Manufacturing method of xylitol
I. INTRODUCTION
Xylitol is an important raw material for the production of chemicals, which is widely used in the fields of food, medicine and cosmetics. Due to its unique sweetness and low-calorie properties, xylitol is widely used as a sweetener in the food industry. In addition, xylitol is also widely used in the field of medicine because of its effectiveness in preventing dental caries and lowering blood sugar. In this paper, we will introduce the manufacturing method of xylitol, including raw material selection, reaction principle, process flow, equipment selection and other aspects.
II. Raw material selection
The raw materials for the manufacture of xylitol are mainly corn cobs, bagasse, cottonseed husk and other agricultural by-products waste, which are rich in xylan components. Among them, corn kernel is the most common raw material, which is widely used in the production of xylitol due to its wide source and low price.
Three, the reaction principle
The manufacture of xylitol is mainly through the acid digestion method or enzyme digestion method to convert the xylan in the raw material into xylose, and then through the hydrogenation reaction to convert xylose into xylitol. The specific reaction principles are as follows:
1. Acid digestion: the xylan in the raw material is hydrolyzed under acidic conditions to produce xylose and other by-products.
2. Enzymatic method: Xylanase is used to hydrolyze the xylan in the raw material to produce xylose.
3. Hydrogenation reaction: Xylose under the action of catalyst and hydrogen undergoes addition reaction to generate xylitol.
4. Process flow
The manufacturing process of xylitol mainly includes raw material treatment, hydrolysis, purification, hydrogenation, crystallization and other steps. The specific process is as follows:
1. Raw material treatment: corn cob and other raw materials are crushed and sieved to get the appropriate particle size.
2. Hydrolysis: Add the treated raw materials into acid or enzyme solution, and carry out the hydrolysis reaction under a certain temperature and time to generate xylose liquid.
3. Purification: The hydrolyzed liquid is neutralized, filtered and decolorized to remove impurities.
4. Hydrogenation: Add the purified xylose liquid into the hydrogenation reactor, and under the action of catalyst, have an addition reaction with hydrogen to produce xylitol liquid.
5. Crystallization: The hydrogenated xylitol liquid is cooled and crystallized to get xylitol crystals.
5. Equipment selection
In the manufacturing process of xylitol, the equipment to be used mainly includes pulverizer, sifter, reactor, filter, decolorization tank, crystallization tank and so on. When selecting the equipment, you need to make comprehensive consideration according to the production scale, product quality, operation and maintenance and other factors, and choose the equipment that suits you.
VI. Precautions
In the manufacturing process of xylitol, the following matters need to be paid attention to:
1. Control the conditions of the hydrolysis and hydrogenation reaction, such as temperature, time, pH, etc., to ensure that the reaction proceeds smoothly.
2. Strengthen the quality testing of raw materials and products to ensure that the product quality meets the requirements.
3. Strengthen the maintenance and upkeep of the equipment to ensure the normal operation and service life of the equipment.
VII.CONCLUSION
Xylitol, as an important raw material for the production of chemicals, has a wide range of application prospects. In the manufacturing process, it is necessary to choose suitable raw materials, control the reaction conditions, strengthen the quality inspection and equipment maintenance to ensure the quality of the product and the smooth production.
