Environment-friendly gold ore gold extraction agent and preparation method thereof

Abstract

The invention relates to the technical field of mineral separation, in particular to an environment-friendly gold ore gold extraction agent and a preparation method thereof. The gold extraction agent is prepared from the following components in parts by weight: 20 to 30 parts of thiourea-trifluoro-triazine derivative, 10 to 20 parts of urea, 8 to 12 parts of sodium cyanurate, 6 to 18 parts of carbonate, 5 to 10 parts of stabilizer and 5 to 8 parts of oxidant. The gold extraction agent provided by the invention belongs to a non-cyanide gold extraction agent, is safe and environment-friendly, is extremely high in gold extraction leaching rate, and is particularly suitable for treating low-arsenic and low-sulfur gold ores and gold ores containing other harmful elements.

Description

Technical Field

[0001] The present invention relates to the technical field of mineral processing, and in particular to an environmentally friendly gold extracting agent and a preparation method thereof. Background Art

[0002] The cyanidation method has always been a dominant method for extracting gold from gold mines. This method, which uses cyanide as a leaching solution to extract gold from ore or concentrate, boasts ease of operation, high efficiency, low cost, and wide adaptability. However, as a highly toxic substance, cyanide poses numerous safety hazards during transportation, storage, and use. Negligence can lead to serious casualties and environmental pollution. Therefore, cyanidation gold extraction not only poses a significant challenge to the country and society, but also places significant pressure on gold producers.

[0003] With growing environmental awareness, the use of highly toxic compounds like cyanide (especially sodium cyanide) is increasingly restricted. GBZ1-2010, "Hygiene Standards for Industrial Enterprise Design," clearly stipulates the permissible concentration of cyanide in surface water and the safety threshold for hydrogen cyanide gas in workplace air. The introduction of these regulations has further promoted the development of environmentally friendly alternatives such as environmentally friendly gold beneficiation agents. Furthermore, the cyanide leaching process is susceptible to impurities such as copper, iron, lead, zinc, antimony, tellurium, arsenic, and sulfur. Direct leaching often yields poor results for difficult-to-process gold ores containing fine-grained gold, high arsenic and sulfur content, and organic carbon. Complex pretreatment steps are required before cyanide leaching or enhanced leaching methods are employed, but satisfactory gold extraction results are still sometimes difficult to achieve. Furthermore, with the development and utilization of mineral resources, mineral resources are gradually decreasing, and ores with low grade, fine particle size, high concentrations of coexisting metals, and harmful impurities such as arsenic, antimony, and carbon are becoming the primary targets for gold extraction. Therefore, given the new demands for environmental protection and gold extraction processes, research on non-cyanide leaching processes and gold extraction agents is particularly important.

[0004] Environmentally friendly gold dressing agents, as an environmentally friendly alternative to sodium cyanide, are emerging in the gold leaching industry. They not only address the environmental issues associated with long-standing reliance on cyanide for gold extraction, but also offer the advantage of being unrestricted in purchase and sale. Their low toxicity, environmental friendliness, high recovery rates, operational safety, and excellent stability make the gold leaching process more efficient and convenient. Currently, commercially available environmentally friendly agents are primarily effective for treating single-component oxide ores and primary ores. However, for Carlin-type gold deposits, ores with low arsenic and low sulfur content, and other gold deposits containing harmful elements, pre-treatment is required and technical issues such as low leaching rates and high gold consumption are also present. Furthermore, there is the risk of incomplete gold extraction and residual harmful gold elements. Summary of the Invention

[0005] In view of the problems existing in the prior art, the purpose of the present invention is to provide an environmentally friendly gold extraction agent and a preparation method thereof.

[0006] The purpose of the present invention is achieved by adopting the following technical solutions:

[0007] An environmentally friendly gold extraction agent for gold ore, calculated by weight, comprises the following components:

[0008] 20-30 parts of thiourea-trifluoro-triazine derivative, 10-20 parts of urea, 8-12 parts of sodium cyanurate, 6-18 parts of carbonate, 5-10 parts of stabilizer, and 5-8 parts of oxidant.

