Method for preparing large-particle sodium bicarbonate based on additive

Abstract

The invention provides a large-particle sodium bicarbonate crystal product and a preparation method thereof, sodium chloride and ammonium bicarbonate are used as raw materials, a certain amount of additive is added into a NaCl solution to regulate and control the generation of large-particle sodium bicarbonate, and the large-particle sodium bicarbonate product is obtained through the steps of adding ammonium bicarbonate for reaction crystallization, cooling, filtering and drying. The additive is at least one of sodium dodecyl benzene sulfonate, lauryl sodium sulfate and sodium dodecyl sulfate. The large-particle sodium bicarbonate product is simple in preparation process, stable in process, low in energy consumption, high in economical efficiency, high in reproducibility and free of complex equipment. The one-time yield of the product reaches 60% or above, the cycle yield reaches 98% or above, and the purity of the product reaches 99.5% or above. The obtained large-particle sodium bicarbonate is spherical, and the particle size is large (D50gt; 300 [mu] m), the particle size distribution is uniform, the bulk density is high, the fluidity is good, and filtering and drying are easy.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical industry and relates to a method for preparing large-particle sodium bicarbonate, in particular to a method for preparing large-particle sodium bicarbonate by adding a certain amount of additives into brine. Background Art

[0002] Large-particle sodium bicarbonate (NaHCO3) is an important inorganic compound that has attracted much attention due to its wide application in food, medicine, chemical industry and environmental protection. With the acceleration of industrialization and the improvement of environmental protection requirements, the market demand for high-purity, large-particle sodium bicarbonate is also gradually increasing. This demand has prompted various industries to explore more environmentally friendly and sustainable production processes.

[0003] Traditional sodium bicarbonate production methods often rely on high-energy consumption and high-cost chemical reactions, and may bring about three wastes, resulting in waste of resources and environmental burden. The current methods for preparing large-particle sodium bicarbonate mainly include double decomposition method, natural ore method, waste salt solution method, etc. Among them, the double decomposition method prepares sodium bicarbonate by reacting carbonate with acid. Although the process is simple and the resource utilization rate is high, there are problems such as unstable product quality and uneven particle distribution, which affects the market competitiveness of the product. The natural ore method relies on abundant mineral resources, but the mining cost and resource availability have become key factors limiting its expansion. In addition, the feasibility of the waste salt solution method still needs to overcome the influence of existing impurities through technological innovation.

[0004] Therefore, developing a new production process to achieve environmentally friendly production and stably obtain large-particle sodium bicarbonate will help meet the growing market demand and promote the rational use of resources and environmental protection. The realization of this goal is of great significance to promoting the development of related industries and improving product competitiveness.

[0005] Chinese patent CN115650259A introduces a method for preparing large-particle sodium bicarbonate by carbonization of soda ash. The produced sodium bicarbonate particles are spindle-shaped or nearly spherical, have good fluidity, and the particle size range of 180-425μm accounts for more than 80%. The quality meets the standards of the "Chinese Pharmacopoeia" and is suitable for hemodialysis. However, this method requires multiple special equipment and precisely controlled multi-step reactions, and the operation is complicated. In addition, Chinese patent CN104136372B introduces a soda carbonization method using polycarboxylic acid and / or its salt as an additive, but the equipment is complex and the operation is cumbersome, and the product particles are small; the double decomposition rule of Chinese patent CN112919502A only obtains powdered sodium bicarbonate with uneven particle size distribution; Chinese patent CN118026219A prepares spherical large-particle sodium bicarbonate by adding one or more additives of sodium polyacrylate, polyacrylamide, hydroxymethyl cellulose, and sodium tartrate to brine. Although the effect is obvious, the cost of such additives is high, which increases the production cost; Chinese patent CN110282638A discloses that solid ammonium bicarbonate is added to an ammonium bicarbonate dissolver and mixed with brine to complete the double decomposition process. However, increasing the volume of the reaction solution of the unit product (producing an equal amount of sodium bicarbonate) and changing the addition method of the raw material solid ammonium bicarbonate greatly increase the equipment cost, and the particle size of the sodium bicarbonate produced is also relatively small.

