Foaming agent as well as preparation method and application thereof

Abstract

The invention provides a foaming agent as well as a preparation method and application thereof, and belongs to the field of foaming agents. The structural formula of the foaming agent is as shown in a formula 1: # imgabs0 #, in the formula 1, n is 1.2-2, and R is an alkyl chain. The foaming agent belongs to alkyl glycoside dimethyl betaine substances, through innovative molecular design, zwitterionic groups of a betaine structure are ingeniously introduced into the molecular structure of alkyl glycoside, the performance of a surfactant is remarkably improved, and the foaming agent has a good foaming effect while the original advantages of alkyl glycoside are reserved. The surfactant has the advantages of good dissolvability and good foam stability of a zwitterionic surfactant. Therefore, the water solubility and the foam performance of the alkyl glycoside foaming agent are improved at the same time.

Description

Technical Field

[0001] The present application relates to the technical field of foaming agents, and in particular to a foaming agent and a preparation method and application thereof. Background Art

[0002] With the rapid development of the aluminum industry, domestic high-grade bauxite is becoming increasingly scarce, and low-grade bauxite has entered the market in large quantities. Among them, high-sulfur bauxite is difficult to be economically processed by the traditional Bayer process because of its high sulfur content, which is harmful to production. The development and utilization of complex and difficult-to-process high-sulfur bauxite resources in China for the alumina industry can extend the service life of my country's bauxite and play a positive role in alleviating the pressure on my country's bauxite resources. Flotation desulfurization is a relatively economical method for blocking the source of high-sulfur bauxite and improving its quality. In flotation operations, flotation agents are usually used to increase or decrease the hydrophobicity of the mineral surface and control the flotation behavior of the mineral to obtain better flotation indicators. The frother not only affects the number and quality of bubbles in mineral flotation, but also affects the contact between mineral particles. In addition, it can promote the separation of hydrophobic mineral particles and hydrophilic mineral particles adhering to the bubbles in the foam layer. Therefore, the quality of the frother will directly affect the flotation index.

[0003] At present, the frother used in bauxite flotation is mainly pine oil, but the active ingredient of pine oil is terpene alcohol with a ring structure, which is difficult to biodegrade, and the foam produced is brittle and easy to break. Alkyl polyglycoside is a kind of non-ionic surfactant with excellent performance. It also has many advantages of anionic surfactants, such as high surface activity, fine and stable foam, excellent compatibility, good biodegradability, etc. Therefore, it is widely used in many fields. However, in practical applications, as the length of the alkyl chain increases, the water solubility of alkyl polyglycoside becomes worse, and the foam performance decreases significantly with the increase of water hardness. Summary of the invention

[0004] The present application provides a foaming agent and a preparation method and application thereof to solve the following technical problem: how to simultaneously improve the water solubility and foaming performance of an alkyl glycoside foaming agent.

[0005] In a first aspect, the present application provides a foaming agent, the structural formula of the foaming agent is shown in Formula 1:

[0006]

[0007] In Formula 1, n is 1.2 to 2, and R is an alkyl chain.

[0008] Optionally, in the structural formula, n is 1.2 to 1.8.

[0009] Optionally, the alkyl chain has 8 to 18 carbon atoms.

[0010] In a second aspect, the present application provides a method for preparing a foaming agent according to any one embodiment of the first aspect, the method comprising:

[0011] Mixing long-chain alkyl polyglycoside, sulfonyl chloride and dimethylamine to carry out a substitution reaction to obtain an alkyl polyglycoside tertiary amine intermediate solution;

[0012] adding sodium chloroacetate to the alkyl polyglucoside tertiary amine intermediate solution to carry out a quaternization reaction to obtain an alkyl polyglucoside dimethyl betaine aqueous solution;

[0013] The alkyl glycoside dimethyl betaine aqueous solution is purified to obtain a foaming agent.

[0014] Optionally, the amount n1 of the long-chain alkyl polyglycoside, the amount n2 of the sulfonyl chloride and the amount n3 of the dimethylamine satisfy the following relationship: n1:n2:n3=1:(1.2~2):(1.2~2).

