A method for preparing a polythiocarboxylic acid amine copper-molybdenum separation inhibitor

Abstract

The invention relates to the technical field of copper-molybdenum separation inhibitors, and discloses a method for preparing a polythiocarboxylic acid amine copper-molybdenum separation inhibitor. The invention separates and purifies the tail liquid generated by preparing thiocarbamate to obtain sodium thioglycolate, and then reacts with carbon disulfide using potassium hydroxide as a catalyst to obtain a novel polythiocarboxylic acid amine copper-molybdenum separation inhibitor. The resource utilization of the thiocarbamate tail liquid is achieved, the raw materials are cheap and easy to obtain, and the process is green and environmentally friendly. The polythiocarboxylic acid amine copper-molybdenum separation inhibitor has the advantages of good adaptability, safety and environmental protection, good inhibition effect, simple process, and a wide range of production raw materials.

Description

Technical Field

[0001] The invention relates to the technical field of copper-molybdenum separation inhibitors, and specifically to a method for preparing a polythiocarboxylic acid amine copper-molybdenum separation inhibitor. Background Art

[0002] Copper and molybdenum are both important mineral resources, playing an important role in industrial production and national economic development. Copper-molybdenum separation is the main technical difficulty in developing copper-molybdenum ore. Therefore, it is of great significance to develop high-performance copper-molybdenum separation inhibitors. Compared with traditional inorganic separation inhibitors, organic separation inhibitors such as thiocarbamates, thioglycolic acid, etc., have the advantages of low toxicity, low pollution and low dosage. The invention patent with announcement number CN109482357B discloses the preparation and application of copper-molybdenum separation inhibitors, and the copper-molybdenum separation inhibitor obtained by reacting thioglycolic acid and ethanolamine is N-(2-hydroxyethyl)-2-mercaptoacetamide, which can be applied to the flotation separation of molybdenite and copper sulfide minerals in copper-molybdenum mixed concentrate. Compared with the copper-molybdenum separation inhibitor of the invention, the present invention uses thiocarbamate tail liquid, carbon disulfide, etc. as raw materials to prepare polythiocarboxylic acid amine copper-molybdenum separation inhibitors, which have the advantages of green environmental protection, simple process, and good separation inhibition efficiency. Summary of the invention

[0003] The technical problem solved by the present invention is to provide a novel polythiocarboxylic acid amine copper-molybdenum separation inhibitor, which realizes the specific inhibition of copper minerals and the efficient flotation separation of copper and molybdenum.

[0004] The technical scheme of the present invention is: a method for preparing a polythiocarboxylic acid amine copper-molybdenum separation inhibitor: adding ammonium thioglycolate into a flask, heating to a reaction temperature, then adding potassium hydroxide, and dripping carbon disulfide to react to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0005] The molar ratio of ammonium thioglycolate, potassium hydroxide and carbon disulfide is 1:(1-1.1):(1-1.5).

[0006] Preferably, the reaction temperature is 15-55°C, and the reaction time is 30-90 min.

[0007] Preferably, the preparation method of ammonium thioglycolate is:

[0008] (1) Add the tail liquid produced during the preparation of thiocarbamate into xylene, shake it and let it stand to separate the layers, and collect the sodium thioglycolate solution in the lower layer.

[0009] (2) The sodium thioglycolate solution is subjected to reduced pressure distillation, the pressure is controlled to be -0.06 to -0.1 MPa, and the temperature is 55-65°C; the material is then cooled at -10°C to -5°C, filtered, and the filtrate is collected.

[0010] (3) adding a sulfurous acid mixed solution consisting of sulfurous acid and hydrochloric acid solution to the filtrate while stirring, and adjusting the pH value of the filtrate to 3-3.3; adding an ammonia solution having a mass concentration of 15-28% to adjust the pH value of the filtrate to 7.2-7.8; introducing ammonia gas to adjust the pH value of the filtrate to 8.2-8.8, heating to 35-45° C., stirring for 40-60 min, filtering after cooling, and vacuum drying the filtrate to remove impurities to obtain ammonium thioglycolate.

[0011] The technical effect of the present invention is that the tail liquid generated by preparing thiocarbamate is separated and purified to obtain sodium thioglycolate, and then potassium hydroxide is used as a catalyst to react with carbon disulfide to obtain a novel polythiocarboxylic acid amine copper-molybdenum separation inhibitor. The resource utilization of the thiocarbamate tail liquid is achieved, the raw materials are cheap and easy to obtain, and the process is green and environmentally friendly.

