Scale inhibitor for sodium carbonate mother liquor and preparation method thereof

Abstract

The invention relates to the technical field of scale inhibition, and provides a scale inhibitor for sodium carbonate mother liquor and a preparation method of the scale inhibitor. The invention discloses a scale inhibitor for sodium carbonate mother liquor. The scale inhibitor comprises the following raw material components in parts by weight: 50-75 parts of polyacrylic acid, 30-50 parts of polyepoxysuccinic acid, 5-12 parts of a surfactant, 2-16 parts of sodium gallate, 1-10 parts of sodium lactate, 1-7 parts of a stabilizer, 0.5-4.5 parts of a dispersing agent and 30-50 parts of water. According to the technical scheme, the problem of low scale inhibition rate of the scale inhibitor for the sodium carbonate mother liquor in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of scale inhibition, and in particular to a scale inhibitor for soda ash mother liquor and a preparation method thereof. Background Art

[0002] Soda ash, as an important basic chemical raw material, is widely used in many fields such as glass, chemical industry, metallurgy, etc. Its production process involves complex process links. In the soda ash production process, soda ash mother liquor plays a key role. However, the mother liquor system is prone to scaling problems, which brings many troubles to soda ash production and also gives rise to the research and development and application of scale inhibitors for soda ash mother liquor.

[0003] From the perspective of soda ash production process, the ammonia-soda method or the combined soda method is mostly used. Taking the ammonia-soda method as an example, limestone is calcined to produce quicklime and carbon dioxide, and quicklime is digested to obtain slaked lime, which then reacts with the mother liquor containing ammonium chloride to produce calcium hydroxide and ammonium chloride. In the subsequent steps, carbon dioxide reacts with ammonia salt water to produce sodium bicarbonate, which is calcined to obtain soda ash. In this series of conversion processes, the mother liquor is continuously recycled, which is rich in a large amount of calcium, magnesium ions, and anions such as carbonate and sulfate. With the circulation of the mother liquor, the concentration of these ions gradually accumulates. When a certain saturation is reached, they will combine to form insoluble precipitates such as calcium carbonate, magnesium carbonate, and calcium sulfate, which adhere to the inner wall of the equipment pipeline to form a scale layer.

[0004] Scaling has serious consequences for soda ash production. On the one hand, the thickening of the scale layer will greatly reduce the heat transfer efficiency of the equipment, making it impossible to transfer the heat required for the reaction in time, resulting in a slower reaction rate, longer production cycle, and lower production efficiency. On the other hand, the scale layer will increase the fluid resistance of the pipeline, reduce the flow cross-sectional area of ​​the fluid, make it difficult to transport the mother liquor, increase the energy consumption of the pump, and may even cause pipeline blockage, resulting in production interruption and high maintenance costs.

[0005] Traditional descaling methods such as mechanical cleaning and chemical cleaning have obvious limitations. Mechanical cleaning is time-consuming and labor-intensive, and requires production suspension, during which the company will face huge economic losses. Although chemical cleaning does not require production suspension, the chemical cleaning agents used are often corrosive and can easily cause secondary damage to the equipment. In addition, the treatment of waste liquid after cleaning is also a major problem, which can cause environmental pollution if not handled with care. Faced with these difficulties, the development of efficient scale inhibitors for soda ash mother liquor has become a top priority.

[0006] The scale inhibition rate of existing soda ash mother liquor antiscalants is still relatively low. Therefore, it is very important to develop a soda ash mother liquor antiscalant with a high scale inhibition rate. Summary of the invention

[0007] The invention provides a scale inhibitor for soda ash mother liquor and a preparation method thereof, which solves the problem of low scale inhibition rate of the scale inhibitor for soda ash mother liquor in the related art.

[0008] The invention provides a scale inhibitor for soda ash mother liquor. The raw materials include the following components by weight: 50-75 parts of polyacrylic acid, 30-50 parts of polyepoxysuccinic acid, 5-12 parts of surfactant, 2-16 parts of sodium gallate, 1-10 parts of sodium lactate, 1-7 parts of stabilizer, 0.5-4.5 parts of dispersant and 30-50 parts of water.

