A new compound, its preparation method and application

Abstract

The present application relates to a kind of new compounds and its preparation method and application, belong to mineral processing and flotation technology field, solve the problem of existing technology in high alkali, calcium ion-containing environment, easy to lead to target mineral flotation concentrate grade and recovery rate double low, environmental pollution, high cost problem of collector.The compound structure general formula is NaO3S-CH (CH3)- (CH2) n‑2 -O-CO-CH=CH-COONa, wherein, n=8,10~16.The molecular structure of the compound is dumbbell type, sulfonic acid group and carboxylic acid group are located at both ends of carbon chain, can form bidentate chelation with mineral surface together, also can be adsorbed alone, adsorption density is higher, stability is stronger;Two ends of molecule adsorption fixation make alkyl form dense and ordered hydrophobic layer, to improve flotation rate and recovery rate, realize mineral selective flotation.The compound can be used as low-grade tungsten-molybdenum ore flotation collector.

Description

Technical Field

[0001] This invention relates to the field of mineral processing and flotation technology, and in particular to a compound with multiple functional groups, its preparation method and application. Background Technology

[0002] In the field of tungsten and molybdenum mineral processing, the efficient recovery of oxidized tungsten-molybdenum ore is receiving increasing attention due to the depletion of readily available molybdenite and wolframite. Currently, flotation is the core technology for processing these ores, and the performance of the collector is crucial to flotation efficiency. Because oxidized tungsten-molybdenum ore is extremely similar to calcite and other calcium-bearing gangue minerals in crystal structure, surface charge, and solubility, their interfacial behavior during flotation tends to be similar, resulting in poor selectivity of traditional collectors and a long-standing core technical challenge of low separation efficiency and low recovery rate.

[0003] Currently used fatty acid collectors suffer from simple molecular structures and poor mineral surface recognition capabilities. They are prone to non-selective adsorption or deactivation in highly alkaline or calcium-ion-containing environments, resulting in low concentrate grade and recovery rates. To improve separation efficiency, the process relies heavily on modifiers, which not only increases costs and environmental pressures but also easily leads to excessive inhibition of target minerals. Existing hydroxyxamic acid collectors are expensive, hindering their industrial application. Existing phosphorus-containing collectors have limited application due to their significant environmental impact.

[0004] Therefore, in view of the shortcomings of existing collectors in practical applications, there is an urgent need for a new type of high-efficiency collector that is low-cost, environmentally friendly, resistant to hard water and adaptable to high-alkaline media, so as to achieve selective separation of scheelite, calcium molybdate and calcium gangue. Summary of the Invention

[0005] In view of the above analysis, the embodiments of the present invention aim to provide a new compound, its preparation method and application, to solve at least one of the problems in the prior art where collectors in high-alkali, calcium-ion-containing environments easily lead to low flotation concentrate grade and recovery rate of target minerals, environmental pollution and high cost.

[0006] In a first aspect, embodiments of the present invention provide a novel compound, the chemical name of which is sodium (Z)-4-oxo-4-[(9-sulfonyldecyl)oxy]-2-butenoate, and the general structural formula is NaO3S-CH(CH3)-(CH2). n-2 -O-CO-CH=CH-COONa, where n=8,10~16.

[0007] Furthermore, the characteristic is that n is 10~12.

[0008] Furthermore, the compound is sodium (Z)-4-oxo-4-[(9-sulfonyldecyl)oxy]-2-butenoate, with the structural formula as follows: .

[0009] Secondly, embodiments of the present invention provide a method for preparing compounds having multiple functional groups, the method comprising the following steps: S1: React unsaturated fatty alcohols and maleic anhydride to obtain maleic acid monoalkenyl ester; S2: The maleic acid monoalkenyl ester is subjected to a sulfonation reaction with a reagent.

[0010] Furthermore, in step S1, the unsaturated fatty alcohol is specifically at least one of 7-octen-1-ol, 9-decaeno-1-ol, 10-undecen-1-ol, 11-dodecen-1-ol, 12-tridecenol, 13-tetradecenol, 14-pentadecenol, and 15-hexadecenol.

[0011] Furthermore, in step S1, the molar ratio of the unsaturated fatty alcohol to maleic anhydride is 1:(1.0~1.1).

[0012] Furthermore, the reaction temperature is 70~80℃.

[0013] Furthermore, in step S2, the reagent is at least one of sodium sulfite, sodium bisulfite, potassium sulfite, sodium metabisulfite, and potassium metabisulfite.

[0014] Furthermore, in step S2, the molar ratio of the maleic acid monoalkenyl ester to the reagent is 1:(1.0~1.1).

[0015] Furthermore, the sulfonation reaction is carried out at a temperature of 70-80°C.

[0016] Furthermore, the method also includes a step S3 for purifying the product, specifically: extracting the reaction solution obtained after sulfonation in step S2, collecting the lower aqueous phase, and drying it.

[0017] Furthermore, the solvent used for the extraction is petroleum ether.

[0018] Thirdly, embodiments of the present invention also provide an application of the novel compound as a mineral collector, wherein the mineral is a high-alkali calcium-containing mineral, and the high-alkali calcium-containing mineral contains scheelite, calcium molybdate, calcite and fluorite.

