Method for synchronously removing lead and arsenic from solution containing nickel, lead and arsenic

Abstract

The invention provides a method for synchronously removing lead and arsenic from a solution containing nickel, lead and arsenic, which comprises the following steps: oxidizing the solution containing nickel, lead and arsenic to obtain an oxidized material; the oxidized material and barium sulfide are subjected to impurity removal treatment, and a purified material is obtained. The method provided by the invention can realize synchronous precipitation removal of lead and arsenic in the anolyte, the reaction process is short, the time is short, the slag amount is small, the production efficiency can be greatly improved, and the impurity removal cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of waste liquid separation, and in particular to a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. Background Art

[0002] In the process of electrolytic nickel production, the anode plate material used usually contains Pb or As elements, and the anode liquid is acidic, which causes the anode plate to corrode slowly, and impurities Pb and As will enter the anode liquid. In order to obtain high-quality nickel plates, the anode liquid must undergo strict lead and arsenic removal operations before returning to the circulation system and re-entering the electrolytic cell.

[0003] At present, the removal of lead and arsenic from the anode liquid is usually carried out in steps. The barium carbonate co-precipitation method is often used for lead removal, while the iron salt precipitation method is often used for arsenic removal. However, the iron salt precipitation method will introduce new impurity iron, which requires further iron removal later, and the process is complicated.

[0004] Although there are studies on the use of resin and adsorption methods to remove lead and arsenic, the resin method usually cannot remove both impurities at the same time, and the resin is expensive and difficult to regenerate. The adsorption method consumes a large amount of adsorbent and the discarded adsorbent is classified as hazardous waste, which has a high treatment cost.

[0005] There are some other related studies, such as CN119194538A discloses a method for removing lead and supplementing nickel from an electrolytic nickel anolyte, which discloses a method for purifying and removing lead from an anolyte of a pure sulfuric acid system, wherein the electrolytic anolyte is added to a refined nickel sulfate degreasing liquid and a nickel carbonate slurry, air is introduced, the temperature is controlled, and the anolyte enters an acid-soluble lead removal tank for acid dissolution, and then the acid-soluble liquid is filtered by an acid-soluble filter press, the obtained primary filtrate is pumped into a precision filter, the obtained secondary filtrate enters a secondary filtrate storage tank, the secondary filtrate is pumped into a cathode liquid tank by a secondary filtrate delivery pump, and the obtained cathode liquid enters the electrolytic process as the cathode liquid of the electrolytic tank. However, this method has a long process and can only remove lead alone, and cannot remove lead and arsenic simultaneously.

[0006] CN117107341A discloses a method for regenerating and circulating an electrodeposited nickel anolyte, specifically disclosing that the electrodeposited nickel anolyte is used in the stripping section of a nickel sulfate extraction and enrichment line for stripping a nickel-loaded P507 extractant, which can consume hydrogen ions in the anolyte and replenish nickel sulfate, and at the same time avoid the loss and waste of nickel in the stripping process of the nickel-loaded P507 extractant. However, this method requires the use of an organic extractant, which is costly and complicated to subsequently treat the organic waste liquid.

[0007] Therefore, it is necessary to develop a low-cost, fast and deep treatment method for electrolytic nickel anolyte. Summary of the invention

[0008] In order to solve the above technical problems, the present invention provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. By adopting the method of first oxidizing the nickel-lead-arsenic solution and then reacting it with barium sulfide, the deep removal of lead and arsenic in the nickel-lead-arsenic solution can be achieved with a short operation process, thereby solving the problems of the current process for removing lead and arsenic from electrolytic nickel anode liquid that is complex in operation, time-consuming, incomplete or costly.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] The present invention provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution, the method comprising the following steps:

[0011] The nickel-lead-arsenic solution is subjected to oxidation treatment to obtain an oxidized material;

[0012] The oxidized material is treated with barium sulfide to remove impurities to obtain a purified material.

