CN119565781A - A metal ion-nitrogen-containing aromatic heterocyclic complex collector and its preparation method and application in tungsten ore flotation - Google Patents

Abstract

The invention discloses a metal ion-nitrogen-containing aromatic heterocyclic complex collecting agent, a preparation method thereof and application thereof in tungsten ore floatation, and belongs to the technical field of ore dressing. The metal ion-nitrogen-containing aromatic heterocyclic complex collector is formed by assembling a hydroxamic acid group-containing nitrogen-containing aromatic heterocyclic ligand compound with the following molecular structure and divalent or more metal ions in a coordination manner: Compared with the existing Pb-BHA complex collector, the collector has stronger targeted adsorption and selective collection capacity and higher flotation rate for tungsten-containing minerals, can effectively strengthen the flotation of the tungsten-containing minerals, can particularly effectively realize the mixed flotation of various tungsten minerals with lower dosage, and greatly improves the comprehensive recovery rate of tungsten resources.

Description

Metal ion-nitrogenous aromatic heterocyclic complex collecting agent, preparation method thereof and application thereof in tungsten ore floatation

Technical Field

The invention relates to a metal ion-nitrogen-containing aromatic heterocyclic complex collector, a preparation method thereof and application thereof in tungsten ore floatation, and belongs to the technical field of ore dressing.

Background

Tungsten is known as an important strategic metal, namely "industrial teeth", and has been widely used in various fields such as military industry, civil use, industry, etc., because of its excellent series of physical and chemical properties. At present, with the increasing exhaustion of high-quality single black tungsten resources which are easy to reselect and separate, the characteristics of 'lean, thin, mixed and difficult' tungsten ore resources are gradually exposed, and single white tungsten ore deposit and black and white tungsten mixed ore deposit gradually become main objects of the development and utilization of the existing tungsten ore resources. The ore of the type is characterized by high content of calcium-containing gangue minerals, complex symbiotic relationship and finer embedding granularity, and the traditional process is more and more difficult to adapt to the change of ore properties, so that the production index is deteriorated year by year.

In recent years, pb-BHA complex collectors developed by university of south China realize normal-temperature mixed flotation of scheelite and scheelite to a certain extent, and realize successful industrial application in large-scale tungsten concentrating mills such as Hunan persimmon bamboo garden, yellow sand plateau, fujian Xinghui and the like. However, long-term production practice shows that in the mixed flotation process of scheelite and scheelite, the flotation behaviors of the scheelite and scheelite are different, most of tungsten minerals lost in tailings are scheelite, and the comprehensive recovery rate needs to be improved. For example, the grade of raw ore WO ₃ in a Hunan persimmon bamboo garden tungsten multi-metal mill is about 0.32%, and the mill is a typical complex low-grade tungsten molybdenum multi-metal black and white tungsten associated resource, wherein main tungsten-containing minerals are black and white tungsten ores and trace tungsten, the proportion of the black and white tungsten ores is about 3:7, the proportion of the white tungsten ores to the black tungsten ores in rough concentrate under a Pb-BHA flotation system is 3:1, the proportion of the white tungsten ores to the black tungsten ores in concentrate one is 5:1, the proportion of the white tungsten ores to the black tungsten ores in concentrate two is 6:1, the loss of the black tungsten ores in a concentration section is serious, the black tungsten ores run out more, and the flotation efficiency is not high.

In fact, the main reasons for the loss of the wolframite are poor floatability and low flotation rate, so that the wolframite falls into tailings under the action of a plurality of carefully selected inhibitors, and the key for strengthening the flotation recovery of the wolframite resources is the design and development of novel flotation agents. Compared with the modification of the process flows of reducing the number of fine separation sections, independently opening middlings, combining heavy flotation and the like, the development of the efficient flotation reagent is simpler and more effective, and the efficient flotation recovery can be realized on the premise of not reducing the grade of concentrate. For example, chinese patent (publication No. CN 111068926A) discloses a hydroxamic acid-alkylsulfate multi-ligand metal complex collector, which enhances the selective collection capacity of polar metal groups on tungsten minerals by introducing novel alkyl sulfuric acid ligands into the original metal ion-hydroxamic acid complex system, so as to improve the flotation recovery rate. For another example, chinese patent (publication No. CN 115228618A) discloses an O-allylsalicylic hydroxamic acid with good intramolecular synergism of the collector molecular structure and substituents, which essentially consists in modifying the hydrophobic structure of the collector ligand to improve the hydrophobicity of froth flotation.

