A method for calculating the dosage of ion-type rare earth ore leaching agent

Abstract

The application discloses a kind of ion type rare earth leaching agent dosage calculation method, it is related to the field of leaching beneficiation.Ion type rare earth leaching agent dosage calculation method includes: test pure lanthanum mineral surface charge density;Determine the ammonium ion content and lanthanum ion content of pure lanthanum mineral solid phase adsorption, determine the relationship between the relative effective charge coefficient of lanthanum ion and ammonium ion and ionic strength;Determine the relationship between Donnan equilibrium selection coefficient and ammonium ion activity in supernatant;According to ion activity coefficient, Donnan equilibrium selection coefficient and ammonium ion and lanthanum ion exchange ratio fitting calculation, the relationship between the single consumption of leaching agent ammonium sulfate and leaching rate is obtained.Ion type rare earth leaching agent dosage calculation method comprehensively considers the surface potential variation of ion type rare earth ore sample and the effective charge variation of ammonium ion and lanthanum ion under different ionic strength, to Donnan model describes leaching process, and proposes the calculation model of leaching agent ammonium sulfate single consumption for different ore and different target leaching rate, reduces rare earth leaching rate calculation error.

Description

Technical Field

[0001] This application relates to the field of mineral leaching and beneficiation, and more specifically, to a method for calculating the dosage of ion-type rare earth leaching agents. Background Technology

[0002] In ion-adsorption rare earth ores, rare earth elements are mainly adsorbed onto clay minerals in the form of hydrated or hydroxyl hydrated ions. Therefore, chemical leaching is the primary method of extraction. The amount of leaching agent used during extraction is a major factor affecting the resource recovery rate of ion-adsorption rare earth ores. Excessive leaching agent usage leads to ammonia nitrogen pollution and increases production costs; insufficient leaching agent usage results in low leaching efficiency and inadequate rare earth resource recovery. Therefore, quantitatively characterizing the leaching mechanism by describing the adsorption of cations and desorption of rare earth ions in the leaching agent, and establishing a calculation model for leaching agent usage, is of great significance for achieving efficient extraction and protecting the mining environment.

[0003] Currently, there are no industry standards for the dosage of leaching agents, and research largely relies on field experience. Patent CN107190144B discloses a method for calculating the dosage of ammonium sulfate in in-situ leaching of ionic rare earth minerals. Based on the chemical reaction equation between rare earth ions and ammonium ions, it establishes a calculation model using the reaction equilibrium constant to calculate the minimum and maximum values ​​of ammonium sulfate consumption. Patent CN111180017B discloses another method for calculating the dosage of ionic rare earth leaching agents. This method uses a binary desorption equilibrium model to divide ammonium consumption in leaching into three parts: ion exchange consumption, specific adsorption consumption, and consumption to maintain the leaching agent concentration. The corresponding leaching agent dosage is then calculated based on the DED model. The above schemes provide some guidance for calculating the amount of leaching agent, but none of them take into account that the essence of the mining process of ion-type rare earth minerals is the adsorption / desorption of ions under the action of the electric field on the surface of the ore. As a result, the above calculations of the amount of leaching agent for ion-type rare earth minerals do not reveal the essence of the desorption of rare earth ions and cannot be adapted to the conditions of different mineral sample properties in different regions.

[0004] Therefore, a method is needed to calculate the unit consumption of leaching agent for different mineral soils and different target leaching rates. Summary of the Invention

[0005] The purpose of this application is to provide a method for calculating the dosage of ionic rare earth leaching agents. By comprehensively considering the changes in surface potential of ionic rare earth ore samples and the changes in effective charge of ammonium ions and lanthanum ions under different ionic intensities, a calculation model for the consumption of ammonium sulfate leaching agent under different ore types and target leaching rates is proposed using the Daonan model to characterize the leaching process, thereby reducing the calculation error of rare earth leaching rate.

