Preparation method of sodium taurate
By optimizing the ammonolysis reaction conditions in a microchannel reactor, the problems of high ammonia excess rate and low conversion rate in traditional sodium taurine production were solved, achieving a highly efficient ammonolysis reaction and a simplified post-processing, thereby improving production efficiency and energy utilization.
Patent Information
- Application Number
- CN202511475434.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-15
- Publication Date
- 2026-01-09
AI Technical Summary
Traditional sodium taurine production suffers from problems such as high ammonia excess rate, low conversion rate, numerous byproducts, and high energy consumption in post-processing, resulting in an inefficient and complex production process.
A microchannel reactor was used for ammonolysis, and the ratio of sodium hydroxyethyl sulfonate to ammonia was controlled at 1:(1.5~10). The reaction conditions, including pressure, temperature and residence time, were optimized by circulating heat transfer oil to improve the conversion rate and reduce the excess ammonia rate.
It significantly improved the conversion rate of ammonolysis, reduced the excess ammonia rate, simplified the post-processing, saved energy, and improved production efficiency.
Abstract
Description
Technical Field
[0001] This invention relates to the field of sodium taurine preparation technology, and more particularly to a method for preparing sodium taurine. Background Technology
[0002] Ammonolysis of hydroxyethyl sulfonates (mainly sodium hydroxyethyl sulfonate or potassium hydroxyethyl sulfonate) is a key reaction process in the production of sodium taurate. In traditional production processes, excess ammonia (typically 13-16 times the molar excess of hydroxyethyl sulfonate) is used in the ammonolysis process under high temperature and pressure in a reaction tower or reactor. This ammonolysis process suffers from drawbacks such as a high ammonia excess coefficient, high reaction temperature and pressure (245-270℃, 20-26MPa), and low conversion rate (only 70-75% conversion rate in a single pass). Furthermore, a significant amount of sodium ditaurate is generated as a byproduct. These problems, especially the excess ammonia and insufficient ammonolysis conversion rate, significantly reduce the efficiency of the entire production process, resulting in high energy consumption and complex post-processing. Therefore, developing a reaction method that can effectively reduce the ammonia excess rate and improve the conversion rate of the ammonolysis reaction is of significant practical importance. Summary of the Invention
[0003] In view of this, the purpose of the present invention is to provide a method for preparing sodium taurine, which can effectively reduce the excess rate of ammonia and improve the conversion rate of ammonia and sodium hydroxyethyl sulfonate.
[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for preparing sodium taurine, comprising the following steps: An aqueous solution containing sodium hydroxyethyl sulfonate and an ammonia-containing liquid are pumped into a microchannel reactor to carry out an ammonolysis reaction to obtain the sodium taurine. The molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid is 1:(1.5~10).
[0005] Preferably, the molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid is 1:(1.5~8).
[0006] Preferably, the molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid is 1:(1.5~6).
[0007] Preferably, the mass concentration of the aqueous solution containing sodium hydroxyethyl sulfonate is 18% to 35%. The ammonia-containing liquid includes liquid ammonia or ammonia water, wherein the mass concentration of the ammonia water is 25% to 28%.
[0008] Preferably, the pumping rate of the aqueous solution containing sodium hydroxyethyl sulfonate is 15~25 mL / min.
[0009] Preferably, the pumping rate of the ammonia-containing liquid is 5~10 mL / min.
[0010] Preferably, the ammonolysis reaction is carried out under heating conditions, and the heating method is heat transfer oil circulation heating; The heat transfer oil used in the circulating heating process has an inlet temperature of 150~245℃ and an outlet temperature of ≤255℃.
[0011] Preferably, the residence time of the aqueous solution containing sodium hydroxyethyl sulfonate and the ammonia-containing liquid in the microchannel reactor is 2 to 12 minutes.
[0012] Preferably, the pressure of the ammonolysis reaction is ≥120 bar.