In general, the novel tungsten ore flotation reagent at the present stage mainly comprises modification of hydrophobic groups in a hydroxamic acid molecular structure and development of multi-ligand collectors, and the collectors have obvious defects in the tungsten ore flotation process, such as poor floatability of wolfram nigricant, serious tailing caused by low flotation rate, low flotation efficiency and the like when a typical Pb-BHA complex is used in the normal-temperature mixed flotation process of wolfram nigricant.

Disclosure of Invention

Aiming at the technical problems of serious tailing leakage, low flotation efficiency and the like caused by poor floatability of wolframite and low flotation rate in the normal-temperature mixed flotation process of the black tungsten and the white tungsten of the Pb-BHA complex in the prior art, the first aim of the invention is to provide a metal ion-nitrogen-containing aromatic heterocyclic complex collector, wherein a nitrogen-containing aromatic heterocyclic ligand containing hydroxamic acid groups has a large conjugated system with condensed benzene rings and pyrrole, thereby improving the chelating capacity between chelating groups on the ligand and the metal ions, having larger adsorption capacity, higher adsorption strength and stability, having stronger selective collecting capacity for tungsten-containing minerals compared with the conventional Pb-BHA complex, being capable of strengthening the floatability and flotation rate of the black tungsten, and realizing the high-efficiency mixed flotation of the black tungsten.

The second object of the invention is to provide a preparation method of the metal ion-nitrogen-containing aromatic heterocyclic complex collector, which is simple to operate, mild in condition and low in cost, and is beneficial to expanding production.

The third purpose of the invention is to provide the application of the metal ion-nitrogen-containing aromatic heterocyclic complex collector, which is used for floatation of tungsten-containing minerals, has strong collecting capacity and good selectivity, can greatly improve the grade and recovery rate of floatation concentrate of tungsten-containing minerals, is particularly suitable for floatation of mixed tungsten minerals, has low use cost, and is favorable for further popularization and application.

In order to achieve the technical aim, the invention provides a metal ion-nitrogen-containing aromatic heterocyclic complex collector which is formed by assembling a nitrogen-containing aromatic heterocyclic ligand compound containing a hydroxamic acid group and more than divalent metal ions in a coordination manner:

the hydroxamate group-containing nitrogen-containing aromatic heterocyclic ligand compound has the structure of formula 1:

1 (1)

Wherein R ₁、R₂、R₃、R₄ or R ₅ is a hydroxamic acid group.

The metal ion-nitrogen-containing aromatic heterocyclic complex collector is obtained by optimally designing the molecular structure of a benzoic hydroxamic acid ligand on the basis of the traditional Pb-BHA complex collector. The key of the improvement of the p-benzohydroxamic acid ligand is that the benzene ring is replaced by the benzopyrrole, the benzopyrrole has a larger conjugated system relative to the benzene ring, and simultaneously nitrogen heterocycle is introduced. The pyrrole structure has stronger electron donating conjugation effect due to double bond and nitrogen heteroatom with stronger electronegativity, and has higher electron reactivity in delocalized pi bond formed by benzene ring, so that the bonding capability of hydroxyl oxygen and oximido oxygen which play a role in chelation on a conjugated system can be enhanced, and the method further shows better selectivity, stronger collecting capability and faster flotation rate. The metal ion-nitrogen-containing aromatic heterocyclic complex formed by assembling the nitrogen-containing aromatic heterocyclic complex containing hydroxamic acid groups with metal ions has larger colloid particle size compared with the conventional Pb-BHA complex, and nitrogen heteroatoms in the pyrrole structure are good hydrogen bond donors and contribute to intermolecular action, so that the adsorption strength and adsorption density of the collector on the surface of the target mineral are larger, the surface roughness of the collector can be obviously improved, the hydrophilic-hydrophobic difference between the target mineral and the gangue mineral surface is enhanced, and the efficient co-enrichment of the target mineral is more facilitated.