[0006] This application is implemented as follows:

[0007] This application provides a method for calculating the dosage of ion-type rare earth leaching agent, which includes the following steps:

[0008] Calculate the charge density σ0 on the surface of pure lanthanum minerals;

[0009] Adsorption and desorption experiments were conducted on pure lanthanum minerals. The concentrations of ammonium ions and lanthanum ions in the supernatant were measured, and the content of ammonium ions adsorbed by the pure lanthanum minerals in the solid phase was calculated. and lanthanum ion content

[0010] Determine the relative effective charge coefficients of lanthanum and ammonium ions. The exchange ratio ω of ammonium ions and lanthanum ions was calculated based on the relationship with ionic strength I.

[0011] Determine the equilibrium selectivity coefficient k of the South China Sea and the ammonium ion activity in the supernatant. Relationship;

[0012] Based on the ion activity coefficient γ i The relationship between the consumption of ammonium sulfate as a leaching agent and the leaching rate was obtained by fitting the equilibrium selectivity coefficient k and the exchange ratio ω of ammonium ions and lanthanum ions.

[0013] In some alternative embodiments, pure lanthanum minerals are prepared using the following steps:

[0014] The predetermined mass of rare earth ore was mixed with lanthanum sulfate solution and stirred for 1-3 hours, followed by solid-liquid separation. The above steps were repeated at least 3 times to obtain a sample.

[0015] Wash the sample with deionized water until the concentration of lanthanum ions in the washing solution is below 0.005 mmol / L, and then dry the sample.

[0016] In some alternative implementations, testing the charge density on the surface of pure lanthanum minerals includes the following steps:

[0017] Testing the lanthanum ion grade Q of pure lanthanum minerals in the ionic phase c and specific surface area S;

[0018] The surface charge density of pure lanthanum minerals is calculated using the following formula;

[0019]

[0020] In the formula: σ0 is the surface charge density, C / m 2 ; For La 3+ The electricity price; Q c Lanthanum ion grade in ionic phase, g / g; F is Faraday constant; ρ is the relative molar mass of lanthanum ions, taken as 138.91 g / mol; S is the specific surface area of ​​pure lanthanum mineral, m².2 / g.

[0021] In some alternative implementations, adsorption and desorption tests of pure lanthanum minerals are performed to determine the content of ammonium ions adsorbed on the solid phase of the pure lanthanum minerals. and lanthanum ion content Includes the following steps:

[0022] Pure lanthanum minerals were added to ammonium sulfate solutions of different concentrations and reacted at a preset temperature for 4-10 hours. The supernatant was then obtained by solid-liquid separation.

[0023] The concentrations of ammonium ions and lanthanum ions in the supernatant were measured separately, and the activity of ammonium ions in the supernatant was calculated. and lanthanum ion activity Calculate the ammonium ion content adsorbed on the solid phase of pure lanthanum minerals. and lanthanum ion content

[0024] In some alternative implementations, the relative effective charge coefficients of lanthanum ions and ammonium ions are determined. The relationship with ionic strength I includes the following steps:

[0025] The relative effective charge coefficients of lanthanum and ammonium ions are calculated using the following formula. and

[0026]

[0027] In the formula, and The ammonium ion content and lanthanum ion content adsorbed on the solid phase of pure lanthanum mineral are shown in mol / g; β i is the relative effective charge coefficient of ion i; Let V be the surface potential. and ρ represents the ammonium and lanthanum ion activities in the supernatant, in mol / L; R is the gas constant, with a value of 8.314 J / (mol·K); T is the absolute temperature, in K; F is the Faraday constant; S is the specific surface area of ​​pure lanthanum mineral, in m². 2 / g; κ is the Debye parameter, nm -1 m is a coefficient related to electrolyte type; ε is the extraction rate;

[0028] The relative effective charge coefficients of lanthanum ions and ammonium ions were obtained by mathematical fitting using the following formulas. and Relationship with ionic strength I;

[0029] β=blnI+d;

[0030] In the formula: I is the ionic strength, mol / L; b and d are coefficients; β is the relative effective charge coefficient of lanthanum ion or ammonium ion.

