A combined detection method for ferromanganese content in ferromanganese ore

Abstract

The present invention provides a combined detection method for the content of manganese and iron in ferromanganese ore, the combined detection method comprising the following steps: adding an ferromanganese ore sample to an acid solution for dissolution, oxidizing Mn and Fe in the solution to high valence states of Mn and Fe respectively, and using a pretreated ion exchange column to sequentially perform enrichment adsorption and elution to achieve Mn and Fe content. 4+ with Fe 3+ The collected eluate was fixed to volume, and a portion of the fixed volume was measured by ion chromatography to measure Fe 3+ content, and the remaining fixed volume solution is added with precipitation alkali solution for precipitation to obtain a mixture of MnO(OH)2 and Fe(OH)3. Then, the manganese content and iron content in the ferromanganese ore can be obtained respectively according to simple calculations, thereby realizing the combined detection of manganese and iron contents in the ferromanganese ore. It has the advantages of good stability, accuracy, effectiveness, low cost, etc., and is convenient for large-scale promotion and use.

Description

Technical Field

[0001] The invention relates to the field of lithium ion battery positive electrode materials, and in particular to a combined detection method for ferromanganese content in ferromanganese ore. Background Art

[0002] With the development of the lithium-ion battery industry, the market for lithium iron manganese phosphate, a new type of phosphate lithium battery positive electrode material, is becoming increasingly hot, making the lithium-ion battery industry's requirements for ferromanganese raw materials increasingly high. As a common ferromanganese raw material, ferromanganese ore needs to be accurately input and key points of the chemical process need to be controlled in the actual production process. Therefore, it is necessary to analyze and test the manganese and iron contents in ferromanganese ore separately.

[0003] At present, the existing detection methods for the manganese-iron content in ferromanganese ore are mainly divided into titration method and precision instrument method, and most of them detect manganese and iron separately.

[0004] Titration is mainly to digest the iron manganese ore with acid, then oxidize it into high-valent ions, and then use ammonium ferrous sulfate reducing agent to titrate the capacity of high-valent manganese ions, while the iron content is mainly EDTA complexation and stannous chloride reduction. For example, CN102749329A discloses a detection method for elemental manganese in lithium manganese phosphate, by using a hot solution containing a buffer solution to dissolve elemental manganese, to achieve the separation of lithium manganese phosphate and elemental manganese, the filtrate obtained after dissolution is first added with phosphoric acid, mixed, heated, the solution evaporates until phosphoric acid smoke just emerges, stops heating, then adds ammonium nitrate, shakes, stands, removes nitrogen oxides, cools, adds deionized water, shakes, continues to cool to room temperature, and then titrates with ammonium ferrous sulfate standard titration solution until the solution is light red; then add N-phenylated anthranilic acid, continue to titrate to the titration end point, and record the volume of ammonium ferrous sulfate standard solution consumed during titration, so as to accurately detect the content of elemental manganese in lithium manganese phosphate. For example, CN113418910A discloses a method for determining the content of iron ions, wherein a sample solution containing a sample of mass m is taken, the pH is adjusted to 1-3, heated to 60-80°C, and titrated to the end point of the reaction with an EDTA solution of molar concentration C1 in the presence of an indicator, the volume of the EDTA solution consumed is V1, the molar mass of iron is defined as M, and the calculation formula for the content of iron ions is: Fe%=C1V1M / m×100%. However, the reaction time of the titration method is relatively long, the degree of reaction cannot be controlled, and the end point of the titration reaction needs to be judged by the naked eye, which has a large deviation.

[0005] The precision instrument method mainly includes ICP test method and XRF test method. Such methods have a common point that the cost is high, and the maintenance and operation cost of precision instruments is high. The results of ICP are greatly affected by other elements, and the test results of samples with low content have large deviations; XRF results are relatively accurate, but require professional personnel to operate, and require high temperature and high pressure conditions for detection. The overall risk of the experiment is relatively large, and it is impossible to achieve flow operation. In addition, the prior art also discloses some joint detection methods that can simultaneously detect the content of multiple elements such as manganese and iron using precision instruments. For example, CN102914532A discloses a method for determining the content of titanium, manganese, iron, nickel, and tungsten in tantalum-cobalt-based alloys, based on an inductively coupled plasma atomic emission spectrometer, and the joint detection method includes weighing a sample, preparing a sample solution, preparing a series of calibration solutions, drawing a working curve, respectively determining the concentrations of titanium, manganese, iron, nickel, and tungsten in the sample solution, calculating the measurement results and obtaining the contents of titanium, manganese, iron, nickel, and tungsten respectively. However, the current joint detection method still relies on ICP test methods and XRF test methods, and still cannot overcome the problems of high cost and harsh operating conditions.

[0006] In summary, there is a need to develop a combined detection method for the manganese and iron content in ferromanganese ore, which has the advantages of good stability, accuracy, effectiveness and low cost. Summary of the invention

[0007] In view of the problems existing in the prior art, the present invention provides a combined detection method for the content of manganese iron in ferromanganese ore, the combined detection method comprising the following steps: adding an ferromanganese ore sample to an acid solution for dissolution, oxidizing Mn and Fe in the solution to Mn 4+ with Fe 3+ The high-valent state of Mn is enriched, adsorbed and eluted in sequence using a pretreated ion exchange column to achieve 4+ with Fe 3+ The collected eluate was fixed to volume, and a portion of the fixed volume was measured by ion chromatography to measure Fe 3+ content, and the remaining fixed volume solution is added with precipitation alkali solution for precipitation to obtain a mixture of MnO(OH)2 and Fe(OH)3. Then, the manganese content and iron content in the ferromanganese ore can be obtained respectively according to simple calculations, thereby realizing the combined detection of manganese and iron contents in the ferromanganese ore. It has the advantages of good stability, accuracy, effectiveness, low cost, etc., and is convenient for large-scale promotion and use.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] The object of the present invention is to provide a combined detection method for ferromanganese content in ferromanganese ore, the combined detection method comprising the following steps:

[0010] Sample dissolution: Weigh the iron-manganese ore sample with a mass of m1, add acid solution to dissolve it, and obtain the dissolved solution after the first solid-liquid separation;

[0011] Oxidation reaction: Add an oxidant to the solution to oxidize it to obtain 4+ with Fe 3+ of oxidizing liquid;

[0012] Column enrichment: The oxidized liquid is passed through a pretreated ion exchange column for enrichment and adsorption, and washed with water until the filtrate is colorless, the filtrate is discarded, and then eluted with a desorption acid solution, and the eluate is collected;

[0013] Precipitation detection: The eluate is fixed to volume to obtain a fixed volume solution with a volume of V0; the fixed volume solution with a volume of V1 is measured, and the Fe content in the fixed volume solution is measured by ion chromatography. 3+ The content is a; add precipitation alkali solution to the remaining fixed volume solution for precipitation, and sequentially undergo a second solid-liquid separation, washing, drying and weighing to obtain a manganese-iron mixed solid with a mass of m2; the manganese-iron mixed solid is a mixture of MnO(OH)2 and Fe(OH)3; the manganese content Mn% and the iron content Fe% are calculated according to the following formulas:

[0014]

[0015]

[0016] Where:

[0017] M S1 is the relative molecular mass of MnO(OH)2;

[0018] M Mn is the relative atomic mass of Mn;

[0019] M S2 is the relative molecular mass of Fe(OH)3;

[0020] M Fe is the relative atomic mass of Fe;

[0021] m1 is the mass of the ferromanganese ore sample, in mg;

[0022] m2 is the mass of the ferromanganese mixed solid, in mg;

[0023] V0 is the volume of the constant solution obtained after the eluent is constant to volume, in mL;

[0024] V1 is the volume of the constant volume solution used for ion chromatography measurement, in mL;

[0025] a is Fe in the constant volume solution 3+Content, unit: mg / mL.