[0006] Therefore, it is very necessary to provide a method for preparing large-particle sodium bicarbonate with high efficiency and low cost. Summary of the invention

[0007] The object of the present invention is to provide a large-particle sodium bicarbonate product, which is obtained by a crystallization method of preparing large-particle sodium bicarbonate by first adding a certain amount of additives to a sodium chloride solution and then adding ammonium bicarbonate. The obtained large-particle sodium bicarbonate has a large particle size (D 50 >300μm), the particle size distribution curve is as shown in the attached Figure 1 As shown. The particle size distribution is uniform, easy to filter and dry, good fluidity, easy to store and transport, and the additives used are low-priced, which is conducive to cost saving.

[0008] In order to achieve the above object, the present invention provides a method for preparing a large-particle sodium bicarbonate product, comprising the following steps:

[0009] Step 1: Dissolve sodium chloride NaCl and additives in deionized water;

[0010] Step 2: Add ammonium bicarbonate and allow to react until it no longer dissolves;

[0011] Step 3: Add sodium bicarbonate seeds and continue stirring;

[0012] Step 4: Add ammonium bicarbonate to react fully;

[0013] Step 5: Cool the solution to 0-10°C; preferably 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10°C and ranges therebetween;

[0015] Step 6: Filter and wash the product obtained in step 5;

[0016] Step 7: Dry the product obtained in step 6; after drying, the large-particle sodium bicarbonate product is obtained.

[0017] Preferably, in any of the above items, in step 1, the dissolution temperature is 10 to 50° C. More preferably, it is 10, 20, 30, 40, 50° C. and ranges therebetween.

[0018] In any of the above, the mass ratio of sodium chloride to water is preferably 1.3:10 to 3.5:10, more preferably 1.3:10, 2.0:10, 2.5:10, 3.0:10, 3.5:10.

[0019] Any of the above is preferably that in step 1, the additive is at least one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, and sodium dodecyl sulfonate.

[0020] Preferably, any of the above items has a mass of the additive added of 0.001%-0.3% of the mass of the sodium chloride in step 1. More preferably, it is 0.001%, 0.005%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3% and ranges therebetween.

[0021] In step 2, the mass ratio of the amount of ammonium bicarbonate added to the water in step 1 is 0.3:10 to 1.0:10. More preferably, it is 0.3:10, 0.5:10, 1.0:10 and the range therebetween.

[0022] Any of the above is preferably that in step 3, the sodium bicarbonate seed crystal D 50 >50μm.

[0023] Any of the above is preferably that in step 3, the amount of sodium bicarbonate seed crystals added is 0.05% to 1% of the mass of the sodium chloride added in step 1. More preferably, it is 0.05%, 0.1%, 0.5%, 1% and the range therebetween.

[0024] Preferably, in any of the above items, in steps 2 and 4, the mass ratio of the total mass of ammonium bicarbonate added to the sodium chloride added in step 1 is 0.6:1 to 1.5:1. More preferably, it is 0.6:1, 1.0:1, 1.5:1 and the range therebetween.

[0025] Preferably, in any of the above items, in step 5, the solution heating and cooling rate is 5°C / h to 20°C / h, and more preferably, 5, 10, 15, 20°C / h and the range therebetween.

[0026] Preferably, in any of the above items, in step 6, the washing solution used for washing is one or more of anhydrous ethanol, saturated sodium bicarbonate solution, and 0-5° C. ice water.

[0027] Preferably, in any of the above items, in step 7, the drying temperature is 35-55° C. More preferably, it is 35, 40, 45, 55° C. and the range therebetween.

[0028] Preferably, in any of the above items, in step 7, the drying time is 2 to 6 hours, more preferably 2, 3, 4, 5, 6 hours and the range therebetween.

[0029] The present invention also provides a large-particle sodium bicarbonate, wherein the large-particle sodium bicarbonate is spherical, and the particle size D of the large-particle sodium bicarbonate is 50 The large-particle sodium bicarbonate has a crystal X-ray powder diffraction pattern at diffraction angles 2θ=15.0±0.2, 18.3±0.2, 21.9±0.2, 23.8±0.2, 25.6±0.2, 27.2±0.2, 27.6±0.2, 28.9±0.2, 29.1±0.2, 30.2±0.2, 31.6±0.2, 33.5±0.2, 34.5±0.2, 35.5±0.2, 36.8±0. There are characteristic peaks at 2, 37.3±0.2, 38.0±0.2, 39.0±0.2, 40.8±0.2, 43.5±0.2, 44.4±0.2, 45.7±0.2, 46.1±0.2, 46.9±0.2, 47.5±0.2, 48.6±0.2, 48.6±0.2, 49.7±0.2, 50.0±0.2, 51.2±0.2, 52.6±0.2, 53.2±0.3, and 54.3±0.2 degrees.