[0013] Preferably, after the ammonolysis reaction, the reaction system is recovered to obtain recovered ammonia, wherein the recovered ammonia includes recovered ammonia gas and / or recovered ammonia water; When the recovered ammonia is reused, the recovered ammonia is directly mixed with sodium hydroxyethyl sulfonate solution to obtain a sodium hydroxyethyl sulfonate-ammonia mixture. After the molar ratio of sodium hydroxyethyl sulfonate to ammonia reaches the required level, the sodium hydroxyethyl sulfonate-ammonia mixture is pumped into the microchannel reactor for reaction. When reusing the recovered ammonia water, the recovered ammonia water is mixed with sodium hydroxyethyl sulfonate, and then the resulting sodium hydroxyethyl sulfonate-ammonia mixture and liquid ammonia are simultaneously pumped into a microchannel reactor in proportion using micro-flow pumps to carry out the reaction.
[0014] This invention provides a method for preparing sodium taurine, comprising the following steps: pumping an aqueous solution containing sodium hydroxyethyl sulfonate and an ammonia-containing liquid into a microchannel reactor to carry out an ammonolysis reaction to obtain the sodium taurine; the molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid is 1:(1.5~10). The preparation method of this invention significantly reduces the excess ammonia rate during the ammonolysis reaction, improves the reaction conversion rate, effectively utilizes the heat of solution during the dissolution of high-concentration ammonia water, and saves the refrigerant consumed in traditional methods to maintain a relatively constant system temperature when high-concentration ammonia water is introduced into the sodium hydroxyethyl sulfonate solution. Detailed Implementation
[0015] This invention provides a method for preparing sodium taurine, comprising the following steps: An aqueous solution containing sodium hydroxyethyl sulfonate and an ammonia-containing liquid are pumped into a microchannel reactor to carry out an ammonolysis reaction to obtain the sodium taurine. The molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid is 1:(1.5~10).
[0016] In this invention, unless otherwise specified, all raw materials used in the preparation are commercially available products well known to those skilled in the art.
[0017] In this invention, the mass concentration of sodium hydroxyethyl sulfonate in the aqueous solution is preferably 18-35%, more preferably 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, or 35%. In embodiments of this invention, the mass concentration of sodium hydroxyethyl sulfonate in the aqueous solution is 20%, 25%, or 30%.
[0018] In this invention, the aqueous solution containing sodium hydroxyethyl sulfonate is preferably an aqueous solution of sodium hydroxyethyl sulfonate or a mixture of sodium hydroxyethyl sulfonate and ammonia obtained by mixing with recycled ammonia.
[0019] In this invention, the pump used to pump in the aqueous solution containing sodium hydroxyethyl sulfonate and ammonia is preferably a micro-flow pump.
[0020] In this invention, the molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid is 1:(1.5~10). In embodiments of this invention, the molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid can be 1:10, 1:6, 1:8, or 1:1.5.
[0021] In this invention, the ammonia-containing liquid preferably includes liquid ammonia or ammonia water, and the mass concentration of the ammonia water is preferably 25% to 28%, more preferably 25%, 26%, 27% or 28%; the purity of the liquid ammonia is preferably 99.8%.
[0022] In this invention, the aqueous solution containing sodium hydroxyethyl sulfonate and ammonia are reacted in a microchannel reactor to ensure good mass transfer between the aqueous solution containing sodium hydroxyethyl sulfonate and ammonia, thereby achieving thorough mixing of ammonia and sodium hydroxyethyl sulfonate.
[0023] In this invention, the pumping rate of the aqueous solution containing sodium hydroxyethyl sulfonate is preferably 15-25 mL / min. In embodiments of this invention, the pumping rate of the aqueous solution containing sodium hydroxyethyl sulfonate can be 22 mL / min, 18 mL / min, 23 mL / min, or 21 mL / min.
[0024] In this invention, the pumping rate of the ammonia-containing liquid is preferably 5-10 mL / min. In embodiments of this invention, the pumping rate of the ammonia-containing liquid can be 9.1 mL / min, 5.3 mL / min, 7 mL / min, or 5 mL / min.