[0026] The combined detection method of the present invention firstly oxidizes Mn and Fe in the iron-manganese ore to Mn by sample dissolution and oxidation reaction. 4+ with Fe 3+ The high-valence state of Mn is then enriched, adsorbed and eluted in turn through a pretreated ion exchange column to achieve 4 + with Fe 3+ After enrichment, precipitating alkali solution is added for precipitation to obtain a mixture of MnO(OH)2 and Fe(OH)3. Then, the manganese content and iron content in the ferromanganese ore can be obtained respectively according to simple calculations, thus realizing the joint detection of manganese and iron contents in the ferromanganese ore. It has the advantages of good stability, accuracy, effectiveness, low cost, etc., and is convenient for large-scale promotion and use.

[0027] It is worth mentioning that the ferromanganese ore sample is a commonly used ore raw material in the field of lithium batteries and will not be described in detail here.

[0028] As a preferred technical solution of the present invention, the acid solution includes a mixed acid solution composed of any two of nitric acid, hydrochloric acid, sulfuric acid and phosphoric acid, such as a mixed acid solution of nitric acid and hydrochloric acid, a mixed acid solution of sulfuric acid and phosphoric acid, a mixed acid solution of sulfuric acid and nitric acid, a mixed acid solution of sulfuric acid and hydrochloric acid, or a mixed acid solution of hydrochloric acid and phosphoric acid; however, after multiple experiments and verification by the inventor, compared with the mixed acid solution of nitric acid and hydrochloric acid, the dissolution effect of other mixed acid solutions is slightly worse, and occasionally there is a small amount of manganese in the iron manganese ore sample that is incompletely dissolved, resulting in a low manganese content finally detected.

[0029] Preferably, the acid solution is a mixed acid solution of nitric acid and hydrochloric acid in a volume ratio of 1:1.

[0030] Preferably, the mass concentration of the nitric acid is 33-35%, such as 33%, 33.5%, 34%, 34.5% or 35%, etc., but is not limited to the listed values, and other values ​​not listed within the above numerical range are also applicable.

[0031] Preferably, the mass concentration of the hydrochloric acid is 18-19%, for example 18%, 18.1%, 18.3%, 18.5%, 18.7%, 18.8% or 19%, etc., but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0032] Preferably, the molar concentration of sulfuric acid is 0.75-1.25 mol / L, for example 0.75 mol / L, 0.85 mol / L, 0.95 mol / L, 1.00 mol / L, 1.05 mol / L, 1.10 mol / L, 1.15 mol / L or 1.25 mol / L, etc., but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0033] Preferably, the molar concentration of the phosphoric acid is 0.75-1.25 mol / L, for example 0.75 mol / L, 0.85 mol / L, 0.95 mol / L, 1.00 mol / L, 1.05 mol / L, 1.10 mol / L, 1.15 mol / L or 1.25 mol / L, etc., but is not limited to the listed values, and other values ​​not listed within the above numerical range are also applicable.

[0034] Preferably, the ratio of the mass of the ferromanganese ore sample to the volume of the acid solution is 1g:(200-600)mL, for example 1g:200mL, 1g:300mL, 1g:400mL, 1g:500mL or 1g:600mL, etc., but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable; generally, a little more acid solution is added, which can ensure that manganese and iron in the ferromanganese ore sample can be completely dissolved on the one hand, and can also prevent the influence of acid volatilization on the dissolution effect at a dissolution temperature of 100-200°C.

[0035] Preferably, the dissolution temperature is 100-200°C, for example 100°C, 110°C, 130°C, 150°C, 160°C, 180°C or 200°C, etc., but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0036] It is worth noting that the dissolution temperature of 100-200°C means that the temperature rises slowly during the dissolution process, which is a process of slow acid volatilization while dissolving, and will not affect the complete dissolution of manganese and iron in the manganese ore sample.

[0037] As a preferred technical solution of the present invention, the oxidant includes hydrogen peroxide solution and / or ozone.

[0038] It is worth noting that the oxidant of the present invention is preferably hydrogen peroxide solution and / or ozone, which has the advantages of mild oxidation conditions and no pollution, and will not interfere with the subsequent joint detection of manganese and iron content.

[0039] Preferably, the mass concentration of the hydrogen peroxide solution is 5-35%, for example 5%, 10%, 15%, 20%, 25%, 30% or 35%, etc., but is not limited to the listed values, and other values ​​not listed within the above numerical range are also applicable.

[0040] Preferably, during the oxidation reaction, the hydrogen peroxide solution is gradually added for oxidation until the ultraviolet absorbance of the obtained reaction solution at 505 nm no longer changes.

[0041] It is worth noting that hydrogen peroxide solution has strong oxidizing ability and is green and environmentally friendly. It can be decomposed into water and oxygen after heating, which is environmentally friendly and a very cost-effective oxidant. 4+ with Fe 3+ There is ultraviolet absorption at 505nm, so the Mn in the solution can be detected by monitoring the change of ultraviolet absorbance at 505nm. 4+ with Fe 3+ The judgment of whether the oxidation is complete can effectively monitor the end point of the oxidation reaction and avoid the problem of oxidation not reaching the end point or exceeding the oxidation end point. Compared with judging the oxidation end point by the color of the solution, the method of monitoring the change of ultraviolet absorbance at 505nm is more obvious and intuitive, avoiding the problem of more interference in color change.

[0042] As a preferred technical solution of the present invention, after the oxidation reaction and before the column enrichment, the oxidation liquid is heated to remove acid.

[0043] Preferably, the temperature of the heating deacidification treatment is 100-200°C, for example 100°C, 110°C, 130°C, 150°C, 160°C, 180°C or 200°C, but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0044] Preferably, the heating deacidification treatment time is 10-60 min, for example 10 min, 20 min, 30 min, 40 min, 50 min or 60 min, etc., but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0045] It is worth noting that, in the sample dissolution of the present invention, the acid solution is a mixed acid solution of nitric acid and hydrochloric acid in a volume ratio of 1:1, which not only has excellent dissolution performance and can selectively dissolve Mn and Fe in the ferromanganese ore sample, but also after the oxidation is completed, the nitric acid and hydrochloric acid can be directly volatilized by heating and deacidification treatment, without introducing other oxidizing or reducing acids, thereby reducing the error of combined detection.