[0030] Preferably, the molecular formula of the large-particle sodium bicarbonate product is NaHCO3.

[0031] Any of the above is preferably that the particle size D of the large-particle sodium bicarbonate is 50 Greater than 300 μm, further the particle size D of the large particle sodium bicarbonate 50 The preferred range is 301, 310, 350, 400 μm and ranges therebetween.

[0032] The crystal X-ray powder diffraction pattern of the large-particle sodium bicarbonate product of the present invention is shown in the attached Figure 2 The SEM and polarized light microscope images of the large-particle sodium bicarbonate product are shown in Figure 3, as shown in 4. In step 3, the SEM image of the sodium bicarbonate seed crystal is as shown Figure 5 shown.

[0033] The large-particle sodium bicarbonate is prepared according to any one of the above-mentioned preparation methods.

[0034] In a preferred embodiment of the present invention, the preparation method of the large-particle sodium bicarbonate product is as follows:

[0035] (1) Dissolve a certain amount of sodium chloride (NaCl) in deionized water, add a certain amount of additives, and stir for 30 to 60 minutes to fully dissolve;

[0036] (2) First add a certain amount of ammonium bicarbonate (NH4HCO3) and allow it to react until it no longer dissolves;

[0037] (3) Add a certain amount of seed crystals (NaHCO3) and continue stirring for 15 to 30 minutes;

[0038] (4) Add a certain amount of ammonium bicarbonate and allow to react for 30 to 60 minutes;

[0039] (5) Cooling the solution to 0-10°C;

[0040] (6) filtering the product and washing it with a washing liquid;

[0041] (7) Drying the product in a vacuum drying oven;

[0042] (8) obtaining a large-particle sodium bicarbonate product after drying;

[0043] In step (1) of the method, the reaction temperature is 10-50° C., the mass ratio of sodium chloride to water is (1.3-3.5):10, and the added additive is one or more of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, and sodium dodecyl sulfonate, and the added amount is 0.001-0.3% of the mass of sodium chloride;

[0044] In step (2) of the method, the mass ratio of the amount of ammonium bicarbonate added to water is (0.3-1.0):10;

[0045] In step (3) of the method, sodium bicarbonate D 50 >50μm, the added amount is 0.05% to 1% of the mass of sodium chloride;

[0046] In the method, the mass ratio of the total mass of ammonium bicarbonate added to the mass of sodium chloride in step (4) and step (2) is (0.6-1.5):1;

[0047] In step (5) of the method, the solution temperature rise and fall rate is 5°C / h to 20°C / h;

[0048] In step (6) of the method, the washing liquid is one or more of anhydrous ethanol, saturated sodium bicarbonate solution, and 0-5°C ice water;

[0049] In step (7) of the method, the drying temperature is 35-55° C. and the drying time is 2-6 hours;

[0050] In the method, the crystallization method is reactive crystallization, which is carried out under stirring conditions, and the mother liquor after filtration can be subsequently treated to separate the ammonium chloride and then recycled.

[0051] The large-particle sodium bicarbonate crystal preparation process of the present invention is simple, the process is stable, the economy is high, the reproducibility is high, and no complicated equipment is required. The one-time yield of the crystal product reaches more than 60%, the cycle yield reaches more than 98%, and the product purity reaches more than 99.5%. Compared with the commercially available powdered sodium bicarbonate, the obtained large-particle sodium bicarbonate is spherical, has a uniform particle size distribution, a high bulk density, good fluidity, and is easy to filter and dry. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is the particle size distribution curve of the large-particle sodium bicarbonate product in the preferred embodiment of the present invention.

[0053] Figure 2 It is the X-ray powder diffraction pattern of the large-particle sodium bicarbonate product in the preferred embodiment of the present invention.

[0054] Figure 3 This is a SEM image of large-particle sodium bicarbonate product crystals in a preferred embodiment of the present invention.

[0055] Figure 4 The polarized light microscope image of the large-particle sodium bicarbonate product crystals in the preferred embodiment of the present invention.

[0056] Figure 5 SEM image of commercially available powdered sodium bicarbonate product.

[0057] Figure 6 This is the X-ray powder diffraction pattern of the preferred embodiment 1 of the present invention.

