CN110004292A - A process for purifying waste manganese sulfate solution to reduce calcium and magnesium content - Google Patents

Abstract

The invention discloses a process for purifying waste manganese sulfate solution to reduce calcium and magnesium content, comprising the following steps: S1, taking manganese sulfate waste liquid containing calcium and magnesium, heating the waste liquid to 30-40° C., and adding oxalic acid , a mixed solution of sodium oxalate and ammonium oxalate, and the reaction is stirred at a constant temperature for 2 to 4 hours; S2, after the solution reacted in step S1 is allowed to stand, a purified manganese sulfate solution is obtained after removing the precipitation; wherein, the oxalic acid in the mixed solution , the mass ratio of sodium oxalate and ammonium oxalate is (2～3):1:1. The scheme of the present invention uses oxalic acid and oxalate solution to remove impurities from manganese sulfate. The method technically avoids the impact on the environment of traditional technology using fluoride to remove impurities, and the manganese sulfate produced in the process of hydrometallurgy is purified and reused. At the same time, it can also achieve non-toxic or low-toxicity.

Description

A process for purifying waste manganese sulfate solution to reduce calcium and magnesium content

technical field

The invention relates to the technical field of environmental protection, in particular to a process for purifying waste manganese sulfate solution to reduce calcium and magnesium content.

Background technique

Hydrometallurgy is the process of contacting ores, concentrates or other raw materials enriched by beneficiation with aqueous solutions or other liquids, through chemical reactions, etc., to transfer the useful metals contained in the raw materials into the liquid phase, and then to the liquid phase. The various useful metals contained are separated and enriched, and finally recovered in the form of metal compounds. Copper and cobalt are two commonly used chemical raw materials, and they are usually extracted by hydrometallurgy. In the traditional hydrometallurgy process, after copper, cobalt and other metals are extracted, a large amount of manganese sulfate solution containing calcium and magnesium impurities will be left. If these industrial wastewater is directly discharged, it will cause heavy metal harm to water flow and soil, and cause waste of metal resources. At the same time, as an important trace element fertilizer, manganese sulfate can make crops grow well, and it is also an important feed additive. When it is added to the feed, it has a fattening effect and can make livestock and poultry develop well. In addition, manganese sulfate can also be widely used in medicine, paint drier, ceramics, printing and dyeing, the production of electrolytic manganese and the manufacture of other manganese salts. Therefore, no matter from the perspective of environmental protection or resource recovery, it is necessary to recycle manganese sulfate wastewater.

At present, there are three main methods for reducing Ca and Mg ions in manganese sulfate waste liquid: inorganic salt chemical precipitation method, extraction method and concentration and standing method. According to literature reports, the chemical precipitation method of inorganic salts is the main method to reduce Ca and Mg ions, but the inorganic salt precipitation method in the prior art usually introduces new impurity ions and the quality of manganese sulfate in the recycling of metallurgical waste liquid is also affected. Higher requirements are put forward, especially the requirements for the content of impurities in manganese sulfate are quite harsh. In the prior art, most researchers use fluoride to remove impurities from Ca and Mg ions, but the toxicity of fluoride is harmful to the human body and the environment. The method of calcium and magnesium ions in liquid is of great significance.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide an economical and environmentally friendly process for purifying waste manganese sulfate solution to reduce calcium and magnesium content.

In order to solve the above-mentioned technical problems, the technical scheme adopted in the present invention is: a process for purifying waste manganese sulfate solution to reduce calcium and magnesium content, comprising the following steps:

S1, take the manganese sulfate waste liquid containing calcium and magnesium, after the waste liquid is heated to 30～40 ℃, add the mixed solution of oxalic acid, sodium oxalate and ammonium oxalate, and stir the reaction under constant temperature for 2～4h;

S2, after the solution reacted in step S1 is allowed to stand, remove the precipitation to obtain a purified manganese sulfate solution;

Wherein, the mass ratio of oxalic acid, sodium oxalate and ammonium oxalate in the mixed solution is (2-3):1:1.

Preferably, the mass ratio of oxalic acid, sodium oxalate and ammonium oxalate in the mixed solution is 2:1:1.

Further, in the step S1, the temperature raising operation is to place the container containing the waste liquid in an environment that has been heated to 60-80°C.

