A flotation collector for non-ferrous metal sulfide ores, its preparation method and application

Abstract

This invention belongs to the field of mineral flotation technology, and discloses a flotation collector for non-ferrous metal sulfide ores, its preparation method, and its application. The collector uses O,O-dialkyldithiophosphate as a starting material, and reacts sequentially with a halocarboxylic acid ester, hydrazine hydrate, potassium hydroxide, and carbon disulfide in anhydrous ethanol in a three-step reaction to obtain the target product, O,O-dialkyldithiophosphate hydrazide-N′-dithiocarbamate potassium. Its molecular structure simultaneously contains three active groups: a dithiophosphate group, an hydrazide group, and a dithiocarbamate group. This invention achieves efficient process connection and smooth transition by optimizing the material ratio, temperature, and time of each reaction step, and has advantages such as mild reaction conditions, simple operation, few side reactions, high yield, and stable product. The prepared collector exhibits excellent collecting performance and good selectivity for non-ferrous metal sulfide ores such as chalcopyrite, and is suitable for widespread application in sulfide ore flotation processes.

Description

Technical Field

[0001] This invention relates to the field of mineral flotation technology, and in particular to a flotation collector for non-ferrous metal sulfide ores, its preparation method, and its application. Background Technology

[0002] Copper is an important metal in economic production, possessing good ductility and electrical conductivity, and readily alloying with various elements. Therefore, it is widely used in electrical, electronics, defense, construction, machinery, and light industry sectors. The main source of copper is copper sulfide ore; however, with the massive consumption of copper due to economic and social development, the reserves of easily beneficiated copper sulfide ore in industry are rapidly decreasing. Therefore, improving the development and utilization efficiency of low-grade and difficult-to-benefit copper sulfide ores is key to solving the copper resource shortage problem.

[0003] Flotation is the main method for beneficiating copper sulfide ores. Its basic principle is to separate minerals from gangue by utilizing the selective adsorption of collectors on the mineral surface. The performance of the collector directly affects the flotation effect, especially the balance between selectivity and collecting power. Currently, the most widely used sulfide ore collectors in industry are xanthates (xanthates), dithiophosphates (dithiophosphates), and thiourates. While these traditional collectors each have their advantages, they also have significant drawbacks: xanthates have strong collecting power but poor selectivity, easily causing mis-collection of associated sulfide ores; dithiophosphates have improved selectivity but reduced collecting power, and generally suffer from strong odor and poor dispersibility in the pulp.

[0004] To overcome the limitations of the aforementioned collectors, researchers have recently focused on developing novel collectors with novel structures and superior performance. Integrating multiple active groups into the same molecular structure to construct multifunctional collectors is considered an effective way to improve collecting performance and selectivity. For example, multifunctional compounds containing dithiophosphate, hydrazide, and dithiocarbamate units can theoretically achieve stronger adsorption capacity and better selectivity through multiple coordination interactions with metal ions on mineral surfaces. However, the synthesis of such complex collectors often faces problems such as cumbersome steps, difficult process control, low yield, and numerous side reactions, limiting their practical application.

[0005] Therefore, how to optimize reaction steps and rationally control process conditions while ensuring the structural integrity of the target product, so as to achieve efficient connection between each reaction stage, simplify the operation process, improve the overall conversion rate and enhance process controllability, and develop sulfide mineral collectors and their preparation methods that have both excellent flotation performance and good industrial applicability, has become an important problem that urgently needs to be solved in this technical field. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a flotation collector for non-ferrous metal sulfide ores, its preparation method, and its application. The aim is to obtain a novel collector with high collecting performance, good selectivity, and industrial applicability through an optimized synthesis process.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] A flotation collector for non-ferrous metal sulfide ores, wherein the collector is potassium O,O-dialkyldithiophosphorylhydrazide-N′-dithiocarbamate, having the following structural formula:

[0009] ;

[0010] Among them, R 1 R 2 Each alkyl group is independently selected from C1 to C8; R 3 It is a C1~C4 alkylene group.

[0011] A method for preparing a flotation collector for non-ferrous metal sulfide ores includes the following steps:

[0012] Step 1: In anhydrous ethanol, the O,O-dialkyl dithiophosphate of formula (I) is reacted with the halocarboxylic acid ester of formula (II) to obtain the intermediate O,O-dialkyl dithiophosphate thioester of formula (III).

[0013] Step 2: The intermediate O,O-dialkyldithiophosphate thioester is reacted with hydrazine hydrate of formula (IV) to obtain the intermediate O,O-dialkyldithiophosphate thiohydrazine of formula (V).