[0058] Figure 7 This is the X-ray powder diffraction pattern of the preferred embodiment 2 of the present invention.

[0059] Figure 8 This is the X-ray powder diffraction pattern of the preferred embodiment 3 of the present invention.

[0060] Fig. 9 This is the X-ray powder diffraction pattern of the preferred embodiment 4 of the present invention.

[0061] Fig.10 This is the X-ray powder diffraction pattern of the preferred embodiment 5 of the present invention. DETAILED DESCRIPTION

[0062] The present invention is further described in detail below through the accompanying drawings and specific embodiments.

[0063] like Figure 1 As shown, it is the particle size distribution curve of the large particle sodium bicarbonate product in the preferred embodiment of the present invention.

[0064] like Figure 2 Shown is an X-ray powder diffraction pattern of a large-particle sodium bicarbonate product in a preferred embodiment of the present invention.

[0065] like Figure 3 Shown is a SEM image of large-particle sodium bicarbonate product crystals in a preferred embodiment of the present invention.

[0066] like Figure 4 Shown is a polarized light microscope image of large-particle sodium bicarbonate product crystals in a preferred embodiment of the present invention.

[0067] like Figure 5 As shown, the SEM image of the commercially available powdered sodium bicarbonate product. The commercially available product was purchased from Tianjin Xiensiopude Technology Co., Ltd., CAS: 144-55-8; purity> 99%.

[0068] Example 1

[0069] (1) Dissolve 30 g of NaCl and 0.015 g of sodium dodecylbenzene sulfonate in 100 ml of deionized water at 20 °C and continue stirring for 1 h to fully dissolve the NaCl solution; (2) Add 5 g of NH4HCO3 and react for 30 min; (3) Add 0.03 g of NaHCO3; (4) Add 30 g of NH4HCO3 and react for 60 min; (5) Cool to 5 °C at a cooling rate of 5 °C / h; (6) Filter the precipitated crystals, wash the filter cake with anhydrous ethanol, and filter with vacuum extraction; (7) After drying, the final product is obtained and tested by PXRD. Figure 6As shown, at 2θ = 15.0 ± 0.2, 18.3 ± 0.2, 21.9 ± 0.2, 23.8 ± 0.2, 25.6 ± 0.2, 27.2 ± 0.2, 27.6 ± 0.2, 28.9 ± 0.2, 29.1 ± 0.2, 30.2 ± 0.2, 31.7 ± 0.2, 33.4 ± 0.2, 34.5 ± 0.2, 35.5 ± 0.2, 36.8 ± 0.2, 37.3 ± 0.2, 38.1 ± 0.2, 39. There are characteristic peaks at 9.0±0.2, 40.8±0.2, 43.5±0.2, 44.5±0.2, 45.6±0.2, 46.1±0.2, 46.9±0.2, 47.5±0.2, 48.6±0.2, 48.6±0.2, 49.7±0.2, 50.0±0.2, 51.3±0.2, 52.6±0.2, 53.2±0.3 and 54.3±0.2 degrees, proving to be sodium bicarbonate crystal product.

[0070] Example 2

[0071] (1) Dissolve 75 g of NaCl and 0.01 g of sodium dodecyl sulfate in 300 ml of deionized water at 50 °C and continue stirring for 1 h to fully dissolve the NaCl solution; (2) Add 15 g of NH4HCO3 and react for 30 min; (3) Add 0.07 g of NaHCO3; (4) Add 60 g of NH4HCO3 and react for 60 min; (5) Cool to 10 °C at a cooling rate of 10 °C / h; (6) Filter the precipitated crystals, wash the filter cake with anhydrous ethanol, and filter with vacuum extraction; (7) After drying, the final product is obtained and tested by PXRD. Figure 7 As shown, at 2θ = 15.0 ± 0.2, 18.3 ± 0.2, 21.9 ± 0.2, 23.8 ± 0.2, 25.6 ± 0.2, 27.2 ± 0.2, 27.6 ± 0.2, 28.9 ± 0.2, 29.1 ± 0.2, 30.1 ± 0.2, 31.6 ± 0.2, 33.5 ± 0.2, 34.5 ± 0.2, 35.5 ± 0.2, 36.8 ± 0.2, 37.3 ± 0.2, 38.0 ± 0.2, 3 There are characteristic peaks at 9.0±0.2, 40.8±0.2, 43.5±0.2, 44.4±0.2, 45.7±0.2, 46.1±0.2, 46.9±0.2, 47.5±0.2, 48.5±0.2, 48.6±0.2, 49.7±0.2, 50.0±0.2, 51.2±0.2, 52.6±0.2, 53.2±0.3 and 54.3±0.2 degrees, proving to be sodium bicarbonate crystal product.