[0012] The polythiocarboxylic acid amine copper-molybdenum separation inhibitor prepared by the present invention has the advantage of good adaptability. In practical applications, the agent has shown excellent performance in the industrial test process of porphyry copper-molybdenum mines and skarn copper-molybdenum mines in Heilongjiang, Jilin, Luoyang, Shaanxi and other places. It not only has a good inhibitory effect on primary copper minerals (chalcopyrite), reaching the technical requirement of copper content below 0.5%, but also does not affect the recovery of molybdenum minerals, effectively ensuring the comprehensive economic benefits. At the same time, in some mines containing secondary copper ores (chalcocite, azurite, etc.), it can stably inhibit primary copper ores and have a certain auxiliary inhibitory effect on secondary copper ores. In addition, in industrial tests in northern regions, it can efficiently inhibit copper minerals during high temperature periods in summer, realize rapid and stable separation of copper and molybdenum, and the dosage is one-fifth to one-thirtieth of conventional copper inhibitors, so that copper-molybdenum minerals can be efficiently recovered and comprehensively utilized.

[0013] The polythiocarboxylic acid amine copper-molybdenum separation inhibitor of the present invention is safe and environmentally friendly. The toxicity is much lower than that of sodium cyanide, sodium sulfide and sodium hydrosulfide, and it is not a hazardous chemical, and no special protection is required during production, transportation and use. There is no special irritating odor and the safety factor is high. It is friendly to water bodies and does not require separate backwater treatment. It can meet the reuse standard through natural sedimentation and decomposition in the tailings pond.

[0014] The dosage of the polythiocarboxylic acid amine copper-molybdenum separation inhibitor of the present invention is much lower than that of conventional agents such as sodium sulfide and sodium hydrosulfide, even compared with sodium cyanide, which has the best inhibitory effect among conventional inhibitors. Especially in the case of high temperature in summer, the dosage is greatly reduced, which can save a lot of costs for mining customers.

[0015] The process of the present invention is simple, the raw materials are widely available, and waste or by-products of other products can be used, thus extending the industrial chain and reducing the generation of waste. At the same time, the production process does not involve dangerous processes such as high temperature and high pressure, and no pollutants such as harmful gases, waste water, and waste residue are generated. The reaction process is stable and does not require special control. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is an open circuit test process flow chart for separation of copper and molybdenum from molybdenum ore.

[0017] Figure 2 It is a closed-loop test process flow chart for separation of copper and molybdenum from molybdenum ore. DETAILED DESCRIPTION

[0018] In order to make the technical solution of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below. It should be noted that the following embodiments are only used to better understand the technical solution of the present invention and should not be understood as limiting the present invention.

[0019] Example 1

[0020] (1) Add the tail liquid produced during the preparation of thiocarbamate into xylene, shake it and let it stand to separate the layers, and collect the sodium thioglycolate solution in the lower layer.

[0021] (2) The sodium thioglycolate solution was subjected to reduced pressure distillation, and the pressure was controlled to be -0.06 MPa and the temperature to be 60°C; the material was then cooled at -10°C, filtered and the filtrate was collected.

[0022] (3) Add a sulfurous acid mixed solution consisting of sulfurous acid and hydrochloric acid solution dropwise to the filtrate while stirring, and adjust the pH value of the filtrate to 3; after stirring, add a 28% ammonia aqueous solution dropwise to adjust the pH value of the filtrate to 7.5; after stirring, introduce ammonia gas to adjust the pH value of the filtrate to 8.5, heat to 40°C, stir for 40 minutes, cool and filter, and vacuum dry the filtrate to remove impurities to obtain ammonium thioglycolate.

[0023] (4) Add 0.1 mol of ammonium thioglycolate to the flask, control the reaction temperature to 35°C, then add 0.1 mol of potassium hydroxide, and dropwise add 0.1 mol of carbon disulfide. Stir the reaction for 45 minutes to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0024] Example 2

[0025] (1) Add the tail liquid produced during the preparation of thiocarbamate into xylene, shake it and let it stand to separate the layers, and collect the sodium thioglycolate solution in the lower layer.

[0026] (2) The sodium thioglycolate solution was subjected to reduced pressure distillation, the pressure was controlled to -0.1 MPa, and the temperature was 65°C; the material was then cooled at -10°C, filtered, and the filtrate was collected.

[0027] (3) Add a sulfurous acid mixed solution consisting of sulfurous acid and hydrochloric acid solution dropwise to the filtrate while stirring, and adjust the pH value of the filtrate to 3.3; after stirring, add a 15% ammonia aqueous solution dropwise to adjust the pH value of the filtrate to 7.8; after stirring, introduce ammonia gas to adjust the pH value of the filtrate to 8.2, heat to 35°C, stir for 60 minutes, cool and filter, and vacuum dry the filtrate to remove impurities to obtain ammonium thioglycolate.