[0009] As a further technical solution, the mass ratio of sodium gallate to sodium lactate is 2-4:1.

[0010] As a further technical solution, the mass ratio of sodium gallate to sodium lactate is 3:1.

[0011] As a further technical solution, the surfactant includes one or more of dodecyl dimethyl betaine, sodium dodecyl sulfonate, and sodium lauroyl amphoacetate; the stabilizer includes sodium alginate; and the dispersant includes isopropanolamine.

[0012] As a further technical solution, the polyepoxysuccinic acid is a modified polyepoxysuccinic acid, and the raw materials of the modified polyepoxysuccinic acid include polyepoxysuccinic acid and pent-4-en-1-amine.

[0013] The present invention uses pent-4-ene-1-amine modified polyepoxysuccinic acid to further improve the scale inhibition rate of the scale inhibitor for soda ash mother liquor.

[0014] As a further technical solution, the preparation process of the modified polyepoxysuccinic acid comprises the following steps: adding the polyepoxysuccinic acid to water, adding an initiator in an inert gas atmosphere, mixing, adding pent-4-en-1-amine, reacting, concentrating, and drying to obtain the modified polyepoxysuccinic acid; The mass ratio of the polyepoxysuccinic acid to water is 1:3-5.

[0015] As a further technical solution, the mass ratio of the polyepoxysuccinic acid to the pent-4-en-1-amine is 20:1~3.

[0016] In the present invention, the mass ratio of polyepoxysuccinic acid to pent-4-ene-1-amine is adjusted to 20:1-3, thereby further improving the scale inhibition rate of the scale inhibitor for soda ash mother liquor.

[0017] As a further technical solution, the initiator includes one of sodium persulfate and ammonium persulfate, and the mass ratio of the polyepoxysuccinic acid to the initiator is 30:0.5~1.5.

[0018] As a further technical solution, the reaction temperature is 25-45°C and the reaction time is 2-4h.

[0019] The present invention also provides a method for preparing a scale inhibitor for soda ash mother liquor, comprising the following steps: uniformly mixing various components of the raw materials to obtain the scale inhibitor for the soda ash mother liquor.

[0020] The working principle and beneficial effects of the present invention are: In the present invention, polyepoxysuccinic acid molecules are rich in two characteristic functional groups, carboxyl and ether bonds. When polyepoxysuccinic acid is dissolved in water, it will ionize carboxyl anions, and as the alkalinity of the solution increases, the carboxyl anions will stretch the molecular chain structure from a curved state to a straight chain, exposing more negatively charged groups to the outside. If scale is generated, the straight chain structure will adsorb the microcrystals of the scale and roll them into the chain, so that the micro-chelation of the scale forms a coordination bond and generates a soluble chelate. Therefore, polyepoxysuccinic acid can show excellent scale inhibition effect in a high alkalinity environment, and the scale inhibition rate is better. The unshared electron pairs of the carboxyl, hydroxyl and oxygen atoms in the ether bond of the polyepoxysuccinic acid molecule can form coordination bonds with the empty orbitals of the iron atom, thereby playing a role in corrosion inhibition. Sodium gallate and sodium lactate chelate with metal ions, and the synergistic effect of sodium gallate and sodium lactate improves the scale inhibition rate of the scale inhibitor for soda mother liquor. DETAILED DESCRIPTION

[0021] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In the following examples and comparative examples, the weight average molecular weight of polyacrylic acid is 2000; the model of polyepoxysuccinic acid is PESA-L.

[0023] Example 1 A scale inhibitor for soda ash mother liquor, the raw materials comprising the following components by weight: 75 parts of polyacrylic acid, 50 parts of polyepoxysuccinic acid, 12 parts of sodium lauroylamphoacetate, 16 parts of sodium gallate, 1 part of sodium lactate, 7 parts of sodium alginate, 4.5 parts of isopropanolamine, and 50 parts of water; The preparation method thereof comprises the following steps: The components of the raw materials are mixed evenly to obtain a scale inhibitor for soda ash mother liquor.