As a preferred embodiment, the divalent or more metal ions include at least one of Pb ²⁺、Ca²⁺、Mg²⁺、Cu²⁺、Mn²⁺、Fe²⁺、Al³⁺ or Fe ³⁺. The metal ion-nitrogen-containing aromatic heterocyclic complex collector formed by assembling different metal ions with the nitrogen-containing aromatic heterocyclic ligand compound containing the hydroxamic acid group has different flotation capacities, and the more preferable divalent or more metal ion is Pb ²⁺. Because the radius of the bivalent lead ion is 1.2A, the bivalent lead ion has larger polarizability, and the out-of-core electrons are distributed as [ Xe ]4f ¹⁴5d¹⁰6s², the electrons existing in the d and f orbitals of the lead ion cannot effectively shield the s electrons of the valence layer, the unique property is also endowed, and the coordination regulation and assembly effect at the mineral flotation interface is particularly remarkable.

As a preferable scheme, the coordination mole ratio of the nitrogen-containing aromatic heterocyclic ligand compound containing the hydroxamic acid group and the metal ions with more than two valences is (1-16): 1-4. The divalent or more metal ions and the nitrogen-containing aromatic heterocyclic ligand compound containing hydroxamic acid groups are subjected to coordination reaction in advance to generate a relatively stable metal ion-nitrogen-containing aromatic heterocyclic complex, and the complex is a mixture of various metal ion-nitrogen-containing aromatic heterocyclic complexes, has relatively complex components, and has the effect on the mineral surface represented by the synergistic effect of various physical adsorption and chemical adsorption. The proportion of the nitrogen-containing aromatic heterocyclic ligand compound containing the hydroxamic acid group to the divalent or more metal ions can influence the spatial structure of the complex, and the control of the metal ions in a proper range is beneficial to exerting the template effect of the metal ions, but if the content of the metal ions is too high, silicate gangue minerals such as quartz, garnet and the like can be activated, and meanwhile, the foam viscosity is increased, the fluidity is poor, and the foam enrichment state is seriously deteriorated. The coordination mole ratio of the nitrogen-containing aromatic heterocyclic ligand compound containing the hydroxamic acid group to the metal ions with more than two valencies is more preferably (6-12): 1-2.

The invention also provides a preparation method of the metal ion-nitrogen-containing aromatic heterocyclic complex collector, which is to stir and react a hydroxamic acid group-containing nitrogen-containing aromatic heterocyclic ligand compound solution with a divalent or more metal salt solution under an alkaline condition to obtain the metal ion-nitrogen-containing aromatic heterocyclic complex collector.

As a preferable scheme, the stirring reaction condition is that the stirring speed is 200-2000 r/min, the pH is 8.0-10.0, the temperature is 10-50 ℃ and the time is 1-20 min. The pH of the coordination reaction is controlled to be 8.0-10.0, most of divalent metal ions exist in the form of a hydroxyl complex, the introduction of hydroxyl is helpful for regulating and controlling the molecular structure of the assembled complex, and the hydration barrier of hydroxamic acid action during the pre-activation is overcome in advance, but the excessive pH can cause the hydroxide precipitation to be generated, so that the absorption of the hydroxide on the mineral surface is hindered. The divalent or higher metal salt solution is mainly provided by soluble metal salts, such as nitrate, chloride salts.

The nitrogen-containing aromatic heterocyclic organic compound is prepared by the following method:

1) Preparing free hydroxylamine by adding proper amount of sodium hydroxide into hydroxylamine hydrochloride to obtain free hydroxylamine, filtering to remove sodium chloride solid generated by the reaction to obtain hydroxylamine alkali solution;

2) The hydroximization reaction is carried out by mixing organic carboxylic ester compound with hydroxylamine alkali solution according to a certain proportion, controlling reaction condition to be alkaline, and carrying out hydroximization reaction at proper temperature to obtain corresponding hydroximic acid salt;

the organic carboxylic ester compound has a structure of formula 2:

2, 2

Wherein R ¹、R²、R³、R⁴ or R ⁵ is a carboxylate group;

3) And (3) acidizing reaction, namely adding concentrated sulfuric acid or concentrated hydrochloric acid into an oximation system to perform acidizing reaction, so as to obtain the nitrogen-containing aromatic heterocyclic ligand compound containing hydroxamic acid groups.