[0046] As a preferred technical solution of the present invention, the ion exchange column is filled with manganese ion exchange resin and iron ion exchange resin.

[0047] Preferably, the manganese ion exchange resin is Amberlite cation exchange resin, and its model includes any one of CH-90, FEROX, D113, SJ-004, T-52H or KATALOX LIGHT.

[0048] Preferably, the iron ion exchange resin is Amberlite cation exchange resin, and the model includes any one of IR-120, T-IRR, A-21S, KP-759, TP207 or D401.

[0049] Preferably, the mass ratio of the manganese ion exchange resin to the iron ion exchange resin is (1-3):(1-3), for example, 1:1, 1:2, 1:3, 2:1, 2:3, 3:1 or 3:2, etc., but is not limited to the listed values, and other values ​​not listed within the above numerical range are also applicable.

[0050] Preferably, the total volume of the manganese ion exchange resin and the iron ion exchange resin is more than 3 times the volume of the oxidizing solution.

[0051] Preferably, the flow rate of the enrichment adsorption is 1-1.5 mL / min, for example, 1 mL / min, 1.1 mL / min, 1.2 mL / min, 1.3 mL / min, 1.4 mL / min or 1.5 mL / min, but is not limited to the listed values, and other values ​​not listed within the above numerical range are also applicable.

[0052] Preferably, the pretreatment comprises mixing the manganese ion exchange resin and the iron ion exchange resin and then wet loading the mixture onto a column, and washing the ion exchange column with water until the pH value of the washing solution is neutral and odorless.

[0053] It is worth noting that the ion exchange column of the present invention is firstly activated by activating the manganese ion exchange resin and the iron ion exchange resin respectively, and then loaded onto the column by a wet column loading method, which will not be described in detail here.

[0054] It is worth noting that the combined detection method of the present invention uses an ion exchange column filled with manganese ion exchange resin and iron ion exchange resin for column enrichment. The manganese ion exchange resin and iron ion exchange resin used have good specificity and can quickly and efficiently enrich Mn 4+ with Fe 3+ , while also effectively ensuring that Mn 4+ with Fe 3+ The high prices will not be restored.

[0055] As a preferred technical solution of the present invention, the desorption acid solution includes any one of hydrochloric acid, sulfuric acid or nitric acid or a combination of at least two thereof. However, when hydrochloric acid is used as the desorption acid solution, the elution effect is the best, which can not only realize the recovery of the ion exchange resin, but also has the advantages of safer desorption products and consistent concentration.

[0056] Preferably, the desorption acid solution is hydrochloric acid with a mass concentration of 18-19%.

[0057] Preferably, the completion standard of the elution is: firstly elute with the desorption acid solution until the ion exchange column presents the original color, and then elute with the desorption acid solution whose volume is 1-2 times of the column volume of the ion exchange column.

[0058] It is worth noting that there is a clear color difference between manganese ion exchange resin and iron ion exchange resin before and after adsorption. For example, before adsorption, Amberlite cation exchange resin CH-90 as manganese ion exchange resin and Amberlite cation exchange resin IR-120 as iron ion exchange resin present a mixture of yellow and brown, while after adsorption, the resin presents a brown color as a whole. Therefore, desorption acid is first used to elute until the manganese ion exchange resin and the iron ion exchange resin present their original colors to ensure that most of the Mn 4+ with Fe 3+ The Mn 4+ with Fe 3+ The combined detection method of the present invention is thus ensured to be accurate.

[0059] As a preferred technical solution of the present invention, after the elution and before the constant volume, the eluent is heated and concentrated; the heating and concentration helps to remove Mn 4+ with Fe 3+ The concentration is adjusted to a reasonable range, which is helpful for subsequent ion chromatography detection and precipitation reaction to be fully carried out. The specific concentration ratio can be reasonably selected by those skilled in the art according to actual conditions.

[0060] As a preferred technical solution of the present invention, the precipitation alkali solution includes a sodium hydroxide solution with a concentration of 0.08-0.12 mol / L, such as 0.08 mol / L, 0.09 mol / L, 0.1 mol / L, 0.1 mol / L, 0.11 mol / L or 0.12 mol / L, etc., but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0061] It is worth noting that if alkaline ammonia water is used as the precipitation alkali solution, there will be disadvantages such as ammonia volatilization and a strong pungent odor; if potassium hydroxide solution is used as the precipitation alkali solution, there will be disadvantages such as too strong alkalinity and no current general calibration method; for this reason, the precipitation alkali solution of the present invention uses commonly used sodium hydroxide solution, and there is a national standard method that can titrate to obtain the accurate content of sodium hydroxide.

[0062] Preferably, the volume ratio of the remaining total volumetric solution to the precipitation alkali solution is 1:(2-8), for example 1:2, 1:3, 1:4, 1:5, 1:6, 1:7 or 1:8, etc., but is not limited to the listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0063] It is worth noting that the combined detection method of the present invention adopts a precipitation method to obtain a mixture of MnO(OH)2 and Fe(OH)3, which has the advantages of simple operation and simple calculation; moreover, the volume ratio of the remaining total volume solution to the sodium hydroxide solution is 1:(2-8), which can ensure that the Mn in the eluent is 4+ with Fe 3+ Can settle completely.

[0064] As a preferred technical solution of the present invention, the second solid-liquid separation is performed by filtering using a glass sand core crucible.

[0065] Preferably, the completion standard of the washing is: washing with water until the pH value of the obtained washing liquid is neutral.

[0066] As a preferred technical solution of the present invention, the joint detection method comprises the following steps:

[0067] Sample dissolution: weighing a ferromanganese ore sample with a mass of m1, adding acid solution to dissolve it at 100-200°C, and obtaining a dissolved solution through a first solid-liquid separation; wherein the acid solution is a mixed acid solution of nitric acid and hydrochloric acid in a volume ratio of 1:1, and the mass concentration of the nitric acid is 33-35%, and the mass concentration of the hydrochloric acid is 18-19%; the ratio of the mass of the ferromanganese ore sample to the volume of the acid solution is 1g:(200-600)mL;

[0068] Oxidation reaction: gradually add a hydrogen peroxide solution with a mass concentration of 5-35% to the dissolved solution for oxidation until the ultraviolet absorbance of the obtained reaction solution at 505nm no longer changes, and then heat the obtained oxidized solution at 100-200°C for 10-60min to remove acid, thereby obtaining a Mn-containing 4+ with Fe 3+ of oxidizing liquid;