[0024] Example 2 A scale inhibitor for soda ash mother liquor, the raw materials comprising the following components by weight: 50 parts of polyacrylic acid, 30 parts of polyepoxysuccinic acid, 5 parts of sodium dodecyl sulfonate, 2 parts of sodium gallate, 10 parts of sodium lactate, 1 part of sodium alginate, 0.5 parts of isopropanolamine, and 30 parts of water; The preparation method thereof comprises the following steps: The components of the raw materials are mixed evenly to obtain a scale inhibitor for soda ash mother liquor.

[0025] Example 3 A scale inhibitor for soda ash mother liquor, the raw materials comprising the following components by weight: 65 parts of polyacrylic acid, 40 parts of polyepoxysuccinic acid, 8 parts of dodecyl dimethyl betaine, 10 parts of sodium gallate, 2 parts of sodium lactate, 5 parts of sodium alginate, 3.5 parts of isopropanolamine, and 40 parts of water; The preparation method thereof comprises the following steps: The components of the raw materials are mixed evenly to obtain a scale inhibitor for soda ash mother liquor.

[0026] Example 4 The only difference between this embodiment and embodiment 3 is that the raw materials of this embodiment include the following components by weight: 65 parts of polyacrylic acid, 40 parts of polyepoxysuccinic acid, 8 parts of dodecyl dimethyl betaine, 3 parts of sodium gallate, 9 parts of sodium lactate, 5 parts of sodium alginate, 3.5 parts of isopropanolamine, and 40 parts of water.

[0027] Example 5 The only difference between this embodiment and embodiment 3 is that the raw materials of this embodiment include the following components by weight: 65 parts of polyacrylic acid, 40 parts of polyepoxysuccinic acid, 8 parts of dodecyl dimethyl betaine, 8 parts of sodium gallate, 4 parts of sodium lactate, 5 parts of sodium alginate, 3.5 parts of isopropanolamine, and 40 parts of water.

[0028] Example 6 The only difference between this embodiment and embodiment 3 is that the raw materials of this embodiment include the following components by weight: 65 parts of polyacrylic acid, 40 parts of polyepoxysuccinic acid, 8 parts of dodecyl dimethyl betaine, 9 parts of sodium gallate, 3 parts of sodium lactate, 5 parts of sodium alginate, 3.5 parts of isopropanolamine, and 40 parts of water.

[0029] Example 7 The only difference between this embodiment and embodiment 3 is that the raw materials of this embodiment include the following components by weight: 65 parts of polyacrylic acid, 40 parts of polyepoxysuccinic acid, 8 parts of dodecyl dimethyl betaine, 9.6 parts of sodium gallate, 2.4 parts of sodium lactate, 5 parts of sodium alginate, 3.5 parts of isopropanolamine, and 40 parts of water.

[0030] Example 8 The difference between this embodiment and embodiment 6 is that the raw materials of this embodiment include the following components by weight: 65 parts of polyacrylic acid, 40 parts of modified polyepoxysuccinic acid, 8 parts of dodecyl dimethyl betaine, 9 parts of sodium gallate, 3 parts of sodium lactate, 5 parts of sodium alginate, 3.5 parts of isopropanolamine, and 40 parts of water; The preparation process of modified polyepoxysuccinic acid comprises the following steps: adding 30 parts of polyepoxysuccinic acid to 120 parts of water, adding 1 part of sodium persulfate in an inert gas atmosphere, mixing, adding pent-4-en-1-amine, reacting at 35° C. for 3 hours, concentrating, and drying to obtain modified polyepoxysuccinic acid; The mass ratio of polyepoxysuccinic acid to pent-4-en-1-amine is 5:1.

[0031] Example 9 The only difference between this embodiment and embodiment 8 is that the mass ratio of polyepoxysuccinic acid to pent-4-en-1-amine in this embodiment is 30:1.