[0019] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects: 1. Compared with existing fatty acid collectors, the compound provided by this invention (which can be used as a collector molecule) is dumbbell-shaped, with sulfonic acid groups and carboxylic acid groups located at both ends of the carbon chain. Both can bind to the mineral surface through chemical adsorption, and the adsorption mode of the mineral exhibits mixed characteristics, that is, the carboxylic acid group and sulfonic acid group can jointly form a bidentate chelate, or they can adsorb separately. The specific form can be adjusted according to the mineral surface characteristics and / or the concentration of addition, resulting in higher adsorption density and stronger adsorption stability. At low concentrations, the compound provided by this invention (which can be used as a collector molecule) adopts a "flat" configuration to achieve two-point anchoring, resulting in strong adsorption. The hydrophobic alkyl chains are arranged parallel to the mineral surface, preventing the formation of a dense hydrophobic layer, but covering a large area. At high concentrations, similar to traditional collectors, the molecules adsorbed on the mineral surface are mainly in an "upright" configuration—the hydrophobic chains extend outward perpendicular to the surface, while some are adsorbed in a "flat" manner. This mixed adsorption method can form a highly ordered and dense hydrophobic layer. Furthermore, because the collector of this invention is fixed at both ends, the formed hydrophobic layer is even denser and more ordered. This ordered arrangement can significantly increase the contact angle of the mineral surface, thereby improving the flotation rate and recovery rate. The carboxylic acid group and the sulfonic acid group are spatially separated by an alkyl chain with a fixed spacing (approximately the length of the alkyl chain). This structure has molecular recognition ability for minerals with certain specific crystal plane spacings (such as partially oxidized minerals, rare earth minerals, fluorite, scheelite, etc.). The two functional groups can simultaneously adsorb onto two adjacent metal ion sites on the same mineral surface, forming a stable ring structure (although separated by an alkyl chain, it is actually a "two-point adsorption" or "bridging"). The stability of this ring chelate is much higher than that of single-point adsorption. For example, when the alkyl carbon chain contains 10 carbon atoms, during the flotation of low-grade tungsten-molybdenum ore (with gangue calcite), more stable adsorption can be achieved on the target minerals (scheelite, calcium molybdate), while the adsorption on gangue is weaker.

[0020] 2. The compound provided by this invention, as a collector molecule, is a multifunctional collector. Compared with traditional collectors, it contains both carboxyl and sulfonic acid groups. The introduction of amphiphilic groups significantly improves the water solubility of the agent. Specifically, the carboxylic acid group can undergo strong chemisorption with calcium ions, ensuring strong collecting ability; the sulfonic acid group can improve the water solubility and steric hindrance effect of the agent, enhancing selectivity, while effectively overcoming the limitations of traditional fatty acid collectors such as poor tolerance in hard water and poor low-temperature dispersibility.

[0021] 3. The preparation process of the compound (which can be used as a collector molecule) provided by this invention is simple, requires no catalyst, and has mild reaction conditions and readily available raw materials. By selecting a suitable reaction sequence, controlling a reasonable reactant ratio and reaction temperature, the synthesis rate of the collector can be ensured, while reducing side reactions, making it suitable for large-scale production.

[0022] 4. The compound provided by this invention (which can be used as a collector molecule) can be applied to the flotation of high-alkali calcium-containing target minerals. By adjusting the concentration of the collector molecule and the pH of the pulp to be flotated, the flotation and separation of high-alkali calcium-containing minerals can be achieved.

[0023] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0024] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0025] Figure 1 shows the general chemical structural formula of the compound of the present invention; Figure 2 The infrared spectrum of the collector molecule Z-SDMS of this invention; Figure 3 This is the mass spectrum of the Z-SDMS molecule of the collector of this invention; Figure 4 The surface tension isotherm curve of the collector molecule Z-SDMS of this invention; Figure 5 The synthesis reaction process of the collector molecule Z-SDMS of this invention; Figure 6 The flowchart shows a single mineral flotation process using the collector of this invention. Figure 7 The graph shows the effect of the collector Z-SDMS of the present invention on the single mineral flotation separation of scheelite, calcium molybdate and calcite as a function of pH. Figure 8 This is a graph showing the effect of the Z-SDMS collector dosage of the present invention on the single mineral flotation separation effect of scheelite, calcium molybdate and calcite. Figure 9 A flowchart illustrating the flotation of low-grade tungsten-molybdenum ore using the collector of this invention; Figure 10 This is the X-ray diffraction pattern of the low-grade tungsten-molybdenum ore of this invention. Detailed Implementation

[0026] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0027] In the field of tungsten and molybdenum mineral processing, with the increasing depletion of easily processed resources, current mineral resources generally exhibit characteristics of being "poor, fine-grained, and complex," posing a severe challenge to mineral processing and separation technologies. A core challenge lies in the extreme similarity in crystal structure, surface electrical properties, and solubility between the target minerals scheelite and calcium molybdate and associated calcium-bearing gangue minerals such as calcite and fluorite. This high degree of similarity in physicochemical properties leads to convergent interfacial behavior during flotation, resulting in poor selectivity in traditional separation methods based on differences in surface properties. This has long been a core technical challenge of low separation efficiency and low recovery rates.