[0013] The present invention first performs oxidation treatment to oxidize low-valent arsenic ions in the nickel-lead-arsenic solution into high-valent arsenate ions, and then reacts the oxidized material with barium sulfide, wherein the following reaction equation occurs between the barium sulfide and the oxidized material:

[0014] Pb 2+ +S 2- =PbS↓

[0015] 2(AsO 4 ) 3- +3Ba 2+ =Ba 3 (AsO 4 ) 2 ↓

[0016] Ba 2+ +SO 4 2- =BaSO 4 ↓

[0017] It can be seen from the above reaction equation that after adding barium sulfide, the impurity Pb ​​is mainly precipitated in the form of lead sulfide, and the impurity As is mainly precipitated in the form of barium arsenate. Because the sulfate system is rich in sulfate ions, the excess barium ions will be precipitated as barium sulfate, which will not cause excessive residual barium ions in the solution, thereby achieving the simultaneous removal of arsenic and lead without the introduction of organic matter and without generating additional wastewater. The process is environmentally friendly and simple, and has broad application prospects.

[0018] Preferably, the nickel content in the nickel-lead-arsenic solution is 60-80 g / L.

[0019] Preferably, the lead content in the nickel-lead-arsenic solution is 5-20 mg / L.

[0020] Preferably, the arsenic content in the nickel-lead-arsenic solution is 0.1-2 mg / L.

[0021] Preferably, the anions in the nickel-lead-arsenic containing solution include sulfate.

[0022] Preferably, the nickel-lead-arsenic containing solution also includes a third metal element.

[0023] Preferably, the third metal element includes any one of cobalt, iron or copper, or a combination of at least two of them.

[0024] Preferably, the cobalt content in the nickel-lead-arsenic containing solution is 0.1-0.5 mg / L.

[0025] Preferably, the iron content in the nickel-lead-arsenic containing solution is 0.01-1 mg / L.

[0026] Preferably, the copper content in the nickel-lead-arsenic containing solution is 0.01-0.5 mg / L.

[0027] Preferably, the nickel-lead-arsenic containing solution is an electrolytic nickel anode solution.

[0028] Preferably, the pH of the nickel-lead-arsenic containing solution is 1.0-2.0.

[0029] Preferably, the pH of the oxidation treatment is 1.0 to 2.0.

[0030] Preferably, the temperature of the oxidation treatment is 30-80°C.

[0031] Preferably, the oxidation treatment comprises: treating the nickel-lead-arsenic containing solution with an oxidant.

[0032] Preferably, the oxidant comprises any one of oxygen, hydrogen peroxide or sodium persulfate, or a combination of at least two thereof.

[0033] Preferably, the molar amount of the oxidant is 2 to 5 times the molar amount of arsenic in the nickel-lead-arsenic solution.

[0034] Preferably, the ratio of the molar amount of the barium sulfide to the total molar amount of lead and arsenic in the oxidized material is 5 to 10:1.

[0035] It is worth noting that the amount of barium sulfide added in the present invention is not simply to be enriched on the basis of the stoichiometric ratio. Researchers generally believe that it is sufficient to be enriched by about 20% near the stoichiometric ratio, while the present invention needs to reach several times to have a better simultaneous removal effect of lead and arsenic. The inventors have found that even if the amount of barium sulfide added is about 2 times or even 4 times the stoichiometric ratio, it is difficult to achieve a better removal effect. This is because on the one hand, the nickel and sulfate content in the system is high, and competitive reactions will occur, while the content of lead and arsenic itself is in the milligram level, and the overall addition amount of barium sulfide itself is not high, resulting in the addition amount of the precipitant cannot be measured by conventional methods. Preferably, the pH of the impurity removal treatment is 3.0-5.0.

[0036] The present invention preferably controls the pH of the impurity removal treatment within the above range, which can better remove lead and arsenic in the nickel-lead-arsenic solution while reducing the loss of nickel.

[0037] Preferably, the temperature of the impurity removal treatment is 30-60°C.

[0038] Preferably, the time for the impurity removal treatment is 20 to 60 minutes.

