heterologous char is almost inevitable during the transfer or diffusion of volatiles from inner core to outer surface of a biomass particle in pyrolysis. This shapes both composition of volatiles (bio-oil) and property of char. In this study, the potential interaction of lignin- and cellulose-derived volatiles with char of varied origin was investigated at 500 °C. The results indicated that both the lignin- and cellulose-char promoted polymerization of the lignin-derived phenolics, enhancing production of bio-oil by ca. 20%-30%, generating more heavy tar but suppressing gases formation, especially over cellulose-char. Conversely, the char catalysts, especially the heterologous lignin-char, promoted cracking of the cellulose-derivatives, producing more gases while less bio-oil and heavy organics. Additionally, the volatiles-char interaction also led to gasification of some organics and also aromatization of some organics on surface of char, resulting in enhanced crystallinity and thermostability of the used char catalyst, especially for the lignin-char. Moreover, the substance exchange and formation of carbon deposit also blocked pores and formed fragmented surface dotted with particulate matters in the used char catalysts.
在生物质颗粒热解过程中，挥发性物质从内部核心向外部表面传递或扩散时，挥发性物质与同源和/或异源焦之间的相互作用几乎是不可避免的。这会影响挥发性物质（生物油）的组成和焦的性质。在这项研究中，在 500°C 下研究了不同来源的木质素和纤维素衍生的挥发性物质与焦之间的潜在相互作用。结果表明，木质素和纤维素焦都促进了木质素衍生酚类的聚合，使生物油的产量增加了约 20%-30%，生成了更多的重焦油，但抑制了气体的形成，特别是在纤维素焦上。相反，焦催化剂，特别是异源木质素焦，促进了纤维素衍生物的裂解，产生了更多的气体，而生物油和重有机物质较少。此外，挥发性物质与焦之间的相互作用还导致一些有机物质的气化和焦表面上一些有机物质的芳构化，从而提高了使用过的焦催化剂的结晶度和热稳定性，特别是对木质素焦而言。此外，物质交换和积碳的形成也会堵塞孔，并在使用过的焦催化剂表面形成带有颗粒物质的碎片状表面。