[0028] Currently used collectors for the flotation of calcium gangue minerals, such as fatty acid collectors, hydroxamic acid collectors, and phosphorus-containing collectors, have problems such as low target concentrate grade and recovery rate, reliance on large amounts of modifiers in the process, high cost, and environmental pollution. These problems not only increase economic and environmental pressures, but also easily cause excessive inhibition of target minerals, which is not conducive to industrial promotion and application.

[0029] Therefore, embodiments of the present invention provide a novel compound with the general structural formula NaO3S-CH(CH3)-(CH2). n-2 -O-CO-CH=CH-COONa, such as Figure 1 As shown, where n = 8, 10~16.

[0030] Compared with existing compounds containing both sulfonic acid and carboxylic acid groups, the new compound provided by this invention has a dumbbell-shaped molecular structure, with the sulfonic acid and carboxylic acid groups located at opposite ends of the carbon chain. When used as a mineral collector, both groups can bind to the mineral surface through chemisorption, exhibiting a mixed adsorption mode. That is, the carboxylic acid and sulfonic acid groups can form bidentate chelates together or adsorb separately. The specific form can be adjusted according to the mineral surface characteristics and / or the concentration of the additive, resulting in higher adsorption density and stronger adsorption stability.

[0031] The carboxylic acid group and sulfonic acid group described in this invention are spatially separated by alkyl chains with a fixed spacing (approximately the length of the alkyl chain). This structure has molecular recognition capability for minerals with certain specific crystal plane spacings (such as partially oxidized minerals, rare earth minerals, fluorite, scheelite, etc.). The two functional groups can simultaneously chelate with two adjacent metal ion sites on the same mineral surface to form a stable ring structure (although separated by alkyl chains, it is actually a "double-point chelation" or "bridging"). The stability of this ring chelate is much higher than that of single-point adsorption. For example, when the alkyl carbon chain contains 10 carbon atoms, it can achieve more stable adsorption on the target minerals (scheelite, calcium molybdate) during the flotation of low-grade tungsten-molybdenum ore (associated with gangue calcite), while the adsorption on calcium-containing gangues (such as calcite, fluorite) is weaker.

[0032] It should be noted that, in order to balance the mineral-collecting performance and selectivity of the compound, the present invention needs to limit the length of the alkyl chain between the carboxylic acid group and the sulfonic acid group.

[0033] Specifically, in the general structural formula of the new compound, the number of carbon atoms n in the alkyl chain can be 8, 10, 11, 12, 13, 14, 15, or 16, preferably 10 to 12. If the number of carbon atoms is too small, the compound will not be hydrophobic enough and will not be able to effectively push away the hydration film on the mineral surface, resulting in weak collecting ability, high dosage, and poor foaming properties. However, if the carbon chain is too long, the molecules will have low solubility and poor dispersibility in the slurry, which will reduce the collecting efficiency and result in poor selectivity, making it easy for non-target minerals to float.

[0034] According to some preferred embodiments of the present invention, the alkyl chain has n=10 carbon atoms, corresponding to the compound (Z)-4-oxo-4-[(9-sulfonyldecyl)oxy]-2-butenoate sodium (Z-SDMS), with the structural formula as follows: Among them, Z-SDMS has a high adsorption selectivity for scheelite and is suitable for flotation of complex low-grade tungsten-molybdenum ores with high alkali and calcium ion content.

[0035] The critical micelle concentration (CMC) of the novel compound of this invention is lower than that of sodium oleate. For example... Figure 4 As shown, the CMC value was as low as 0.48 mmol / L.

[0036] Critical micelle concentration (CMC) is one of the core characteristic parameters of surfactants. A lower CMC value indicates higher surface activity, meaning the surfactant can form micelles at lower concentrations, thus more efficiently performing solubilizing and emulsifying functions. In practical applications, this translates to lower reagent dosages and greater economic efficiency. Existing literature reports that sodium oleate has a CMC of 0.962 g / L (equivalent to a molar concentration of 3.16 mmol / L), while the CMC of the Z-SDMS of this invention is 0.48 mmol / L (e.g., ...). Figure 4 As shown in the figure, the values ​​are all far lower than the CMC value of sodium oleate, indicating that the agent can reach the CMC at a lower concentration and exhibits a more superior surface activation ability.

[0037] The present invention also provides a method for preparing a new compound, the method comprising the following steps: S1: Esterification reaction of unsaturated fatty alcohol and maleic anhydride to obtain maleic acid monoalkenyl ester; S2: The maleic acid monoalkenyl ester is subjected to a sulfonation reaction with a reagent.

[0038] This invention uses maleic anhydride to react with unsaturated fatty alcohols and sulfonating agents in a two-step reaction of esterification and sulfonation to prepare compounds in which the sulfonic acid group and the carboxylic acid group are located at both ends of the carbon chain.

[0039] It should be noted that, in order to ensure that the highly active sulfonic acid group and carboxyl group in the final compound are located at both ends of the water-conducting carbon chain, the present invention limits the unsaturated fatty alcohols participating in the esterification reaction to terminal olefin primary alcohols.

