大麻纤维超临界CO_(2)脱胶工艺

Degumming process for hemp fibers in supercritical CO_(2)

为解决大麻纤维脱胶效果差和水资源短缺等问题,采用超临界CO_(2)代替水对大麻纤维进行脱胶,并探讨了脱胶温度、脱胶压力、脱胶时间和CO_(2)流量对大麻纤维残胶率和果胶含量的影响。采用扫描电镜(SEM)对脱胶前后纤维的表面形貌进行分析。大麻纤维较优的脱胶工艺条件为:脱胶温度100℃、脱胶压力24 MPa、脱胶时间90 min、CO_(2)流量30 g/min。在此条件下,脱胶后大麻纤维的残胶率和果胶含量分别降低到31.6%、11.47%。脱胶后的纤维表面比较光滑,纤维变细,并且部分纤维表面有裂纹。

In order to solve the problems of poor degumming effect and water shortage for hemp fiber in degumming process,an anhydrous degumming technology for hemp fibers using supercritical CO_(2) instead of water is proposed.The effects of degumming temperature,degumming pressure,degumming time,and a CO_(2) flow on residual gum content and pectin content of hemp fibers are systematically studied in supercritical CO_(2) fluid.The surface morphology of hemp fibers is analyzed by employing scanning electron microscopy(SEM)before and after degumming.The optimal conditions for degumming process of hemp fibers is that the degumming temperature is 100℃,the degumming pressure is 24 MPa,the degumming time is 90 min and the CO_(2) flow in supercritical CO_(2) is 30 g/min.Under these conditions,residual gum content and pectin content of hemp fibers can be reduced to 31.6%and 11.47%,respectively.After degumming,the surface of the fiber is smooth,the fiber becomes thinner,and some of the fiber surface has cracks.