[0069] Column enrichment: preparing an ion exchange column loaded with manganese ion exchange resin and iron ion exchange resin, wherein the manganese ion exchange resin is Amberlite cation exchange resin, and its model includes any one of CH-90, FEROX, D113, SJ-004, T-52H or KATALOX LIGHT, and the iron ion exchange resin is Amberlite cation exchange resin, and its model includes any one of IR-120, T-IRR, A-21S, KP-759, TP207 or D401, and the mass ratio of the manganese ion exchange resin to the iron ion exchange resin is (1-3): (1-3), and the total volume of the manganese ion exchange resin and the iron ion exchange resin is more than 3 times the volume of the oxidation solution; mixing the manganese ion exchange resin and the iron ion exchange resin, and wet-loading the column, and washing the ion exchange column with water until the pH value of the washing solution is neutral and odorless, thereby obtaining a pretreated ion exchange column;

[0070] Passing the oxidized liquid through a pretreated ion exchange column for enrichment and adsorption at a flow rate of 1-1.5 mL / min, washing with water until the filtrate is colorless, discarding the filtrate, and then eluting with hydrochloric acid with a mass concentration of 18-19% until the manganese ion exchange resin and the iron ion exchange resin show their original colors, and then eluting with hydrochloric acid with a mass concentration of 18-19% that is 1-2 times the column volume of the ion exchange column, and collecting the eluate;

[0071] Precipitation detection: The eluate is first heated and concentrated and then fixed to volume to obtain a fixed volume solution with a volume of V0; the fixed volume solution with a volume of V1 is measured, and the Fe content in the fixed volume solution is measured by ion chromatography. 3+ The content is a; a sodium hydroxide solution with a concentration of 0.08-0.12 mol / L is added to the remaining total volume solution for precipitation, the volume ratio of the remaining total volume solution to the precipitation alkali solution is 1: (2-8), and a glass sand core crucible is used for filtration, and the filtered solid is washed with water until the pH value of the washing liquid is neutral, and then dried and weighed to obtain a manganese iron mixed solid with a mass of m2; the manganese iron mixed solid is a mixture of MnO (OH) 2 and Fe (OH) 3; the manganese content Mn% and the iron content Fe% are calculated according to the following formulas:

[0072]

[0073]

[0074] Where:

[0075] M S1 is the relative molecular mass of MnO(OH)2;

[0076] M Mn is the relative atomic mass of Mn;

[0077] M S2 is the relative molecular mass of Fe(OH)3;

[0078] M Fe is the relative atomic mass of Fe;

[0079] m1 is the mass of the ferromanganese ore sample, in mg;

[0080] m2 is the mass of the ferromanganese mixed solid, in mg;

[0081] V0 is the volume of the constant solution obtained after the eluent is constant to volume, in mL;

[0082] V1 is the volume of the constant volume solution used for ion chromatography measurement, in mL;

[0083] a is Fe in the constant volume solution 3+ Content, unit: mg / mL.

[0084] Compared with the prior art solutions, the present invention has at least the following beneficial effects:

[0085] (1) The combined detection method of the present invention firstly oxidizes Mn and Fe in the iron manganese ore to Mn by acid dissolution and oxidation. 4+ with Fe 3+ The high-valence state of Mn is then enriched, adsorbed and eluted in turn through a pretreated ion exchange column to achieve 4 + with Fe 3+ The mixture of MnO(OH)2 and Fe(OH)3 is obtained by adding precipitation alkali solution for precipitation, and then the manganese content and iron content in the ferromanganese ore can be obtained by simple calculation, thus realizing the joint detection of manganese and iron content in the ferromanganese ore, which has the advantages of good stability, accuracy, effectiveness and low cost.

[0086] (2) The combined detection method of the present invention uses manganese ion exchange resin and iron ion exchange resin with good specificity, which can not only achieve Mn 4+ with Fe 3+ The enrichment of ions ensures the accuracy of the test results and can also realize the recycling and reuse of manganese ion exchange resin and iron ion exchange resin, further reducing the test cost.

[0087] (3) The combined detection method of the present invention uses hydrogen peroxide solution as an oxidant, which can effectively oxidize all Mn and Fe in the solution into high-valent ions Mn 4+ with Fe 3+, and in the subsequent experimental process, it can be self-oxidized into water and oxygen, which is environmentally friendly and low-cost; at the same time, the introduction of an ultraviolet spectrophotometer to monitor the end point of the oxidation reaction can ensure that all Mn and Fe in the solution are oxidized to high-valent ions Mn 4+ with Fe 3+ , effectively saving experimental time;

[0088] (4) The combined detection method of the present invention uses sodium hydroxide solution for neutralization and precipitation. On the one hand, it can make the precipitation complete and obtain a mixture of MnO(OH)2 and Fe(OH)3 without being interfered by other factors. On the other hand, it can make the filtrate after precipitation contain only Na + and Cl - The filtrate obtained after sedimentation does not need to be specially treated, which is environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0089] Figure 1 The present invention is a schematic flow chart of a combined detection method for ferromanganese content in ferromanganese ore. DETAILED DESCRIPTION

[0090] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0091] To better illustrate the present invention and facilitate understanding of the technical solution of the present invention, typical but non-limiting embodiments of the present invention are as follows:

[0092] The combined detection method of the present invention comprises the following steps, and the corresponding flow chart is as follows: Figure 1 As shown:

[0093] Sample dissolution: Weigh the iron-manganese ore sample with a mass of m1, add a mixed acid solution of nitric acid and hydrochloric acid in a volume ratio of 1:1 to dissolve it, and obtain a dissolved solution after the first solid-liquid separation;

[0094] Oxidation reaction: gradually adding hydrogen peroxide solution to the dissolving solution for oxidation until the ultraviolet absorbance of the obtained reaction solution at 505 nm no longer changes, and then heating and deacidification treatment are performed to obtain a solution containing Mn 4+ with Fe 3+ Oxidizing liquid;

[0095] Column enrichment: The oxidized liquid is enriched and adsorbed through a pretreated ion exchange column, and washed with water until the filtrate is colorless, the filtrate is discarded, and then eluted with desorption acid to collect the Mn 4+ with Fe 3+ of the eluent;

[0096] Precipitation detection: The eluate is fixed to volume to obtain a fixed volume solution with a volume of V0; the fixed volume solution with a volume of V1 is measured, and preferably V0 is much smaller than V1, and the Fe content in the fixed volume solution is measured by ion chromatography. 3+ The content is a; sodium hydroxide solution is added to the remaining fixed volume solution for precipitation, and a manganese-iron mixed solid with a mass of m2 is obtained after a second solid-liquid separation, washing, drying and weighing; the manganese-iron mixed solid is a mixture of MnO(OH)2 and Fe(OH)3; the manganese content Mn% and the iron content Fe% are calculated according to the following formulas:

[0097]

[0098]

[0099] Where:

[0100] M S1 is the relative molecular mass of MnO(OH)2;

[0101] M Mn is the relative atomic mass of Mn;

[0102] M S2 is the relative molecular mass of Fe(OH)3;

[0103] M Fe is the relative atomic mass of Fe;

[0104] m1 is the mass of the ferromanganese ore sample, in mg;

[0105] m2 is the mass of the ferromanganese mixed solid, in mg;

[0106] V0 is the volume of the constant solution obtained after the eluent is constant to volume, in mL;

[0107] V1 is the volume of the constant volume solution used for ion chromatography measurement, in mL;

[0108] a is Fe in the constant volume solution 3+ Content, unit: mg / mL.

