Millisecond Pulsed Films Unify the Mechanisms of Cellulose Fragmentation [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 621.47 Solar-energy engineering
• Thông tin xuất bản: Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Science ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2016
• Mô tả vật lý: Size: p. 3108-3114 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 263498
• Chủ đề: 1. 09 biomass fuels; 2. Cellulose; 3. Kinetics; 4. Organic reactions; 5. Reaction rates

Tóm tắt

 The mechanism of crystalline cellulose fragmentation has been debated between classical models proposing end-chain or intrachain scission to form short-chain (molten) anhydro-oligomer mixtures and volatile organic compounds. Models developed over the last few decades suggest global kinetics consistent with either mechanism, but validation of the chain-scission mechanism via measured reaction rates of cellulose has remained elusive. To resolve these differences, we introduce a new thermal-pulsing reactor four orders of magnitude faster than conventional thermogravimetic analysis (10<
 sup>
 6<
 /sup>
  vs 10<
 sup>
 2<
 /sup>
  �C/min) to measure the millisecond-resolved evolution of cellulose and its volatile products at 400?550 �C. By comparison of cellulose conversion and furan product formation kinetics, both mechanisms are shown to occur with the transition from chain-end scission to intrachain scission above 467 �C concurrent with liquid formation comprised of short-chain cellulose fragments.