[0032] Example 10 The only difference between this embodiment and embodiment 8 is that the mass ratio of polyepoxysuccinic acid to pent-4-en-1-amine in this embodiment is 20:1.

[0033] Embodiment 11 The only difference between this embodiment and embodiment 8 is that the mass ratio of polyepoxysuccinic acid to pent-4-en-1-amine in this embodiment is 10:1.

[0034] Example 12 The only difference between this embodiment and embodiment 8 is that the mass ratio of polyepoxysuccinic acid to pent-4-en-1-amine in this embodiment is 20:3.

[0035] Comparative Example 1 The only difference between this comparative example and Example 2 is that the raw materials of this comparative example include the following components by weight: 50 parts of polyacrylic acid, 30 parts of polyepoxysuccinic acid, 5 parts of sodium dodecyl sulfate, 12 parts of sodium gallate, 1 part of sodium alginate, 0.5 parts of isopropanolamine, and 30 parts of water.

[0036] Comparative Example 2 The only difference between this comparative example and Example 2 is that the raw materials of this comparative example include the following components by weight: 50 parts of polyacrylic acid, 30 parts of polyepoxysuccinic acid, 5 parts of sodium dodecyl sulfate, 12 parts of sodium lactate, 1 part of sodium alginate, 0.5 parts of isopropanolamine, and 30 parts of water.

[0037] Comparative Example 3 The only difference between this comparative example and Example 2 is that the raw materials of this comparative example include the following components by weight: 50 parts of polyacrylic acid, 30 parts of polyepoxysuccinic acid, 5 parts of sodium dodecyl sulfate, 2 parts of sodium gallate, 10 parts of sodium citrate, 1 part of sodium alginate, 0.5 parts of isopropanolamine, and 30 parts of water.

[0038] Comparative Example 4 The only difference between this comparative example and Example 2 is that the raw materials of this comparative example include the following components by weight: 50 parts of polyacrylic acid, 30 parts of polyepoxysuccinic acid, 5 parts of sodium dodecyl sulfate, 1 part of sodium alginate, 0.5 parts of isopropanolamine, and 30 parts of water.

[0039] Test example The scale inhibitor for soda ash mother solution prepared in Examples 1 to 12 of the present invention and Comparative Examples 1 to 4 was tested according to the following method: GB / T 16632-2019 "Calcium Carbonate Deposition Method for Determination of Scale Inhibition Performance in Water Treatment" is used to prepare a test solution with prepared water containing a certain amount of bicarbonate and calcium ions and a water treatment agent. Under heating conditions, calcium bicarbonate is accelerated to decompose into calcium carbonate. After reaching equilibrium, the calcium ion concentration in the test solution is measured. The scale inhibition performance η of the scale inhibitor is expressed as a percentage and calculated according to the following formula: η=(ρ4-ρ3)×100 / (ρ-ρ3) ρ4 is the calcium ion (Ca 2+ ) is the mass concentration value in milligrams per milliliter (mg / mL); ρ3 is the calcium ion (Ca 2+ ) is the mass concentration value in milligrams per milliliter (mg / mL); ρ is the calcium ion (Ca 2+ ) is the mass concentration value in milligrams per milliliter (mg / mL); Water treatment agent test solution: 1.0 mL contains 0.500 mg of the prepared soda ash mother solution scale inhibitor; the amount of water treatment agent added to each test solution is 12 mL / L.

[0040] Prepare water: Add 250mL of water to a 500mL volumetric flask, and use a burette to add a certain volume of calcium chloride standard solution so that the amount of calcium ions is 120mg. Use a pipette to add the water treatment agent sample solution at 12mL / L and shake well. Then add 20mL of borax buffer solution and shake well. Use a burette to slowly add a certain volume of sodium bicarbonate standard solution (shaking while adding) so that the amount of bicarbonate ions is 366mg. Dilute with water to the scale and shake well.

[0041] The experimental results are shown in Table 1.