[0039] Compared with the prior art, the present invention has at least the following beneficial effects:

[0040] (1) The method for simultaneous removal of lead and arsenic from a nickel-lead-arsenic solution provided by the present invention can achieve simultaneous precipitation and removal of Pb and As in the anolyte, with a short reaction process, fast time, and small amount of slag, which can greatly improve production efficiency and reduce impurity removal costs.

[0041] (2) The method for simultaneous removal of lead and arsenic from a nickel-lead-arsenic solution provided by the present invention has an extremely low impurity content after purification after impurities removal, and deep removal of Pb and As can be achieved under preferred conditions, wherein the mass content of Pb can be reduced to within 0.05 mg / L, the mass content of As can be reduced to within 0.1 mg / L, and the loss of nickel is only within 0.05%.

[0042] (3) The method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution provided by the present invention can, under preferred conditions, allow the composition index of the electrolytic nickel plate to meet the Ni9999 standard after the purified material is circulated to the electrolytic cell. DETAILED DESCRIPTION

[0043] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0044] It should be understood that, in the description of the present invention, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0045] The nickel-lead-arsenic solution used as the anode liquid for nickel electroplating, in which the presence of lead and arsenic will result in the anode liquid being unable to be recirculated to the electrolytic cell, is therefore not only a method for removing lead and arsenic from the solution, but is also a method for separating nickel and lead-arsenic from the solution. How to remove lead and arsenic with simple, low-cost steps while avoiding the loss of nickel is a technical problem that needs to be solved by the present invention.

[0046] To this end, the present invention provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution, the method comprising the following steps:

[0047] The nickel-lead-arsenic solution is subjected to oxidation treatment to obtain an oxidized material;

[0048] The oxidized material is treated with barium sulfide to remove impurities to obtain a purified material.

[0049] The nickel in the nickel-lead-arsenic solution of the present invention is Ni 2+ Lead exists in the form of Pb 2+ Arsenic exists in the form of AsO 4 3- and AsO 3 3- The anion in the solution is sulfate ion. As arsenic and lead ions are difficult to remove simultaneously, the currently used extraction, adsorption or step-by-step precipitation methods have problems such as complex processes, introduction of impurity ions, and organic pollution.

[0050] The present invention hopes to separate lead and arsenic by an inorganic method. After many studies, it is found that lead, arsenic and nickel can be separated by a comprehensive method of first oxidation and then simultaneous precipitation. By selecting a precipitant, it is found that barium sulfide can dissociate into S in an aqueous solution. 2- and Ba 2+ , where S 2- Can be used with Pb 2+ The reaction forms PbS precipitate, Ba 2+ Can be used with (AsO 4 ) 3- The reaction forms Ba 3 (AsO 4 ) 2 Precipitation, and because the anion in the solution system of the present invention is sulfate, the excess Ba 2+ Can be BaSO4 thus preventing the barium element from remaining in the solution system.

[0051] The method provided by the present invention can separate nickel from lead and arsenic by adding only inorganic substances, and the overall process flow is short and the operation is simple.

[0052] In some embodiments, the nickel content in the nickel-lead-arsenic solution is 60-80 g / L, for example, it can be 60 g / L, 63 g / L, 65 g / L, 67 g / L, 69 g / L, 72 g / L, 74 g / L, 76 g / L, 78 g / L or 80 g / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0053] In some embodiments, the lead content in the nickel-lead-arsenic solution is 5 to 20 mg / L, for example, it can be 5 mg / L, 7 mg / L, 9 mg / L, 10 mg / L, 12 mg / L, 14 mg / L, 15 mg / L, 17 mg / L, 19 mg / L or 20 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0054] In some embodiments, the arsenic content in the nickel-lead-arsenic solution is 0.1-2 mg / L, for example, it can be 0.1 mg / L, 0.4 mg / L, 0.6 mg / L, 0.8 mg / L, 1 mg / L, 1.2 mg / L, 1.4 mg / L, 1.6 mg / L, 1.8 mg / L or 2 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0055] In certain embodiments, the anions in the nickel-lead-arsenic containing solution include sulfate.