[0040] Specifically, in step S1, the unsaturated fatty alcohol is at least one of 7-octen-1-ol, 9-decaeno-1-ol, 10-undecen-1-ol, 11-dodecen-1-ol, 12-tridecenol, 13-tetradecenol, 14-pentadecenol, and 15-hexadecenol.

[0041] More preferably, the unsaturated fatty alcohol is specifically 9-decaeno-1-ol.

[0042] It should be noted that, in order to ensure the complete esterification reaction and avoid the generation of byproducts such as diesters and polyesters, the present invention needs to limit the ratio of unsaturated fatty alcohols and maleic anhydride.

[0043] Specifically, in step S1, the molar ratio of the unsaturated fatty alcohol to maleic anhydride is 1:(1.00~1.10), which can be 1:1.00, 1:1.01, 1:1.02, 1:1.03, 1:1.04, 1:1.05, 1:1.06, 1:1.07, 1:1.08, 1:1.09, or 1:1.10, preferably 1:1.05. An appropriate excess of anhydride can drive the reaction forward, ensuring complete reaction of the unsaturated fatty alcohol and avoiding the production of byproducts such as diesters and polyesters from excess alcohol.

[0044] It should be noted that, in order to increase the esterification reaction rate while avoiding the formation of byproducts, the present invention requires limiting the temperature and time of the esterification reaction.

[0045] Specifically, in step (1), the temperature of the esterification reaction is 70~80℃, which can be 70℃, 72℃, 75℃, 78℃, or 80℃. If the temperature of the esterification reaction is too low, it may lead to problems such as a slower reaction rate or incomplete reaction. If the temperature is too high, some carboxyl molecules may form a dimer or generate a diester during the esterification process.

[0046] Specifically, in step (1), the esterification reaction time is 2-3 hours, which can be 2 hours, 2.3 hours, 2.5 hours, 2.7 hours, or 3 hours. If the reaction time is too short, the reaction will be incomplete, and if the time is too long, the product may decompose.

[0047] According to some preferred embodiments of the present invention, under stirring, a certain amount of 9-decaeno-1-ol is first heated to 70~80°C and the stirring speed is controlled at 500~600 r / min; then the weighed maleic anhydride is added in batches to the heated 9-decaeno-1-ol solution, and the reaction continues for 2~3 h after the addition is completed to prevent the generation of by-products due to large changes in reaction temperature.

[0048] Specifically, in step S2, the reagent is at least one of sodium sulfite, sodium bisulfite, potassium sulfite, sodium metabisulfite, and potassium metabisulfite.

[0049] More preferably, the sulfonating agent is sodium sulfite.

[0050] Specifically, in step S2, the molar ratio of the maleic acid monoalkenyl ester to the sulfonate group in the reagent is 1:(1.00~1.10), which can be 1:1.00, 1:1.01, 1:1.02, 1:1.03, 1:1.04, 1:1.05, 1:1.06, 1:1.07, 1:1.08, 1:1.09, or 1:1.10, preferably 1:1.05. An appropriate excess of sodium sulfite can ensure complete sulfonation of the intermediate and avoid an increase in side reactions.

[0051] It should be noted that, in order to improve the uniformity of the sulfonation reaction, avoid the intensity of local reactions, reduce temperature differences, and avoid side reactions, the present invention needs to limit the method of adding the reagents used to carry out the sulfonation reaction.

[0052] Specifically, the reagent is dissolved in deionized water, the concentration is controlled at 0.05-0.15 g / ml, and preheated to 70-80℃; then the preheated reagent solution is added dropwise to the maleic acid monoalkenyl ester obtained in step (1), and then sulfonation reaction is carried out.

[0053] Specifically, the sulfonation reaction temperature in step (2) is 70~80℃, which can be 70℃, 72℃, 75℃, 78℃, or 80℃; while increasing the reaction rate, side reactions caused by excessively high temperature are avoided.

[0054] Specifically, the sulfonation reaction time in step (2) is 2 to 3 hours, which can be 2 hours, 2.3 hours, 2.5 hours, 2.7 hours, or 3 hours. If the reaction time is too short, the reaction will be incomplete, and if the time is too long, the product may decompose.

[0055] Specifically, in order to promote the uniform and sufficient sulfonation reaction of maleic acid monoalkenyl ester and reduce the side reactions caused by excessive local reaction, during the sulfonation reaction in step (2), the stirring is continuously carried out at a rate of 600-900 r / min, which can be 600 r / min, 650 r / min, 700 r / min, 750 r / min, 800 r / min, 850 r / min, or 900 r / min.

[0056] According to some preferred embodiments of the present invention, the chemical reaction equation for preparing sodium (Z)-4-oxo-4-[(9-sulfonyldecyl)oxy]-2-butenoate (Z-SDMS) is as follows: Figure 5 As shown.

[0057] It should be noted that the method further includes step S3 of purifying the product.

[0058] Specifically, step S3 includes: extracting the reaction solution obtained after sulfonation in step S2, collecting the lower aqueous phase, and drying it.

[0059] More specifically, the solvent used for the extraction is petroleum ether.

[0060] According to some preferred embodiments of the present invention, the Z-SDMS solution obtained by sulfonation reaction in step 2 is taken, petroleum ether is added and mixed and stirred, then transferred to a separatory funnel and allowed to stand for separation and the lower aqueous phase is collected; the above operation is repeated 3 to 5 times; the lower aqueous phase solution is dried to obtain Z-SDMS powder.