[0025] In this invention, the ammonolysis reaction is preferably carried out under heating conditions, and the heating method is preferably heat transfer oil circulation heating. The inlet temperature of the heat transfer oil used for heat transfer oil circulation heating is preferably 150~245℃, more preferably 150℃, 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 230℃, 240℃ or 245℃; the outlet temperature is preferably ≤255℃. In this invention, the inlet temperature of the heat transfer oil is adaptively adjusted according to the ammonia water flow rate, with the outlet temperature of the microchannel reactor not exceeding 255℃ as a standard.
[0026] In this invention, the residence time of the aqueous solution containing sodium hydroxyethyl sulfonate and the ammonia-containing liquid in the microchannel reactor is preferably 2 to 12 minutes. In embodiments of this invention, the residence time can be 3.2 minutes, 4.3 minutes, 3.3 minutes, or 3.6 minutes.
[0027] In this invention, when the aqueous solution containing sodium hydroxyethyl sulfonate is pumped in, the temperature of the sodium hydroxyethyl sulfonate is preferably ≤40°C; when the ammonia water is pumped in, the temperature of the ammonia water is preferably ≤30°C.
[0028] In this invention, the density of the reaction system obtained by mixing the aqueous solution containing sodium hydroxyethyl sulfonate and ammonia in a microchannel reactor is preferably 0.9~1.05 g / cm³. 3 .
[0029] In this invention, the pressure of the ammonolysis reaction is preferably ≥120 bar, more preferably 120~200 bar. In embodiments of this invention, the pressure of the ammonolysis reaction can be 120 bar or 200 bar.
[0030] In this invention, the reaction system is recovered after the ammonolysis reaction to obtain recovered ammonia, wherein the recovered ammonia preferably includes recovered ammonia gas and / or recovered ammonia water; When the recovered ammonia is reused, the recovered ammonia is directly mixed with sodium hydroxyethyl sulfonate solution to obtain a sodium hydroxyethyl sulfonate-ammonia mixture. After the molar ratio of sodium hydroxyethyl sulfonate to ammonia reaches the required level, the sodium hydroxyethyl sulfonate-ammonia mixture is pumped into the microchannel reactor for reaction. When reusing the recovered ammonia water, the recovered ammonia water is mixed with sodium hydroxyethyl sulfonate, and then the resulting sodium hydroxyethyl sulfonate-ammonia mixture and liquid ammonia are simultaneously pumped into a microchannel reactor in proportion using micro-flow pumps to carry out the reaction.
[0031] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.
[0032] Example 1 A 20% sodium hydroxyethyl sulfonate aqueous solution at room temperature was pumped into a 95 mL microchannel reactor at a pumping rate of 22 mL / min using a micro-flow pump. Liquid ammonia at room temperature and 99.8% purity (molar ratio of ammonia to sodium hydroxyethyl sulfonate molecules was 10:1) was also pumped into the same 95 mL microchannel reactor at a pumping rate of 9.1 mL / min. The inlet temperature of the circulating heat transfer oil was maintained at 240 ± 1 °C (ensuring the outlet temperature of the microchannel reactor did not exceed 255 °C). The residence time of the sodium hydroxyethyl sulfonate aqueous solution and liquid ammonia was 3.2 min, and the pressure was 200 bar, yielding sodium taurine (conversion rate of 85.7%).
[0033] Example 2 A 25% sodium hydroxyethyl sulfonate aqueous solution at room temperature was pumped into a 95 mL microchannel reactor at a pumping rate of 18 mL / min using a micro-flow pump. Liquid ammonia at room temperature and 99.8% purity (molar ratio of ammonia to sodium hydroxyethyl sulfonate molecules was 6:1) was also pumped into the same 95 mL microchannel reactor at a pumping rate of 5.3 mL / min. The inlet temperature of the circulating heat transfer oil was maintained at 240 ± 1 °C (ensuring the outlet temperature of the microchannel reactor did not exceed 255 °C). The residence time of the sodium hydroxyethyl sulfonate aqueous solution and ammonia was 4.3 min, and the pressure was 200 bar, yielding sodium taurine (conversion rate of 85.3%).
