Preparation method of high-quality anhydrous sodium acetate

Abstract

The invention discloses a preparation method of high-quality anhydrous sodium acetate. Comprising the following steps: dropwise adding alkali liquor into acetic acid or an acetic acid solution in a stirring state to obtain a sodium acetate solution, and preparing anhydrous sodium acetate from the sodium acetate solution by using a spray dryer. The sodium acetate solution is directly subjected to spray drying by using the spray dryer, the solution does not need to be concentrated, crystallized and dried, the operation steps are reduced, the process is simple, the yield is high, and the cost is low. The water content of the prepared sodium acetate powder is less than 1.0%, the sodium acetate content is greater than or equal to 99.0%, and the yield is greater than or equal to 98.5%.

Description

Technical Field This invention relates to the field of chemical technology of sodium acetate, and specifically to a method for preparing high-quality anhydrous sodium acetate. Background Technology

[0001] Sodium acetate is used as an esterifying agent in organic synthesis, as well as in photographic chemicals, pharmaceuticals, printing and dyeing mordants, buffers, chemical reagents, meat preservation, pigments, tanning, and many other applications. It can also be used as a pharmaceutical excipient and a carbon source for wastewater treatment.

[0002] Existing methods for preparing anhydrous sodium acetate (CN114539049, CN107417512, etc.) mainly involve first diluting acetic acid with water and then adding it to an alkaline solution, or reacting waste acetic acid with waste alkaline solution. After the reaction is complete, the solution is concentrated and crystallized to obtain sodium acetate trihydrate, which is then dried at high temperature to obtain the finished product. Due to the presence of a large amount of water, the concentration and drying process is time-consuming, energy-intensive, and produces a large amount of mother liquor. Furthermore, the product particle distribution is uneven, affecting its subsequent use. Moreover, the use of waste acid and waste alkaline solution to obtain sodium acetate limits its application in the pharmaceutical and food industries due to safety concerns.

[0003] To address the shortcomings of current methods for preparing anhydrous sodium acetate, this method aims to provide a safe, simple, and convenient production process for anhydrous sodium acetate, yielding high-quality anhydrous sodium acetate. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing anhydrous sodium acetate, which solves the following technical problems: the preparation of anhydrous sodium acetate in the prior art requires concentration, crystallization and drying, which involves many steps and high energy consumption; and the particle size distribution of the prepared anhydrous sodium acetate is uneven.

[0005] The technical method of the present invention is as follows: A method for preparing anhydrous sodium acetate includes the following steps: acetic acid or an aqueous solution of acetic acid is added dropwise with controlled temperature and pH while stirring. After the pH stabilizes, the mixture is stirred for 0.5 hours to obtain an aqueous solution of sodium acetate. The sodium acetate solution is then introduced into a spray dryer, and the inlet and outlet air temperatures are controlled to obtain a white anhydrous sodium acetate product.

[0006] Furthermore, the reaction temperature is controlled at 25~60℃; the reaction pH is controlled at 6.5~7.5.

[0007] Furthermore, the alkaline solution used for adjusting the pH of sodium acetate is one or more aqueous solutions of sodium bicarbonate, sodium carbonate, and sodium hydroxide.

[0008] Furthermore, the feed rate of the spray dryer is 100-200 ml / h, the inlet air temperature is 130-180℃, and the outlet air temperature is 105-125℃.

[0009] The advantages of this invention are: the sodium acetate produced by this invention meets national standards in terms of physicochemical properties, and it appears as a white powder with fine particles and uniform particle size distribution. Compared with the high energy consumption and long time required in traditional concentration and drying processes, this invention reduces post-processing steps, thereby reducing energy consumption and lowering production costs for enterprises.

[0010] Specific Implementation Cases The present invention will be further described in detail below with reference to the embodiments.

[0011] Example 1 Weigh 60g of acetic acid, start stirring, and dilute with 60g of water. Control the temperature at 25℃~30℃, slowly add a 20% NaOH solution dropwise until the pH reaches 6.7. After the pH stabilizes, stir for 0.5h to obtain an aqueous sodium acetate solution. Set the spray dryer to an outlet temperature of 150-160℃, a feed rate of 100ml / h, and an outlet temperature of 120~125℃ to obtain anhydrous sodium acetate white powder.

[0012] Example 2 Weigh 60g of glacial acetic acid and start stirring. Control the temperature at 55℃~60℃ and slowly add saturated sodium bicarbonate solution dropwise until the pH=7.2. After the pH stabilizes, stir for 0.5h to obtain an aqueous sodium acetate solution. Set the spray dryer to an outlet temperature of 130~140℃, a feed rate of 150ml / h, and an outlet temperature of 110~115℃ to obtain anhydrous sodium acetate white powder.

[0013] Example 3 Weigh 60g of glacial acetic acid and dilute it with 60g of water while stirring. Controlling the temperature at 30℃~40℃, slowly add a saturated sodium carbonate solution dropwise until the pH reaches 7.0. After the pH stabilizes, stir for 0.5h to obtain an aqueous sodium acetate solution. Set the spray dryer to an outlet temperature of 140~150℃, a feed rate of 120ml / h, and an outlet temperature of 110~120℃ to obtain anhydrous sodium acetate white powder.

[0014] The results are shown in the table below:

[0015] The sodium acetate produced by this invention meets national standards for physicochemical properties. It is a white powder with fine particles and a uniform particle size distribution. Compared to the high energy consumption and long processing time of traditional concentration and drying processes, this invention reduces post-processing steps, thereby reducing energy consumption and lowering production costs for enterprises.

Claims

1. A method for preparing high-quality anhydrous sodium acetate, characterized in that: An aqueous solution of sodium acetate is obtained by adding alkaline solution dropwise to acetic acid or an aqueous solution of acetic acid; the sodium acetate solution is then spray-dried to obtain a white anhydrous sodium acetate powder.

2. The preparation method according to claim 1, characterized in that: The reaction temperature is controlled at 25~60℃; the reaction pH is controlled at 6.5~7.

5.

3. The preparation method according to claim 1, characterized in that: The alkaline solution is at least one of the aqueous solutions of sodium bicarbonate, sodium carbonate, and sodium hydroxide.

4. The preparation method according to claim 1, characterized in that: The feed rate of the spray dryer is 100-200 ml / h, the inlet air temperature is 130-180℃, and the outlet air temperature is 105-125℃.

Images