[0031] In some alternative implementations, the ammonium ion to lanthanum ion exchange ratio ω is calculated using the following formula:

[0032]

[0033] In the formula: Z i The valence of i ions; β i denoted as i, representing the relative effective charge coefficient of the i-ion.

[0034] In some alternative implementations, the equilibrium selectivity coefficient k of the Dornan model is determined in relation to the ammonium ion activity. The relationship includes the following steps:

[0035] Based on the ammonium ion activity in the supernatant The equilibrium selectivity coefficient k of the Dornan model and the ammonium ion activity in the supernatant were obtained by mathematical fitting using the following formula. The relationship between them:

[0036]

[0037] In the formula, k is the equilibrium selection coefficient of the Downan model; f is a coefficient; This represents the activity of ammonium ions in the supernatant.

[0038] In some alternative implementations, the ion activity coefficient γ i It is calculated based on the ion hydration radius and ion strength.

[0039] In some alternative implementations, based on the ion activity coefficient γ i The following fitting formula was used to calculate the relationship between the amount of ammonium sulfate used as the leaching agent and the leaching rate when calculating the equilibrium selectivity coefficient k and the exchange ratio ω of ammonium ions and lanthanum ions:

[0040]

[0041] In the formula, This refers to the amount of ammonium sulfate used, in g / g; The initial amount of ammonium ions, in mol / g; γ is the molar mass of ammonium sulfate, in g / mol; i ω is the activity coefficient of i ions; ω is the exchange ratio of ammonium ions to lanthanum ions; ε is the leaching rate, %; θ is the rare earth ore grade, mol / g; m 矿 denoted as mass of rare earth ore, g; k is the Daonan equilibrium selectivity coefficient.

[0042] The beneficial effects of this application are as follows: The method for calculating the dosage of ionic rare earth leaching agent provided in this application includes the following steps: testing the charge density σ0 on the surface of pure lanthanum minerals; conducting adsorption and desorption tests on pure lanthanum minerals to obtain the content of ammonium ions adsorbed on the solid phase of pure lanthanum minerals. and lanthanum ion content Determine the relative effective charge coefficients of lanthanum and ammonium ions. Relationship with ionic strength I; Determine the relationship between the equilibrium selectivity coefficient k and the ammonium ion activity in the supernatant. The relationship; based on the ion activity coefficient γ i The relationship between the specific consumption of ammonium sulfate as a leaching agent and the leaching rate was obtained by fitting the equilibrium selectivity coefficient k and the exchange ratio ω of ammonium and lanthanum ions. The method for calculating the dosage of ionic rare earth leaching agents provided in this application comprehensively considers the changes in the surface potential of ionic rare earth samples and the changes in the effective charge of ammonium and lanthanum ions under different ionic intensities. Using the Daonan model to characterize the leaching process, a calculation model for the specific consumption of ammonium sulfate as a leaching agent under different ore types and target leaching rates is proposed, providing a theoretical basis for rationally determining the dosage of leaching agents. The calculated rare earth leaching rate has an error of only within 0.82% compared to the actual rare earth leaching rate. Detailed Implementation

[0043] The embodiments described in this application are only a portion of, not all, of the embodiments described herein. Therefore, the detailed description of the embodiments provided below is not intended to limit the scope of the claimed application, but merely represents selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0044] This application provides a method for calculating the dosage of ion-type rare earth leaching agent, which includes the following steps:

[0045] Step 1: Preparation of pure lanthanum mineral; Mix a predetermined mass of rare earth ore with lanthanum sulfate solution and stir for 1-3 hours, then separate the solid and liquid phases. Repeat this step at least 3 times to obtain a sample; Wash the sample with deionized water until the lanthanum ion concentration in the washing solution is below 0.005 mmol / L, and dry the sample to obtain pure lanthanum mineral. Optionally, the rare earth ore and lanthanum sulfate solution are mixed in a 1:1 mass ratio, and the concentration of the lanthanum sulfate solution is in the range of 0.005-0.020 mol / L.