[0109] Example 1

[0110] This embodiment provides a combined detection method for ferromanganese content in ferromanganese ore, the combined detection method comprising the following steps:

[0111] Sample dissolution: Weigh 0.5010 g (m1) of an iron-manganese ore sample, add acid to dissolve it at 200°C, and obtain a dissolved solution through a first solid-liquid separation; wherein the acid is a mixed acid solution of nitric acid and hydrochloric acid in a volume ratio of 1:1, and the nitric acid is prepared by using concentrated nitric acid and water in a volume ratio of 1+1, with a mass concentration of 33-35%, and the hydrochloric acid is prepared by using concentrated hydrochloric acid and water in a volume ratio of 1+1, with a mass concentration of 18-19%, and 100 mL of nitric acid and hydrochloric acid are measured to obtain a mixed acid solution;

[0112] Oxidation reaction: gradually add a hydrogen peroxide solution with a mass concentration of 25% to the dissolving solution for oxidation until the ultraviolet absorbance of the obtained reaction solution at 505nm no longer changes, and then heat the obtained oxidized solution at 200°C for 30 minutes to remove the acid, and obtain a Mn-containing 4+ with Fe 3+ Oxidizing liquid;

[0113] Column enrichment: prepare an ion exchange column loaded with manganese ion exchange resin and iron ion exchange resin, wherein the manganese ion exchange resin is Amberlite cation exchange resin CH-90, the iron ion exchange resin is Amberlite cation exchange resin IR-120, the mass ratio of the manganese ion exchange resin to the iron ion exchange resin is 1:1, and the total volume of the manganese ion exchange resin and the iron ion exchange resin is 3 times the volume of the oxidation solution; mix the manganese ion exchange resin and the iron ion exchange resin and wet-column them, wash the ion exchange column with water until the pH value of the washing solution is neutral and odorless, to obtain a pretreated ion exchange column;

[0114] Passing the oxidizing liquid through a pretreated ion exchange column for enrichment and adsorption at a flow rate of 1 mL / min, and washing with water until the filtrate is colorless, discarding the filtrate, and then eluting with hydrochloric acid with a mass concentration of 18-19% (prepared with concentrated hydrochloric acid and water in a 1+1 volume ratio) until the manganese ion exchange resin and the iron ion exchange resin show their original colors, and then eluting with hydrochloric acid with a mass concentration of 18-19% (prepared with concentrated hydrochloric acid and water in a 1+1 volume ratio) 1.5 times the column volume of the ion exchange column, and collecting the eluate;

[0115] Precipitation detection: The eluate was first heated and concentrated at 150°C and then fixed to volume to obtain 50 mL (V0) of fixed solution; 1 mL (V1) of the fixed solution was measured and the Fe content in the fixed solution was measured by ion chromatography. 3+The content is 0.605 mg / mL (a); 150 mL of 0.1 mol / L sodium hydroxide solution is added to the remaining fixed volume solution for precipitation, and filtered using a glass sand core crucible, and the filtered solid is washed with water until the pH value of the washing liquid is neutral, and then dried and weighed to obtain a manganese-iron mixed solid with a mass of 124.25 mg (m2); the manganese-iron mixed solid is a mixture of MnO (OH) 2 and Fe (OH) 3; the manganese content Mn% is 7.20%, and the iron content Fe% is 6.04% calculated according to the following formulas;

[0116]

[0117]

[0118] Where:

[0119] M S1 is the relative molecular mass of MnO(OH)2, which is 104.938;

[0120] M Mn is the relative atomic mass of Mn, which is 54.938;

[0121] M S2 is the relative molecular mass of Fe(OH)3, which is 106.87;

[0122] M Fe is the relative atomic mass of Fe, which is 55.845;

[0123] m1 is the mass of the ferromanganese ore sample, in mg;

[0124] m2 is the mass of the ferromanganese mixed solid, in mg;

[0125] V0 is the volume of the constant solution obtained after the eluent is constant to volume, in mL;

[0126] V1 is the volume of the constant volume solution used for ion chromatography measurement, in mL;

[0127] a is Fe in the constant volume solution 3+ Content, unit: mg / mL.

[0128] Verification Example

[0129] In this verification example, a total of 0.0500 g (m1) of mixed solids of manganese chloride and ferrous chloride with a purity of 99.99% was selected, wherein the mass ratio of manganese chloride to ferrous chloride was 1.2:1, that is, the theoretical content of manganese in the mixed solid was 2.382%, and the theoretical content of iron was 2.002%.

[0130] The mixed solid was tested according to the combined detection method described in Example 1. During the precipitation detection process, the Fe content in the fixed volume solution was measured by ion chromatography. 3+ The content is 0.204 mg / mL (a), and a manganese-iron mixed solid with a mass of 41.89 mg (m2) is obtained; according to the formula, the manganese content Mn% is calculated to be 2.43%, and the iron content Fe% is 2.04%.

[0131] From the comparison between the above-mentioned embodiment 1 and the verification example, it can be seen that the difference between the measurement result using the present method and the actual result is less than 0.05%, which indicates that the present method has a high accuracy.

[0132] Example 2

[0133] This embodiment provides a combined detection method for ferromanganese content in ferromanganese ore, the combined detection method comprising the following steps:

[0134] Sample dissolution: Weigh 0.5022 g (m1) of an iron-manganese ore sample, add acid to dissolve it at 150°C, and obtain a dissolved solution through a first solid-liquid separation; wherein the acid is a mixed acid solution of nitric acid and hydrochloric acid in a volume ratio of 1:1, and the nitric acid is prepared by using concentrated nitric acid and water in a volume ratio of 1+1, with a mass concentration of 33-35%, and the hydrochloric acid is prepared by using concentrated hydrochloric acid and water in a volume ratio of 1+1, with a mass concentration of 18-19%, and 150 mL of nitric acid and hydrochloric acid are measured to obtain a mixed acid solution;

[0135] Oxidation reaction: gradually add a hydrogen peroxide solution with a mass concentration of 20% to the dissolving solution for oxidation until the ultraviolet absorbance of the obtained reaction solution at 505nm no longer changes, and then heat the obtained oxidized solution at 200°C for 30 minutes to remove the acid, and obtain a Mn-containing 4+ with Fe 3+ Oxidizing liquid;

[0136] Column enrichment: prepare an ion exchange column loaded with manganese ion exchange resin and iron ion exchange resin, wherein the manganese ion exchange resin is Amberlite cation exchange resin CH-90, the iron ion exchange resin is Amberlite cation exchange resin IR-120, the mass ratio of the manganese ion exchange resin to the iron ion exchange resin is 1:2, and the total volume of the manganese ion exchange resin and the iron ion exchange resin is 3 times the volume of the oxidation solution; mix the manganese ion exchange resin and the iron ion exchange resin and wet-column them, wash the ion exchange column with water until the pH value of the washing solution is neutral and odorless, and obtain a pretreated ion exchange column;

