Method for inhibiting generation of three phases in molybdenum-rhenium extraction process

Abstract

The invention belongs to the field of molybdenum-rhenium extraction and recovery, and particularly relates to a method for inhibiting generation of three phases in a molybdenum-rhenium extraction process, which comprises the following steps: taking a sulfuric acid solution containing molybdenum and rhenium as an extraction stock solution, and carrying out n + N stage extraction by using an extraction agent: adding the extraction agent from the n + N stage, and enabling a loaded organic phase to flow out from the first stage; the extraction stock solution is added from the 1-n stages at the same time, and the raffinate flows out from the n + N stage; the water phase in the tank flows from the first stage to the (n + N) stage; the organic phase entering the 1-n stages is subjected to n-stage interval washing with a washing solution before entering: the interval washing solution flows in from the SEn stage and flows out from the SE1 stage; the organic phase flows in the following direction: the organic phase extracted from the n + 1 stage enters an SEn stage for washing and then enters an n stage for extraction; and finally, carrying out SE1-stage washing, carrying out 1-stage extraction, and finally, carrying out SE1-stage washing and 1-stage extraction. The method can effectively inhibit generation of three phases, improve the separation effect of rhenium and molybdenum and reduce the consumption of sulfuric acid.

Description

Technical Field

[0001] The invention belongs to the field of molybdenum-rhenium extraction and recovery, and in particular relates to a method for suppressing the generation of three phases in a molybdenum-rhenium extraction process. Background Art

[0002] Rhenium resources mainly exist in molybdenite in a similar phase. The pyrometallurgical smoke leaching solution of molybdenite or the wet decomposition solution of molybdenite is the main raw material for extracting rhenium. Therefore, the rhenium extraction process is also the separation process of molybdenum and rhenium. Molybdenum and rhenium are diagonal elements in the periodic table with similar chemical properties, and the separation of molybdenum and rhenium is also relatively difficult. There are many related studies. Solvent extraction is generally used to extract and separate molybdenum and rhenium.

[0003] When the rhenium content is low when the extraction method is used to recover rhenium, a larger extraction flow ratio (QA / QO) is required to increase the concentration of rhenium in the loaded organic phase and reduce the concentration of molybdenum in the loaded organic phase through competition or washing. In this large flow ratio extraction process, if the various conditions are not well controlled, the organic phase is easy to stratify and produce the third phase of extraction, making the extraction process inoperable.

[0004] Generally speaking, the way to avoid the three phases in this process is to extract under the condition of higher sulfuric acid concentration to reduce the relative saturation of molybdenum in the organic phase and further avoid the generation of three phases. In this way, when the acid in the system is low, a large amount of sulfuric acid needs to be added, resulting in a large amount of acid and alkali consumption and waste salt. Summary of the invention

[0005] The object of the present invention is to provide a method for suppressing the generation of three phases in a molybdenum-rhenium extraction process, which can effectively suppress the generation of three phases, improve the separation effect of rhenium and molybdenum, and reduce the consumption of sulfuric acid.

[0006] The technical solution to achieve the purpose of the present invention is:

[0007] A method for suppressing the generation of three phases in a molybdenum-rhenium extraction process, the method comprising:

[0008] Step (1) A sulfuric acid solution containing molybdenum and rhenium is used as an extraction stock solution, and an extraction agent is used to perform n+N stage extraction: the extraction agent is added from the n+N stage, and the loaded organic phase flows out from the 1st stage; the extraction stock solution is added from the 1st to the nth stage at the same time, and the raffinate flows out from the n+N stage; the direction of the water phase flow in the tank is from the 1st stage to the n+N stage;

[0009] In step (2), the organic phase entering each level from 1 to n is subjected to n-level interval washing with a washing liquid before entering: the interval washing liquid flows in from the SEn level and flows out from the SE1 level; the organic phase flows in the following directions: the organic phase extracted from the n+1 level enters the SEn level for washing, and then enters the nth level for extraction; then enters the SEn-1 level for washing, and then enters the n-1th level for extraction, and finally flows out after the SE1 level for washing and the 1st level for extraction.

[0010] The method further comprises:

[0011] Step (3) The loaded organic phase from the extraction stage 1 is counter-washed with the washing liquid of stage m to obtain the loaded organic phase.