[0046] Step 2: Test the charge density σ0 on the surface of pure lanthanum minerals;

[0047] Testing the lanthanum ion grade Q of pure lanthanum minerals in the ionic phase c and specific surface area S;

[0048] The surface charge density of pure lanthanum minerals is calculated using the following formula;

[0049]

[0050] In the formula: σ0 is the surface charge density, C / m 2 ; For La 3+ The electricity price; Q c Lanthanum ion grade in ionic phase, g / g; F is Faraday constant; ρ is the relative molar mass of lanthanum ions, taken as 138.91 g / mol; S is the specific surface area of ​​pure lanthanum mineral, m². 2 / g.

[0051] Step 3: Conduct adsorption and desorption tests on pure lanthanum minerals to obtain the content of ammonium ions adsorbed on the solid phase of pure lanthanum minerals. and lanthanum ion content

[0052] Pure lanthanum minerals were added to ammonium sulfate solutions of different concentrations and reacted at a preset temperature for 4-10 hours. The supernatant was then obtained by solid-liquid separation.

[0053] The concentrations of ammonium ions and lanthanum ions in each supernatant were measured, and the activity of ammonium ions in the supernatant was calculated. and lanthanum ion activity The ammonium ion content adsorbed on the solid phase of pure lanthanum minerals was calculated. and lanthanum ion content

[0054] Step 4: Determine the relative effective charge coefficients of lanthanum ions and ammonium ions. Relationship with ionic strength I;

[0055] The relative effective charge coefficients of lanthanum and ammonium ions are calculated using the following formula. and

[0056]

[0057] In the formula, and The ammonium ion content and lanthanum ion content are determined by the solid-phase adsorption of pure lanthanum minerals; β i denoted as the relative effective charge coefficient of ion i, where ion i is either an ammonium ion or a lanthanum ion; Let V be the surface potential. and ρ represents the ammonium and lanthanum ion activities in the supernatant, in mol / L; R is the gas constant, with a value of 8.314 J / (mol·K); T is the absolute temperature, in K; F is the Faraday constant; S is the specific surface area of ​​pure lanthanum mineral, in m². 2 / g; κ is the Debye parameter. I represents ionic strength; m represents a parameter related to electrolyte type; ε represents leaching rate;

[0058] The relative effective charge coefficients of lanthanum ions and ammonium ions were obtained by mathematical fitting using the following formulas. and Relationship with ionic strength I;

[0059] β=blnI+d;

[0060] In the formula: I is the ionic strength, mol / L; b and d are coefficients; β is the relative effective charge coefficient of lanthanum ion or ammonium ion.

[0061] The exchange ratio ω of ammonium ions and lanthanum ions was calculated using the following formula:

[0062]

[0063] In the formula: Z i The valence of i ions; β i denoted as the relative effective charge coefficient of ion i; ion i can be either ammonium ion or lanthanum ion.

[0064] Step 5: Determine the equilibrium selectivity coefficient k of the South China Sea and the ammonium ion activity in the supernatant. Relationship;

[0065] Based on the amount of ammonium ion adsorption in the solid phase of pure lanthanum mineral and the activity of ammonium ions in the supernatant The equilibrium selectivity coefficient k and ammonium ion activity of the Dornan model were obtained by mathematical fitting using the following formula. The relationship between them:

[0066]

[0067] In the formula, k is the equilibrium selection coefficient of the Dornan model; f is a coefficient. This represents the activity of ammonium ions in the supernatant.