[0014] Step 3: The intermediate O,O-dialkyldithiophosphate thiohydrazide is reacted with potassium hydroxide and carbon disulfide to obtain O,O-dialkyldithiophosphate hydrazide-N′-dithioformate potassium with the structure of formula (VI).

[0015] The reaction formula is as follows:

[0016] ;

[0017] Among them, R 1 R 2 Each alkyl group is independently selected from C1 to C8; R 3 It is a C1~C4 alkylene group; R 4 It is a C1~C8 alkyl group; M is Na + K + or NH4 + Y is Cl, Br, or I.

[0018] In the above scheme, the molar ratio of O,O-dialkyl dithiophosphate: halocarboxylic acid ester: hydrazine hydrate: potassium hydroxide: carbon disulfide is 1:1~1.2:1~1.5:1~1.4:1~1.4.

[0019] In the above scheme, in step 1, the volume of anhydrous ethanol used for 1 mol of O,O-dialkyl dithiophosphate is 50~200 mL.

[0020] In the above scheme, the specific method of step 1 is as follows: O,O-dialkyl dithiophosphate is mixed with anhydrous ethanol, heated to 40~60℃, and then halocarboxylic acid ester is slowly added dropwise. After the addition is completed, the reaction continues for 3~5 hours. After cooling to room temperature, the generated salt is removed by suction filtration, and the intermediate O,O-dialkyl dithiophosphate thioester is obtained by rotary evaporation under reduced pressure.

[0021] In the above scheme, the specific method of step 2 is as follows: the intermediate O,O-dialkyldithiophosphate thioester is mixed with anhydrous ethanol, heated to 50~70℃, and hydrazine hydrate is slowly added dropwise. After the addition is completed, the reaction continues for 5~7h, and the intermediate O,O-dialkyldithiophosphate thiohydrazide is obtained by rotary evaporation under reduced pressure.

[0022] In the above scheme, the specific method of step 3 is as follows: the intermediate O,O-dialkyldithiophosphate thiohydrazide is mixed with anhydrous ethanol containing potassium hydroxide, carbon disulfide is slowly added dropwise, and the reaction is continued at 20~30℃ for 8~10h. Ethyl acetate is added to the system, and after extraction, washing with water, filtration and rotary evaporation, the target product O,O-dialkyldithiophosphate hydrazide-N′-dithioformate potassium is obtained.

[0023] Application of a flotation collector for non-ferrous metal sulfide ores as described above in the flotation of non-ferrous metal sulfide ores.

[0024] In a further technical solution, the non-ferrous metal sulfide ore includes one or more of chalcopyrite, pyrite, galena, sphalerite, and pyrrhotite.

[0025] Through the above technical solution, the flotation collector for non-ferrous metal sulfide ores provided by the present invention, its preparation method, and its application have the following beneficial effects:

[0026] (i) The collector has a novel structure and superior performance.

[0027] 1. Synergistic Effect of Multiple Active Sites: The collector molecule of this invention simultaneously contains three functional groups: dithiophosphate group, hydrazide group, and dithiocarbamate group, forming multiple coordination and adsorption sites. This unique structure enables it to undergo stronger chelation and chemisorption with metal ions on the surface of non-ferrous metal sulfide ores, significantly improving the collecting capacity and selectivity, especially showing a high recovery rate of nearly 98% in chalcopyrite flotation;

[0028] 2. Improved environmental friendliness: Compared with traditional dithiophosphate collectors, the collector of the present invention has better dispersibility in slurry and significantly reduced irritating odor, thus improving the flotation operation environment.

[0029] (ii) The preparation process is efficient and controllable, and suitable for industrialization.

[0030] 1. Simple and smooth process route: This invention efficiently constructs the target molecule through a three-step reaction. The steps are closely connected, and intermediates do not require complex separation and purification, which greatly simplifies the operation process, shortens the production cycle, and reduces energy consumption and production costs.

[0031] 2. Mild and controllable reaction conditions: Each step of the reaction is carried out under moderate temperature (20-70℃) and normal pressure conditions, without the need for demanding equipment, safe operation, good reproducibility, and conducive to stable industrial production;

[0032] 3. High product yield and high purity: By precisely controlling the material molar ratio, reaction temperature and time of each reaction step, side reactions are effectively suppressed, so that the yield of the target product is stable at over 85%, and the structure is clear and the performance is stable.

[0033] (III) Good application effect of flotation

[0034] 1. Strong collecting ability: This collector has a good collecting effect on chalcopyrite and is suitable for flotation recovery of chalcopyrite;

[0035] 2. Mild flotation conditions: Highly efficient flotation can be achieved under conventional reagent regimes without special adjustments, making it easy to integrate into existing flotation processes.