[0015] Optionally, the temperature of the substitution reaction is 40°C to 100°C, and the time of the substitution reaction is 3h to 8h.

[0016] Optionally, the amount n1 of the long-chain alkyl glycoside and the amount n4 of the sodium chloroacetate satisfy the following relationship: n1:n4=1:(1-2).

[0017] Optionally, the temperature of the quaternization reaction is 50° C. to 100° C., and the time of the quaternization reaction is 3 h to 6 h.

[0018] Optionally, the purification treatment of the alkyl glycoside dimethyl betaine aqueous solution comprises:

[0019] The alkyl glycoside dimethyl betaine aqueous solution is subjected to reduced pressure distillation and desalination treatment in sequence to purify the alkyl glycoside dimethyl betaine aqueous solution; wherein the pressure of the reduced pressure distillation is 3kPa to 10kPa, and the desalting agent of the desalination treatment is ethanol.

[0020] In a third aspect, the present application provides an application of the frother described in any one of the embodiments in the first aspect, wherein the frother is used for flotation desulfurization of high-sulfur bauxite.

[0021] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0022] The present application provides a foaming agent, which belongs to the class of alkyl polyglycoside dimethyl betaine substances. Through innovative molecular design, the zwitterionic group of the betaine structure is cleverly introduced into the molecular structure of the alkyl polyglycoside, achieving a significant improvement in the performance of the surfactant. On the one hand, the introduction of the betaine structure into the alkyl polyglycoside can make the newly formed surfactant molecules achieve a better balance between hydrophilicity and lipophilicity, thereby improving their solubility in water; at the same time, the introduction of betaine will reduce the critical micelle concentration of the alkyl polyglycoside, so that a stable micelle structure can be formed at a lower concentration, thereby helping the surfactant molecules to be better dispersed and dissolved in water, further improving their water solubility. On the other hand, the positive and negative charges in the betaine structure can form a double electric layer structure at the gas-liquid interface, enhancing the mechanical strength and stability of the interfacial film; the charge effect also helps to reduce the charge repulsion on the interface, so that more surfactant molecules can be adsorbed on the interface to form a more compact and stable foam layer; at the same time, the alkyl polyglycoside and the betaine structure have a synergistic effect in foam generation. Therefore, the alkyl glucoside betaine surfactant retains the original advantages of alkyl glucoside while having the advantages of good solubility and foam stability of zwitterionic surfactants, thereby improving the water solubility and foam performance of alkyl glucoside foaming agents. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0025] Figure 1 A schematic flow chart of a method for preparing a foaming agent provided in an embodiment of the present application;

[0026] Figure 2 A process flow chart of flotation desulfurization of high-sulfur bauxite provided in the embodiment of the present application;

[0027] Figure 3 A graph showing the relationship between the surface tension and concentration of the foaming agent provided in Example 4 of the present application;

[0028] Figure 4 This is a foam optical image of the high-sulfur bauxite flotation desulfurization process provided in Example 4 of the present application. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0030] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0031] In addition, in the description of the specification of the present application, the terms "including", "comprising", etc. mean "including but not limited to". In this article, relational terms such as "first" and "second", etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A and B can be singular or plural. In this article, "at least one" means one or more, and "plurality" means two or more. "At least one", "the following at least one item (items)" or similar expressions refer to any combination of these items, including any combination of single items (items) or plural items (items). For example, "at least one of a, b, or c", or "at least one of a, b and c", can both mean: a, b, c, ab (i.e. a and b), ac, bc or abc, where a, b, c can be single or plural, respectively.

[0032] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0033] The present application provides a foaming agent, the structural formula of the foaming agent is shown in Formula 1:

[0034]

[0035] In Formula 1, n is 1.2 to 2, and R is an alkyl chain.

[0036] As shown in Formula 1, the foaming agent belongs to a polymer molecule, and n represents the average degree of polymerization of the polymer molecule. The average degree of polymerization means that each polymer is composed of homologous polymer molecules with different degrees of polymerization, and its degree of polymerization has a statistical average meaning. n represents the average value of the number of repeating units contained in the polymer macromolecular chain based on the number of repeating units.