[0068] Step 6: Based on the ion activity coefficient γ i The equilibrium selectivity coefficient k and the exchange ratio ω of ammonium ions and lanthanum ions were fitted and calculated using the following formula to obtain the relationship between the consumption of ammonium sulfate as leaching agent and the leaching rate:

[0069]

[0070] In the formula, This refers to the amount of ammonium sulfate used, in g / g; The initial amount of ammonium ions, mol / g; γ iω is the activity coefficient of i ions; ω is the exchange ratio of ammonium ions to lanthanum ions; ε is the leaching rate, %; θ is the rare earth ore grade, mol / g; m 矿 denoted as mass of rare earth ore, g; k is the Daonan equilibrium selectivity coefficient.

[0071] The method for calculating the dosage of ionic rare earth leaching agent provided in this application comprehensively considers the changes in the surface potential of the ore sample during leaching and the changes in the effective charge of ammonium ions and lanthanum ions under different ionic intensities. Using the Daonan model to characterize the leaching process, a calculation model for the specific consumption of ammonium sulfate leaching agent under different rare earth ores and different target leaching rates is proposed. This provides a theoretical basis for rationally determining the dosage of leaching agent. The dosage of leaching agent determined by the method for calculating the dosage of ionic rare earth leaching agent provided in this application is scientific and reasonable, and the error between it and the actual rare earth leaching rate is within 0.82%.

[0072] Based on the essence of the adsorption and desorption process of ions on the surface of rare earth ore, the leaching agent solution and rare earth ore are regarded as the Daonan system. The edge of the counterion adsorption layer in the double electric layer of rare earth ore surface is set as the imaginary Daonan surface. The inside of the Daonan surface is regarded as the inner phase of the system, including the negatively charged rare earth ore colloid that cannot pass through the imaginary Daonan surface and the counterions adsorbed by the rare earth ore colloid. The outside of the Daonan surface is the outer phase of the system, which is a homogeneous leaching agent solution.

[0073] Therefore, the selectivity coefficients of ammonium ions and rare earth ions (lanthanum ions) during the mining of ion-adsorption rare earth minerals can be expressed as:

[0074]

[0075] In the formula: k is the southbound balance selection coefficient; σ i i is the amount of i ions adsorbed per unit mass on the mineral surface, in mol / g; a i yes i Ion activity in bulk solution, mol / L; Z i The valence of i ions; β i denoted as , where is the relative effective charge coefficient of the i-ion; F is the Faraday constant, with a value of 9.65 × 10⁻⁶. 4 C / mol; ν is the surface potential, V; R is the gas constant, with a value of 8.314 J / (mol·K); T is the absolute temperature, K.

[0076] By substituting the expressions for the rare earth concentration and rare earth ion leaching rate corresponding to the original ore grade into the generated rare earth ion concentration (lanthanum ion), the generated ammonium ion adsorbate concentration, and the consumed rare earth ion concentration, the following relationship can be obtained:

[0077]

[0078] In the formula: The initial amount of ammonium ions, mol / g; γ i ω is the activity coefficient of i ions; ω is the exchange ratio of ammonium ions to lanthanum ions; ε is the leaching rate, %; θ is the ore grade, mol / g; m 矿 denoted as mass of rare earth ore, g; k is the Daonan equilibrium selectivity coefficient.

[0079] The above formula represents the amount of ammonium ions required to leach a unit mass of ion-adsorption rare earth ore. By converting the formula and units, the following calculation formula can be obtained:

[0080]

[0081] In the formula: This refers to the amount of ammonium sulfate used, in g / g; The initial amount of ammonium ions, mol / g; γ i ω is the activity coefficient of i ions; ω is the exchange ratio of ammonium ions to lanthanum ions; ε is the leaching rate, %; θ is the ore grade, mol / g; m 矿 denoted as mass of rare earth ore, g; k is the Daonan equilibrium selectivity coefficient.

[0082] The following detailed description of the features and performance of the method for calculating the dosage of ion-type rare earth leaching agent of this application is provided in conjunction with embodiments.