[0012] The method further comprises:

[0013] In step (4), the loaded organic phase flowing out of the first stage of extraction is back-extracted with ammonia water, acidified with sulfuric acid, and returned for use as an extractant; or, the loaded organic phase after countercurrent washing is back-extracted with ammonia water, acidified with sulfuric acid, and returned for use as an extractant.

[0014] In the extraction and washing process, washing levels SE1 to SEn adopt organic phase continuity; extraction levels 2 to n+N adopt organic phase continuity; extraction level 1 adopts organic phase continuity or water phase continuity.

[0015] The composition of the extraction stock solution is: 0.1 mol / L to 2.5 mol / L sulfuric acid, 1 g / L to 10 g / L molybdenum, and 0.01 g / L to 1 g / L rhenium.

[0016] The extractant is an amine-containing extractant with a volume content of 1.5% to 15%.

[0017] The washing liquid is sulfuric acid with a concentration of 1.5 mol / L to 5 mol / L.

[0018] During the extraction process, the number of stages n=2-20, and the number of stages N=1-10.

[0019] In countercurrent washing, the number of stages m = 0 to 10.

[0020] The beneficial technical effects of the present invention are:

[0021] 1. A method for suppressing the generation of three phases in a molybdenum-rhenium extraction process provided by the present invention can be used to extract rhenium by amine extraction in a molybdenum-rhenium sulfuric acid system, thereby effectively suppressing the generation of three phases.

[0022] 2. The method for suppressing the generation of three phases in the molybdenum-rhenium extraction process provided by the present invention can reduce the consumption of sulfuric acid compared with direct acid adjustment.

[0023] 3. The method for suppressing the generation of three phases in the molybdenum-rhenium extraction process provided by the present invention can reduce the extraction of molybdenum and improve the separation effect of rhenium and molybdenum. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A flow chart of the interval washing extraction process using high acid provided by the present invention;

[0025] Figure 2 A flow chart of the external washing-interval washing combined extraction process provided by the present invention;

[0026] Figure 3 This is a process flow chart of the external washing-interval washing combined extraction and organic phase reverse extraction provided by the present invention. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0028] like Figure 1 As shown, the present invention provides a method for suppressing the generation of three phases in a molybdenum-rhenium extraction process, which specifically comprises the following steps:

[0029] Step (1) The sulfuric acid solution containing molybdenum and rhenium is used as the extraction stock solution, and the extraction agent is used for n+N stage extraction: the extraction agent is added from the n+N stage, and the loaded organic phase flows out from the 1st stage; the extraction stock solution is added from the 1st to the nth stage at the same time, and the raffinate flows out from the n+N stage. The water phase in the tank flows from the 1st stage to the n+N stage.

[0030] In step (2), the organic phase entering each level from level 1 to level n is subjected to n-level interval washing using a washing liquid before entering, with the interval washing liquid flowing in from level SEn and out from level SE1.

[0031] Specifically, in the extraction of organic phases from levels 1 to n and the interval washing process from SE1 to SEn, the organic phase flows in the following direction: the organic phase from extraction level n+1 enters level SEn for washing, and then enters level n for extraction; then enters level SEn-1 for washing, and then enters level n-1 for extraction... and finally flows out after level SE1 washing and level 1 extraction.

[0032] like Figure 2 As shown, the present invention provides a method for suppressing the generation of three phases in a molybdenum-rhenium extraction process, which specifically comprises the following steps:

[0033] Step (1) The sulfuric acid solution containing molybdenum and rhenium is used as the extraction stock solution, and the extraction agent is used for n+N stage extraction. The extraction agent is added from the n+N stage, and the loaded organic phase flows out from the 1st stage; the extraction stock solution is added from the 1st to the nth stage at the same time, and the raffinate flows out from the n+N stage. The water phase in the tank flows from the 1st stage to the n+N stage.

[0034] In step (2), the organic phase entering each of the 1 to n stages is subjected to n-stage interval washing using a washing liquid before entering. The interval washing liquid flows in from the SEn stage and flows out from the SE1 stage.

[0035] Specifically, in the extraction of organic phases from levels 1 to n and the interval washing process from SE1 to SEn, the organic phase flows in the following direction: the organic phase from extraction level n+1 enters level SEn for washing, and then enters level n for extraction; then enters level SEn-1 for washing, and then enters level n-1 for extraction... and finally flows out after level SE1 washing and level 1 extraction.

[0036] The loaded organic phase from the extraction stage 1 in step (3) is countercurrently washed with the stage M washing liquid.