[0056] In certain embodiments, the nickel-lead-arsenic containing solution further comprises a third metal element.

[0057] In certain embodiments, the third metal element includes any one of cobalt, iron or copper, or a combination of at least two of them, wherein typical but non-limiting combinations are a combination of cobalt and iron, a combination of copper and iron, a combination of cobalt and copper, and a combination of copper, cobalt and iron.

[0058] In certain embodiments, the cobalt content in the nickel-lead-arsenic solution is 0.1-0.5 mg / L, for example, it can be 0.1 mg / L, 0.15 mg / L, 0.19 mg / L, 0.24 mg / L, 0.28 mg / L, 0.33 mg / L, 0.37 mg / L, 0.42 mg / L, 0.46 mg / L or 0.5 mg / L, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0059] In some embodiments, the iron content in the nickel-lead-arsenic solution is 0.01-1 mg / L, for example, it can be 0.01 mg / L, 0.12 mg / L, 0.23 mg / L, 0.34 mg / L, 0.45 mg / L, 0.56 mg / L, 0.67 mg / L, 0.78 mg / L, 0.89 mg / L or 1 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0060] In certain embodiments, the copper content in the nickel-lead-arsenic solution is 0.01 to 0.5 mg / L, for example, it can be 0.01 mg / L, 0.07 mg / L, 0.12 mg / L, 0.18 mg / L, 0.23 mg / L, 0.29 mg / L, 0.34 mg / L, 0.4 mg / L, 0.45 mg / L or 0.5 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are equally applicable.

[0061] The cobalt in the nickel-lead-arsenic solution of the present invention is Co 2+ The cobalt element will react with S after adding barium sulfide. 2- The reaction produces CoS precipitation and consumes a certain amount of precipitant.

[0062] Iron 2+ and / or Fe 3+ It exists in the form of Fe 3+ After adding barium sulfide, the iron element is removed in the form of FeS precipitation.

[0063] Copper 2+ In the form of copper, after adding barium sulfide, the copper element will form CuS precipitation and be removed.

[0064] That is, the method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution provided by the present invention is essentially a method for deep impurity removal of an electrolytic nickel anode liquid, which can not only simultaneously remove lead and arsenic, but also simultaneously remove cobalt, iron and copper therein.

[0065] In certain embodiments, the nickel-lead-arsenic containing solution is an electrodeposition nickel anolyte.

[0066] In some embodiments, the pH of the nickel-lead-arsenic solution is 1.0-2.0, for example, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2.0, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0067] In certain embodiments, the oxidation treatment comprises: treating the nickel-lead-arsenic containing solution with an oxidant.

[0068] In certain embodiments, the oxidant comprises any one of oxygen, hydrogen peroxide or sodium persulfate, or a combination of at least two thereof, wherein typical but non-limiting combinations are a combination of oxygen and hydrogen peroxide, a combination of sodium persulfate and hydrogen peroxide, a combination of oxygen and sodium persulfate, and a combination of sodium persulfate, oxygen and hydrogen peroxide.

[0069] The electrolytic nickel anolyte of the present invention contains sodium ions, which can act as a conductive agent. Therefore, the introduction of a small amount of sodium ions will not affect the circulation of the electrolytic nickel anolyte, and sodium persulfate can be used as an oxidant.

[0070] In certain embodiments, the molar amount of the oxidant is 2 to 5 times the molar amount of arsenic in the nickel-lead-arsenic solution, for example, 2 times, 2.4 times, 2.7 times, 3 times, 3.4 times, 3.7 times, 4 times, 4.4 times, 4.7 times or 5 times, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0071] In certain embodiments, the reaction apparatus used for the oxidation treatment is not particularly limited and can be carried out using a reaction apparatus commonly used by those skilled in the art, such as a reactor such as a reaction kettle, a bubbling tower or a packed tower.

