Forest Products Development Center, School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL 36849, USA.
Bioresour Technol. 2013 Apr;133:1-8. doi: 10.1016/j.biortech.2013.01.108. Epub 2013 Jan 30.
The goal of this study was to characterize the changes in biomass with torrefaction for near infrared reflectance (NIR) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy for sweetgum, loblolly pine, and switchgrass. Calibration models were built for the prediction of proximate analysis after torrefaction. Two dimensional (2D) correlation spectroscopy between NIR and FTIR was found to precisely explain the depolymerization at key functional groups located within hemicellulose, cellulose, and lignin. This novel 2D technique also demonstrated the possibility of assigning key NIR wavenumbers based on mid IR spectra. Hemicellulose based wavenumbers were found to be most sensitive to torrefaction severity with complete degradation at 250-275°C. Lignin associated wavenumbers exhibited the least degradation to severity but was still detected with 2D correlation spectroscopy. Finally, calibration models for proximate analysis were performed and while both systems could be used for rapid monitoring, NIR performed better than FTIR.
本研究的目的是为了表征近红外反射光谱（NIR）和衰减全反射傅里叶变换红外光谱（ATR-FTIR）分析中热解过程中生物质的变化，用于枫香、火炬松和柳枝稷。建立了预测热解后常规分析的校正模型。NIR 和 FTIR 之间的二维相关光谱被发现可以精确地解释位于半纤维素、纤维素和木质素内关键官能团的解聚。这项新颖的二维技术还展示了根据中红外光谱分配关键近红外波数的可能性。基于半纤维素的波数对热解程度最敏感，在 250-275°C 时完全降解。与严重程度相比，木质素相关的波数降解最少，但仍可通过二维相关光谱检测到。最后，进行了常规分析的校正模型，尽管两种系统都可用于快速监测，但 NIR 的性能优于 FTIR。