[0137] Passing the oxidizing liquid through a pretreated ion exchange column for enrichment and adsorption at a flow rate of 1 mL / min, and washing with water until the filtrate is colorless, discarding the filtrate, and then eluting with hydrochloric acid with a mass concentration of 18-19% (prepared with concentrated hydrochloric acid and water in a 1+1 volume ratio) until the manganese ion exchange resin and the iron ion exchange resin show their original colors, and then eluting with hydrochloric acid with a mass concentration of 18-19% (prepared with concentrated hydrochloric acid and water in a 1+1 volume ratio) 1.0 times the column volume of the ion exchange column, and collecting the eluate;

[0138] Precipitation detection: The eluate was first heated and concentrated at 120°C and then fixed to volume to obtain 50 mL (V0) of fixed solution; 1 mL (V1) of the fixed solution was measured and the Fe content in the fixed solution was measured by ion chromatography. 3+ The content is 0.511 mg / mL (a); 100 mL of 0.1 mol / L sodium hydroxide solution is added to the remaining fixed volume solution for precipitation, and the solution is filtered using a glass crucible. The filtered solid is washed with water until the pH value of the washing solution is neutral, and then dried and weighed to obtain a manganese-iron mixed solid with a mass of 106.24 mg (m2); the manganese-iron mixed solid is a mixture of MnO (OH) 2 and Fe (OH) 3; the manganese content Mn% is 6.20%, and the iron content Fe% is 5.09% calculated according to the following formulas;

[0139]

[0140]

[0141] Where:

[0142] M S1 is the relative molecular mass of MnO(OH)2, which is 104.938;

[0143] M Mn is the relative atomic mass of Mn, which is 54.93;

[0144] M S2 is the relative molecular mass of Fe(OH)3, which is 106.87;

[0145] M Fe is the relative atomic mass of Fe, which is 55.845;

[0146] m1 is the mass of the ferromanganese ore sample, in mg;

[0147] m2 is the mass of the ferromanganese mixed solid, in mg;

[0148] V0 is the volume of the constant solution obtained after the eluent is constant to volume, in mL;

[0149] V1 is the volume of the constant volume solution used for ion chromatography measurement, in mL;

[0150] a is Fe in the constant volume solution 3+ Content, unit: mg / mL.

[0151] Example 3

[0152] This embodiment provides a combined detection method for ferromanganese content in ferromanganese ore, the combined detection method comprising the following steps:

[0153] Sample dissolution: Weigh 0.5007 g (m1) of an iron-manganese ore sample, add acid to dissolve it at 100°C, and obtain a dissolved solution through a first solid-liquid separation; wherein the acid is a mixed acid solution of nitric acid and hydrochloric acid in a volume ratio of 1:1, and the nitric acid is prepared by using concentrated nitric acid and water in a volume ratio of 1+1, with a mass concentration of 33-35%, and the hydrochloric acid is prepared by using concentrated hydrochloric acid and water in a volume ratio of 1+1, with a mass concentration of 18-19%, and 150 mL of nitric acid and hydrochloric acid are measured to obtain a mixed acid solution;

[0154] Oxidation reaction: gradually add a hydrogen peroxide solution with a mass concentration of 35% to the dissolving solution for oxidation until the ultraviolet absorbance of the obtained reaction solution at 505nm no longer changes, and then heat the obtained oxidized solution at 200°C for 30 minutes to remove acid to obtain a Mn-containing 4+ with Fe 3+ Oxidizing liquid;

[0155] Column enrichment: prepare an ion exchange column loaded with manganese ion exchange resin and iron ion exchange resin, wherein the manganese ion exchange resin is Amberlite cation exchange resin CH-90, the iron ion exchange resin is Amberlite cation exchange resin IR-120, the mass ratio of the manganese ion exchange resin to the iron ion exchange resin is 2:1, and the total volume of the manganese ion exchange resin and the iron ion exchange resin is 3 times the volume of the oxidation solution; mix the manganese ion exchange resin and the iron ion exchange resin and wet-column them, wash the ion exchange column with water until the pH value of the washing solution is neutral and odorless, and obtain a pretreated ion exchange column;

[0156] Passing the oxidizing liquid through a pretreated ion exchange column for enrichment and adsorption at a flow rate of 1 mL / min, and washing with water until the filtrate is colorless, discarding the filtrate, and then eluting with hydrochloric acid with a mass concentration of 18-19% (prepared with concentrated hydrochloric acid and water in a 1+1 volume ratio) until the manganese ion exchange resin and the iron ion exchange resin show their original colors, and then eluting with hydrochloric acid with a mass concentration of 18-19% (prepared with concentrated hydrochloric acid and water in a 1+1 volume ratio) 2.0 times the column volume of the ion exchange column, and collecting the eluate;

[0157] Precipitation detection: The eluate was first heated and concentrated at 150°C and then fixed to volume to obtain 50 mL (V0) of fixed solution; 1 mL (V1) of the fixed solution was measured and the Fe content in the fixed solution was measured by ion chromatography. 3+ The content is 0.456 mg / mL (a); 400 mL of 0.1 mol / L sodium hydroxide solution is added to the remaining fixed volume solution for precipitation, and filtered using a glass sand core crucible, and the filtered solid is washed with water until the pH value of the washing liquid is neutral, and then dried and weighed to obtain a manganese-iron mixed solid with a mass of 94.81 mg (m2); the manganese-iron mixed solid is a mixture of MnO (OH) 2 and Fe (OH) 3; the manganese content Mn% is 5.55%, and the iron content Fe% is 4.55% calculated according to the following formulas;

[0158]

[0159]

[0160] Where:

[0161] M S1 is the relative molecular mass of MnO(OH)2, which is 104.938;

[0162] M Mn is the relative atomic mass of Mn, which is 54.938;

[0163] M S2 is the relative molecular mass of Fe(OH)3, which is 106.87;

[0164] M Fe is the relative atomic mass of Fe, which is 55.845;

[0165] m1 is the mass of the ferromanganese ore sample, in mg;

[0166] m2 is the mass of the ferromanganese mixed solid, in mg;

[0167] V0 is the volume of the constant solution obtained after the eluent is constant to volume, in mL;

[0168] V1 is the volume of the constant volume solution used for ion chromatography measurement, in mL;

[0169] a is Fe in the constant volume solution 3+ Content, unit: mg / mL.

[0170] Comparative Example 1

[0171] This comparative example provides a combined detection method for the content of manganese iron in ferromanganese ore. Compared with Example 1, the only difference is that: a ferromanganese ore sample with a mass of 0.5014 g (m1) as that of Example 1 is weighed, and during the column enrichment process, the mass ratio of the manganese ion exchange resin to the iron ion exchange resin is 1:4; specifically as follows:

[0172] During the precipitation detection process, ion chromatography was used to measure the Fe 3+ The content is 0.214 mg / mL (a), and a manganese-iron mixed solid with a mass of 55.64 mg (m2) is obtained; according to the formula, the manganese content Mn% is calculated to be 3.79%, and the iron content Fe% is 2.13%.