[0072] In certain embodiments, when hydrogen peroxide is used as the oxidant, a mass concentration of 20 to 30 wt% hydrogen peroxide is generally used, for example, 20 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt% or 30 wt%, etc., but not limited to the values ​​listed, other values ​​not listed in the range are also applicable. When sodium persulfate is used as the oxidant, solid phase sodium persulfate can be directly added.

[0073] In certain embodiments, the pH of the oxidation treatment is 1.0 to 2.0, for example, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2.0, etc., but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0074] In certain embodiments, the temperature of the oxidation treatment is 30-80°C, for example, 30°C, 35°C, 40°C, 42°C, 45°C, 50°C, 55°C, 58°C, 60°C, 65°C, 70°C, 75°C or 80°C, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0075] The oxidation treatment of the present invention can be carried out under stirring conditions, but the present invention does not impose any particular limitation on the stirring speed, and the oxidation treatment can be carried out at a stirring speed well known to those skilled in the art.

[0076] In certain embodiments, the ratio of the molar amount of the barium sulfide to the total molar amount of lead and arsenic in the oxidized material is 5 to 10:1, for example, 5:1, 5.6:1, 6.2:1, 6.7:1, 7.3:1, 7.8:1, 8.4:1, 8.9:1, 9.5:1 or 10:1, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0077] The present invention preferably controls the molar amount of barium sulfide within the above range, which can avoid excessive use of barium sulfide while ensuring deep removal of lead and arsenic.

[0078] In certain embodiments, the particle size of the barium sulfide is 200-800 mesh, for example, 200 mesh, 250 mesh, 300 mesh, 350 mesh, 400 mesh, 450 mesh, 500 mesh, 550 mesh, 600 mesh, 650 mesh, 700 mesh, 750 mesh or 800 mesh, but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0079] Those skilled in the art know that, since barium sulfide has a low solubility in water, the present invention preferably uses powdered barium sulfide with a particle size within the above range to react with the oxidized material. This not only makes the reaction more uniform and rapid, and removes impurities more thoroughly, but also avoids excessive waste of barium sulfide.

[0080] In certain embodiments, the pH of the impurity removal treatment is 3.0 to 5.0, for example, 3.0, 3.3, 3.5, 3.7, 3.9, 4.2, 4.4, 4.6, 4.8 or 5.0, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0081] The present invention preferably controls the pH of the impurity removal treatment within the above range, which can better improve the impurity removal effect.

[0082] In certain embodiments, the temperature of the impurity removal treatment is 30-60°C, for example, 30°C, 34°C, 37°C, 40°C, 44°C, 47°C, 50°C, 54°C, 57°C or 60°C, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0083] In certain embodiments, the time for the impurity removal treatment is 20 to 60 min, for example, it can be 20 min, 25 min, 29 min, 34 min, 38 min, 43 min, 47 min, 52 min, 56 min or 60 min, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0084] In certain embodiments, the purified material can be returned to the electrolytic cell for recycling as cathode liquid after the Ni concentration and additives are supplemented.

[0085] In certain embodiments, the nickel concentration in the solution after nickel supplementation is 80 to 100 g / L, for example, it can be 80 g / L, 85 g / L, 88 g / L, 90 g / L, 95 g / L, 98 g / L or 100 g / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0086] The present invention has no particular limitation on the additives added to the purified material, and additives familiar to those skilled in the art may be used for addition. In certain embodiments, the additives include boric acid, sodium sulfate, sodium dodecyl sulfate, and the like.

[0087] As one embodiment of the present invention, a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution is provided, the method comprising the following steps:

[0088] Under the conditions of pH 1.0-2.0 and temperature 30-80°C, the nickel-lead-arsenic solution is oxidized under the action of an oxidant to obtain an oxidized material, wherein the oxidant includes any one of oxygen, hydrogen peroxide or sodium persulfate or a combination of at least two thereof, and the molar amount of the oxidant is 2-5 times the molar amount of arsenic in the nickel-lead-arsenic solution.