[0009] Preferably, the thiourea-trifluoro-triazine derivative is a product prepared by condensing 2,4,6-trimercapto-S-triazine and 3-aminotrifluorotoluene as reactants.

[0010] Preferably, the carbonate is at least one of sodium carbonate, potassium carbonate and ammonium carbonate.

[0011] Preferably, the stabilizer is a mixture of sodium silicate and sodium aluminate, and the mass ratio of sodium silicate to sodium aluminate is 2-3:1.

[0012] Preferably, the oxidizing agent is calcium peroxide.

[0013] Preferably, the preparation method of the thiourea-trifluoro-triazine derivative comprises:

[0014] S1. Weigh 2,4,6-trimercapto-S-triazine and anhydrous ethanol, add L-ascorbic acid under nitrogen protection, stir until fully dissolved, then add triethylamine dropwise, raise the temperature to 55-65°C, and stir at this temperature for 20-40 minutes to obtain a mixed solution A;

[0015] S2. Weigh 3-aminobenzotrifluoride and anhydrous ethanol, mix them, dissolve them fully, and then add them dropwise to mixed solution A. Then, add the catalyst, continue heating to 70-80°C, reflux and stir to react for 3-4 hours, and cool naturally to obtain mixed solution B.

[0016] S3. Place the mixed solution B in an ice-water bath and let it stand. When no new precipitate continues to be produced, quickly filter and collect the precipitate, wash it, purify it through a column, and dry it to obtain a thiourea-trifluoro-triazine derivative.

[0017] Preferably, in S1, the mass volume ratio of 2,4,6-trimercapto-S-triazine, L-ascorbic acid, triethylamine and anhydrous ethanol is 1.77 g: (0.16-0.22) g: (0.31-0.62) g: (50-100) mL.

[0018] Preferably, in S2, the mass volume ratio of 3-aminotrifluorotoluene, anhydrous ethanol and mixed solution A is 4.83 g: (20-30) mL: (50-100) mL.

[0019] Preferably, in S2, the catalyst is copper bromide, and the amount added is 1%-5% of the mass of 3-aminobenzotrifluoride.

[0020] Preferably, in S3, washing is performed using ice ethanol (0-5° C.) at least twice.

[0021] Preferably, in S3, the column purification is performed by passing through a 200-300 mesh silica gel column and eluting with ethyl acetate / petroleum ether in a volume ratio of 1:1.

[0022] Preferably, in S3, the drying is to remove the solvent by rotary evaporation and then vacuum drying at 40° C. for 12 h.

[0023] In a second aspect, the present invention provides a method for preparing an environmentally friendly gold extraction agent, comprising the following steps:

[0024] Step 1: Weigh the thiourea-trifluoro-triazine derivative, urea, sodium cyanurate, carbonate, stabilizer and oxidant according to their weight parts and set aside;

[0025] Step 2: first add urea and sodium cyanurate into a stainless steel reactor, heat to 150-200°C, and stir at 200-300 rpm for 20-30 minutes;

[0026] Step 3, continue to add thiourea-trifluoro-triazine derivatives, carbonates and stabilizers into the reactor, heat to 320-360°C, and stir at 200-300 rpm for 3-4 hours;

[0027] Step 4: Cool the reactor to room temperature under nitrogen, take out the mixture in the reactor, grind it and pass it through a 50-mesh sieve to obtain the main material product;

[0028] Step 5: weigh the oxidant and the main ingredient product, add them into a mixer, and stir at a speed of 20-50 rpm for 10-20 minutes to obtain an environmentally friendly gold extraction agent, which is then vacuum-sealed and stored.