[0042]

[0043] Comparing Example 2 with Comparative Examples 1 to 4, it is shown that the sodium gallate and sodium lactate in the present invention produce a synergistic effect, thereby improving the scale inhibition rate of the scale inhibitor for soda ash mother liquor.

[0044] Comparing Examples 5 to 7 with Examples 3 to 4, it is shown that the scale inhibition rate of the scale inhibitor for soda ash mother liquor is improved by adjusting the mass ratio of sodium gallate to sodium lactate to 2 to 4:1 in the present invention; and comparing Example 6 with Examples 5 and 7, it is shown that when the mass ratio of sodium gallate to sodium lactate is adjusted to 3:1, the improvement effect is better. Comparing Examples 8 to 12 with Example 6, it is shown that the use of pent-4-ene-1-amine to modify polyepoxysuccinic acid in the present invention further improves the scale inhibition rate of the scale inhibitor for soda ash mother liquor; comparing Examples 10 to 12 with Examples 8 to 9, it is shown that when the mass ratio of polyepoxysuccinic acid to pent-4-ene-1-amine is adjusted to 20:1 to 3 in the present invention, the scale inhibition rate of the scale inhibitor for soda ash mother liquor is further improved; comparing Example 11 with Examples 10 and 12, it is shown that when the mass ratio of polyepoxysuccinic acid to pent-4-ene-1-amine is 10:1, the scale inhibition effect of improving the scale inhibitor for soda ash mother liquor is best.

[0045] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A scale inhibitor for soda ash mother liquor, characterized in that: The raw materials include the following components by weight: 50-75 parts of polyacrylic acid, 30-50 parts of polyepoxysuccinic acid, 5-12 parts of surfactant, 2-16 parts of sodium gallate, 1-10 parts of sodium lactate, 1-7 parts of stabilizer, 0.5-4.5 parts of dispersant and 30-50 parts of water.

2. A scale inhibitor for soda ash mother liquor according to claim 1, characterized in that: The mass ratio of the sodium gallate to the sodium lactate is 2-4:

1.

3. A scale inhibitor for soda ash mother liquor according to claim 2, characterized in that: The mass ratio of the sodium gallate to the sodium lactate is 3:

1.

4. The scale inhibitor for soda ash mother liquor according to claim 1, characterized in that: The surfactant includes one or more of dodecyl dimethyl betaine, sodium dodecyl sulfonate, and sodium lauroyl amphoacetate; the stabilizer includes sodium alginate; and the dispersant includes isopropanolamine.

5. The scale inhibitor for soda ash mother liquor according to claim 1, characterized in that: The polyepoxysuccinic acid is a modified polyepoxysuccinic acid, and the raw materials of the modified polyepoxysuccinic acid include polyepoxysuccinic acid and pent-4-ene-1-amine.

6. The scale inhibitor for soda ash mother liquor according to claim 5, characterized in that: The preparation process of the modified polyepoxysuccinic acid comprises the following steps: adding the polyepoxysuccinic acid into water, adding an initiator in an inert gas atmosphere, mixing, adding pent-4-en-1-amine, reacting, concentrating, and drying to obtain the modified polyepoxysuccinic acid; The mass ratio of the polyepoxysuccinic acid to water is 1:3-5.

7. The scale inhibitor for soda ash mother liquor according to claim 6, characterized in that: The mass ratio of the polyepoxysuccinic acid to the pent-4-en-1-amine is 20:1-3.

8. The scale inhibitor for soda ash mother liquor according to claim 6, characterized in that: The initiator comprises one of sodium persulfate and ammonium persulfate, and the mass ratio of the polyepoxysuccinic acid to the initiator is 30:0.5-1.

5.

9. The scale inhibitor for soda ash mother liquor according to claim 6, characterized in that: The reaction temperature is 25-45°C and the reaction time is 2-4 hours.

10. The method for preparing a scale inhibitor for soda ash mother solution according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: uniformly mixing various components of the raw materials to obtain the scale inhibitor for the soda ash mother liquor.

Images