[0037] Specifically, the 1st stage loaded organic phase enters the wash from SC1 stage, passes through stage m, and flows out from SCm.

[0038] like Figure 3 As shown, the present invention provides a method for suppressing the generation of three phases in a molybdenum-rhenium extraction process, which specifically comprises the following steps:

[0039] Step (1) The sulfuric acid solution containing molybdenum and rhenium is used as the extraction stock solution, and the extraction agent is used for n+N stage extraction. The extraction agent is added from the n+N stage, and the loaded organic phase flows out from the 1st stage; the extraction stock solution is added from the 1st to the nth stage at the same time, and the raffinate flows out from the n+N stage. The water phase in the tank flows from the 1st stage to the n+N stage.

[0040] In step (2), the organic phase entering each of the 1 to n stages is subjected to n-stage interval washing using a washing liquid before entering. The interval washing liquid flows in from the SEn stage and flows out from the SE1 stage.

[0041] Specifically, in the extraction of organic phases from levels 1 to n and the interval washing process from SE1 to SEn, the organic phase flows in the following direction: the organic phase from extraction level n+1 enters level SEn for washing, and then enters level n for extraction; then enters level SEn-1 for washing, and then enters level n-1 for extraction... and finally flows out after level SE1 washing and level 1 extraction.

[0042] In step (3), the loaded organic phase flowing out of the first stage of extraction is back-extracted with aqueous ammonia, acidified with sulfuric acid, and returned for use as an extractant.

[0043] like Figure 3 As shown, the present invention provides a method for suppressing the generation of three phases in a molybdenum-rhenium extraction process, which specifically comprises the following steps:

[0044] Step (1) The sulfuric acid solution containing molybdenum and rhenium is used as the extraction stock solution, and the extraction agent is used for n+N stage extraction. The extraction agent is added from the n+N stage, and the loaded organic phase flows out from the 1st stage; the extraction stock solution is added from the 1st to the nth stage at the same time, and the raffinate flows out from the n+N stage. The water phase in the tank flows from the 1st stage to the n+N stage.

[0045] In step (2), the organic phase entering each of the 1 to n stages is subjected to n-stage interval washing using a washing liquid before entering. The interval washing liquid flows in from the SEn stage and flows out from the SE1 stage.

[0046] Specifically, in the extraction of organic phases from levels 1 to n and the interval washing process from SE1 to SEn, the organic phase flows in the following direction: the organic phase from extraction level n+1 enters level SEn for washing, and then enters level n for extraction; then enters level SEn-1 for washing, and then enters level n-1 for extraction... and finally flows out after level SE1 washing and level 1 extraction.

[0047] In step (3), the loaded organic phase flowing out of the first stage of extraction is countercurrently washed with the m-stage washing liquid to obtain a loaded organic phase.

[0048] Specifically, the 1st stage loaded organic phase enters the wash from SC1 stage, passes through stage m, and flows out from SCm.

[0049] The loaded organic phase after countercurrent washing in step (4) is back-extracted with ammonia water, acidified with sulfuric acid, and returned for use as an extractant.

[0050] In the above method, the total flow rates of the solutions are: organic phase QO, extraction solution flow rate QA, and detergent flow rate QS; wherein the flow rate of the newly added extraction solution at each level 1 to n is QA / n.

[0051] In the above extraction and washing process, washing stages SE1 to SEn are continuous with organic phase; extraction stages 2 to n+N are continuous with organic phase; and extraction stage 1 is continuous with organic phase or continuous with water phase.

[0052] In the above method, the extraction solution is a sulfuric acid system solution containing molybdenum and rhenium, and a sulfuric acid conversion leaching solution of molybdenite; the composition of the extraction solution: contains 0.1 mol / L to 2.5 mol / L sulfuric acid, 1 g / L to 10 g / L molybdenum, and 0.01 g / L to 1 g / L rhenium.

[0053] The washing liquid for interval washing in the above method is highly concentrated sulfuric acid, and the composition of the washing liquid is: containing 1.5 mol / L to 5 mol / L sulfuric acid.

[0054] The extractant composition contains 1.5% to 15% (V / V) of amine extractant.

[0055] The extraction stage number n of the above method is 2 to 20. The value of n is required to be: 1) the amount of molybdenum carried in the loaded organic phase after high acid washing, 2) the amount of molybdenum carried by the added 1 / n extraction solution, and 3) the amount of molybdenum carried by the previous aqueous phase. The sum of the molybdenum of the three is sufficient to ensure that no third phase will be formed after the two phases are mixed.