[0083] Example 1

[0084] Using the ion-type rare earth leaching agent dosage calculation method provided in the embodiments of this application, a closed-door experiment was conducted in a rare earth mining area in southern Jiangxi. Representative ion-type rare earth ore samples were prepared by mixing ore samples from different locations collected on-site. Adsorption and desorption tests were performed on these ion-type rare earth ore samples to obtain key parameters. Column leaching tests were then conducted using the calculated results as experimental conditions to verify the reliability of the calculation results.

[0085] Step 1: Prepare pure lanthanum mineral. Take a certain mass of rare earth ore, add an equal mass of 0.0125 mmol / L lanthanum sulfate solution, stir for 2 hours to separate solid and liquid. Repeat the above solid-liquid separation operation of adding lanthanum sulfate solution and stirring 3 times to obtain a sample. Take deionized water to wash the surface of the sample to remove water-soluble lanthanum ions until the concentration of lanthanum ions in the washing solution is lower than 0.005 mmol / L. Dry the washed sample at 70℃ to obtain pure lanthanum mineral for later use.

[0086] Step 2: Test the surface charge density of pure lanthanum minerals;

[0087] The lanthanum ion grade Q of pure lanthanum minerals was tested using existing technology. c Its specific surface area S; calculate its surface charge density σ0 according to the following formula (1).

[0088]

[0089] In equation (1): σ0 is the surface charge density, C / m 2 ; For La 3+ The electricity price; Q c Lanthanum ion grade in ionic phase, g / g; F is Faraday constant; ρ is the relative molar mass of lanthanum ions, taken as 138.91 g / mol; S is the specific surface area of ​​pure lanthanum mineral, m². 2 / g.

[0090] The lanthanum ion content of the pure lanthanum mineral was 2.400 mg / g, and its specific surface area was 15.779 m². 2 / g; The surface charge density of pure lanthanum mineral is calculated to be 0.317 C / m according to equation (1). 2 .

[0091] Step 3: Conduct adsorption and desorption tests on pure lanthanum minerals to obtain the content of ammonium ions adsorbed on the solid phase of pure lanthanum minerals. and lanthanum ion content

[0092] Thirteen portions of pure lanthanum mineral obtained in step two were taken and added to ammonium sulfate solutions of different concentrations at a solid-liquid mass ratio of 1:5. The ammonium ion concentrations of the added ammonium sulfate solutions were 2 mmol / L, 4 mmol / L, 10 mmol / L, 20 mmol / L, 30 mmol / L, 40 mmol / L, 60 mmol / L, 80 mmol / L, 100 mmol / L, 120 mmol / L, 160 mmol / L, 200 mmol / L, and 300 mmol / L, totaling 13 different concentrations. The reaction was carried out at a certain temperature for 4 hours, and solid-liquid separation was performed. The concentrations of ammonium ions and lanthanum ions in the supernatant were measured, and the ionic strength I and the ammonium ion activity in the supernatant were calculated. and lanthanum ion activity Ammonium ion content in solid phase adsorption and lanthanum ion content The results are shown in Table 1.

[0093] Table 1 shows the calculated ionic strength, ion activity in the supernatant, and ion content adsorbed on the solid phase.

[0094]

[0095] Step 4: Determine the relative effective charge coefficients of lanthanum ions and ammonium ions. Relationship with ionic strength I;

[0096] The relative effective charge coefficients of lanthanum ions and ammonium ions are calculated using the following formula (2). and

[0097]

[0098] Substituting the ion concentration and ion content obtained in step three into equation (2), the relative effective charge coefficients of lanthanum ions and ammonium ions are calculated. and The relative effective charge coefficients of lanthanum ions and ammonium ions are obtained by mathematical fitting using the following equation (3). and The relationship between the ionic strength I and the strength I.