[0037] Alkyl polyglycosides are a class of nonionic surfactants with excellent performance. They also have many advantages of anionic surfactants, such as high surface activity, fine and stable foam, excellent compatibility, and good biodegradability. Therefore, they are widely used in many fields. However, in practical applications, the water solubility of alkyl polyglycosides deteriorates with the increase of alkyl chain length, and the foam performance decreases significantly with the increase of water hardness. In order to utilize the excellent properties of alkyl polyglycosides and improve their shortcomings, the polyhydroxy groups in the molecular structure of alkyl polyglycosides can be used to modify alkyl polyglycosides, introduce functional groups on the hydroxyl groups, and obtain alkyl polyglycoside derivatives with unique performance, which is a new research direction in the field of alkyl polyglycoside surfactants. Betaines are a type of zwitterionic surfactants with both cationic and anionic groups. They can remain stable in a wide pH range and show excellent solubility and compatibility. At the same time, betaines can produce rich and stable foams, which are suitable for application scenarios that require good foam properties.

[0038] The alkyl polyglycoside dimethyl betaine foaming agent shown in Formula 1 cleverly introduces the zwitterionic group of the betaine structure into the molecular structure of the alkyl polyglycoside through innovative molecular design, thus significantly improving the performance of the surfactant. The details are as follows:

[0039] 1. The alkyl glycoside dimethyl betaine foaming agent has excellent solubility:

[0040] On the one hand, after the introduction of the betaine structure, the newly synthesized alkyl glycoside betaine surfactant reached a better balance between hydrophilicity and lipophilicity, and this balance significantly improved the solubility of the surfactant in water. On the other hand, the introduction of betaine effectively reduced the critical micelle concentration of alkyl glycoside, which means that a stable micelle structure can be formed at a lower concentration, which not only improves the utilization rate of the surfactant, but also promotes its more uniform dispersion and dissolution in water, further enhancing its water solubility.

[0041] 2. The alkyl glycoside dimethyl betaine foaming agent has excellent foaming performance:

[0042] On the one hand, the double-layer structure formed by the positive and negative charges in the betaine structure at the gas-liquid interface significantly enhances the mechanical strength and stability of the interfacial film. This stability helps the foam layer not to break easily when subjected to external forces, thereby extending the durability of the foam. On the other hand, the existence of the charge effect reduces the charge repulsion between molecules on the interface, allowing more surfactant molecules to be tightly adsorbed on the interface to form a tighter and more stable foam layer, which not only improves the quality of the foam, but also enhances the efficiency of foam generation. Alkyl polyglycosides and betaine structures show significant synergistic effects in foam generation. The two work together to improve the foam performance of the foaming agent, giving it a wider application prospect in occasions where efficient foam generation is required (such as washing, cleaning, foam fire extinguishing, etc.).

[0043] While introducing the betaine structure, the foaming agent still retains many of the original advantages of alkyl glycosides, such as good biodegradability, low toxicity, mildness to the skin, etc. This makes the foaming agent have extremely high application value in the fields of environmental protection and personal care.

[0044] With its excellent solubility and foaming properties, the alkyl glycoside dimethyl betaine foaming agent can be widely used in detergents, cosmetics, oil field exploitation, foam fire extinguishing agents and other fields to meet the needs of different industries for high-efficiency foaming agents.

[0045] The reaction equation for introducing the zwitterionic group of betaine structure on the basis of the original molecular structure of alkyl glycoside is as follows:

[0046]

[0047] In some embodiments, in the structural formula, n is 1.2 to 1.8.

[0048] In some embodiments, the alkyl chain has 8 to 18 carbon atoms.

[0049] The average degree of polymerization n of the foaming agent is limited to 1.2 to 1.8, and the intermolecular force is relatively weak, which is conducive to the water solubility and diffusivity of the molecule, and is also conducive to the generation and stability of the foam. The number of carbon atoms in the alkyl chain is limited to 8 to 18, and the alkyl glycoside with an alkyl chain length greater than 8 carbons can form an effective adsorption layer on the water-air interface, thereby reducing the surface tension. As the alkyl chain grows, this adsorption capacity will increase, resulting in a further reduction in surface tension, so that the alkyl glycoside has better decontamination and wetting properties. However, when the number of carbon atoms in the alkyl chain is greater than 18, the solubility of the alkyl glycoside in water will decrease. Exemplary, the average degree of polymerization n can be 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, etc., and the number of carbon atoms in the alkyl chain can be 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, etc.