[0056] The extraction stage number N is 1 to 10. The value of N is required to be such that the total rhenium concentration in the raffinate tail liquid meets the recovery rate requirement.

[0057] The loaded organic phase from the first stage of the extraction is subjected to m-stage countercurrent external washing, then subjected to ammonia water back extraction, and then acidified with sulfuric acid and returned as an extractant, wherein m=0-10.

[0058] The washing liquid for the above-mentioned interval washing can be fresh sulfuric acid or washing liquid from external washing.

[0059] The washing liquid from the above-mentioned interval washing can be returned to the conversion leaching, and can also be used for other purposes, such as molybdenum precipitation and acid adjustment.

[0060] Example 1

[0061] The sulfuric acid conversion leachate of a molybdenite has a rhenium concentration of 0.2g / L, a molybdenum concentration of 5g / L, and a sulfuric acid concentration of 120g / L. The extraction is carried out using an extractant containing 7.5% N235. During the extraction process, the organic phase is washed with sulfuric acid, and the sulfuric acid concentration is 4mol / L. The organic phase flow rate is 1m 3 / h, the flow rate of the extraction liquid is 5m 3 / h, the washing liquid flow rate is 2m 3 / h. The total number of extraction stages is 12, the extractant is added at the 12th stage, and the 1st stage outflow carries the organic phase; the extraction stock solution is added at stages 1 to 8, and the addition amount is 1m 3 / h, and the residue is extracted at stage 12. The organic phase before entering stage 8 to stage 1 in the extraction process is washed with sulfuric acid to obtain the final washing liquid to precipitate molybdenum and adjust the acid.

[0062] The organic phases of extraction levels 1 to 12 are continuous, and the organic phases are continuous in both washings. The obtained loaded organic phase contains 0.8 g / L of rhenium and 2.8 g / L of molybdenum, and the raffinate contains 1.1 g / L of molybdenum. The molybdenum concentration of each level of organic phase is the highest at 2.8 g / L. The phase separation is good during the extraction process, and no third phase is generated. After the loaded organic phase is back-extracted with ammonia water, it is acidified with sulfuric acid and returned for use as an extractant.

[0063] Example 2

[0064] The sulfuric acid conversion leachate of a molybdenite has a rhenium concentration of 0.2g / L, a molybdenum concentration of 5g / L, and a sulfuric acid concentration of 120g / L. The extraction is carried out using an extractant containing 10% N235. The organic phase after extraction and the organic phase during extraction are washed with sulfuric acid with a sulfuric acid concentration of 3mol / L. The organic phase flow rate is 1m 3 / h, the flow rate of the extraction liquid is 8m 3 / h, the washing liquid flow rate is 2m 3 / h. The total number of extraction stages is 12, the extractant is added at the 12th stage, and the 1st stage outflow carries the organic phase; the extraction stock solution is added at stages 1 to 8, and the addition amount is 1m 3 / h, and the 12th stage extracts the residue. The sulfuric acid washing liquid washes the organic phase before entering the 8th to 1st stage during the extraction process, and the loaded organic phase is countercurrently washed with 3-stage sulfuric acid washing liquid to obtain the final washing liquid to convert and leach molybdenite.

[0065] The organic phases of extraction levels 1 to 12 are continuous, and the organic phases are continuous in both washings. The obtained loaded organic phase contains 1.4 g / L of rhenium and 2.45 g / L of molybdenum, and the raffinate contains 1.9 g / L of molybdenum. The molybdenum concentration of each level of organic phase is up to 4.2 g / L. The phase separation is good during the extraction process, and no third phase is generated. After the loaded organic phase is back-extracted with ammonia water, it is acidified with sulfuric acid and returned for use as an extractant.