Further, in the step S1, the stirring speed is 5-15 rad/s; preferably, the stirring speed is 10 rad/s.

Further, in the step S2, the time of the standing operation is 24-48 hours.

Further, in the step S2, the operation of removing the precipitation is to remove the precipitation of magnesium oxalate and calcium oxalate through a filtering operation.

Further, in the step S1, the manganese sulfate waste liquid containing calcium and magnesium is a hydrometallurgical waste liquid.

Further, in the step S1, the waste liquid is manganese sulfate waste liquid remaining after extraction of copper and/or cobalt.

Further, the standing operation is performed at room temperature, and the room temperature is 15-35°C, preferably 20-25°C.

The beneficial effects of the present invention are: the solution of the present invention utilizes oxalic acid and oxalate mixed solution to remove Ca and Mg in manganese sulfate waste liquid, and combines inorganic salt chemical precipitation method with traditional metallurgical industry, which is economical and environmentally friendly. With the rapid development of electronic chemicals in China in recent years, manganese _sulfate , as the main raw material for the production of these electronic chemicals, has attracted more and more attention. Effective recycling and reuse, the scheme of the present invention can not only effectively improve the utilization rate of limited metal resources, but also effectively reduce the environmental pollution during the experiment process by recycling the waste; the scheme of the present invention uses a chemical reaction method, Utilizing the characteristics of oxalic acid and calcium and magnesium elements to generate oxalate to remove impurities from industrial manganese sulfate waste liquid, the method is simple and easy to implement, greatly shortens the process of recycling industrial waste in the prior art, and can effectively obtain magnesium oxalate mixed calcium oxalate White powder, at the same time, the removal rate of calcium and magnesium in the solution treated by the solution of the present invention can reach more than 65% and 62%, and the solution treated by the solution of the present invention can be used for manganese sulfate recycling; the solution of the present invention can directly The waste liquid obtained after traditional hydrometallurgy is purified, which greatly shortens the process of waste recycling.

Detailed ways

In order to describe in detail the technical content, achieved objects and effects of the present invention, the following descriptions are given in conjunction with the embodiments.

An embodiment of the present invention is: a process for purifying waste manganese sulfate solution to reduce calcium and magnesium content, comprising the following steps:

S1, take the _MnSO waste liquid remaining after extracting metals such as copper and cobalt, pour the waste liquid into a beaker, put it into a beaker that has been heated to 60-80 ° C (to better ensure that the temperature inside the solution reaches a uniform temperature) 30 ~ 40 degrees) in the DF-101 series collector type constant temperature heating magnetic stirrer, after the solution temperature reaches 30 ~ 40 ℃, add the mixed solution of oxalic acid, sodium oxalate and ammonium oxalate, the DF-101 series collector heat The stirring speed of the constant temperature heating magnetic stirrer was adjusted to 10rad/s, the time was recorded, and the reaction was stirred at a constant temperature for 3h;

S2. The beaker after the reaction was left standing at room temperature for 36h, and after sampling, 12.5cm qualitative filter paper and a funnel were used to filter to obtain white precipitates of magnesium oxalate and calcium oxalate; the filtrate was collected to obtain a purified manganese sulfate solution.

For the same source of MnSO4 waste liquid, the mixed solution containing oxalic acid, sodium oxalate and _ammonium oxalate with different mass ratios was used to remove calcium and magnesium. coupled plasma mass spectrometry, ICP-MS) test, and calculate the calcium and magnesium removal rates as shown in Table 1 below:

Table 1 Removal ratio of calcium and magnesium by mixed solutions of oxalic acid, sodium oxalate and ammonium oxalate with different mass ratios

As can be seen from the above table, the mixed solution of oxalic acid, sodium oxalate and ammonium oxalate with a mass ratio of (2～3):1:1 can surprisingly purify calcium and magnesium in the waste liquid more effectively, and purify with this mixed solution During treatment, the purification rate of calcium ions can reach more than 65.89%, and the removal rate of magnesium can reach more than 62.27%; and the solution treated by the solution of the present invention has suitable pH and can be directly used in the manganese sulfate recycling process.