[0036] (iv) Outstanding overall technical and economic efficiency

[0037] This invention successfully synthesized a novel collector with a novel structure and excellent performance. The optimized preparation process solves the problems of cumbersome synthesis steps, low yield, and difficulty in industrialization associated with this type of multifunctional compound. The overall technical solution improves flotation performance while considering production feasibility, economic efficiency, and environmental friendliness, providing a new technological option for the efficient development of difficult-to-process, low-grade sulfide mineral resources. Detailed Implementation

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below.

[0039] This invention provides a flotation collector for non-ferrous metal sulfide ores, its preparation method, and its application. Specific embodiments are as follows:

[0040] Example 1

[0041] The preparation of potassium O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate includes the following steps:

[0042] Step 1: Dissolve 0.50 mol of O,O-dibutyldithiophosphate ammonium in 100 mL of anhydrous ethanol, heat to 50 °C, and slowly add 0.50 mol of methyl chloroacetate dropwise under stirring. After the addition is complete, continue the reaction for 3 h. After the reaction is complete, cool to room temperature, filter to remove the generated ammonium chloride, and evaporate the filtrate under reduced pressure to obtain the intermediate O,O-dibutyldithiophosphate methyl thioacetate.

[0043] Step 2: Dissolve the intermediate O,O-dibutyldithiophosphate methyl thioacetate in 80 mL of anhydrous ethanol, heat to 65 °C, and slowly add 0.75 mol of hydrazine hydrate dropwise. After the addition is complete, continue the reaction for 6 h. After the reaction is complete, rotary evaporate under reduced pressure to obtain the intermediate O,O-dibutyldithiophosphate methyl thioacetyl hydrazine.

[0044] Step 3: The intermediate O,O-dibutyldithiophosphate acetylhydrazine thioacetate was dissolved in 100 mL of anhydrous ethanol containing 0.6 mol potassium hydroxide. 0.6 mol carbon disulfide was slowly added dropwise at 25 °C, and the reaction continued for 10 h after the addition was complete. Ethyl acetate was added to the system, and after extraction, washing with water, filtration, and rotary evaporation, the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was obtained with a yield of 87.6%.

[0045] The reaction formula is as follows:

[0046] .

[0047] Example 2

[0048] The method for preparing O,O-diisobutyl dithiophosphate acetylhydrazine-N′-dithiocarboxylate potassium was the same as in Example 1, except that O,O-dibutyl dithiophosphate ammonium in Example 1 was replaced with O,O-diisobutyl dithiophosphate potassium, and the target product O,O-diisobutyl dithiophosphate acetylhydrazine-N′-dithiocarboxylate potassium was obtained with a yield of 86.9%.

[0049] The reaction formula is as follows:

[0050] .

[0051] Example 3

[0052] The method for preparing potassium O,O-diisopropyl dithiophosphate acetylhydrazine-N′-dithiocarbamate is the same as in Example 1, except that the O,O-dibutyl dithiophosphate ammonium in Example 1 is replaced with O,O-diisopropyl dithiophosphate ammonium, and the target product O,O-diisopropyl dithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is obtained with a yield of 87.3%.

[0053] The reaction formula is as follows:

[0054] .

[0055] Example 4

[0056] The method for preparing potassium O,O-diethyldithiophosphate acetylhydrazine-N′-dithiocarbamate is the same as in Example 1, except that the O,O-dibutyldithiophosphate ammonium in Example 1 is replaced with O,O-diethyldithiophosphate ammonium, and the target product O,O-diethyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is obtained with a yield of 86.7%.

[0057] The reaction formula is as follows:

[0058] .

[0059] Example 5

[0060] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was the same as in Example 1, except that methyl chloroacetate in Example 1 was replaced with ethyl chloroacetate, and the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was obtained with a yield of 86.9%.

[0061] The reaction formula is as follows:

[0062] .

[0063] Example 6

[0064] The method for preparing O,O-dibutyldithiophosphate butyrylhydrazide-N′-dithiocarbamate potassium is the same as in Example 1, except that methyl chloroacetate in Example 1 is replaced with methyl chlorobutyrate to obtain the target product O,O-dibutyldithiophosphate butyrylhydrazide-N′-dithiocarbamate potassium, with a yield of 87.7%.

[0065] The reaction formula is as follows:

[0066] .

[0067] Example 7

[0068] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was the same as in Example 1, except that the 0.50 mol methyl chloroacetate in Example 1 was replaced with 0.55 mol methyl chloroacetate, and the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was obtained with a yield of 87.9%.