[0029] In a third aspect, the present invention provides an application of an environmentally friendly gold extraction agent, comprising the following steps:

[0030] (1) Mixing the prepared environmentally friendly gold extraction agent with deionized water, and adjusting the pH of the system to 11.0-12.0 using calcium hydroxide or sodium hydroxide solution to obtain a gold extraction agent mixture;

[0031] (2) crush the gold ore to be leached, pass it through a 200-mesh sieve, and use a gold extraction agent mixture for leaching. The leaching time is 12-36 hours and the leaching temperature is 15-50°C;

[0032] (3) After leaching is completed, the solid and liquid are separated, and adsorption is carried out using adsorptive materials (such as activated carbon or ion exchange resin), and then desorption electrolysis is performed to obtain gold mud for purification.

[0033] The beneficial effects of the present invention are:

[0034] 1. The gold extraction agent provided by the present invention is a non-cyanide gold extraction agent, which is not only safe and environmentally friendly, but also has a very high gold leaching rate. It is particularly suitable for treating low-arsenic and low-sulfur gold mines and gold mines containing other harmful elements.

[0035] 2. The gold extraction agent of the present invention uses thiourea-trifluoro-triazine derivatives as the main gold-dissolving raw materials, and achieves environmentally friendly gold extraction through the synergistic effect of an alkaline environment and an oxidant. The present invention is not only low-toxic and environmentally friendly, but also has a short leaching time and is extremely convenient to transport and store.

[0036] The thiourea-trifluoro-triazine derivative used in this invention is prepared by condensing 2,4,6-trimercapto-S-triazine and 3-aminobenzotrifluoride as reactants. Compared to traditional thiourea compounds, it has better selectivity and higher stability, achieving a higher leaching rate.

[0037] 4. The gold extraction agent of the present invention can be prepared in a short time, and the synthesis temperature is low, which reduces the production cost and the requirements for equipment, and fully embodies the principle of environmentally friendly production. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is described below through specific examples. It should be understood that the one or more method steps mentioned in the present invention do not exclude the presence of other method steps before and after the combination step or the insertion of other method steps between these explicitly mentioned steps; it should also be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to define the scope of the present invention. Changes or adjustments in their relative relationships, without substantially changing the technical content, should also be regarded as the scope of the present invention.

[0039] In order to better understand the above technical solutions, exemplary embodiments of the present invention are described in more detail below. Although exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0040] The present invention will be further described below with reference to the following examples.

[0041] Example 1

[0042] An environmentally friendly gold extraction agent for gold ore, calculated by weight, comprises the following components:

[0043] 25 parts of thiourea-trifluoro-triazine derivative, 15 parts of urea, 10 parts of sodium cyanurate (trisodium cyanurate), 12 parts of sodium carbonate, 6 parts of sodium silicate, 2 parts of sodium aluminate, and 7 parts of calcium peroxide.

[0044] The preparation method of thiourea-trifluoro-triazine derivatives includes:

[0045] S1. Weigh 1.77 g of 2,4,6-trimercapto-S-triazine (trithiocyanate) into a three-necked flask, add 80 mL of anhydrous ethanol, mix thoroughly, introduce nitrogen to remove air from the flask, add 0.18 g of L-ascorbic acid, stir until fully dissolved, then dropwise add 0.45 g of triethylamine, heat to 60° C., and stir while maintaining the temperature for 30 min to obtain a mixed solution A.

[0046] S2. Weigh 4.83 g of 3-aminobenzotrifluoride and 25 mL of anhydrous ethanol in a beaker, mix them, fully dissolve them, and then add them dropwise to 80 mL of mixed solution A. The addition time is controlled to 30 min. Then, copper bromide is added as a catalyst. The temperature is continued to rise to 75° C., and the mixture is refluxed with stirring for 3 h. After natural cooling, a mixed solution B is obtained.

[0047] S3. Place the mixed solution B in an ice-water bath and let it stand. After no new precipitate is produced, quickly filter and collect the precipitate, wash it with ice ethanol at least twice, purify it with a 200-mesh silica gel column, elute it with ethyl acetate / petroleum ether in a 1:1 volume ratio, remove the solvent by rotary evaporation, and dry it in vacuo at 40°C for 12 h to obtain a thiourea-trifluoro-triazine derivative.