The invention also provides application of the metal ion-nitrogen-containing aromatic heterocyclic complex collector, which is used as the collector for flotation separation of tungsten-containing minerals.

As a preferred embodiment, the tungsten-containing mineral includes at least one of wolframite, scheelite, and tungsten bloom. The tungsten-containing mineral may be a mixed tungsten-containing mineral of a plurality of minerals, such as black-and-white mixed tungsten ore, or the like.

As a preferable scheme, the tungsten-containing mineral is subjected to grinding, iron removal and desulfurization pretreatment to obtain desulfurization tailing pulp, and after the desulfurization tailing pulp is subjected to size mixing, tungsten ore floatation is carried out by adopting a floatation reagent containing a metal ion-nitrogen-containing aromatic heterocyclic complex collector and a salinized water glass inhibitor to obtain tungsten concentrate.

As a preferable scheme, the concentration of the desulphurized tailing pulp is adjusted to 40-50wt%, and the pH is adjusted to 9.0-10.0. Sodium carbonate is used for pH adjustment.

The tungsten ore flotation method comprises 1 roughing, more than 2 carefully selecting and more than 2 scavenging, wherein the roughing agent system comprises 300-600 g/t of metal ion-nitrogen-containing aromatic heterocyclic compound collecting agent and 30-50 g/t of No. 2 oil foaming agent, the carefully selecting agent system comprises 50-500 g/t of salinized water glass inhibitor and follows a halving principle, the salinized water glass consists of aluminum sulfate and water glass according to the mass ratio of 1 (2-4) of aluminum sulfate to water glass, the scavenging agent system comprises 0-20 g/t of No. 2 oil foaming agent, and the mass of the metal ion-nitrogen-containing aromatic heterocyclic compound collecting agent is measured according to the mass of the nitrogen-containing aromatic heterocyclic compound. Under the preferable flotation reagent system, the flotation efficiency of tungsten-containing minerals, especially wolframite, can be effectively enhanced, the tail of tungsten is reduced, and the grade and recovery rate of final tungsten concentrate are improved.

The nitrogen-containing aromatic heterocyclic compound can be regarded as a hydroxidized modified product of indole, and indole and homologues and derivatives thereof widely exist in nature and mainly exist in natural flower oil, such as jasmine flower, bitter orange flower, narcissus flower, moldavica dragonhead and the like. In addition, it is also present in coal tar and spoiled proteins. Industrially, indole can be prepared by various methods, for example, extraction from high-temperature coal tar, and the steps of alkaline washing, acid washing, rectification, hydrolysis and the like of coal tar and wash oil fractions to obtain refined indole. At present, few reports of the compounds in the field of synthesis of flotation medicaments are provided, and the compounds have good application prospects.

The iron removal and desulfurization of the invention are conventional tungsten ore pretreatment processes in the prior art.

The salinized water glass is a conventional inhibitor for tungsten ore floatation in the prior art.

Compared with the prior art, the invention has the following beneficial technical effects:

(1) Compared with the existing Pb-BHA complex collector, the collector provided by the invention has stronger collecting capacity, better selectivity and higher flotation rate, the nitrogen-containing aromatic heterocyclic organic ligand is a conjugated system containing 10 pi electrons, and comprises a six-membered benzene ring and a five-membered nitrogen-containing pyrrole ring, the nitrogen atoms provide a pair of lone pairs of electrons to form a stable conjugated system, the whole shows stronger electron pushing effect, and the hydroxyoxy and oximido oxygen bonded with metal ions in the molecular structure of hydroxamic acid have stronger chelating capacity.

(2) The metal ion-nitrogen-containing aromatic heterocyclic complex collector provided by the invention can strengthen the flotation recovery of tungsten-containing minerals under a weak alkaline condition, has better selectivity, is beneficial to reducing black tungsten tailing, realizes the efficient mixed flotation of black tungsten, and improves the grade and recovery rate of final tungsten concentrate.