[0034] Example 3 A 20% sodium hydroxyethyl sulfonate aqueous solution at room temperature was pumped into a 95 mL microchannel reactor at a pumping rate of 23 mL / min using a micro-flow pump. Liquid ammonia at room temperature and 99.8% purity was also pumped into the 95 mL microchannel reactor at a pumping rate of 7 mL / min (the molar ratio of ammonia molecules to sodium hydroxyethyl sulfonate molecules was 8:1). The inlet temperature of the circulating heat transfer oil was maintained at 240 ± 1 °C (ensuring the outlet temperature of the microchannel reactor did not exceed 255 °C). The residence time of the sodium hydroxyethyl sulfonate aqueous solution and the ammonia solution was 3.3 min, and the pressure was 120 bar, yielding sodium taurine (conversion rate 83.7%).
[0035] Example 4 A 30% sodium hydroxyethyl sulfonate aqueous solution at room temperature was pumped into a 95 mL microchannel reactor at a pumping rate of 21 mL / min using a micro-flow pump. A 25% ammonia solution at room temperature was also pumped into the 95 mL microchannel reactor at a pumping rate of 5 mL / min (the molar ratio of ammonia molecules to sodium hydroxyethyl sulfonate molecules in the ammonia solution was 1.5:1). The inlet temperature of the circulating heat transfer oil was maintained at 240 ± 1 °C (ensuring the outlet temperature of the microchannel reactor did not exceed 255 °C). The residence time of the sodium hydroxyethyl sulfonate aqueous solution and the ammonia solution was 3.6 min, and the pressure was 200 bar, yielding sodium taurine (conversion rate 84.3%).
[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing sodium taurine, characterized in that, Includes the following steps: An aqueous solution containing sodium hydroxyethyl sulfonate and an ammonia-containing liquid are pumped into a microchannel reactor to carry out an ammonolysis reaction to obtain the sodium taurine. The molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid is 1:(1.5~10).
2. The preparation method according to claim 1, characterized in that, The molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid is 1:(1.5~8).
3. The preparation method according to claim 2, characterized in that, The molar ratio of sodium hydroxyethyl sulfonate in the aqueous solution to ammonia in the ammonia-containing liquid is 1:(1.5~6).
4. The preparation method according to claim 1, characterized in that, The mass concentration of the aqueous solution containing sodium hydroxyethyl sulfonate is 18%~35%; The ammonia-containing liquid includes liquid ammonia or ammonia water, wherein the mass concentration of the ammonia water is 25% to 28%.
5. The preparation method according to claim 1, characterized in that, The pumping rate of the aqueous solution containing sodium hydroxyethyl sulfonate is 15~25 mL / min.
6. The preparation method according to claim 1, characterized in that, The pumping rate of the ammonia-containing liquid is 5~10 mL / min.
7. The preparation method according to claim 1, characterized in that, The ammonolysis reaction is carried out under heating conditions, and the heating method is heat transfer oil circulation heating; The heat transfer oil used in the circulating heating process has an inlet temperature of 150~245℃ and an outlet temperature of ≤255℃.
8. The preparation method according to claim 1 or 7, characterized in that, The residence time of the aqueous solution containing sodium hydroxyethyl sulfonate and the ammonia-containing liquid in the microchannel reactor is 2-12 min.
9. The preparation method according to claim 8, characterized in that, The pressure of the ammonolysis reaction is ≥120 bar.
10. The preparation method according to claim 1, characterized in that, The reaction system is recovered after the ammonolysis reaction to obtain recovered ammonia; the recovered ammonia includes recovered ammonia gas and / or recovered ammonia water; When the recovered ammonia is reused, the recovered ammonia is directly mixed with sodium hydroxyethyl sulfonate solution to obtain a sodium hydroxyethyl sulfonate-ammonia mixture. After the molar ratio of sodium hydroxyethyl sulfonate to ammonia reaches the required level, the sodium hydroxyethyl sulfonate-ammonia mixture is pumped into the microchannel reactor for reaction. When reusing the recovered ammonia water, the recovered ammonia water is mixed with sodium hydroxyethyl sulfonate, and then the resulting sodium hydroxyethyl sulfonate-ammonia mixture and liquid ammonia are simultaneously pumped into a microchannel reactor in proportion using micro-flow pumps to carry out the reaction.