[0050] Figure 1 A schematic flow chart of a method for preparing a foaming agent provided in an embodiment of the present application.

[0051] See also Figure 1 The present application provides a method for preparing a foaming agent as described in any one of the above embodiments, the method comprising:

[0052] S1, mixing a long-chain alkyl polyglycoside, sulfonyl chloride and dimethylamine to carry out a substitution reaction to obtain an alkyl polyglycoside tertiary amine intermediate solution;

[0053] The hydroxyl part of long-chain alkyl polyglycoside (APG) is substituted by sulfonyl chloride and dimethylamine through a substitution reaction to form an intermediate containing a tertiary amine group.

[0054] In some embodiments, the reactant long-chain alkyl polyglycoside is a 50% solution purchased directly.

[0055] In some embodiments, the amount n1 of the long-chain alkyl polyglycoside, the amount n2 of the sulfonyl chloride, and the amount n3 of the dimethylamine satisfy the following relationship: n1:n2:n3=1:(1.2~2):(1.2~2).

[0056] Sulfonyl chloride and dimethylamine are in excess relative to the long-chain alkyl polyglycoside to promote the complete reaction of the long-chain alkyl polyglycoside. Exemplarily, the amount n1 of the long-chain alkyl polyglycoside, the amount n2 of the sulfonyl chloride and the amount n3 of the dimethylamine satisfy the following relationship: n1:n2:n3=1:1.2:1.2, 1:1.3:1.3, 1:1.4:1.4, 1:1.5:1.5, 1:1.6:1.6, 1:1.7:1.7, 1:1.8:1.8, 1:1.9:1.9 or 1:2:2, etc.

[0057] In some embodiments, the temperature of the substitution reaction is 40° C. to 100° C., and the time of the substitution reaction is 3 h to 8 h.

[0058] The temperature of the substitution reaction is limited to 40°C to 100°C, and the time of the substitution reaction is 3h to 8h. The activity of the reactants is guaranteed, which helps to fully carry out the substitution reaction, and at the same time ensures that the reactants have enough time to contact and react, thereby improving the reaction efficiency. And avoid the occurrence of unnecessary side reactions. Exemplarily, the temperature of the substitution reaction can be 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, etc., and the time of the substitution reaction can be 3h, 4h, 5h, 6h, 7h, 8h, etc.

[0059] S2, adding sodium chloroacetate to the alkyl polyglucoside tertiary amine intermediate solution to carry out a quaternization reaction to obtain an alkyl polyglucoside dimethyl betaine aqueous solution;

[0060] The alkyl glycoside tertiary amine intermediate obtained in step S1 is subjected to a quaternization reaction with sodium chloroacetate to generate alkyl glycoside dimethyl betaine having zwitterionic properties.

[0061] In some embodiments, the amount n1 of the long-chain alkyl glycoside and the amount n4 of the sodium chloroacetate satisfy the following relationship: n1:n4=1:(1-2).

[0062] Sodium chloroacetate is in excess relative to the long-chain alkyl polyglycoside to promote the complete reaction of the long-chain alkyl polyglycoside. Exemplarily, the amount n1 of the long-chain alkyl glycoside and the amount n4 of the sodium chloroacetate satisfy the following relationship: n1:n4=1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, etc.

[0063] In some embodiments, the temperature of the quaternization reaction is 50° C. to 100° C., and the time of the quaternization reaction is 3 h to 6 h.

[0064] The temperature of the quaternization reaction is limited to 50°C to 100°C, and the time of the quaternization reaction is 3h to 6h. The activity of the reactants is guaranteed, which helps to fully carry out the substitution reaction, and at the same time ensures that there is enough time for the reactants to contact and react, thereby improving the reaction efficiency. And avoid the occurrence of unnecessary side reactions. Exemplarily, the temperature of the substitution reaction can be 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, etc., and the time of the substitution reaction can be 3h, 3.5h, 4h, 5h, 5.5h, 6h, etc.