[0061] This invention uses infrared spectroscopy and high-resolution mass spectrometry to detect the obtained compound (such as Z-SDMS) powder. By obtaining the functional groups corresponding to the characteristic peaks in the spectra, the structure of the obtained product can be obtained, such as... Figure 2 , 3 As shown.

[0062] The present invention also provides an application of the novel compound as a mineral collector, wherein the mineral is a high-alkali calcium-containing mineral, and the high-alkali calcium-containing mineral contains scheelite, calcium molybdate, calcite and fluorite.

[0063] Preferably, the high-alkali calcium-containing mineral is a low-grade tungsten-molybdenum ore, and the compound with multiple functional groups is Z-SDMS.

[0064] Preferably, the new compound can also be used for the flotation of zinc oxide ore and copper oxide ore.

[0065] According to some preferred embodiments of the present invention, an application of a collector in the flotation of high-alkali calcium-containing minerals is provided, employing a flotation process that first selects sulfide minerals and then selects oxide minerals, as shown in the following flow chart. Figure 9As shown, the specific steps include: (1) Grinding: crushing and grinding; (2) Adding reagents: First, perform flotation of sulfide ore by adding 900~2000 g / t of sodium carbonate, 3500~4000 g / t of water glass, and 200~260 g / t of collector kerosene to the slurry and stirring for 2~4 min; then add 16~20 g / t of frother MIBC and stir for 1~3 min; after stirring, aerate and perform flotation for 4~5 min, at which time the pH of the slurry is 8.5-9.5; then perform flotation of oxidized ore by adding 50~200 g / t of collector Z-SDMS and stirring for 2~4 min; then aerate and perform flotation for 4~5 min, thereby separating the concentrate and tailings. (3) Filter, dry and weigh the concentrate and tailings respectively, and calculate the yield and recovery rate.

[0066] Specifically, in step (1), after crushing and grinding, the particle size of 80wt% of the minerals is within the range of -74μm; by crushing and grinding, the surface area of ​​the ore is increased, which is beneficial to the contact and reaction between the reagents and the minerals in the subsequent flotation process, thereby improving the flotation efficiency; by controlling the particle size of the minerals within a certain range, the minerals are ensured to reach the optimal flotation conditions, thereby improving the selectivity and efficiency of flotation and reducing mechanical entrainment.

[0067] Specifically, in step (2), the stirring rate is 1990~1995 r / min, preferably 1992 r / min.

[0068] Preferably, in step (2), sodium carbonate is mainly used to adjust the pH value during the flotation process, and at the same time plays a role in dispersing the slurry; the tungsten molybdenum oxide collector has a good separation effect on valuable minerals and gangue minerals in the pH range of 7 to 11.

[0069] Compared with traditional collectors, the multifunctional collector of this invention contains both carboxyl and sulfonic acid groups in its molecule. The introduction of amphiphilic groups significantly improves the water solubility of the agent. Specifically, the carboxylic acid group can undergo strong chemisorption with calcium ions, ensuring strong collecting ability; the sulfonic acid group improves the water solubility and steric hindrance effect of the agent, enhancing selectivity, while effectively overcoming the limitations of traditional fatty acid collectors such as poor tolerance in hard water and poor dispersibility at low temperatures.

[0070] Preferably, in step (2), the amount of sodium carbonate added can be 900 g / t, 1000 g / t, or 1100 g / t, preferably 1000 g / t; the amount of water glass added can be 3500 g / t, 3800 g / t, 3900 g / t, or 4000 g / t, preferably 4000 g / t; the amount of kerosene added can be 200 g / t, 220 g / t, 240 g / t, 250 g / t, or 260 g / t, preferably 250 g / t; the amount of foaming agent MIBC added can be 16 g / t, 17 g / t, 18 g / t, 19 g / t, or 20 g / t, preferably 20 g / t; and the amount of tungsten-molybdenum oxide collector added can be 50 g / t, 60 g / t, 70 g / t, 80 g / t, 90 g / t, 100 g / t, or 105 g / t. g / t, 110 g / t, 120 g / t, 130 g / t, 140 g / t, 150 g / t, 160 g / t, 170 g / t, 180 g / t, 190 g / t, 200 g / t.

[0071] Specifically, in step (3), the drying temperature is 60~80 ℃ and the drying time is 12~14 h.