In order to observe the reaction situation of manganese sulfate, calcium sulfate and magnesium sulfate and oxalic acid, respectively take manganese sulfate, calcium sulfate and magnesium sulfate to carry out blank control experiment; get 10g sulfate (manganese sulfate, calcium sulfate or magnesium sulfate) sample and put it into a beaker Then, dissolve in 100ml tap water to make a solution, add 15g oxalic acid, stir with a glass rod and observe the reaction status in the solution, the specific phenomenon is shown in Table 2 below:

Table 2 Reaction phenomenon of different sulfates and oxalic acid

At the same time, a control experiment was carried out on different types of oxalates, and it was found that the potassium oxalate solution and the manganese precipitated violently and could not replace the calcium and magnesium precipitates, while other oxalates would make the cost too high.

To sum up, the solution of the present invention is especially suitable for reducing calcium and magnesium content elements in the MnSO ₄ solution remaining after extracting metals such as copper and cobalt in the traditional hydrometallurgical process. The solution of the present invention adopts oxalic acid, sodium oxalate and ammonium oxalate. Mixing in a specific proportion can achieve the effect of efficiently reducing the content of calcium and magnesium, and the cost of oxalic acid, sodium oxalate and ammonium oxalate is low, and it is a waste liquid treatment method with high economic benefits, environmental protection and low toxicity. A method of combining metallurgy and ionic waste liquid treatment, which greatly shortens the process of waste recycling; the scheme of the present invention uses oxalic acid solution to remove impurities from manganese sulfate, avoiding the traditional method of using fluoride to remove impurities. The damage caused by the environment, the manganese sulfate produced in the process of hydrometallurgy can be purified and reused, and it can also achieve non-toxic or low-toxicity.

The above are only the embodiments of the present invention, and are not intended to limit the scope of the patent of the present invention. All equivalent transformations made by using the contents of the description of the present invention, or directly or indirectly applied in the relevant technical fields, are similarly included in the scope of the present invention. within the scope of patent protection.

Claims (10)

1. a kind of technique that the purification of waste sulfate manganese solution reduces calcium-magnesium content, it is characterised in that: the following steps are included:

S1, take the manganese sulfate waste liquid containing calcium and magnesium, after the waste liquid is warming up to 30~40 DEG C, be added oxalic acid, sodium oxalate and Ammonium oxalate mixed solution is stirred to react 2~4h under constant temperature；

S2, by through step S1 reaction after solution left standstill after, removal precipitating after be purified after manganese sulfate solution；

Wherein, the mass ratio of the mixed solution mesoxalic acid, sodium oxalate and ammonium oxalate is (2~3): 1:1.

2. the technique that waste sulfate manganese solution purification according to claim 1 reduces calcium-magnesium content, it is characterised in that: described The mass ratio of mixed solution mesoxalic acid, sodium oxalate and ammonium oxalate is 2:1:1.

3. the technique that waste sulfate manganese solution purification according to claim 1 reduces calcium-magnesium content, it is characterised in that: described In step S1, the warming temperature is to be placed in the container for being contained with waste liquid to have warmed up into 60~80 DEG C of environment.

4. the technique that waste sulfate manganese solution purification according to claim 1 reduces calcium-magnesium content, it is characterised in that: described In step S1, mixing speed is 5~15rad/s.

5. the technique that waste sulfate manganese solution purification according to claim 4 reduces calcium-magnesium content, it is characterised in that: described Mixing speed is 10rad/s.

6. the technique that waste sulfate manganese solution purification according to claim 1 reduces calcium-magnesium content, it is characterised in that: described In step S2, the time for standing operation is 24~48h.

7. the technique that waste sulfate manganese solution purification according to claim 1 reduces calcium-magnesium content, it is characterised in that: described In step S2, the operation of the removal precipitating is to remove magnesium oxalate and calcium oxalate precipitation by filter operation.

8. waste sulfate manganese solution purification according to claim 1-7 reduces the technique of calcium-magnesium content, feature Be: in the step S1, the manganese sulfate waste liquid containing calcium and magnesium is hydrometallurgy waste liquid.

9. the technique that waste sulfate manganese solution purification according to claim 8 reduces calcium-magnesium content, it is characterised in that: described In step S1, the waste liquid is to extract remaining manganese sulfate waste liquid after copper and/or cobalt.

10. waste sulfate manganese solution purification according to claim 1-7 reduces the technique of calcium-magnesium content, feature Be: the standing operation is to carry out at room temperature, and the room temperature is 15~35 DEG C, preferably 20~25 DEG C.