磷酸锆辅助催化水解菌糠制备纳米纤维素晶体的性能

以食用菌产业的副产品菌糠为原料,采用磷酸锆催化剂辅助稀硫酸水解制备纳米纤维素晶体(cellulose nanocrystals,CNCs).与传统酸水解方法相比,该方法简化了工艺流程,制备过程环境友好。考察了超声时间、超声温度以及稀硫酸浓度等因素对CNCs得率的影响。结果表明当超声时间为5h、超声温度为75℃及稀硫酸浓度为12.3%时,CNCs得率为42.80%.采用透射电子显微镜(TEM)、扫描电子显微镜(SEM)、傅里叶变换红外光谱(FTIR)以及X射线衍射仪(XRD)对样品的微观形貌、谱学性能和晶体结构进行了研究分析,结果表明所制得的CNCs呈棒状,直径介于10～30nm之间;CNCs属于纤维素I型,与原料菌糠相比,结晶度由63.79%增大到81.04%;且CNCs仍具有天然纤维素的基本化学结构。论文研究为菌糠的资源化高效利用开辟了新途径。

Preparation of cellulose nanocrystals by solid catalyst zirconium phosphate assisted hydrolysis from spent mushroom substrate

In this research,cellulose nanocrystals (CNCs) were prepared by solid catalyst zirconium phosphate assisted hydrolysis method from spent mushroom substrate. Compared with traditional acid hydrolysis method,this method is simpler to operate and more eco-friendly. The effect of ultrasonication time,ultrasonication temperature and the concentration of diluted sulfuric acid on the yield of CNCs were investigated. The results showed that the yield of CNCs reached 42.80%,when ultrasonication time was 5h,ultrasonication temperature was 75℃ and the concentration of diluted sulfuric acid was 12.3%. The microstructure,morphology,spectrum properties and the crystal structure of CNCs were characterized by transmission electron microscopy(TEM),scanning electron microscope (SEM),fourier transformation infrared spectroscopy (FTIR) and X-ray diffraction (XRD),respectively. The SEM and TEM showed that CNCs were rod-like with diameters of 10-30nm,and the FTIR analysis showed that the CNCs still kept the basic chemical structure of cellulose. The XRD pattern showed that the CNCs presented the crystal form of cellulose I. Compared with the spent mushroom substrate,the crystallinity of CNCs increased from 63.79% to 81.04%. This research proposed a new approach to efficient utilization of the spent mushroom substrate.