[0028] (4) Add 0.1 mol of ammonium thioglycolate to the flask, control the reaction temperature to 35°C, then add 0.105 mol of potassium hydroxide, and dropwise add 0.1 mol of carbon disulfide. Stir the reaction for 45 minutes to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0029] Example 3

[0030] (1) Add the tail liquid produced during the preparation of thiocarbamate into xylene, shake it and let it stand to separate the layers, and collect the sodium thioglycolate solution in the lower layer.

[0031] (2) The sodium thioglycolate solution was subjected to reduced pressure distillation, and the pressure was controlled to be -0.06 MPa and the temperature to be 55°C; the material was then cooled at -5°C, filtered and the filtrate was collected.

[0032] (3) Add a sulfurous acid mixed solution consisting of sulfurous acid and hydrochloric acid solution to the filtrate while stirring, and adjust the pH value of the filtrate to 3; after stirring, add a 15-28% ammonia aqueous solution to adjust the pH value of the filtrate to 7.2; after stirring, introduce ammonia gas to adjust the pH value of the filtrate to 8.8, heat to 45° C., stir for 40 minutes, cool and filter, and vacuum dry the filtrate to remove impurities to obtain ammonium thioglycolate.

[0033] (4) Add 0.1 mol of ammonium thioglycolate to the flask, control the reaction temperature to 35°C, then add 0.11 mol of potassium hydroxide, and dropwise add 0.1 mol of carbon disulfide. Stir the reaction for 45 minutes to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0034] Example 4

[0035] (1) Add 0.1 mol of ammonium thioglycolate (prepared according to the method of Example 1) into a flask, control the reaction temperature to 35° C., then add 0.105 mol of potassium hydroxide, and dropwise add 0.105 mol of carbon disulfide, stir and react for 45 minutes to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0036] Example 5

[0037] (1) Add 0.1 mol of ammonium thioglycolate (prepared according to the method of Example 1) into a flask, control the reaction temperature to 35° C., then add 0.105 mol of potassium hydroxide, and dropwise add 0.15 mol of carbon disulfide, stir and react for 45 minutes to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0038] Table 1

[0039]

[0040] Example 6

[0041] (1) Add 0.1 mol of ammonium thioglycolate (prepared according to the method of Example 1) into a flask, control the reaction temperature to 15°C, then add 0.105 mol of potassium hydroxide, and dropwise add 0.15 mol of carbon disulfide, stir and react for 45 minutes to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0042] Example 7

[0043] (1) Add 0.1 mol of ammonium thioglycolate (prepared according to the method of Example 1) into a flask, control the reaction temperature to 55° C., then add 0.105 mol of potassium hydroxide, and dropwise add 0.15 mol of carbon disulfide. Stir the reaction for 45 minutes to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0044] Table 2

[0045]

[0046] Example 8

[0047] (1) Add 0.1 mol of ammonium thioglycolate (prepared according to the method of Example 1) into a flask, control the reaction temperature to 15°C, then add 0.105 mol of potassium hydroxide, and dropwise add 0.15 mol of carbon disulfide, stir and react for 30 minutes to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0048] Example 9

[0049] (1) Add 0.1 mol of ammonium thioglycolate (prepared according to the method of Example 1) into a flask, control the reaction temperature to 15° C., then add 0.105 mol of potassium hydroxide, and dropwise add 0.15 mol of carbon disulfide, stir and react for 90 minutes to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor.

[0050] Table 3

[0051]

[0052] From the test results in Tables 1 to 3, when the material ratio of the raw materials ammonium thioglycolate, potassium hydroxide and carbon disulfide is 1:1.05:1.5, the reaction temperature is controlled at 15°C, and the material reaction time is 90 minutes, a polythiocarboxylic acid amine copper-molybdenum separation inhibitor product with higher quality and content is obtained.

[0053] A laboratory closed-circuit test was conducted on the separation of copper and molybdenum in a copper-molybdenum mine in Heilongjiang. The open-circuit test process is that the ore is ground and then roughly selected, and the roughing foam is pre-selected and then separated and selected twice, and inhibitors are added to separate copper and molybdenum, and finally a qualified molybdenum concentrate is obtained.