(3) The beneficiation method for recovering the tungsten polymetallic ore by utilizing the metal ion-nitrogen-containing aromatic heterocyclic complex collector through flotation provided by the invention has the advantages of simplicity in operation and low medicament cost, is suitable for various tungsten polymetallic ores such as single white tungsten and black-white tungsten mixed ores, and is beneficial to further popularization and application.

(4) The preparation method of the metal ion-nitrogen-containing aromatic heterocyclic complex has the advantages of high yield, less impurities, easily available raw materials, low cost and contribution to large-scale production.

Drawings

FIG. 1 is a nuclear magnetic resonance hydrogen spectrum of 1H-indole-7-hydroxamic acid according to the present invention.

Fig. 2 is an infrared spectrum of the lead-based complex collector of example 1.

FIG. 3 is a nuclear magnetic resonance hydrogen spectrum of 1H-indole-3-hydroxamic acid according to the present invention.

Fig. 4 shows the results of the pure mineral flotation test of example 3 and comparative example 1.

Fig. 5 is a flow chart of the flotation process of example 4.

Detailed Description

The following examples are presented to illustrate the invention in further detail and are not intended to limit the scope of the invention as claimed.

Example 1

Preparation of lead-based complex collectors:

50ml of methanol was added as a solvent to the flask, 10.42g of hydroxylamine hydrochloride (0.15 mol) having a purity of 98.5% was added to the flask with stirring, 12g of sodium hydroxide solid (0.3 mol) having a purity of 99% in total (3 g, 3g, 3g, 3 g) were added in portions after the hydroxylamine hydrochloride was dissolved, and the sodium chloride solid formed by the reaction was removed by filtration after stirring for 1 hour to obtain the free hydroxylamine base solution. Transferring the hydroxylamine alkali solution into a three-necked flask, adding 17.52g of 1H-indole-7-methyl formate (0.1 mol) with the purity of 97%, controlling the pH value of a reaction system to be about 12.0, starting a circulating condensation reflux system, and stirring for 4 hours at 55 ℃ to obtain the hydroxamation modified product. After the hydroximization reaction is finished, dropwise adding concentrated hydrochloric acid into a reaction system under the condition of room temperature while stirring, adjusting the pH value of the reaction system to be less than 5.0, preparing weak acid by using strong acid, filtering to remove generated filter residues after the dropwise adding is finished, and distilling the filtrate under reduced pressure to obtain a mauve solid, namely a crude 1H-indole-7-hydroximic acid product, wherein nuclear magnetic resonance 1H NMR is shown as a figure 1.

Adding 0.125mol of lead nitrate into 1L of 1H-indole-7-hydroxamic acid solution with the concentration of 1.0mol/L, controlling the stirring speed to be 1000r/min, adjusting the pH value to 9.0 by sodium hydroxide, and reacting for 3min at room temperature to obtain the lead-based complex collector, wherein the infrared spectrum of the lead-based complex collector is shown in figure 2.

Example 2

Preparation of iron-based complex collector:

30ml of methanol was added as a solvent to the flask, 1.042g of hydroxylamine hydrochloride (0.015 mol) having a purity of 98.5% was added to the flask with stirring, and after the hydroxylamine hydrochloride was dissolved, 1.2g of sodium hydroxide solid (0.03 mol) having a purity of 99% (0.3 g, 0.3g, 0.3g, 0.3 g) was added in portions in total, and after the reaction was stirred for 1 hour, sodium chloride solid formed by the reaction was removed by filtration to obtain the free hydroxylamine alkali solution. The hydroxylamine base solution was transferred to a three-necked flask, 1.7518g of 1H-indole-3-carboxylic acid methyl ester (0.01 mol) with a purity of 98% was added, the reaction conditions were controlled to be alkaline, a circulating condensation reflux system was turned on, and stirring was carried out at 50℃for 3 hours to obtain the hydroxamated modified compound. After the reaction is finished, dropwise adding concentrated sulfuric acid into a reaction system under the condition of room temperature while stirring, adjusting the pH value of the reaction system to 4.0-5.0, preparing weak acid by using strong acid, and after the dropwise adding is finished, performing reduced pressure distillation on filtrate to obtain an off-white solid, namely a 1H-indole-3 hydroxamic acid crude product, wherein the off-white solid can be further purified by adopting an ethanol and water recrystallization method, and the specific nuclear magnetic resonance 1H NMR is shown in figure 3.