[0072] Compared with existing flotation methods, the collector molecules used in the flotation method of this invention have a dumbbell-shaped structure, with sulfonic acid groups and carboxylic acid groups located at both ends of the carbon chain. Both can bind to the mineral surface through chemical adsorption, and the adsorption mode of the mineral exhibits mixed characteristics. That is, the carboxylic acid groups and sulfonic acid groups can form bidentate chelates together, or they can adsorb separately. The specific form can be adjusted according to the mineral surface characteristics and / or the concentration of additives, resulting in higher adsorption density and stronger adsorption stability. Specifically, at low concentrations, the collector molecules of this invention adopt a "flat" configuration to achieve two-point anchoring, resulting in strong adsorption. The hydrophobic alkyl chains are arranged parallel to the mineral surface, preventing the formation of a dense hydrophobic layer, but covering a large area. At high concentrations, similar to traditional collectors, the molecules adsorbed on the mineral surface become "upright," meaning the hydrophobic chains extend outwards perpendicular to the surface, forming a highly ordered and dense hydrophobic layer. However, because the collector of this invention is fixed at both ends, the formed hydrophobic layer is even denser and more ordered. This ordered arrangement can significantly increase the contact angle of the mineral surface, improving the flotation rate and recovery rate. The carboxylic acid group and sulfonic acid group are spatially separated by an alkyl chain with a fixed spacing (approximately the length of the alkyl chain). This structure enables molecular recognition of minerals with specific interplanar spacings (such as scheelite, calcium molybdate, and calcite). The two functional groups can simultaneously chelate with two adjacent metal ion sites on the same mineral surface, forming a stable cyclic chelate. The stability of this cyclic chelate is much higher than that of single-point adsorption. For example, the alkyl carbon chain in Z-SDMS contains 10 carbon atoms. During the flotation of low-grade tungsten-molybdenum ore (with gangue calcite), it can achieve selective and stable adsorption on the target minerals (scheelite and calcium molybdate). Under optimal conditions (pH=9), the recoveries can reach over 95% and 73%, respectively, while the adsorption on gangue is weaker, below 40%.

[0073] The preparation and application of the new compounds of the present invention will be described below with reference to specific embodiments and comparative examples.

[0074] The purity of 9-decaeno-1-ol is 95%; the purity of anhydrous sodium sulfite is 98%.

[0075] Example 1 A method for preparing a compound (Z)-4-oxo-4-[(9-sulfonyldecyl)oxy]-2-butenoate sodium (Z-SDMS) includes the following steps: S1: Add 18.75 mL of 9-decaen-1-ol to a 500 mL four-necked flask equipped with a stirrer, thermometer and spherical condenser, and heat to 75 °C with a stirring rate of 500 r / min. While stirring, 10.34 g of maleic anhydride was added in portions to a 9-decaeno-1-ol solution. After the addition was complete, the reaction continued for 2.5 h to obtain maleic acid monoalkenyl ester. S2: Weigh 13.50 g of anhydrous sodium sulfite and dissolve it in 150 ml of deionized water. Heat the solution to 75 °C with a stirring rate of 500 r / min for preheating. Slowly add the preheated sodium sulfite solution dropwise to the maleic acid monoalkenyl ester obtained in step S1 through a constant pressure titration funnel. Add the solution dropwise while stirring vigorously at a rate of 800 r / min. Keep the solution at 75 °C and react for 2.5 h to obtain a reaction solution containing Z-SDMS. S3. After the reaction is complete, take 40 mL of the reaction system and mix it with 20 mL of petroleum ether (the ratio of the reaction system to petroleum ether is 2:1), extract 5 times, collect the transparent liquid at the bottom of the separatory funnel, and dry it at 60 °C to obtain the Z-SDMS product.

[0076] The infrared spectrum of the Z-SDMS product is as follows: Figure 2 As shown, it can be seen that: 2925.70 cm -1and 2850.17 cm -1 The characteristic peak at 1601.39 cm⁻¹ can be attributed to the stretching vibrations of -CH₃ and -CH₂. -1 and 1395.61 cm -1 The characteristic peaks at these locations are respectively generated by -COO - Caused by antisymmetric and symmetric stretching vibrations, 1173.21 cm -1 and 1040.18 cm -1 The characteristic peak at this location is the stretching vibration peak of -SO3Na. The characteristic absorption peak appearing in the infrared spectrum is consistent with the characteristic peak in the expected molecular structure, which can preliminarily confirm the successful synthesis of Z-SDMS; Figure 3 The mass spectrometry results using ESI as the ionization source (solvent: pure water; mode: negative ion) are shown. [M-2Na] appears in the results. + H] - or [M-Na] - The addition ion peak (M is the unionized product molecule) indicates that Z-SDMS was successfully synthesized.

[0077] Example 2 The same preparation method as in Example 1 was used, except that in step S1, the amount of 9-decaen-1-ol added was 19.68 mL, and the other steps and parameters were the same. The final product was characterized by infrared spectroscopy and mass spectrometry. By appropriately changing the ratio of 9-decaen-1-ol to maleic anhydride to improve the conversion rate of 9-decaen-1-ol, Z-SDMS product can also be obtained.

[0078] Example 3 The same preparation method as in Example 1 was used, except that in step S1, the esterification reaction temperature was increased to 80°C, while the other steps and parameters were the same. The final product was characterized by infrared spectroscopy and mass spectrometry. By appropriately increasing the esterification reaction temperature and the reaction rate, Z-SDMS products can also be obtained.

[0079] Example 4 The same preparation method as in Example 1 was used, except that in step S2, the amount of anhydrous sodium sulfite added was 12.9 g, and the other steps and parameters were the same. The final product was characterized by infrared spectroscopy and mass spectrometry. By appropriately changing the ratio of anhydrous sodium sulfite to maleic acid monoalkenyl ester and improving the conversion rate of maleic acid monoalkenyl ester, Z-SDMS product can also be obtained.