[0065] S3, purifying the alkyl glycoside dimethyl betaine aqueous solution to obtain a foaming agent.

[0066] Impurities in the reaction product are removed through purification treatment to improve the purity and performance of the foaming agent.

[0067] In some embodiments, the purification of the alkyl glycoside dimethyl betaine aqueous solution comprises:

[0068] The alkyl glycoside dimethyl betaine aqueous solution is subjected to reduced pressure distillation and desalination treatment in sequence to purify the alkyl glycoside dimethyl betaine aqueous solution; wherein the pressure of the reduced pressure distillation is 3kPa to 10kPa, and the desalting agent of the desalting treatment is ethanol.

[0069] Vacuum distillation is a distillation method carried out at a pressure lower than normal pressure to remove water from the aqueous solution of alkyl glycoside dimethyl betaine, and the desalination treatment is to remove inorganic salts and other soluble ionic impurities in alkyl glycoside dimethyl betaine. The pressure of vacuum distillation is limited to 3kPa to 10kPa, which can reduce the distillation temperature and thus reduce the risk of thermal decomposition of the product. Exemplarily, the pressure of vacuum distillation can be 3kPa, 4kPa, 5kPa, 6kPa, 7kPa, 8kPa, 9kPa, 10kPa, etc.

[0070] The product prepared by the method for preparing the foaming agent is the foaming agent mentioned above. The structure of the foaming agent prepared by the method for preparing the foaming agent can refer to the above embodiment. Since the method for preparing the foaming agent adopts part or all of the technical solutions of the foaming agent embodiment, it at least has all the beneficial effects brought by the technical solutions of the foaming agent embodiment, which will not be described one by one here.

[0071] Based on a general inventive concept, the present application provides an application of a frother as described in any one of the above embodiments, wherein the frother is used for flotation desulfurization of high-sulfur bauxite.

[0072] Figure 2 This is a process flow chart for flotation desulfurization of high-sulfur bauxite provided in an embodiment of the present application.

[0073] See also Figure 2 In the embodiment of the present invention, a frother is used for flotation desulfurization of high-sulfur bauxite. The flotation desulfurization experiment process is as follows: weigh the high-sulfur bauxite, grind it to a certain fineness, put it into the flotation tank of the flotation machine for slurry adjustment, adjust the pH value, add an activator, a collector, and a frother in sequence, and then scrape the bubbles to conduct a flotation desulfurization experiment. The flotation desulfurization of high-sulfur bauxite includes 1 roughing, 2 fine selections, and 3 scavenging (one roughing, two fine selections, and three scavenging). The sulfur content of the aluminum concentrate product obtained by the flotation desulfurization process of high-sulfur bauxite is ≤0.4%, which meets the requirements of the Bayer process for producing alumina.

[0074] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following examples are usually measured according to industry standards. If there is no corresponding industry standard, then the conditions recommended by the manufacturer are followed.

[0075] Example 1

[0076] In a 250ml three-necked flask with a condenser, add 0.020mol long-chain alkyl polyglycoside APG0810 and 0.024mol sulfonyl chloride in sequence, heat to 60°C, add 0.024mol dimethylamine while stirring, and react for 4h to obtain APG0810 tertiary amine intermediate; then take 0.020mol sodium chloroacetate solid particles and add them directly to the APG0810 tertiary amine intermediate solution, heat to 80°C for quaternization reaction, react for 4h, and remove water from the obtained aqueous solution under reduced pressure distillation at 5kPa pressure, and desalt with ethanol to obtain APG0810 dimethyl betaine foaming agent. The frother is used for flotation desulfurization of high-sulfur bauxite, with a grinding fineness of 75-85%, a "one roughing, two refining, and three scavenging" flotation process, a pH value of 4.5, a collector dosage of 250g / t (roughing) + 100g / t (refining one) + 50g / t (refining two) + 0g / t (scavenging), a frother dosage of 100g / t (roughing) + 40g / t (refining one) + 20g / t (refining two) + 0g / t (scavenging), and an aluminum concentrate with a sulfur content of 0.32% and a yield of 73.39% and a sulfur concentrate with a sulfur content of 31.89% and a yield of 26.61% are obtained.