[0069] Example 8

[0070] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was the same as in Example 1, except that the 0.75 mol of hydrazine hydrate in Example 1 was replaced with 0.60 mol of hydrazine hydrate to obtain the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium, with a yield of 85.3%.

[0071] Example 9

[0072] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was the same as in Example 1, except that the 0.60 mol potassium hydroxide and 0.60 mol carbon disulfide in Example 1 were replaced with 0.70 mol potassium hydroxide and 0.70 mol carbon disulfide, to obtain the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium, with a yield of 87.8%.

[0073] Example 10

[0074] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is the same as in Example 1, except that the 50℃ in step 1 of Example 1 is changed to 60℃, and the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is obtained with a yield of 85.1%.

[0075] Example 11

[0076] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is the same as in Example 1, except that the temperature in step 2 of Example 1 is changed from 65℃ to 70℃, and the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is obtained with a yield of 85.9%.

[0077] Example 12

[0078] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is the same as in Example 1, except that the temperature in step 3 of Example 1 is changed from 25°C to 30°C, and the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is obtained with a yield of 86.6%.

[0079] Example 13

[0080] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is the same as in Example 1, except that the 3h in step 1 of Example 1 is changed to 4h, and the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is obtained with a yield of 87.7%.

[0081] Example 14

[0082] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was the same as in Example 1, except that the 6h in step 2 of Example 1 was changed to 5h, and the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was obtained with a yield of 86.7%.

[0083] Example 15

[0084] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is the same as in Example 1, except that the 10h in step 3 of Example 1 is changed to 8h, and the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium is obtained with a yield of 86.4%.

[0085] Example 16

[0086] Chalcopyrite was floated using the O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium flotation method prepared in Example 1: the O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium flotation method was 5 mg / L, the amount of frother (MIBC) was 10 mg / L, the rotation speed was 1758 r / min, and chalcopyrite with a particle size of -76 μm to +38 μm was floated for 3 minutes. When the pulp pH was 9.0, the recovery rate of chalcopyrite was 97.53%.

[0087] Example 17

[0088] Chalcopyrite was floated using the O,O-diisobutyl dithiophosphate acetylhydrazine-N′-dithiocarbamate potassium flotation method prepared in Example 2: the O,O-diisobutyl dithiophosphate acetylhydrazine-N′-dithiocarbamate potassium flotation method was 5 mg / L, the amount of frother (MIBC) was 10 mg / L, the rotation speed was 1758 r / min, and chalcopyrite with a particle size of -76 μm to +38 μm was floated for 3 minutes. When the pulp pH was 9.0, the recovery rate of chalcopyrite was 97.47%.

[0089] Example 18

[0090] Chalcopyrite was floated using the O,O-dibutyldithiophosphate butyrylhydrazide-N′-dithiocarbamate potassium flotation method prepared in Example 6: the O,O-dibutyldithiophosphate butyrylhydrazide-N′-dithiocarbamate potassium flotation method was 5 mg / L, the amount of frother (MIBC) was 10 mg / L, the rotation speed was 1758 r / min, and chalcopyrite with a particle size of -76 μm to +38 μm was floated for 3 minutes. When the pulp pH was 9.0, the recovery rate of chalcopyrite was 96.48%.

[0091] Comparative Example 1

[0092] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium used in Example 1 was changed from 50°C to 30°C to obtain the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium with a yield of 65.4%.

[0093] Comparative Example 2

[0094] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium used in Example 1 was changed from 65°C to 30°C to obtain the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium with a yield of 57.9%.

[0095] Comparative Example 3

[0096] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium used in Example 1 was changed from 25°C to 5°C to obtain the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium with a yield of 34.2%.

[0097] Comparative Example 4

[0098] The method for preparing potassium O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate used in Example 1 was modified by changing 0.50 mol of methyl chloroacetate to 0.45 mol of methyl chloroacetate, and the target product, potassium O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate, was obtained with a yield of 77.8%.

[0099] Comparative Example 5

[0100] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium used in Example 1 was modified by changing 0.75 mol of hydrazine hydrate to 0.45 mol of hydrazine hydrate, and the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium was obtained with a yield of 62.7%.

[0101] Comparative Example 6

[0102] The method for preparing potassium O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate used in Example 1 was modified by changing the ingredients from 0.60 mol potassium hydroxide and 0.60 mol carbon disulfide to 0.45 mol potassium hydroxide and 0.45 mol carbon disulfide, yielding the target product potassium O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate with a yield of 73.2%.