[0080] Example 5 The same preparation method as in Example 1 was used, except that in step S2, the sulfonation reaction temperature was reduced to 70°C, while the other steps and parameters remained the same. The final product was characterized by infrared spectroscopy and mass spectrometry. By appropriately reducing the esterification reaction temperature and increasing the reaction rate, Z-SDMS products can also be obtained.

[0081] Verification Example 1 Single mineral flotation experiments were conducted using scheelite, calcium molybdate, and calcite samples with a purity of over 96%. The single mineral samples were then manually sorted, crushed, ground, and sieved in sequence, and minerals with a particle size of 38–74 μm were selected for single mineral flotation experiments. The XFG type hanging cell flotation machine is used, with a main shaft speed of 1798 r / min and a flotation cell volume of 40 mL.

[0082] The process flow of single mineral flotation experiment is as follows: Figure 6 As shown, the specific steps include: S-1: Prepare the slurry: Weigh 2g of the ore sample to be treated, place it in a 40mL flotation cell, add 37mL of ultrapure water for slurry conditioning, and the conditioning time is 1 min. S-2: Adjusting the pH of the slurry: The pH of the slurry is adjusted to a predetermined value using sodium hydroxide and hydrochloric acid; S-3: Add collector: At room temperature, add collector Z-SDMS to the pH-adjusted slurry and stir continuously for 3 min to allow the collector to fully react with the mineral particles. S-4: Flotation separation: The slurry after the collector has acted is subjected to aerated flotation. The flotation time is controlled within 3 minutes. The collected froth product is the single mineral (scheelite, calcium molybdate or calcite) concentrate. S-5: Vacuum filter, dry and weigh the concentrate and tailings obtained in step S-4 respectively, and calculate the recovery rate. The drying temperature is 60℃ and the drying time is 12h.

[0083] When the concentration of the collector Z-SDMS is 2.0 × 10⁻⁶ -4 The recovery rate of a single mineral at mol / L as a function of pH is shown in the curve. Figure 7 As shown in the figure, the recovery rate of scheelite increases with increasing pH in the pH range of 7-9, reaching a peak of 96.98% at pH=9. However, the recovery rate decreases slightly (but remains above 87%) when the pH is between 9 and 11. This may be due to the high pH conditions caused by OH-. -As the concentration increased, competition for adsorption with the collector led to a decrease in recovery. The recovery rate of calcium molybdate showed a slow but steady upward trend, increasing from 63.07% to 73.53%. This is presumably due to the partial hydrolysis of Mo-O bonds on the surface of calcium molybdate at high pH, ​​generating more active sites that form more stable surface compounds with the sulfonic acid and carboxyl groups of Z-SDMS, thus improving its floatability. The recovery rate of calcite generally showed a downward trend, especially in the pH range of 7-9, decreasing significantly from 58.24% to 33.20%. The lowest recovery rate was observed at pH 10, possibly due to partial dissolution and reprecipitation of CaCO3 at this pH, or the poor stability of the complex formed by Z-SDMS, which inhibited its floatability. The flotation selectivity of the collector Z-SDMS for calcium-containing minerals, from highest to lowest, was: scheelite > calcium molybdate > calcite. When the pH value is 9, the recovery rates of the three minerals are 96.98% for scheelite, 73.03% for calcium molybdate, and 33.20% for calcite, which achieves the best separation effect.

[0084] When the pulp pH=9, the recovery rate of a single mineral as a function of the collector Z-SDMS concentration is shown in the curve below. Figure 8 As shown in the figure, it can be seen that with the increase of Z-SDMS dosage, the recovery rate of scheelite continuously increased, significantly from 82.78% to 95.72%, indicating that the adsorption behavior of scheelite on Z-SDMS has a significant concentration dependence. Increasing the dosage of the reagent helps to enhance its surface hydrophobicity and improve its floatability. The recovery rate of calcium molybdate showed little change with the increase of Z-SDMS concentration, remaining between 72.21% and 77.69%. At a concentration of 1.8 × 10⁻⁶, the recovery rate of calcium molybdate remained relatively stable. -4 The peak value appeared at mol / L, and subsequent increases in reagent concentration did not significantly improve its recovery rate. It is inferred that this may be because the surface adsorption active sites tend to be saturated, limiting further adsorption. The flotation recovery rate of calcite was consistently below 35%, and the fluctuation with reagent concentration was small, indicating that Z-SDMS has weak adsorption capacity on the calcite surface and is difficult to form a stable hydrophobic layer effectively. Even under high concentration conditions, it cannot significantly improve its floatability, indicating that the collector has good selective inhibition performance on calcite.

[0085] Experiments show that the collector provided by this invention exhibits good selective collection ability for oxidized tungsten-molybdenum ore in a wide pH range of 7 to 11, which can significantly improve its flotation recovery rate and achieve efficient separation from gangue minerals (such as calcite).

[0086] Application Example 1 This application example provides a method for actual mineral flotation using the collector prepared in Example 1. The process flow is as follows: Figure 9 As shown.

[0087] The flotation target is a low-grade tungsten-molybdenum ore from Henan Province. The X-ray diffraction (XRD) pattern of the raw ore is as follows: Figure 10 As shown, the analysis results indicate that the raw ore contains a large amount of fluorite, silicate and carbonate gangue minerals; molybdenum in the raw ore mainly exists in the form of sulfide mineral (molybdenite) and oxide mineral (calcium molybdate), while tungsten is present in the form of oxide mineral (scheelite).