[0077] Example 2

[0078] In a 250ml three-necked flask with a condenser, add 0.020mol long-chain alkyl polyglycoside APG0814 and 0.024mol sulfonyl chloride in sequence, heat to 60°C, add 0.024mol dimethylamine while stirring, and react for 4h to obtain APG0814 tertiary amine intermediate; then take 0.020mol sodium chloroacetate solid particles and add them directly to the APG0810 tertiary amine intermediate solution, heat to 80°C for quaternization reaction, react for 4h, and remove water from the obtained aqueous solution under reduced pressure distillation at 5kPa pressure, and desalt with ethanol to obtain APG0814 dimethyl betaine foaming agent. The frother is used for flotation desulfurization of high-sulfur bauxite, with a grinding fineness of 75-85%, a "one roughing, two refining, and three scavenging" flotation process, a pH value of 4.5, a collector dosage of 250g / t (roughing) + 100g / t (refining one) + 50g / t (refining two) + 0g / t (scavenging), a frother dosage of 100g / t (roughing) + 40g / t (refining one) + 20g / t (refining two) + 0g / t (scavenging), and an aluminum concentrate with a sulfur content of 0.34% and a yield of 76.68% and a sulfur concentrate with a sulfur content of 36.27% and a yield of 23.32% are obtained.

[0079] Example 3

[0080] In a 250ml three-necked flask with a condenser, add 0.020mol long-chain alkyl polyglycoside APG0816 and 0.024mol sulfonyl chloride in sequence, heat to 60°C, add 0.024mol dimethylamine while stirring, and react for 4h to obtain APG0816 tertiary amine intermediate; then take 0.020mol sodium chloroacetate solid particles and add them directly to the APG0810 tertiary amine intermediate solution, heat to 80°C for quaternization reaction, react for 4h, and remove water from the obtained aqueous solution under reduced pressure distillation at 5kPa pressure, and desalt with ethanol to obtain APG0816 dimethyl betaine foaming agent. The frother is used for flotation desulfurization of high-sulfur bauxite, with a grinding fineness of 75-85%, a "one roughing, two refining, and three scavenging" flotation process, a pH value of 4.5, a collector dosage of 250g / t (roughing) + 100g / t (refining one) + 50g / t (refining two) + 0g / t (scavenging), a frother dosage of 100g / t (roughing) + 40g / t (refining one) + 20g / t (refining two) + 0g / t (scavenging), and an aluminum concentrate with a sulfur content of 0.36% and a yield of 71.87% and a sulfur concentrate with a sulfur content of 30.08% and a yield of 28.13% are obtained.

[0081] Example 4

[0082] In a 250ml three-necked flask with a condenser, add 0.020mol long-chain alkyl polyglycoside APG1214 and 0.024mol sulfonyl chloride in sequence, heat to 60°C, add 0.024mol dimethylamine while stirring, and react for 4h to obtain APG1214 tertiary amine intermediate; then take 0.020mol sodium chloroacetate solid particles and add them directly to the APG0810 tertiary amine intermediate solution, heat to 80°C for quaternization reaction, react for 4h, and remove water from the obtained aqueous solution under reduced pressure distillation at 5kPa pressure, and desalt with ethanol to obtain APG1214 dimethyl betaine foaming agent. The frother is used for flotation desulfurization of high-sulfur bauxite, with a grinding fineness of 75-85%, a "one roughing, two fines, three scavenging" flotation process, a pH value of 4.5, a collector dosage of 250g / t (roughing) + 100g / t (fine one) + 50g / t (fine two) + 0g / t (scavenging), a frother dosage of 100g / t (roughing) + 40g / t (fine one) + 20g / t (fine two) + 0g / t (scavenging), and an aluminum concentrate with a sulfur content of 0.27% and a yield of 77.75% and a sulfur concentrate with a sulfur content of 38.25% and a yield of 22.25% are obtained.