[0103] Comparative Example 7

[0104] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium used in Example 1 was changed from 3h to 1.5h to obtain the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium with a yield of 46.7%.

[0105] Comparative Example 8

[0106] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium used in Example 1 was changed from 6h to 3h to obtain the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium with a yield of 68.7%.

[0107] Comparative Example 9

[0108] The method for preparing O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium used in Example 1 was changed from 10h to 5h to obtain the target product O,O-dibutyldithiophosphate acetylhydrazine-N′-dithiocarbamate potassium with a yield of 60.5%.

[0109] As can be seen from the above comparative examples, when the material ratio, reaction temperature, or reaction time in the reaction step exceeds the limits defined by this invention, the yield of the target product decreases significantly. This indicates that the limitations on each reaction parameter in this invention are not arbitrary selections, but rather key technical features for achieving high yield and process stability.

[0110] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A flotation collector for non-ferrous metal sulfide ores, characterized in that, The collector is potassium O,O-dialkyldithiophosphatidylhydrazide-N′-dithiocarbamate, which has the following structural formula: ； Among them, R 1 R 2 Each alkyl group is independently selected from C1 to C8; R 3 It is a C1~C4 alkylene group.

2. A method for preparing a flotation collector for non-ferrous metal sulfide ores as described in claim 1, characterized in that, Includes the following steps: Step 1: In anhydrous ethanol, the O,O-dialkyl dithiophosphate of formula (I) is reacted with the halocarboxylic acid ester of formula (II) to obtain the intermediate O,O-dialkyl dithiophosphate thioester of formula (III). Step 2: The intermediate O,O-dialkyldithiophosphate thioester is reacted with hydrazine hydrate of formula (IV) to obtain the intermediate O,O-dialkyldithiophosphate thiohydrazine of formula (V). Step 3: The intermediate O,O-dialkyldithiophosphate thiohydrazide is reacted with potassium hydroxide and carbon disulfide to obtain O,O-dialkyldithiophosphate hydrazide-N′-dithioformate potassium with the structure of formula (VI). The reaction formula is as follows: ； Among them, R 1 R 2 Each alkyl group is independently selected from C1 to C8; R 3 It is a C1~C4 alkylene group; R 4 It is a C1~C8 alkyl group; M is Na + K + or NH4 + Y is Cl, Br, or I.

3. The preparation method according to claim 2, characterized in that, The molar ratio of O,O-dialkyl dithiophosphate: halocarboxylic acid ester: hydrazine hydrate: potassium hydroxide: carbon disulfide is 1:1~1.2:1~1.5:1~1.4:1~1.

4.

4. The preparation method according to claim 2, characterized in that, In step 1, the volume of anhydrous ethanol used for 1 mol of O,O-dialkyl dithiophosphate is 50~200 mL.

5. The preparation method according to claim 2, characterized in that, The specific method of step 1 is as follows: O,O-dialkyl dithiophosphate is mixed with anhydrous ethanol, heated to 40~60℃, and then halocarboxylic acid ester is slowly added dropwise. After the addition is complete, the reaction continues for 3~5 hours. After cooling to room temperature, the generated salt is removed by suction filtration, and the intermediate O,O-dialkyl dithiophosphate thioester is obtained by rotary evaporation under reduced pressure.

6. The preparation method according to claim 2, characterized in that, The specific method for step 2 is as follows: Mix the intermediate O,O-dialkyldithiophosphate thioester with anhydrous ethanol, heat to 50~70℃, slowly add hydrazine hydrate dropwise, continue the reaction for 5~7h after the addition is complete, and obtain the intermediate O,O-dialkyldithiophosphate thiohydrazide by rotary evaporation under reduced pressure.

7. The preparation method according to claim 2, characterized in that, The specific method for step 3 is as follows: The intermediate O,O-dialkyldithiophosphate thiohydrazide is mixed with anhydrous ethanol containing potassium hydroxide, carbon disulfide is slowly added dropwise, and the reaction is continued at 20~30℃ for 8~10h. Then, ethyl acetate is added to the system, and after extraction, washing with water, filtration and rotary evaporation, the target product O,O-dialkyldithiophosphate hydrazide-N′-dithioformate potassium is obtained.

8. The application of the flotation collector for non-ferrous metal sulfide ores as described in claim 1 in the flotation of non-ferrous metal sulfide ores.

9. The application according to claim 8, characterized in that, The non-ferrous metal sulfide ores include one or more of chalcopyrite, pyrite, galena, sphalerite, and pyrrhotite.

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