纤维素热解过程中活性纤维素的生成研究

热重分析发现活性纤维素的生成始于530 K左右,对应于失重图上的肩部及SDTA曲线中强烈的放热峰.在辐射加热闪速热裂解试验台上获取了一种可溶于水、高温下易分解、室温下呈固态且稳定存在的黄色中间产物.扫描电镜图片证明在热裂解初期纤维素经历了一个熔化和相互粘结的状态,产物的红外谱图证实了大量的羰基和羧基官能团的生成.高效液相色谱分析证明其主要成分是一系列聚合度不同的低聚糖,推断该低聚糖即为活性纤维素.

STUDY ON FORMATION OF ACTIVE CELLULOSE IN PYROLYSIS PROCESS

This paper presents the thermogravimetric analysis of cellulose pyrolysis.It is shown that the formation of active cellulose starts at the temperature of about 530 K,corresponding to the shoulder in weight loss curve and the intensive exothermic peak in Simultaneous Differential Thermal Analysis (SDTA)curve.An intermediate product that is yellow,soluble and solid at ambient temperature and liable to decompose at even high temperature,is generated in a high radiation flash pyrolysis reactor.Scanning Electron Microscope(SEM)pictures indicate that the melting and bonding of cellulose particles take place in the initial pyrolysis stage.Large amount of carbonyl and carboxyl groups are formed as shown in the Infra-red(IR)spectra.High Performance Liquid Chromatogram (HPLC)analysis illustrates the main existence of oligosaccharides with different polymerization degree, expected to be active cellulose.