Other compounds of the same type can be prepared synthetically by the method.

Adding 0.15mol of ferric chloride into 1L of 1H-indole-3 hydroxamic acid solution with the concentration of 1.0mol/L under the stirring condition, controlling the rotating speed to be 1200r/min, adjusting the pH value to 9.0 by sodium hydroxide, and reacting for 3min at room temperature to obtain the iron-based complex collector.

The metal ion-nitrogen-containing aromatic heterocyclic complex collectors used in the following specific examples were prepared by this method.

Example 3

Black and white tungsten flotation rate for novel lead-based complex collectors:

The novel lead-based complex collector described in example 1 was added in an amount of 5.0X10 ^-5 mol/L, the pH of the flotation slurry was adjusted to 9 with sodium hydroxide, the amount of methyl isobutyl carbinol (MIBC) as a foaming agent was 12.5. Mu.L/L, the flow rate of N ₂ was 300mL/min, and flotation was performed on scheelite with particle sizes of-0.074 to +0.038mm and scheelite with particle sizes of-0.038 mm, and the foam was scraped manually in batches using a scraper at a frequency of once every 5s, and collected once every 15 s.

Comparative example 1

Black and white tungsten flotation rate of Pb-BHA complex:

Adding a conventional Pb-BHA complex collector with the dosage of 5.0X10 ^-5 mol/L, regulating the pH value of flotation pulp to 9 by using sodium hydroxide, regulating the dosage of foaming agent methyl isobutyl carbinol (MIBC) to 12.5 mu L/L and the flow rate of N ₂ to 300mL/min, carrying out flotation operation on scheelite with the grain size of-0.074+0.038 mm and scheelite with the grain size of-0.038 mm, manually scraping foam in batches by using a scraper according to the frequency of once every 5s, and collecting foam once every 15 s.

As can be seen from FIG. 3, under the Pb-BHA system, the scheelite has better floatability and faster flotation rate, the cumulative recovery rate of the scheelite in the first 90s increases more, the scheelite is stable after that, and the final recovery rate reaches about 45%. Under the same conditions, the flotation efficiency of the scheelite is low, the flotation rate is low, and the final recovery rate is only about 20%, which also causes more scheelite to be lost in tailings in the scheelite mixed flotation process. The novel Pb-NHIC complex collector has stronger collecting capacity and faster flotation rate for wolframite and scheelite, the accumulated recovery rate of the wolframite and scheelite is balanced at about 60s, and the final recovery rate reaches more than 90%, which also shows that the novel metal ion-nitrogenous aromatic heterocyclic complex collector has better flotation performance.

Example 4

Black and white tungsten mixed flotation of novel lead-based complex collectors:

The specific process flow of treating some tungsten polymetallic ore in Hunan by the process method is shown in figure 4. The ore WO ₃ has grade 0.36%, wherein the ratio of black and white tungsten is 3:7, and gangue is mainly garnet, calcite and fluorite. Crushing and grinding raw ore, wherein the mass content of the raw ore meets more than 75% of a-200-mesh grade, then adopting a drum type wet magnetic separator, carrying out weak magnetic iron removal under the condition of magnetic field intensity of 0.4T, and carrying out desulfurization flotation on iron-removing tailings by taking 160g/T copper sulfate as an activating agent, 60g/T butyl xanthate and 40g/T ethionine as a collecting agent and 30 g/T2 # oil as a foaming agent. The pH value of ore pulp is adjusted to 9.0 through sodium carbonate, the lead-based complex collecting agent described in the embodiment 1 is added, the dosage is 450g/t, the foaming agent No. 2 oil is 40g/t, the pH value is stabilized to about 8.3 after the slurry is aerated and stirred for 5min, and the black-white tungsten mixed flotation roughing operation is carried out. The scavenging operation is to add 20g/t and 10g/t of No. 2 oil respectively, carefully select and add salinized water glass Al-SBL as inhibitor (the mass ratio of aluminum sulfate to water glass is 1:2), carefully select and use the salinized water glass Al-SBL with the total dosage of 150g/t. After four times of concentration, tungsten concentrate containing WO ₃ 31.51.51% is obtained, and the recovery rate is 78.22%.