[0088] The flotation process employing a method of first selecting sulfide ores and then selecting oxide ores is as follows: (1) Grinding: crushing and grinding to make the particle size of 80wt% of minerals within -74μm; (2) Addition of flotation reagents and flotation: First, sulfide ore flotation is carried out by adding 1000 g / t of sodium carbonate, 4000 g / t of water glass and 250 g / t of collector kerosene to the slurry and stirring for 3 min; then add 20 g / t of frother MIBC and stir for 2 min; after stirring, aeration is carried out for flotation, and the flotation time is 5 min, at which time the pH of the slurry is 9; then oxidized ore flotation is carried out by adding 100 g / t of collector Z-SDMS and stirring for 3 min; then aeration is carried out for flotation, and the flotation time is 5 min, thereby separating the concentrate product and tailings. (3) The concentrate and tailings were filtered, dried and weighed respectively, and the yield and recovery rate were calculated. The results are shown in Table 1.

[0089] Application Example 2 The same method as in Application Example 1 was used, except that the amount of collector in step (2) was reduced to 50 g / t; the final concentrate yield, recovery rate and grade results are shown in Table 1.

[0090] Application Example 2 The same method as in Application Example 1 was used, except that the amount of collector in step (2) was reduced to 200 g / t; the final concentrate yield, recovery rate and grade results are shown in Table 1.

[0091] Comparative Application Example 1 The same method as in Application Example 1 was used, except that the collector Z-SDMS in step (2) was replaced with sodium oleate; the final concentrate yield, recovery rate and grade results are shown in Table 1.

[0092] Table 1. Concentrate Flotation Results

[0093] Compared to the traditional collector sodium oleate, the collector Z-SDMS of this invention can achieve higher WO3 grade and recovery rate under the same reagent dosage, proving its superior flotation effect on low-grade, complex gangue mineral compositions of tungsten-molybdenum oxide ores. This is because sodium oleate relies on a single carboxyl group to interact with minerals, easily binding non-specifically to calcium-containing gangue. In contrast, the sulfonic acid and carboxylic acid groups in the Z-SDMS molecule are located at opposite ends of the carbon chain, exhibiting a mixed adsorption mode. The carboxylic acid and sulfonic acid groups can form bidentate chelates together or adsorb individually, the specific form depending on the mineral surface characteristics, thus achieving more stable adsorption on the target mineral and weaker adsorption on gangue.

[0094] The multifunctional surfactant provided by this invention has excellent selectivity, collecting ability and foaming ability. Its molecular structure includes carboxyl groups, sulfonic acid groups, ester groups and double bonds. Its collecting performance is significantly better than that of collectors in the prior art. It can adapt to the complex and low-grade flotation environment of tungsten-molybdenum oxide ore. It requires less reagent, is green and environmentally friendly, and its synthesis conditions are mild, making it suitable for large-scale production.

[0095] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A new compound, characterized in that, The general structural formula of the compound is NaO3S-CH(CH3)-(CH2). n-2 -O-CO-CH=CH-COONa, where n=8,10~16.

2. The compound according to claim 1, characterized in that, n is 10 to 12.

3. The compound according to claim 1, characterized in that, The compound is sodium (Z)-4-oxo-4-[(9-sulfonyldecyl)oxy]-2-butenoate, with the structural formula: .

4. A method for preparing the compound according to any one of claims 1-3, characterized in that, The method includes the following steps: S1: React unsaturated fatty alcohols and maleic anhydride to obtain maleic acid monoalkenyl ester; S2: The maleic acid monoalkenyl ester is subjected to a sulfonation reaction with a reagent.

5. The method according to claim 4, characterized in that, In step S1, the unsaturated fatty alcohol is specifically at least one of 7-octen-1-ol, 9-decaeno-1-ol, 10-undecen-1-ol, 11-dodecen-1-ol, 12-tridecenol, 13-tetradecenol, 14-pentadecenol, and 15-hexadecenol.

6. The method according to claim 4, characterized in that, In step S1, the molar ratio of the unsaturated fatty alcohol to maleic anhydride is 1:(1.00~1.10). And / or, the temperature of the reaction is 70~80℃.

7. The method according to claim 4, characterized in that, In step S2, the reagent is at least one of sodium sulfite, sodium bisulfite, potassium sulfite, sodium metabisulfite, and potassium metabisulfite. And / or, the sulfonation reaction is carried out at a temperature of 70~80°C.

8. The method according to claim 4, characterized in that, The method further includes a step S3 for purifying the product, specifically: extracting the reaction solution obtained after sulfonation in step S2, collecting the lower aqueous phase, and drying it.

9. The method according to claim 8, characterized in that, The solvent used for extraction is petroleum ether.

10. The use of a novel compound according to any one of claims 1-3 or a novel compound prepared by the method according to any one of claims 4-9 as a mineral collector, characterized in that, The mineral is a high-alkali calcium-bearing mineral, wherein the high-alkali calcium-bearing mineral contains scheelite, calcium molybdate, calcite and fluorite.

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