[0089] The oxidized material and barium sulfide are subjected to impurity removal treatment for 20 to 60 minutes at a pH of 3.0 to 5.0 and a temperature of 30 to 60° C., wherein the ratio of the molar amount of barium sulfide to the total molar amount of lead and arsenic in the oxidized material is 5 to 10:1, and solid-liquid separation is performed to obtain a purified material.

[0090] The following is a detailed description with reference to specific embodiments.

[0091] Example 1

[0092] This embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution, the method comprising the following steps:

[0093] A nickel-lead-arsenic solution (electrolytic nickel anode solution, wherein Ni: 75 g / L; Co: 0.4 mg / L; Fe: 0.5 mg / L; Pb: 15 mg / L; As: 0.5 mg / L; Cu: 0.4 mg / L) is pumped into a reaction kettle, and a 25 wt% hydrogen peroxide solution is added, wherein the molar amount of hydrogen peroxide is 3.5 times the molar amount of arsenic in the nickel-lead-arsenic solution, and an oxidation treatment is performed under the conditions of pH 1.5 and temperature 60°C to obtain an oxidized material.

[0094] The oxidized material and barium sulfide are subjected to impurity removal treatment for 40 minutes at a pH of 4.0 and a temperature of 50° C., wherein the ratio of the molar amount of barium sulfide to the total molar amount of lead and arsenic in the oxidized material is 8:1, and filtered to obtain a liquid phase, which is the purified material.

[0095] Example 2

[0096] This embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution, the method comprising the following steps:

[0097] A nickel-lead-arsenic solution (electrolytic nickel anode solution, wherein Ni: 80 g / L; Co: 0.1 mg / L; Pb: 20 mg / L; As: 2 mg / L) is pumped into a reactor, and a 20 wt% hydrogen peroxide solution is added, wherein the molar amount of hydrogen peroxide is 5 times the molar amount of arsenic in the nickel-lead-arsenic solution, and an oxidation treatment is performed under the conditions of pH 1.0 and temperature 30°C to obtain an oxidized material.

[0098] The oxidized material and barium sulfide are treated for impurity removal at a pH of 5.0 and a temperature of 60° C. for 20 minutes, wherein the ratio of the molar amount of barium sulfide to the total molar amount of lead and arsenic in the oxidized material is 5:1, and filtered to obtain a liquid phase, which is the purified material.

[0099] Example 3

[0100] This embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution, the method comprising the following steps:

[0101] A nickel-lead-arsenic solution (electrolytic nickel anode solution, wherein Ni: 60 g / L; Co: 0.5 mg / L; Fe: 1 mg / L; Pb: 5 mg / L; As: 0.1 mg / L; Cu: 0.5 mg / L) is pumped into a reactor, and oxygen is introduced, wherein the molar amount of oxygen is twice the molar amount of arsenic in the nickel-lead-arsenic solution, and oxidation treatment is carried out under the conditions of pH 2.0 and temperature 80°C to obtain an oxidized material.

[0102] The oxidized material and barium sulfide are treated for impurity removal at a pH of 3.0 and a temperature of 30° C. for 60 minutes, wherein the ratio of the molar amount of barium sulfide to the total molar amount of lead and arsenic in the oxidized material is 10:1, and filtered to obtain a liquid phase, which is the purified material.

[0103] Example 4

[0104] This embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as that of Embodiment 1 except that hydrogen peroxide is replaced by an equimolar amount of sodium persulfate, and thus will not be described in detail herein.

[0105] Example 5

[0106] The present embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as that of Embodiment 1 except that the ratio of the molar amount of barium sulfide to the total molar amount of lead and arsenic in the oxidized material is 4:1, and thus will not be described in detail.

[0107] Example 6

[0108] The present embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as that of Embodiment 1 except that the ratio of the molar amount of barium sulfide to the total molar amount of lead and arsenic in the oxidized material is 12:1, and thus will not be described in detail.