[0054] The specific laboratory open circuit test process is: take 1000g copper-molybdenum ore sample for grinding, the grinding fineness is -200 mesh accounting for 65%, add 40g / t diesel, 10g / t xanthate, 60g / t foaming agent pine oil for roughing, and obtain roughing foam; then perform pre-selection, add 300g / t of polythiocarboxylic acid amine copper-molybdenum separation inhibitor (prepared by Example 9) or conventional separation inhibitor to the roughing foam, perform a separation and selection, and obtain a primary concentrate foam; then add 150g / t of polythiocarboxylic acid amine copper-molybdenum separation inhibitor or conventional copper-molybdenum separation inhibitor sodium sulfide, perform secondary separation and selection, and obtain secondary separation and selection foam, which is a qualified molybdenum concentrate. Open circuit test process flow chart see Figure 1 ; The copper content in molybdenum concentrate is tested and tested. The copper content in molybdenum concentrate is required to be less than 0.3%. The test results are shown in the table below.

[0055] Table 4

[0056]

[0057] The test results show that after flotation using the polythiocarboxylic acid amine copper-molybdenum separation inhibitor, the Mo content in the molybdenum concentrate reaches 61.0816%, and the Cu content is only 0.13%. Its inhibitory effect is better than that of the conventional copper-molybdenum separation inhibitor sodium sulfide.

[0058] In order to better reflect the inhibitory effect of the reagent, 5 groups of closed-circuit verification tests were carried out. The closed-circuit test is a cyclic test that simulates the actual production process. The specific process is: the first group of open-circuit tailings 1 are returned to the roughing of the next group of ore sample tests, and the first group of tailings 2 and tailings 3 are returned to the next group of tests. Selected 1 and selected 2, finally, molybdenum concentrate and tailings are obtained for cyclic flotation. The closed-circuit test process flow chart is shown in Figure 2 .

[0059] Table 5

[0060]

[0061] As can be seen from the above table, through the open circuit and closed circuit tests for the separation comparison of copper-molybdenum ore, it can be verified that the polythiocarboxylic acid amine copper-molybdenum separation inhibitor of the present invention has a good inhibitory effect.

[0062] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A method for preparing a polythiocarboxylic acid amine copper-molybdenum separation inhibitor, characterized in that: The preparation method comprises: adding ammonium thioglycolate into a flask, heating to a reaction temperature, then adding potassium hydroxide, and dripping carbon disulfide to react to obtain a polythiocarboxylic acid amine copper-molybdenum separation inhibitor; The molar ratio of ammonium thioglycolate, potassium hydroxide and carbon disulfide is 1:(1-1.1):(1-1.5); The reaction temperature is 15-55°C, and the reaction time is 30-90 minutes.

2. The method for preparing the polythiocarboxylic acid amine copper-molybdenum separation inhibitor according to claim 1, characterized in that: The preparation method of the ammonium thioglycolate is: (1) Add the tail liquid produced during the preparation of thiocarbamate into xylene, shake it and let it stand to separate the layers, and collect the sodium thioglycolate solution in the lower layer; (2) distilling the sodium thioglycolate solution under reduced pressure, cooling the material, filtering and collecting the filtrate; (3) Add sulfurous acid mixed solution dropwise to the filtrate while stirring; add ammonia solution dropwise after stirring; introduce ammonia gas after stirring, heat and stir, filter after cooling, and vacuum dry the filtrate to remove impurities to obtain ammonium thioglycolate.

3. The method for preparing the polythiocarboxylic acid amine copper-molybdenum separation inhibitor according to claim 2, characterized in that: In the above (2), the pressure during vacuum distillation is controlled to be -0.06 to -0.1 MPa and the temperature is 55-65°C; the temperature during cooling is -10°C to -5°C.

4. The method for preparing the polythiocarboxylic acid amine copper-molybdenum separation inhibitor according to claim 2, characterized in that: In the above (3), a sulfurous acid mixed solution is added dropwise to adjust the pH of the filtrate to 3-3.3; the sulfurous acid mixed solution consists of sulfurous acid and hydrochloric acid solution.

5. The method for preparing the polythiocarboxylic acid amine copper-molybdenum separation inhibitor according to claim 2, characterized in that: In the step (3), an aqueous ammonia solution is added dropwise to adjust the pH of the filtrate to 7.2-7.8; the mass concentration of the aqueous ammonia solution is 15-28%.

6. The method for preparing the polythiocarboxylic acid amine copper-molybdenum separation inhibitor according to claim 2, characterized in that: In the step (3), ammonia gas is introduced to adjust the pH of the filtrate to 8.2-8.

8.

7. The method for preparing the polythiocarboxylic acid amine copper-molybdenum separation inhibitor according to claim 2, characterized in that: In the above (3), the temperature during heating and stirring is 35-45°C and the time is 40-60 minutes.

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