Study On Preparation For Macrocrystalline Cellulose Of Reed Pulp

The main raw material to product microcrystalline cellulose (MCC) is often the naturalfiber, such as the wood and the cotton linter, however, forest resources and cotton fields arelimited in the country, it will be facing more and more difficulties to prepare MCC. Reed isabundant renewable biomass resources, it is widen distributed and high yield in our countryand it also contains a lot of cellulose. Reed as a new raw material to product MCC hasimportant practical significance.It prepared MCC by two different methods in this paper, inorganic acid hydrolysis andionic liquid ([BMIM] Cl) method. Both the optimal process conditions and results were asfollows:(1) Acid hydrolysis: HCl concentration8%,90min,80℃, liquid ratio1:15. The largerimpact of hydrolysis was temperature. Degree of polymerization (DP) was256.88L· g-1,crystallinity79.04%, yield90.23%, ash0.089%.(2)Ionic liquid method:75℃,3h, cellulose concentration2.5wt%. DP328.28L· g-1,crystallinity77.97%, yield84.80%, the dissolution rate0.38%, ash0.05%.Currently, the main method of preparing MCC is acid hydrolysis, it is with low cost andit is easier to achieve large-scale production. However, acid hydrolysis has a fatal weakness:large amount of acid and wash water consumption, it is also difficult to solve the effluent andcorrosive on equipment, those were the pollution problem. Ionic liquids are a new type ofsolvent, they are friendly on environment and they can be recycled. This paper also exploresthe application of ionic liquids after dissolving pulp:Two recovery rates of ionic liquids were all above95%, by comparing the infraredbetween recall and standard ILs, it can be proved that the recall ILs reused again. DP379.56L· g-1, crystallinity67.87%, yield88.51%, dissolution rate0.29%,0.06%ash of thefirst recovery. For the second recovery: DP381.61L· g-1, crystallinity60.59%, yield88.63%,dissolution rate0.28%, ash0.06%. The sugar content was0.8258%after the first recall ionicliquid. Thus, to compared with the conventional inorganic acid or an organic solvent, ionicliquid can be referred to as "green" solvents, it has a promising development, but its price washigher. To explore the feasibility of mass production, further research is needed.