[0109] Example 7

[0110] This embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as that of Embodiment 1 except that the pH value of the impurity removal treatment is 2.5, and details thereof will not be repeated here.

[0111] Example 8

[0112] This embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as that of Embodiment 1 except that the pH value of the impurity removal treatment is 6.0, and details thereof will not be repeated here.

[0113] Example 9

[0114] This embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as Embodiment 1 except that the molar amount of the oxidant is 1.5 times the molar amount of arsenic in the nickel-lead-arsenic solution, and will not be described again.

[0115] Example 10

[0116] This embodiment provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as Embodiment 1 except that the molar amount of the oxidant is 6 times the molar amount of arsenic in the nickel-lead-arsenic solution, and will not be described again.

[0117] Comparative Example 1

[0118] This comparative example provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as Example 1 except that no oxidation treatment is performed, and details thereof will not be repeated here.

[0119] Comparative Example 2

[0120] This comparative example provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as Example 1 except that barium sulfide is replaced by equimolar amounts of barium carbonate and sodium sulfide, and will not be described in detail here.

[0121] Comparative Example 3

[0122] This comparative example provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as Example 1 except that barium sulfide is replaced by sodium sulfide, and details thereof will not be repeated here.

[0123] Comparative Example 4

[0124] This comparative example provides a method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution. The method is the same as Example 1 except that barium sulfide is replaced by barium carbonate, and details thereof will not be repeated here.

[0125] Test method: Use ICP to test the mass concentration of each ion in the solution.

[0126] The nickel loss rate is recorded as (1-nickel mass content in the purified material / nickel mass content in the original nickel-lead-arsenic solution)*100%.

[0127] The test results of the above embodiments and comparative examples are shown in Table 1.

[0128] Table 1

[0129]

[0130] From Table 1 we can see that:

[0131] (1) It can be seen from Examples 1 to 4 that the method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution provided by the present invention has the advantages of a short reaction process, a fast reaction time and a small amount of slag, and after impurities are removed, the arsenic content is reduced to less than 0.1 mg / L, the lead content is reduced to less than 0.05 mg / L, and the nickel loss rate is only less than 0.05%.

[0132] (2) Combining Example 1 and Examples 5-6, it can be seen that the ratio of the molar amount of barium sulfide to the total molar amount of lead and arsenic in the oxidized material in Example 1 is 8:1, while the ratios of the molar amount of barium sulfide to the total molar amount of lead and arsenic in the oxidized material in Examples 5-6 are 4:1 and 12:1, respectively. In Example 1, the nickel loss rate is only 0.035%, and the lead content in the purified material is only 0.04 mg / L, and the arsenic content in the purified material is only 0.06 mg / L, while the lead content in the purified material of Example 5 is 100 mg / L. The content of barium sulfide in the present invention is 0.22 mg / L, and the content of arsenic is 0.12 mg / L, which makes it difficult to produce nickel electrolytically deposited plates of Ni9999 standard after circulating to the cathode liquid; the loss rate of nickel in Example 6 reaches 0.055%, which is significantly increased compared with Example 1, and the removal effect of arsenic and lead is not significantly improved. This shows that the present invention preferably controls the ratio of the molar amount of barium sulfide to the total molar amount of lead and arsenic in the oxidized material within a reasonable range, has a better impurity removal effect, and can effectively reduce the loss of nickel.

[0133] (3) Combining Example 1 and Examples 7 to 8, it can be seen that the pH of the impurity removal treatment in Example 1 is 4.0, while the pH of the impurity removal treatment in Examples 7 to 8 is 2.5 and 6.0 respectively. In Example 1, the nickel loss rate is only 0.035%, and the lead content in the purified material is only 0.04 mg / L, and the arsenic content in the purified material is only 0.06 mg / L, while the lead content in the purified material of Example 7 reaches 1.25 mg / L, and the arsenic content reaches 0.24 mg / L, which cannot be circulated to the cathode liquid; and the nickel loss rate in Example 8 reaches 0.150%, which is significantly increased compared with Example 1. This shows that the impurity removal treatment of the present invention needs to be carried out under suitable pH conditions in order to have an excellent effect of separating nickel from lead and arsenic.

