Preparation of microcrystalline cellulose from Rabdosia rubescens and study on its membrane properties
Abstract Microcrystalline cellulose (MCC) from Rabdosia rubescens was prepared by acid hydrolysis, and the corresponding yield of MCC was about 94% when the hydrochloric acid concentration was 10%, the acid hydrolysis time was 70min and the acid hydrolysis temperature was 70℃. The MCC was dissolved in N-methylmorpholine-N-oxide(NMMO)by phase transformation method to prepare MCC membrane. The structure and mechanical properties of MCC membrane were studied systemically. The results showed that the cellulose structure changed from type I to type II in the process of membrane formation, and the thermal stability also decreased. The content of MCC in the casting solution has a great influence on the mechanical properties of the membranes. The higher the content of MCC, the better the comprehensive mechanical properties of the membranes. When the MCC content is 9%, the tensile strength is 8.38 MPa and the elongation at break is 26.72%. Finally, the separation properties of membrane studed by separation bovine serum albumin (BSA) from water. The results showed that the rejection rate and water flux changed positively and negatively with the change of MCC content. When the content was 5%, MCC membrane showed the best comprehensive performance, its rejection of BSA was 37.23 g/(m2·h), and the corresponding rejection rate and water flux were 88.87% and 41.89 L/(m2·h) respectively.