[0083] Example 5

[0084] In a 250ml three-necked flask with a condenser, add 0.020mol long-chain alkyl polyglycoside APG1216 and 0.024mol sulfonyl chloride in sequence, heat to 60°C, add 0.024mol dimethylamine while stirring, and react for 4h to obtain APG1216 tertiary amine intermediate; then take 0.020mol sodium chloroacetate solid particles and add them directly to the APG0810 tertiary amine intermediate solution, heat to 80°C for quaternization reaction, react for 4h, and remove water from the obtained aqueous solution under reduced pressure distillation at 5kPa pressure, and desalt with ethanol to obtain APG1216 dimethyl betaine foaming agent. The frother is used for flotation desulfurization of high-sulfur bauxite, with a grinding fineness of 75-85%, a "one roughing, two refining, and three scavenging" flotation process, a pH value of 4.5, a collector dosage of 250g / t (roughing) + 100g / t (refining one) + 50g / t (refining two) + 0g / t (scavenging), a frother dosage of 100g / t (roughing) + 40g / t (refining one) + 20g / t (refining two) + 0g / t (scavenging), and an aluminum concentrate with a sulfur content of 0.39% and a yield of 72.18% and a sulfur concentrate with a sulfur content of 30.33% and a yield of 27.82% are obtained.

[0085] Comparative Example 1

[0086] A flotation desulfurization experiment was carried out using APG0810 alkyl glycoside as a flotation desulfurization frother for high-sulfur bauxite. The grinding fineness was 75-85%, and the flotation process of "one roughing, two refining, and three scavenging" was adopted. The pH value was 4.5, the amount of collector was 250g / t (roughing) + 100g / t (refining one) + 50g / t (refining two) + 0g / t (scavenging), and the amount of frother was 100g / t (roughing) + 40g / t (refining one) + 20g / t (refining two) + 0g / t (scavenging). An aluminum concentrate with a sulfur content of 1.29% and a yield of 73.18% and a sulfur concentrate with a sulfur content of 28.99% and a yield of 26.82% were obtained.

[0087] Comparative Example 2

[0088] A flotation desulfurization experiment was carried out using APG1214 alkyl glycoside as a flotation desulfurization frother for high-sulfur bauxite. The grinding fineness was 75-85%, and the flotation process of "one roughing, two refining, and three scavenging" was adopted. The pH value was 4.5, the amount of collector was 250g / t (roughing) + 100g / t (refining one) + 50g / t (refining two) + 0g / t (scavenging), and the amount of frother was 100g / t (roughing) + 40g / t (refining one) + 20g / t (refining two) + 0g / t (scavenging). An aluminum concentrate with a sulfur content of 0.87% and a yield of 75.25% and a sulfur concentrate with a sulfur content of 32.59% and a yield of 24.75% were obtained.

[0089] Comparative Example 3

[0090] The flotation desulfurization experiment was carried out using pine oil as a flotation desulfurization frother for high-sulfur bauxite. The grinding fineness was 75-85%, and the flotation process of "one roughing, two refining, and three scavenging" was adopted. The pH value was 4.5, the amount of collector was 250g / t (roughing) + 100g / t (refining one) + 50g / t (refining two) + 0g / t (scavenging), and the amount of frother was 100g / t (roughing) + 40g / t (refining one) + 20g / t (refining two) + 0g / t (scavenging). An aluminum concentrate with a sulfur content of 0.25% and a yield of 77.82% and a sulfur concentrate with a sulfur content of 38.44% and a yield of 22.18% were obtained.

[0091] The flotation results of Examples 1 to 5 and Comparative Examples 1 to 3 are shown in Table 1:

[0092] Table 1 Flotation results of Examples 1 to 5 and Comparative Examples 1 to 3

[0093]

[0094]

[0095] As can be seen from Table 1, under the same high-sulfur bauxite sample and the same flotation process conditions, the flotation concentrates obtained by using alkyl polyglucoside dimethyl betaine as flotation desulfurization frothers can basically meet the requirements of Bayer process for producing alumina. Among them, the aluminum concentrate obtained by APG1214 dimethyl betaine has the lowest sulfur content, and the corresponding alkyl polyglucoside frother has the best flotation desulfurization effect. In addition, the flotation desulfurization frother can effectively reduce the surface tension of the solution, and the foam produced is uniform and stable, with good flotation desulfurization foaming ability.