[0048] The preparation method of the environmentally friendly gold extraction agent comprises the following steps:

[0049] Step 1: Weigh the thiourea-trifluoro-triazine derivative, urea, sodium cyanurate, carbonate, stabilizer and oxidant according to their weight parts and set aside;

[0050] Step 2: first add urea and sodium cyanurate into a stainless steel reactor, heat to 180°C, and stir at 250 rpm for 30 minutes;

[0051] Step 3: Continue adding thiourea-trifluoro-triazine derivatives, carbonates, and stabilizers into the reactor, heating to 340° C., and stirring at 250 rpm for 3 h;

[0052] Step 4: Cool the reactor to room temperature under nitrogen, take out the mixture in the reactor, grind it and pass it through a 50-mesh sieve to obtain the main material product;

[0053] Step 5: weigh the oxidant and the main ingredient product, add them into a mixer, and stir at a speed of 30 rpm for 15 minutes to obtain an environmentally friendly gold extraction agent, which is then vacuum-sealed and stored.

[0054] Example 2

[0055] An environmentally friendly gold extraction agent for gold ore, calculated by weight, comprises the following components:

[0056] 20 parts of thiourea-trifluoro-triazine derivative, 10 parts of urea, 8 parts of sodium cyanurate, 6 parts of potassium carbonate, 3.75 parts of sodium silicate, 1.25 parts of sodium aluminate, and 5 parts of calcium peroxide.

[0057] The preparation method of thiourea-trifluoro-triazine derivatives includes:

[0058] S1. Weigh 1.77 g of 2,4,6-trimercapto-S-triazine (trithiocyanate) into a three-necked flask, add 50 mL of anhydrous ethanol, mix thoroughly, introduce nitrogen to remove air from the flask, add 0.16 g of L-ascorbic acid, stir until fully dissolved, then dropwise add 0.31 g of triethylamine, heat to 55° C., and stir while maintaining the temperature for 20 min to obtain a mixed solution A.

[0059] S2. Weigh 4.83 g of 3-aminobenzotrifluoride and 20 mL of anhydrous ethanol in a beaker, mix them, fully dissolve them, and then add them dropwise to 50 mL of mixed solution A. The addition time is controlled to 20 min. Then, copper bromide is added as a catalyst. The temperature is continued to rise to 70° C., and the mixture is refluxed with stirring for 3 h. After natural cooling, a mixed solution B is obtained.

[0060] S3. Place the mixed solution B in an ice-water bath and let it stand. After no new precipitate is produced, quickly filter and collect the precipitate, wash it with ice ethanol at least twice, purify it with a 200-mesh silica gel column, elute it with ethyl acetate / petroleum ether in a 1:1 volume ratio, remove the solvent by rotary evaporation, and dry it in vacuo at 40°C for 12 h to obtain a thiourea-trifluoro-triazine derivative.

[0061] The preparation method of the environmentally friendly gold extraction agent comprises the following steps:

[0062] Step 1: Weigh the thiourea-trifluoro-triazine derivative, urea, sodium cyanurate, carbonate, stabilizer and oxidant according to their weight parts and set aside;

[0063] Step 2: first add urea and sodium cyanurate into a stainless steel reactor, heat to 150° C., and stir at 200 rpm for 20 min;

[0064] Step 3: Continue adding thiourea-trifluoro-triazine derivatives, carbonates, and stabilizers into the reactor, heating to 320° C., and stirring at 200 rpm for 3 h;

[0065] Step 4: Cool the reactor to room temperature under nitrogen, take out the mixture in the reactor, grind it and pass it through a 50-mesh sieve to obtain the main material product;

[0066] Step 5: weigh the oxidant and the main ingredient product, add them into a mixer, and stir at a speed of 20 rpm for 10 minutes to obtain an environmentally friendly gold extraction agent, which is then vacuum-sealed and stored.