[0072] Example 3

[0073] (1) Dissolve 100 g of NaCl and 0.12 g of sodium dodecyl sulfate in 500 ml of deionized water at 30 °C and stir for 1 h to fully dissolve the NaCl solution; (2) Add 15 g of NH4HCO3 and react for 30 min; (3) Add 0.1 g of NaHCO3; (4) Add 100 g of NH4HCO3 in two portions with an interval of 60 min; (5) Cool to 10 °C at a cooling rate of 5 °C / h; (6) Filter the precipitated crystals, wash the filter cake with saturated sodium bicarbonate solution, and filter with vacuum extraction; (7) Dry to obtain the final product, which is tested by PXRD. Figure 8 As shown, at 2θ = 15.0 ± 0.2, 18.3 ± 0.2, 21.9 ± 0.2, 23.8 ± 0.2, 25.6 ± 0.2, 27.2 ± 0.2, 27.6 ± 0.2, 28.9 ± 0.2, 29.1 ± 0.2, 30.2 ± 0.2, 31.6 ± 0.2, 33.5 ± 0.2, 34.5 ± 0.2, 35.5 ± 0.2, 36.8 ± 0.2, 37.4 ± 0.2, 38.0 ± 0.2, 39. There are characteristic peaks at 9.0±0.2, 40.8±0.2, 43.5±0.2, 44.4±0.2, 45.6±0.2, 46.2±0.2, 46.9±0.2, 47.5±0.2, 48.6±0.2, 48.6±0.2, 49.7±0.2, 50.0±0.2, 51.2±0.2, 52.6±0.2, 53.2±0.3 and 54.2±0.2 degrees, proving to be sodium bicarbonate crystal product.

[0074] Example 4

[0075] (1) Dissolve 30 g of NaCl, 0.05 g of sodium dodecylbenzene sulfonate and 0.05 g of sodium dodecyl sulfonate in 100 ml of deionized water at 40 °C and continue stirring for 1 h to fully dissolve the NaCl solution; (2) Add 5 g of NH4HCO3 and react for 30 min; (3) Add 0.1 g of NaHCO3; (4) Add 25 g of NH4HCO3 and react for 60 min; (5) Cool to 10 °C at a cooling rate of 10 °C / h; (6) Filter the precipitated crystals, wash the filter cake with 5 °C deionized water, and filter with vacuum suction; (7) After drying, the final product is obtained and tested by PXRD. Fig. 9As shown, at 2θ = 15.0 ± 0.2, 18.3 ± 0.2, 21.9 ± 0.2, 23.8 ± 0.2, 25.6 ± 0.2, 27.2 ± 0.2, 27.6 ± 0.2, 28.9 ± 0.2, 29.1 ± 0.2, 30.3 ± 0.2, 31.6 ± 0.2, 33.5 ± 0.2, 34.5 ± 0.2, 35.5 ± 0.2, 36.8 ± 0.2, 37.3 ± 0.2, 38.0 ± 0.2, 39. There are characteristic peaks at 9.0±0.2, 40.8±0.2, 43.5±0.2, 44.4±0.2, 45.7±0.2, 46.1±0.2, 46.9±0.2, 47.4±0.2, 48.6±0.2, 48.6±0.2, 49.7±0.2, 50.0±0.2, 51.2±0.2, 52.6±0.2, 53.2±0.3 and 54.3±0.2 degrees, proving to be sodium bicarbonate crystal product.