[0134] (4) It can be seen from Example 1 and Examples 9 to 10 that when the amount of oxidant is too low, the effect on arsenic removal is more obvious, and the arsenic removal effect is significantly reduced. When the amount of oxidant is too high, the improvement in the lead and arsenic removal effect is not obvious, and there is no need to add excessive amount.

[0135] (5) Based on Example 1 and Comparative Examples 1 to 4, it can be seen that in Comparative Example 1, no oxidation treatment was performed, resulting in that arsenic could not be fully removed by impurity removal treatment, and the final residue reached 0.21 mg / L. In Comparative Example 2, a combination of barium carbonate and sodium sulfide was used as a precipitant, wherein barium carbonate had poor solubility and could not be fully dissociated in the solution to produce enough Ba 2+ However, the arsenic was not effectively utilized, resulting in poor arsenic removal effect, and the final residue reached 0.35 mg / L; in Comparative Example 3, the arsenic could not be removed by simply adding sodium sulfide, and the lead removal effect of sodium sulfide was not better than that of Example 1; in Comparative Example 4, barium carbonate was a sparingly soluble substance with poor solubility. Adding an equal amount of barium carbonate alone would result in the inability to fully remove both lead and arsenic, and the final residue reached 0.38 mg / L. Lead could not be fully removed either, and the residue reached 3.50 mg / L.

[0136] The present invention illustrates the detailed features of the present invention through the above embodiments, but the present invention is not limited to the above detailed features, that is, it does not mean that the present invention must rely on the above detailed features to be implemented. Those skilled in the art should understand that any improvement to the present invention, equivalent replacement of the technical features selected by the present invention, addition of auxiliary technical features, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for simultaneously removing lead and arsenic from a nickel-lead-arsenic solution, characterized in that: The method comprises the following steps: The nickel-lead-arsenic solution is subjected to oxidation treatment to obtain an oxidized material; The oxidized material is treated with barium sulfide to remove impurities to obtain a purified material.

2. The method according to claim 1, characterized in that The nickel content in the nickel-lead-arsenic solution is 60-80 g / L; And / or, the lead content in the nickel-lead-arsenic solution is 5 to 20 mg / L; And / or, the arsenic content in the nickel-lead-arsenic solution is 0.1-2 mg / L.

3. The method according to claim 1, characterized in that The anions in the nickel-lead-arsenic containing solution include sulfate.

4. The method according to claim 1, characterized in that: The nickel-lead-arsenic-containing solution also includes a third metal element; Wherein, the third metal element includes any one of cobalt, iron or copper, or a combination of at least two of them.

5. The method according to claim 1, characterized in that The nickel-lead-arsenic containing solution is an electrolytic nickel anolyte; And / or, the pH of the nickel-lead-arsenic containing solution is 1.0-2.

0.

6. The method according to claim 1, characterized in that The temperature of the oxidation treatment is 30-80°C.

7. The method according to any one of claims 1 to 6, characterized in that: The oxidation treatment comprises: treating the nickel-lead-arsenic containing solution with an oxidant; Wherein, the oxidant includes any one of oxygen, hydrogen peroxide or sodium persulfate, or a combination of at least two thereof.

8. The method according to claim 7, characterized in that The molar amount of the oxidant is 2 to 5 times the molar amount of arsenic in the nickel-lead-arsenic solution.

9. The method according to any one of claims 1 to 6, characterized in that: The ratio of the molar amount of the barium sulfide to the total molar amount of lead and arsenic in the oxidized material is 5 to 10:

1.

10. The method according to any one of claims 1 to 6, characterized in that: The pH of the impurity removal treatment is 3.0 to 5.0; And / or, the temperature of the impurity removal treatment is 30-60°C.

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