[0067] Example 3

[0068] An environmentally friendly gold extraction agent for gold ore, calculated by weight, comprises the following components:

[0069] 22 parts of thiourea-trifluoro-triazine derivative, 13 parts of urea, 10 parts of sodium cyanurate, 10 parts of ammonium carbonate, 4 parts of sodium silicate, 2 parts of sodium aluminate, and 7 parts of calcium peroxide.

[0070] The preparation method of thiourea-trifluoro-triazine derivatives includes:

[0071] S1. Weigh 1.77 g of 2,4,6-trimercapto-S-triazine (trithiocyanate) into a three-necked flask, add 60 mL of anhydrous ethanol, mix thoroughly, introduce nitrogen to remove air from the flask, add 0.17 g of L-ascorbic acid, stir until fully dissolved, then dropwise add 0.38 g of triethylamine, heat to 60° C., and stir while maintaining the temperature for 30 min to obtain a mixed solution A.

[0072] S2. Weigh 4.83 g of 3-aminobenzotrifluoride and 25 mL of anhydrous ethanol in a beaker, mix them, fully dissolve them, and then add them dropwise to 60 mL of mixed solution A. The addition time is controlled to 20 min. Then, copper bromide is added as a catalyst. The temperature is continued to rise to 70° C., and the mixture is refluxed with stirring for 4 h. After natural cooling, mixed solution B is obtained.

[0073] S3. Place the mixed solution B in an ice-water bath and let it stand. After no new precipitate is produced, quickly filter and collect the precipitate, wash it with ice ethanol at least twice, purify it with a 200-mesh silica gel column, elute it with ethyl acetate / petroleum ether in a 1:1 volume ratio, remove the solvent by rotary evaporation, and dry it in vacuo at 40°C for 12 h to obtain a thiourea-trifluoro-triazine derivative.

[0074] The preparation method of the environmentally friendly gold extraction agent comprises the following steps:

[0075] Step 1: Weigh the thiourea-trifluoro-triazine derivative, urea, sodium cyanurate, carbonate, stabilizer and oxidant according to their weight parts and set aside;

[0076] Step 2: first add urea and sodium cyanurate into a stainless steel reactor, heat to 200°C, and stir at 300 rpm for 30 minutes;

[0077] Step 3: Continue adding thiourea-trifluoro-triazine derivatives, carbonates and stabilizers into the reactor, heating to 360° C., and stirring at 300 rpm for 4 h;

[0078] Step 4: Cool the reactor to room temperature under nitrogen, take out the mixture in the reactor, grind it and pass it through a 50-mesh sieve to obtain the main material product;

[0079] Step 5: weigh the oxidant and the main ingredient product, add them into a mixer, and stir at a speed of 50 rpm for 20 minutes to obtain an environmentally friendly gold extraction agent, which is then vacuum-sealed and stored.

[0080] Example 4

[0081] An environmentally friendly gold extraction agent for gold ore, calculated by weight, comprises the following components:

[0082] 30 parts of thiourea-trifluoro-triazine derivative, 20 parts of urea, 12 parts of sodium cyanurate, 18 parts of potassium carbonate, 7.5 parts of sodium silicate, 2.5 parts of sodium aluminate, and 8 parts of calcium peroxide.

[0083] The preparation method of thiourea-trifluoro-triazine derivatives includes:

[0084] S1. Weigh 1.77 g of 2,4,6-trimercapto-S-triazine (trithiocyanate) into a three-necked flask, add 100 mL of anhydrous ethanol, mix thoroughly, introduce nitrogen to remove air from the flask, add 0.22 g of L-ascorbic acid, stir until fully dissolved, then dropwise add 0.62 g of triethylamine, heat to 65° C., and stir while maintaining the temperature for 40 min to obtain a mixed solution A.

[0085] S2. Weigh 4.83 g of 3-aminobenzotrifluoride and 30 mL of anhydrous ethanol in a beaker, mix them, fully dissolve them, and then add them dropwise to 100 mL of mixed solution A. The addition time is controlled to 30 min. Then, copper bromide is added as a catalyst. The temperature is continued to rise to 80° C., and the mixture is refluxed with stirring for 3 h. After natural cooling, mixed solution B is obtained.