[0096] Figure 3 The surface tension and concentration relationship diagram of the foaming agent provided in Example 4 of the present application. Figure 3 It can be seen that as the concentration of the foaming agent increases, the surface tension gradually decreases.

[0097] Figure 4 This is an optical image of the foam during the flotation desulfurization process of high-sulfur bauxite provided in Example 4 of the present application. Figure 4 It can be seen that the bubbles generated by alkyl glycoside dimethyl betaine as flotation desulfurization foaming agent are uniform and stable, which can effectively drive the flotation of sulfur-containing minerals, thereby realizing the desulfurization of bauxite.

[0098] In addition, one or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0099] In the embodiments of the present invention, the prepared foaming agent can effectively reduce the surface tension of the solution, and the generated foam is uniform and stable, which is suitable for the separation of high-sulfur bauxite, is beneficial to improving the bauxite beneficiation indicators, and improves the comprehensive utilization rate of resources.

[0100] In the embodiment of the present invention, pine oil frother is commonly used in bauxite flotation, and its effective component is terpene alcohol with a ring structure. The present invention adopts alkyl glycoside dimethyl betaine as flotation desulfurization frother, which solves the problem that terpene alcohol is difficult to biodegrade and the foam is brittle and easy to break.

[0101] In the embodiment of the present invention, the prepared foaming agent has the characteristics of strong foaming ability, high temperature resistance, high mineralization resistance, and good compatibility with formation water.

[0102] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A foaming agent, characterized in that The structural formula of the foaming agent is shown in Formula 1: In Formula 1, n is 1.2 to 2, and R is an alkyl chain.

2. The foaming agent according to claim 1, characterized in that In the structural formula, n is 1.2 to 1.

8.

3. The foaming agent according to claim 1, characterized in that The alkyl chain has 8 to 18 carbon atoms.

4. A method for preparing a foaming agent according to any one of claims 1 to 3, characterized in that: The method comprises: Mixing long-chain alkyl polyglycoside, sulfonyl chloride and dimethylamine to carry out a substitution reaction to obtain an alkyl polyglycoside tertiary amine intermediate solution; adding sodium chloroacetate to the alkyl polyglucoside tertiary amine intermediate solution to carry out a quaternization reaction to obtain an alkyl polyglucoside dimethyl betaine aqueous solution; The alkyl glycoside dimethyl betaine aqueous solution is purified to obtain a foaming agent.

5. The method according to claim 4, characterized in that The amount n1 of the long-chain alkyl polyglycoside, the amount n2 of the sulfonyl chloride and the amount n3 of the dimethylamine satisfy the following relationship: n1:n2:n3=1:(1.2~2):(1.2~2).

6. The method according to claim 4, characterized in that The temperature of the substitution reaction is 40° C. to 100° C., and the time of the substitution reaction is 3 h to 8 h.

7. The method according to claim 4, characterized in that The amount n1 of the long-chain alkyl glycoside and the amount n4 of the sodium chloroacetate satisfy the following relationship: n1:n4=1:(1-2).

8. The method according to claim 4, characterized in that The temperature of the quaternization reaction is 50° C. to 100° C., and the time of the quaternization reaction is 3 h to 6 h.

9. The method according to claim 4, characterized in that The purification treatment of the alkyl glycoside dimethyl betaine aqueous solution comprises: The alkyl glycoside dimethyl betaine aqueous solution is subjected to reduced pressure distillation and desalination treatment in sequence to purify the alkyl glycoside dimethyl betaine aqueous solution; wherein the pressure of the reduced pressure distillation is 3kPa to 10kPa, and the desalting agent of the desalination treatment is ethanol.

10. Use of the foaming agent according to any one of claims 1 to 3, characterized in that: The frother is used for flotation desulfurization of high-sulfur bauxite.

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