Comparative example 2

Black and white tungsten mixed flotation of Pb-BHA complex collectors:

Adding 0.125mol of lead nitrate into 1L of 1.0mol/L of benzoic hydroxamic acid solution under the condition of stirring, and reacting for 3min at room temperature to obtain the Pb-BHA complex collector.

Comparative example 2 was used to compare with example 4, and the crushing, grinding, iron removal, desulphurisation and other procedures in comparative example 2 were identical to example 4, with the only difference that the roughing used a conventional Pb-BHA complex collector. The pH value of ore pulp is adjusted to 9.5 through sodium carbonate, the dosage of Pb-BHA complex collector is 600g/t, the dosage of foaming agent No. 2 oil is 40g/t, the pH value is stabilized to about 8.5 after the mixture is aerated and stirred for 5min, and black-white tungsten mixed flotation roughing operation is carried out. The scavenging operation is to add 20g/t and 10g/t of No. 2 oil respectively, carefully select and add salinized water glass Al-SBL as inhibitor (the mass ratio of aluminum sulfate to water glass is 1:2), carefully select and use the salinized water glass Al-SBL with the total dosage of 150g/t. After four times of concentration, tungsten concentrate containing WO ₃ 30.05.05% is obtained, and the recovery rate is 72.28%. According to the flotation test result, the novel metal ion-nitrogen-containing aromatic heterocyclic complex collector can achieve higher flotation efficiency under lower consumption, the grade of tungsten concentrate is improved from 30.05% to 31.51%, the recovery rate is improved from 72.28 to 78.22%, and the novel metal ion-nitrogen-containing aromatic heterocyclic complex collector has a good application prospect.

Example 5

Scheelite flotation of novel iron-based complex collectors:

The method is used for treating certain tungsten polymetallic ore in Hunan, the ore is single scheelite, the content of scheelite is extremely low, the tungsten grade of raw ore is about 0.18%, the fluorite content is higher, main gangue minerals mainly comprise calcite, garnet and quartz, the scheelite has uniform granularity, the main granularity range is 0.04-0.32 mm, and the method belongs to the fine-micro particle uniform embedding type. Crushing and grinding raw ore, wherein the mass content of the raw ore meets the grade of-200 meshes, then adopting a drum type wet magnetic separator, carrying out weak magnetic iron removal under the condition of magnetic field strength of 0.3T, concentrating a non-magnetic product by a thickener, adding 200g/T copper sulfate as an activating agent, 150g/T xanthate and 10g/T kerosene as a collecting agent, and 40g/T No. 2 oil as a foaming agent, and carrying out desulfurization flotation. The pH value of ore pulp of the desulphurized tailings is adjusted to 9.5 through carbonic acid ore, 600g/t of the iron-based complex collector described in the embodiment 2 is added, 40g/t of foaming agent No. 2 oil is added, the pH value is stabilized to be about 7.8 after the slurry is stirred for 5min by aeration, tungsten roughing operation is carried out, 20g/t of scavenging supplemental No. 2 oil is carried out, the total consumption of refined and added salinized sodium silicate Al-SBL (1:2) is 400g/t, and tungsten concentrate WO ₃ 45.33.33% and the recovery rate 70.51% are obtained after four times of concentration.

Comparative example 3

Scheelite flotation of Fe-BHA complex collectors:

Adding 0.15mol of ferric chloride into 1L of 1.0mol/L of benzoic hydroxamic acid solution under the stirring condition, and reacting for 3min to obtain the Fe-BHA complex collector. Comparative example 3 was conducted in comparison with example 5, in which the procedures of crushing, grinding, iron removal, desulfurization and the like were the same as in example 5, the pH of the slurry of the desulfurized tailings was adjusted to 9.0 by sodium carbonate, 800g/t of Fe-BHA complex collector was added, 40g/t of foaming agent 2# oil, the pH was stabilized at about 7.5 after 5min of aeration and size mixing, a tungsten roughing operation was conducted, 200g/t of Fe-BHA collector was added by scavenging, 10g/t of 2# oil was added, the total amount of added salted sodium silicate Al-SBL (1:2) was 400g/t, and tungsten concentrate WO ₃ 42.89.89% and recovery 67.69% were obtained after four rounds of concentration. The flotation test result shows that the novel metal-based complex collector can also realize flotation recovery of single scheelite, the consumption is lower, the concentrate grade and the recovery rate are higher, and the concentrate grade is improved by about 2.5 percent and the recovery rate is improved by about 3 percent under the condition of reducing the consumption by one fourth.