[0086] S3. Place the mixed solution B in an ice-water bath and let it stand. After no new precipitate is produced, quickly filter and collect the precipitate, wash it with ice ethanol at least twice, purify it with a 300-mesh silica gel column, elute it with ethyl acetate / petroleum ether in a 1:1 volume ratio, remove the solvent by rotary evaporation, and dry it in vacuo at 40°C for 12 h to obtain a thiourea-trifluoro-triazine derivative.

[0087] The preparation method of the environmentally friendly gold extraction agent comprises the following steps:

[0088] Step 1: Weigh the thiourea-trifluoro-triazine derivative, urea, sodium cyanurate, carbonate, stabilizer and oxidant according to their weight parts and set aside;

[0089] Step 2: first add urea and sodium cyanurate into a stainless steel reactor, heat to 200°C, and stir at 300 rpm for 30 minutes;

[0090] Step 3: Continue adding thiourea-trifluoro-triazine derivatives, carbonates and stabilizers into the reactor, heating to 360° C., and stirring at 300 rpm for 4 h;

[0091] Step 4: Cool the reactor to room temperature under nitrogen, take out the mixture in the reactor, grind it and pass it through a 50-mesh sieve to obtain the main material product;

[0092] Step 5: weigh the oxidant and the main ingredient product, add them into a mixer, and stir at a speed of 50 rpm for 20 minutes to obtain an environmentally friendly gold extraction agent, which is then vacuum-sealed and stored.

[0093] Comparative Example 1

[0094] An environmentally friendly gold extraction agent for gold ore, which differs from Example 1 in that the thiourea-trifluoro-triazine derivative in the ingredients is replaced by an equal amount of thiourea, and the other ingredients remain unchanged. The preparation method is also the same as that of Example 1.

[0095] Comparative Example 2

[0096] An environmentally friendly gold extraction agent for gold ore, which differs from Example 1 in that the thiourea-trifluoro-triazine derivative in the ingredients is replaced by an equal amount of 2,4,6-trimercapto-S-triazine, and the other ingredients remain unchanged. The preparation method is also the same as that of Example 1.

[0097] Experimental testing

[0098] Select low-arsenic, low-sulfur, difficult-to-leach gold ore. The composition of the ore is shown in Table 1:

[0099] Table 1 Raw material composition of gold ore

[0100]

[0101] Note: 1.w(Au) / (g / t); 2.w(Ag) / (g / t).

[0102] The gold extraction agents prepared in Examples 1-4 and Comparative Examples 1-2 were used to leaching gold from the ores, respectively. The steps of leaching gold from the ores were as follows:

[0103] (1) Mixing an environmentally friendly gold extraction agent and deionized water at a solid-liquid ratio of 1:5, and adjusting the pH of the system to 11.0 using calcium hydroxide or sodium hydroxide solution to obtain a gold extraction agent mixture;

[0104] (2) The gold ore to be leached is crushed, passed through a 200-mesh sieve, and leached using a gold extraction agent mixture. The leaching time is 24 hours and the leaching temperature is 25°C.

[0105] The leaching rates of gold ore by different gold extraction agents are tested, as shown in Table 2:

[0106] Table 2 Gold leaching rate of different gold extraction agents

[0107] Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Gold immersion rate (%) 95.61 93.25 94.79 95.83 90.13 87.29

[0108] It can be seen from Table 2 that the gold extraction agents prepared in Examples 1-4 of the present invention not only have a higher gold leaching rate, but are also non-cyanide gold extraction agents, and have the advantages of low toxicity, environmental protection, and short leaching time.

