Phosphite antioxidants have important application value in the field of raw materials for chemical production, and their main function is to inhibit oxidation reaction and prolong the service life of products. This article will introduce the manufacturing method of phosphite antioxidants in detail, including raw material preparation, reaction process, post-treatment and product quality control.
I. Raw material preparation
1. Phosphite: Phosphite is the main raw material for the preparation of phosphite antioxidants, and food-grade phosphite is generally used to ensure its high purity, which is conducive to the subsequent reaction.
2. Alcohols: Alcohols are another important raw material in phosphite antioxidants, and common alcohols include ethanol, propanol, butanol and so on. Alcohols with higher purity should be selected to ensure product quality.
3. Catalyst: The catalyst has an important influence on the synthesis reaction of phosphite antioxidants, and the common catalysts include sulfuric acid, hydrochloric acid and other acid catalysts.
2. Reaction process
1. Pre-treatment: Add the raw material of alcohol into the reactor, turn on the stirring, and heat it to the predetermined temperature.
2. Dropwise addition of phosphite: under the condition of stirring and heating, slowly dropwise addition of phosphite, and control the dropwise acceleration to make the reaction proceed smoothly.
3. Reaction control: During the titration process, pay close attention to the changes of the reaction temperature, pressure and other parameters, and make timely adjustments as needed to ensure that the reaction proceeds smoothly.
4. Post-treatment: After the reaction is completed, carry out cooling, filtration, washing and other operations to get the crude product.
3. Post-treatment and product quality control
1. Purification of crude product: carry out vacuum distillation, crystallization and other purification operations on the crude product to obtain antioxidants with high purity of phosphite ester.
2. Product quality testing: Through gas chromatography, mass spectrometry and other analytical means, test the purity, acidity, chromaticity and other key indexes of the product to ensure that the product quality meets the relevant standards.
4. Precautions
1. In the production process, the proportion of each raw material should be strictly controlled to ensure that the reaction generates the required phosphite antioxidant.
2. The selection of catalyst and the amount of catalyst used have important influence on the reaction speed and product quality, and should be adjusted according to the actual situation.
3. In the process of dropping phosphite, the reaction temperature should be kept stable to avoid local overheating to trigger side reactions.
4. In the post-treatment process, attention should be paid to the purification and quality control of the product to ensure the stability and application performance of the product.
In conclusion, the manufacturing method of phosphite antioxidants involves several links and considerations, and requires strict control of each parameter and operation step in the actual production process to ensure the quality and yield of the products. At the same time, for different alcohols and phosphite antioxidant products, the specific manufacturing method may vary, so in the actual operation process should be adjusted and optimized according to the specific product requirements and raw material characteristics.