[0076] Example 5

[0077] (1) Dissolve 30 g of NaCl, 0.001 g of sodium dodecyl sulfate, 0.002 g of sodium dodecylbenzene sulfonate, and 0.001 g of sodium dodecyl sulfonate in 200 ml of deionized water at 10°C and stir for 1 h to fully dissolve the NaCl solution;

[0078] (2) adding 5 g of NH4HCO3 and reacting for 30 min; (3) adding 0.03 g of NaHCO3; (4) adding 40 g of NH4HCO3 and reacting for 60 min; (5) cooling to 5°C at a cooling rate of 5°C / h; (6) filtering the precipitated crystals, washing the filter cake with anhydrous ethanol, and vacuum filtering; (7) drying to obtain the final product, which was tested by PXRD. Fig.10 As shown, at 2θ = 15.0 ± 0.2, 18.3 ± 0.2, 21.9 ± 0.2, 23.9 ± 0.2, 25.6 ± 0.2, 27.2 ± 0.2, 27.6 ± 0.2, 28.9 ± 0.2, 29.1 ± 0.2, 30.2 ± 0.2, 31.6 ± 0.2, 33.5 ± 0.2, 34.5 ± 0.2, 35.5 ± 0.2, 36.8 ± 0.2, 37.3 ± 0.2, 38.0 ± 0.2, 39. There are characteristic peaks at 9.0±0.2, 40.8±0.2, 43.5±0.2, 44.4±0.2, 45.7±0.2, 46.1±0.2, 46.9±0.2, 47.5±0.2, 48.6±0.2, 48.7±0.2, 49.7±0.2, 50.0±0.2, 51.2±0.2, 52.6±0.2, 53.2±0.3 and 54.3±0.2 degrees, proving to be sodium bicarbonate crystal product.

[0079] The above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A method for preparing a large-particle sodium bicarbonate product, characterized in that: The following steps are involved: Step 1: Dissolve sodium chloride NaCl and additives in deionized water; Step 2: Add ammonium bicarbonate and allow to react until it no longer dissolves; Step 3: Add sodium bicarbonate seeds and continue stirring; Step 4: Add ammonium bicarbonate to react fully; Step 5: Cool the solution to 0-10°C; Step 6: Filter and wash the product obtained in step 5; Step 7: Dry the product obtained in step 6; after drying, the large-particle sodium bicarbonate product is obtained.

2. The preparation method according to claim 1, characterized in that In step 1, the dissolution temperature is 10-50° C.; the mass ratio of sodium chloride to water is 1.3:10-3.5:

10.

3. The preparation method according to claim 1, characterized in that: In step 1, the additive is at least one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, and sodium dodecyl sulfonate; the mass of the additive is 0.001% to 0.3% of the mass of the sodium chloride in step 1.

4. The preparation method according to claim 1, characterized in that: In step 2, the mass ratio of the amount of ammonium bicarbonate added to the water in step 1 is 0.3:10 to 1.0:

10.

5. The preparation method according to claim 1, characterized in that: In step 3, the sodium bicarbonate seed crystal D 50 >50μm, and the amount of the sodium bicarbonate seed crystals added is 0.05% to 1% of the mass of the sodium chloride added in step 1.

6. The preparation method according to claim 1, characterized in that: In steps 2 and 4, the mass ratio of the total mass of ammonium bicarbonate added to the sodium chloride added in step 1 is 0.6:1 to 1.5:

1.

7. The preparation method according to claim 1, characterized in that: In step 5, the solution heating and cooling rate is 5°C / h to 20°C / h.

8. The preparation method according to claim 1, characterized in that: In step 6, the washing solution is one or more of anhydrous ethanol, saturated sodium bicarbonate solution, and 0-5° C. ice water.

9. The preparation method according to claim 1, characterized in that: In step 7, the drying temperature is 35 to 55° C., and the drying time is 2 to 6 hours.

10. The large-particle sodium bicarbonate prepared by the preparation method according to any one of claims 1 to 9, characterized in that: The large-particle sodium bicarbonate is spherical, and the particle size D of the large-particle sodium bicarbonate is 50 The large-particle sodium bicarbonate has a crystal X-ray powder diffraction pattern at diffraction angles 2θ=15.0±0.2, 18.3±0.2, 21.9±0.2, 23.8±0.2, 25.6±0.2, 27.2±0.2, 27.6±0.2, 28.9±0.2, 29.1±0.2, 30.2±0.2, 31.6±0.2, 33.5±0.2, 34.5±0.2, 35.5±0.2, 36.8±0. There are characteristic peaks at 2, 37.3±0.2, 38.0±0.2, 39.0±0.2, 40.8±0.2, 43.5±0.2, 44.4±0.2, 45.7±0.2, 46.1±0.2, 46.9±0.2, 47.5±0.2, 48.6±0.2, 48.6±0.2, 49.7±0.2, 50.0±0.2, 51.2±0.2, 52.6±0.2, 53.2±0.3, and 54.3±0.2 degrees.

Images