[0109] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0110] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. An environmentally friendly gold extraction agent, characterized in that: Calculated by weight, it includes the following ingredients: 20-30 parts of thiourea-trifluoro-triazine derivative, 10-20 parts of urea, 8-12 parts of sodium cyanurate, 6-18 parts of carbonate, 5-10 parts of stabilizer, 5-8 parts of oxidant; The thiourea-trifluoro-triazine derivative is a product prepared by condensing 2,4,6-trimercapto-S-triazine and 3-aminotrifluorotoluene as reactants.

2. An environmentally friendly gold extraction agent according to claim 1, characterized in that: The carbonate is at least one of sodium carbonate, potassium carbonate and ammonium carbonate.

3. An environmentally friendly gold extraction agent according to claim 1, characterized in that: The stabilizer is a mixture of sodium silicate and sodium aluminate, and the mass ratio of sodium silicate to sodium aluminate is 2-3:

1.

4. The environmentally friendly gold extraction agent according to claim 1, characterized in that: The oxidizing agent is calcium peroxide.

5. The environmentally friendly gold extraction agent according to claim 1, characterized in that: The preparation method of the thiourea-trifluoro-triazine derivative comprises: S1. Weigh 2,4,6-trimercapto-S-triazine and anhydrous ethanol, add L-ascorbic acid under nitrogen protection, stir until fully dissolved, then add triethylamine dropwise, raise the temperature to 55-65°C, and stir at this temperature for 20-40 minutes to obtain a mixed solution A; S2. Weigh 3-aminobenzotrifluoride and anhydrous ethanol, mix them, dissolve them fully, and then add them dropwise to mixed solution A. Then, add the catalyst, continue heating to 70-80°C, reflux and stir to react for 3-4 hours, and cool naturally to obtain mixed solution B. S3. Place the mixed solution B in an ice-water bath and let it stand. When no new precipitate continues to be produced, quickly filter and collect the precipitate, wash it, purify it through a column, and dry it to obtain a thiourea-trifluoro-triazine derivative.

6. An environmentally friendly gold extraction agent according to claim 5, characterized in that: In the S1, the mass volume ratio of 2,4,6-trimercapto-S-triazine, L-ascorbic acid, triethylamine and anhydrous ethanol is 1.77 g: (0.16-0.22) g: (0.31-0.62) g: (50-100) mL.

7. The environmentally friendly gold extraction agent according to claim 5, characterized in that: In the S2, the mass volume ratio of 3-aminotrifluorotoluene, anhydrous ethanol and mixed solution A is 4.83 g: (20-30) mL: (50-100) mL.

8. The environmentally friendly gold extraction agent according to claim 5, characterized in that: In the above-mentioned S2, the catalyst is copper bromide, and the amount added is 1%-5% of the mass of 3-aminobenzotrifluoride.

9. The environmentally friendly gold extraction agent according to claim 5, characterized in that: In the S3, the column purification is performed by passing through a 200-300 mesh silica gel column and eluting with ethyl acetate / petroleum ether in a volume ratio of 1:1; and the drying is performed by rotary evaporation to remove the solvent and then vacuum drying at 40° C. for 12 h.

10. A method for preparing the environmentally friendly gold extraction agent according to claim 1, characterized in that: The following steps are involved: Step 1: Weigh the thiourea-trifluoro-triazine derivative, urea, sodium cyanurate, carbonate, stabilizer and oxidant according to their weight parts and set aside; Step 2: first add urea and sodium cyanurate into a stainless steel reactor, heat to 150-200°C, and stir at 200-300 rpm for 20-30 minutes; Step 3, continue to add thiourea-trifluoro-triazine derivatives, carbonates and stabilizers into the reactor, heat to 320-360°C, and stir at 200-300 rpm for 3-4 hours; Step 4: Cool the reactor to room temperature under nitrogen, take out the mixture in the reactor, grind it and pass it through a 50-mesh sieve to obtain the main material product; Step 5: weigh the oxidant and the main ingredient product, add them into a mixer, and stir at a speed of 20-50 rpm for 10-20 minutes to obtain an environmentally friendly gold extraction agent, which is then vacuum-sealed and stored.

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