Claims (10)

1. A metal ion-nitrogen-containing aromatic heterocyclic complex collector, characterized in that it is assembled by coordination of a nitrogen-containing aromatic heterocyclic ligand compound containing a hydroxamic acid group and a divalent or higher metal ion: The nitrogen-containing aromatic heterocyclic ligand compound containing a hydroxamic acid group has a structure of Formula 1: Formula 1; Wherein, R ₁ , R ₂ , R ₃ , R ₄ or R ₅ is a hydroxamic acid group. 2. A metal ion-nitrogen-containing aromatic heterocyclic complex collector according to claim 1, characterized in that the divalent or higher valent metal ions include at least one of Pb ²⁺ , Ca ²⁺ , Mg ²⁺ , Cu ²⁺ , Mn ²⁺ , Fe ²⁺ , Al ³⁺ or Fe ³⁺ . 3. A metal ion-nitrogen-containing aromatic heterocyclic complex collector according to claim 1 or 2, characterized in that the coordination molar ratio of the nitrogen-containing aromatic heterocyclic ligand compound containing a hydroxamic acid group to the divalent or higher metal ion is (1-16): (1-4). 4. A method for preparing a metal ion-nitrogen-containing aromatic heterocyclic complex collector according to any one of claims 1 to 3, characterized in that a solution of a nitrogen-containing aromatic heterocyclic ligand compound containing a hydroxamic acid group and a solution of a divalent or higher metal salt are stirred and reacted under alkaline conditions to obtain the product. 5. The method for preparing a metal ion-nitrogen-containing aromatic heterocyclic complex collector according to claim 4, characterized in that the stirring reaction conditions are: a stirring rate of 200-2000 r/min, a pH of 8.0-10.0, a temperature of 10-50° C., and a time of 1-20 min. 6. Use of a metal ion-nitrogen-containing aromatic heterocyclic complex collector as claimed in any one of claims 1 to 3, characterized in that it is used as a collector for flotation separation of tungsten-containing minerals. 7. The use of a metal ion-nitrogen-containing aromatic heterocyclic complex collector according to claim 6, characterized in that the tungsten-containing mineral comprises at least one of wolframite, scheelite, and tungsten smelter. 8. The use of a metal ion-nitrogen-containing aromatic heterocyclic complex collector according to claim 6 or 7 is characterized in that: the tungsten-containing mineral is subjected to grinding, iron removal and desulfurization pretreatment to obtain a desulfurized tailings slurry, and after the desulfurized tailings slurry is slurried, a flotation agent containing a metal ion-nitrogen-containing aromatic heterocyclic complex collector and a salinized water glass inhibitor is used to float the tungsten ore to obtain a tungsten concentrate. 9. The use of a metal ion-nitrogen-containing aromatic heterocyclic complex collector according to claim 8, characterized in that the concentration of the desulfurized tailings slurry is adjusted to 40-50wt.%, and the pH is adjusted to 9.0-10.0. 10. The use of a metal ion-nitrogen-containing aromatic heterocyclic complex collector according to claim 8, characterized in that: The tungsten ore flotation includes one roughing selection, two or more cleaning selections and two or more scavenging selections; The reagent system for the rough selection is as follows: the amount of the metal ion-nitrogen-containing aromatic heterocyclic complex collector is 300-600 g/t, and the amount of the 2# oil foaming agent is 30-50 g/t; The selected reagent system is as follows: the dosage of the salt water glass inhibitor is 50-500 g/t, and follows the principle of halving; The salted water glass is composed of aluminum sulfate and water glass in a mass ratio of aluminum sulfate to water glass of 1:(2-4); The reagent system for the sweeping is: the dosage of 2# oil foaming agent is 0~20g/t; The mass of the metal ion-nitrogen-containing aromatic heterocyclic complex collector is measured according to the mass of its nitrogen-containing aromatic heterocyclic complex.