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With the improvement of people 's quality of life , D-xylose is gradually replaced by sucrose and become the main sweetener xylose preparation process is constantly improved and perfected . However, in the process of the preparation of industrial application of the xylose , a lower yield of xylose and xylose after crystallization of the mother liquor having a higher content of sugar and other defects has not yet been fundamentally improved , how to improve the yield of xylose in the wood the mother liquor after the sugar crystals become effectively extract sugar xylose promotion applications . Secondly , with the development of industrial crystallization , in order to consider the convenience of transportation and storage , the market is also on the particle size and crystalline form of xylose product put forward higher requirements , for the extraction of raw materials for more than two major problems , the paper cotton seed hulls the entire process of the crystals of D-xylose as the research object , with a focus on xylose crystallization yield and product particle size distribution control two aspects of the investigation and study . Firstly, the experiment to get through the entire process of the preparation of D-xylose crystals from cottonseed hulls , discusses the hydrolysis of cotton hulls , neutralization, bleaching , and concentrated , and ion exchange purification many details of the processing , and using a relatively - prepared Solventing white D-xylose new crystallization method . In Secondly, ethanol Solventing the yield influencing factors the crystallization method xylose crystal meticulous research , focusing on the effects of temperature, initial concentration of xylose mother liquor , the amount of ethanol was added , the amount of seed , stirring rate , crystallization time crystallization yield , and to make a variety of factors with yield changes in the quantitative curve Finally , based on uniform design method U intended to level 1 < / sub > 8 ( 18 , < / sup>) crystallization yield optimization, in the xylose mother liquor initial concentration of 72.22% added ethanol concentration was 75.95% , when the seed crystals were added to 0.6g, and the conditions of reaction for 4 hours at 17 ℃ , you can get the optimal xylose yield of 79.85% , far greater than the factory 50 % yield . Finally, the experimental study of the xylose Solventing process granularity control , the effects of temperature , whether to join the seed , stirring rate , xylose mother liquor , the initial concentration of the particle size distribution of the products of the xylose finalized the particle size distribution and the quantitative relationship of these factors , for guiding production practices to provide a reference .
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