[0173] Comparative Example 2

[0174] This embodiment provides a combined detection method for the content of ferromanganese in ferromanganese ore. Compared with Example 1, the only difference is that: a ferromanganese ore sample with a mass of 0.5012 g (m1) as that of Example 1 is weighed, and nitric acid is used as an oxidant during the oxidation reaction; the details are as follows:

[0175] Oxidation reaction: gradually add 0.5% nitric acid solution to the dissolving solution for oxidation until the ultraviolet absorbance of the obtained reaction solution at 505 nm no longer changes, and then heat the obtained oxidized solution at 200° C. for 30 minutes to remove acid to obtain an oxidized solution.

[0176] During the precipitation detection process, ion chromatography was used to measure the Fe 3+ The content is 0.396 mg / mL (a), and a manganese-iron mixed solid with a mass of 67.46 mg (m2) is obtained; according to the formula, the manganese content Mn% is calculated to be 3.23%, and the iron content Fe% is 3.95%.

[0177] The relevant numerical results of the above-mentioned Examples 1-3 and Comparative Examples 1-2 are summarized in Table 1.

[0178] Table 1

[0179] project <![CDATA[m1 / g]]> <![CDATA[V0 / mL]]> <![CDATA[V1 / mL]]> a / mg / mL <![CDATA[m2 / mg]]> Mn% / 100% Fe% / 100% Example 1 0.5010 50 1 0.605 124.25 7.20 6.04 Example 2 0.5022 50 1 0.511 106.24 6.20 5.09 Example 3 0.5007 50 1 0.456 94.81 5.55 4.55 Comparative Example 1 0.5014 50 1 0.214 55.64 3.79 2.13 Comparative Example 2 0.5012 50 1 0.336 59.54 3.23 3.95

[0180] It can be seen from Table 1 that:

[0181] (1) The combined detection method of the present invention comprises the following steps: adding an iron manganese ore sample to an acid solution for dissolution, oxidizing Mn and Fe in the solution to Mn 4+ with Fe 3+ The high-valent state of Mn is enriched, adsorbed and eluted in sequence using a pretreated ion exchange column to achieve 4+ with Fe 3+ The collected eluate was fixed to volume, and a small portion of the fixed volume was taken to measure Fe 3+ The remaining fixed volume solution is added with precipitation alkali solution for precipitation to obtain a mixture of MnO(OH)2 and Fe(OH)3, and then the manganese content and iron content in the iron-manganese ore can be obtained by simple calculation, thus realizing the joint detection of manganese and iron content in the iron-manganese ore, which has the advantages of good stability, accuracy, effectiveness, low cost, etc., and is convenient for large-scale promotion and use;

[0182] (2) Comparing Example 1 with Comparative Example 1, since the mass ratio of manganese ion exchange resin to iron ion exchange resin in Comparative Example 1 was adjusted to 1:4, which exceeded the preferred range (1-3): (1-3) described in the present invention, the hydrogen bonding between the resins in the ion exchange column was enhanced, which greatly reduced the Mn 4+ with Fe 3+ The enrichment on the ion exchange column resulted in only a portion of Mn 4+ with Fe 3+ Entering the eluate for subsequent content detection, the manganese content and iron content calculated according to the formula are both reduced;

[0183] (3) Comparing Example 1 with Comparative Example 2, since nitric acid is used as the oxidant in Comparative Example 2, nitric acid is easily volatilized during the heating process, resulting in incomplete oxidation, so that only part of the low-valent manganese ions and iron ions are oxidized to Mn after the oxidation reaction. 4+ with Fe 3+ , which leads to a decrease in the manganese content and iron content calculated according to the formula; in addition, the gas generated by nitric acid during the heating process is easy to pollute the environment.

[0184] The present invention illustrates the detailed structural features of the present invention through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the components selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0185] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0186] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0187] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A combined detection method for ferromanganese content in ferromanganese ore, characterized in that: The joint detection method comprises the following steps: Sample dissolution: Weigh the iron-manganese ore sample with a mass of m1, add acid solution to dissolve it, and obtain the dissolved solution after the first solid-liquid separation; Oxidation reaction: Add an oxidant to the solution to oxidize it to obtain 4+ with Fe 3+ Oxidizing liquid; Column enrichment: The oxidized liquid is passed through a pretreated ion exchange column for enrichment and adsorption, and washed with water until the filtrate is colorless, the filtrate is discarded, and then eluted with a desorption acid solution, and the eluate is collected; The ion exchange column is filled with manganese ion exchange resin and iron ion exchange resin; The pretreatment comprises mixing the manganese ion exchange resin and the iron ion exchange resin and wet loading the mixture onto a column, and washing the ion exchange column with water until the pH value of the washing solution is neutral and odorless; Precipitation detection: The eluate is fixed to volume to obtain a fixed volume solution with a volume of V0; the fixed volume solution with a volume of V1 is measured, and the Fe content in the fixed volume solution is measured by ion chromatography. 3+ The content is a; Add precipitation alkali solution to the remaining fixed volume solution for precipitation, and sequentially undergo a second solid-liquid separation, washing, drying and weighing to obtain a manganese-iron mixed solid with a mass of m2; the manganese-iron mixed solid is a mixture of MnO(OH)2 and Fe(OH)3; the manganese content Mn% and the iron content Fe% are calculated according to the following formulas: Where: M S1 is the relative molecular mass of MnO(OH)2; M Mn is the relative atomic mass of Mn; M S2 is the relative molecular mass of Fe(OH)3; M Fe is the relative atomic mass of Fe; m1 is the mass of the ferromanganese ore sample, in mg; m2 is the mass of the ferromanganese mixed solid, in mg; V0 is the volume of the constant solution obtained after the eluent is constant to volume, in mL; V1 is the volume of the constant volume solution used for ion chromatography measurement, in mL; a is Fe in the constant volume solution 3+ Content, unit: mg / mL.

2. The joint detection method according to claim 1, characterized in that: The acid solution includes a mixed acid solution composed of any two of nitric acid, hydrochloric acid, sulfuric acid and phosphoric acid.

3. The joint detection method according to claim 2, characterized in that: The acid solution is a mixed acid solution of nitric acid and hydrochloric acid in a volume ratio of 1:

1.

4. The joint detection method according to claim 2, characterized in that: The mass concentration of the nitric acid is 33-35%.

5. The joint detection method according to claim 2, characterized in that: The mass concentration of the hydrochloric acid is 18-19%.

6. The joint detection method according to claim 2, characterized in that: The molar concentration of the sulfuric acid is 0.75-1.25 mol / L.

7. The joint detection method according to claim 2, characterized in that: The molar concentration of the phosphoric acid is 0.75-1.25 mol / L.