[0066] Example 3

[0067] A sulfuric acid system solution containing molybdenum and rhenium, with a rhenium concentration of 0.1g / L, a molybdenum concentration of 3g / L, and a sulfuric acid concentration of 120g / L, is extracted with an extractant containing 7.5% N235. The organic phase after extraction and the organic phase during the extraction process are washed with sulfuric acid, and the sulfuric acid concentration is 4mol / L. The organic phase flow rate is 1m3 / h, the flow rate of the extraction stock solution is 10m3 / h, and the flow rate of the washing liquid is 1m3 / h. The total number of extraction stages is 9, the extractant is added at the 9th stage, and the organic phase is loaded at the 1st stage; the extraction stock solution is added at stages 1 to 5, respectively, with an addition amount of 2m3 / h, and the residue is extracted at the 9th stage. The sulfuric acid washing liquid washes the organic phase before entering the 5th to 1st stage during the extraction process, and the loaded organic phase is countercurrently washed with a 2-stage sulfuric acid washing liquid to obtain the final washing liquid, and the precipitated molybdenum is acidified.

[0068] The organic phases of levels 2 to 9 were extracted continuously, the aqueous phase of level 1 was extracted continuously, and the organic phases of both washes were continuous. The obtained loaded organic phase contained 0.9 g / L of rhenium and 1.4 g / L of molybdenum, and the raffinate contained 1.4 g / L of molybdenum. The molybdenum concentration of each level of organic phase was up to 3 g / L. The phase separation was good during the extraction process, and no third phase was generated. After the loaded organic phase was back-extracted with ammonia water, it was acidified with sulfuric acid and returned for use as an extractant.

[0069] The present invention is described in detail above with reference to the accompanying drawings and embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The contents not described in detail in the present invention can adopt the existing technology.

Claims

1. A method for suppressing the generation of three phases in a molybdenum-rhenium extraction process, characterized in that: The method comprises: Step (1) A sulfuric acid solution containing molybdenum and rhenium is used as an extraction stock solution, and an extraction agent is used to perform n+N stage extraction: the extraction agent is added from the n+N stage, and the loaded organic phase flows out from the 1st stage; the extraction stock solution is added from the 1st to the nth stage at the same time, and the raffinate flows out from the n+N stage; the direction of the water phase flow in the tank is from the 1st stage to the n+N stage; In step (2), the organic phase entering each level from 1 to n is subjected to n-level interval washing with a washing liquid before entering: the interval washing liquid flows in from the SEn level and flows out from the SE1 level; the organic phase flows in the following directions: the organic phase extracted from the n+1 level enters the SEn level for washing, and then enters the nth level for extraction; then enters the SEn-1 level for washing, and then enters the n-1th level for extraction, and finally flows out after the SE1 level for washing and the 1st level for extraction.

2. The method for suppressing the generation of three phases in a molybdenum-rhenium extraction process according to claim 1, characterized in that: The method further comprises: In step (3), the loaded organic phase flowing out of the first extraction stage is countercurrently washed with the m-stage washing liquid to obtain a loaded organic phase.

3. The method for suppressing the generation of three phases in a molybdenum-rhenium extraction process according to any one of claims 1 or 2, characterized in that: The method further comprises: In step (4), the loaded organic phase flowing out of the first stage of extraction is back-extracted with ammonia water, acidified with sulfuric acid, and returned for use as an extractant; or, the loaded organic phase after countercurrent washing is back-extracted with ammonia water, acidified with sulfuric acid, and returned for use as an extractant.

4. The method for suppressing the generation of three phases in a molybdenum-rhenium extraction process according to claim 1, characterized in that: In the extraction and washing process, washing levels SE1 to SEn adopt organic phase continuity; extraction levels 2 to n+N adopt organic phase continuity; extraction level 1 adopts organic phase continuity or water phase continuity.

5. The method for suppressing the generation of three phases in a molybdenum-rhenium extraction process according to claim 1, characterized in that: The composition of the extraction stock solution is: 0.1 mol / L to 2.5 mol / L sulfuric acid, 1 g / L to 10 g / L molybdenum, and 0.01 g / L to 1 g / L rhenium.

6. The method for suppressing the generation of three phases in a molybdenum-rhenium extraction process according to claim 1, characterized in that: The extractant is an amine-containing extractant with a volume content of 1.5% to 15%.

7. The method for suppressing the generation of three phases in a molybdenum-rhenium extraction process according to claim 1, characterized in that: The washing liquid is sulfuric acid with a concentration of 1.5 mol / L to 5 mol / L.

8. The method for suppressing the generation of three phases in a molybdenum-rhenium extraction process according to claim 1, characterized in that: During the extraction process, the number of stages n=2-20, and the number of stages N=1-10.

9. The method for suppressing the generation of three phases in a molybdenum-rhenium extraction process according to claim 2, characterized in that: In countercurrent washing, the number of stages m = 0 to 10.

Images