8. The joint detection method according to claim 1, characterized in that: The ratio of the mass of the ferromanganese ore sample to the volume of the acid solution is 1 g: (200-600) mL.

9. The joint detection method according to claim 1, characterized in that: The dissolving temperature is 100-200°C.

10. The joint detection method according to claim 1, characterized in that: The oxidizing agent includes hydrogen peroxide solution and / or ozone.

11. The joint detection method according to claim 10, characterized in that: The mass concentration of the hydrogen peroxide solution is 5-35%.

12. The joint detection method according to claim 10, characterized in that: During the oxidation reaction, the hydrogen peroxide solution is gradually added for oxidation until the ultraviolet absorbance of the obtained reaction solution at 505 nm no longer changes.

13. The joint detection method according to claim 1, characterized in that: After the oxidation reaction and before the column enrichment, the oxidation liquid is heated to remove acid.

14. The joint detection method according to claim 13, characterized in that: The temperature of the heating deacidification treatment is 100-200°C.

15. The joint detection method according to claim 13, characterized in that: The heating and deacidification treatment takes 10-60 minutes.

16. The joint detection method according to claim 1, characterized in that: The manganese ion exchange resin is Amberlite cation exchange resin, and its model includes any one of CH-90, FEROX, D113, SJ-004, T-52H or KATALOXLIGHT.

17. The joint detection method according to claim 1, characterized in that: The iron ion exchange resin is Amberlite cation exchange resin, and the model includes any one of IR-120, T-IRR, A-21S, KP-759, TP207 or D401.

18. The joint detection method according to claim 1, characterized in that: The mass ratio of the manganese ion exchange resin to the iron ion exchange resin is (1-3):(1-3).

19. The joint detection method according to claim 1, characterized in that: The total volume of the manganese ion exchange resin and the iron ion exchange resin is more than 3 times the volume of the oxidizing solution.

20. The joint detection method according to claim 1, characterized in that: The flow rate of the enrichment adsorption is 1-1.5 mL / min.

21. The joint detection method according to claim 1, characterized in that: The desorption acid solution includes any one of hydrochloric acid, sulfuric acid or nitric acid, or a combination of at least two of them.

22. The joint detection method according to claim 21, characterized in that: The desorption acid solution is hydrochloric acid with a mass concentration of 18-19%.

23. The joint detection method according to claim 1, characterized in that: The completion standard of the elution is: firstly elute with the desorption acid solution until the ion exchange column presents the original color, and then elute with the desorption acid solution which is 1-2 times of the column volume of the ion exchange column.

24. The joint detection method according to claim 1, characterized in that: After the elution and before the volume adjustment, the eluate is heated and concentrated.

25. The joint detection method according to claim 1, characterized in that: The precipitation alkali solution includes a sodium hydroxide solution with a concentration of 0.08-0.12 mol / L.

26. The joint detection method according to claim 1, characterized in that: The volume ratio of the remaining total volumetric solution to the precipitation alkali solution is 1:(2-8).

27. The joint detection method according to claim 1, characterized in that: The second solid-liquid separation is carried out by filtering using a glass sand core crucible.

28. The joint detection method according to claim 1, characterized in that: The completion standard of the washing is: washing with water until the pH value of the obtained washing liquid is neutral.

29. The joint detection method according to claim 1, characterized in that: The joint detection method comprises the following steps: Sample dissolution: weighing a ferromanganese ore sample with a mass of m1, adding acid solution to dissolve it at 100-200°C, and obtaining a dissolved solution through a first solid-liquid separation; wherein the acid solution is a mixed acid solution of nitric acid and hydrochloric acid in a volume ratio of 1:1, and the mass concentration of the nitric acid is 33-35%, and the mass concentration of the hydrochloric acid is 18-19%; the ratio of the mass of the ferromanganese ore sample to the volume of the acid solution is 1g:(200-600)mL; Oxidation reaction: gradually add a hydrogen peroxide solution with a mass concentration of 5-35% to the dissolved solution for oxidation until the ultraviolet absorbance of the obtained reaction solution at 505nm no longer changes, and then heat the obtained oxidized solution at 100-200°C for 10-60min to remove acid, thereby obtaining a Mn-containing 4+ with Fe 3+ Oxidizing liquid; Column enrichment: preparing an ion exchange column loaded with manganese ion exchange resin and iron ion exchange resin, wherein the manganese ion exchange resin is Amberlite cation exchange resin, and its model includes any one of CH-90, FEROX, D113, SJ-004, T-52H or KATALOX LIGHT, and the iron ion exchange resin is Amberlite cation exchange resin, and its model includes any one of IR-120, T-IRR, A-21S, KP-759, TP207 or D401, and the mass ratio of the manganese ion exchange resin to the iron ion exchange resin is (1-3): (1-3), and the total volume of the manganese ion exchange resin and the iron ion exchange resin is more than 3 times the volume of the oxidation solution; mixing the manganese ion exchange resin and the iron ion exchange resin, and wet-loading the column, and washing the ion exchange column with water until the pH value of the washing solution is neutral and odorless, thereby obtaining a pretreated ion exchange column; Passing the oxidized liquid through a pretreated ion exchange column for enrichment and adsorption at a flow rate of 1-1.5 mL / min, washing with water until the filtrate is colorless, discarding the filtrate, and then eluting with hydrochloric acid with a mass concentration of 18-19% until the manganese ion exchange resin and the iron ion exchange resin show their original colors, and then eluting with hydrochloric acid with a mass concentration of 18-19% that is 1-2 times the column volume of the ion exchange column, and collecting the eluate; Precipitation detection: The eluate is first heated and concentrated and then fixed to volume to obtain a fixed volume solution with a volume of V0; the fixed volume solution with a volume of V1 is measured, and the Fe content in the fixed volume solution is measured by ion chromatography. 3+ The content is a; a sodium hydroxide solution with a concentration of 0.08-0.12 mol / L is added to the remaining total volume solution for precipitation, the volume ratio of the remaining total volume solution to the precipitation alkali solution is 1: (2-8), and a glass sand core crucible is used for filtration, and the filtered solid is washed with water until the pH value of the washing liquid is neutral, and then dried and weighed to obtain a manganese iron mixed solid with a mass of m2; the manganese iron mixed solid is a mixture of MnO (OH) 2 and Fe (OH) 3; the manganese content Mn% and the iron content Fe% are calculated according to the following formulas: Where: M S1 is the relative molecular mass of MnO(OH)2; M Mn is the relative atomic mass of Mn; M S2 is the relative molecular mass of Fe(OH)3; M Fe is the relative atomic mass of Fe; m1 is the mass of the ferromanganese ore sample, in mg; m2 is the mass of the ferromanganese mixed solid, in mg; V0 is the volume of the constant solution obtained after the eluent is constant to volume, in mL; V1 is the volume of the constant volume solution used for ion chromatography measurement, in mL; a is Fe in the constant volume solution 3+ Content, unit: mg / mL.

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