[0099] β=blnI+d (3)

[0100] Calculate the relationship between the relative effective charge coefficients of lanthanum ions and ammonium ions in pure lanthanum minerals and their ionic strength, where lanthanum ions are... ammonium ion is

[0101] Step 5: Determine the equilibrium selectivity coefficient k of the South China Sea and the ammonium ion activity in the supernatant. Relationship;

[0102] Calculate the ammonium ion activity in the supernatant based on the ion concentrations obtained in step three. Calculate the equilibrium selection coefficient k of the Daonan model and perform mathematical fitting using the following fitting formula (4):

[0103]

[0104] The equilibrium selectivity coefficient k and ammonium ion activity of the Dornan model were obtained. The relationship between them is

[0105] Step 6, based on the ion activity coefficient γ i The equilibrium selectivity coefficient k and the exchange ratio ω of ammonium ions and lanthanum ions were fitted and calculated using the following formula to obtain the relationship between the consumption of ammonium sulfate as leaching agent and the leaching rate:

[0106]

[0107] The ammonium sulfate concentration was determined to be 20 g / L. The ion activity coefficient was calculated using equation (6). It is 0.147. The value is 0.719, and equation (6) is the existing Debye-Hückel limit formula; in equation (6), Z i The valence of i ions, γ iLet be the ionic activity coefficient of ion i, I be the ionic strength, and B be a constant, which is 0.00328 at 25℃. The ion volume parameter is approximately equal to the effective radius of the hydrated ion; for lanthanum ions, it is 900 pm, and for ammonium ions, it is 300 pm. Substituting the ammonium ion activity in the supernatant into the fitting formula in step five, the equilibrium selectivity coefficient k of Daonan is calculated to be 0.666, and the exchange ratio ω between ammonium ions and lanthanum ions is 0.852. Substituting each parameter into equation (5) yields equation (7), which represents the relationship between the ammonium sulfate consumption and leaching rate in the rare earth minerals of this application embodiment. Substituting the corresponding leaching rate allows for the calculation of the ammonium sulfate consumption.

[0108]

[0109] Column leaching tests were conducted on mineral samples from southern Jiangxi. The specific consumption of ammonium sulfate was calculated using this model under the premise of rare earth leaching rates of 80%, 85%, and 90%. The tests used a 2% ammonium sulfate solution for leaching, followed by top water injection. Other specific parameters and test results are shown in Table 2. According to the calculation formula, for this mineral from southern Jiangxi, when the target rare earth leaching rate is 80%, 85%, and 90%, the calculated ammonium sulfate consumption is 4.48 g / g, 5.46 g / g, and 7.45 g / g, respectively, which were used as the amount of ammonium sulfate used in the column leaching process. The actual leaching rates were 80.66%, 85.69%, and 90.30%, respectively. The maximum error between the calculated and measured values ​​was 0.82%, indicating that the calculation method of this invention is close to the actual situation and has high practical value.

[0110] Table 2 Comparison of leaching rates calculated from the embodiments of this application and leaching rates obtained from actual ore leaching.

[0111]

[0112] The embodiments described above are some, but not all, of the embodiments of this application. The detailed description of the embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

Claims

1. A method for calculating the dosage of ion-type rare earth leaching agent, characterized in that, It includes the following steps: Calculate the charge density σ0 on the surface of pure lanthanum minerals; Adsorption and desorption experiments were conducted on the pure lanthanum mineral. The concentrations of ammonium ions and lanthanum ions in the supernatant were measured, and the content of ammonium ions adsorbed by the pure lanthanum mineral in the solid phase was calculated. and lanthanum ion content ; Determine the relative effective charge coefficients of lanthanum and ammonium ions. , With ionic strength I The relationship is determined by the following steps: The relative effective charge coefficients of lanthanum ions and ammonium ions are calculated using the following formula. and : ； In the formula, and The ammonium ion content and lanthanum ion content adsorbed on the solid phase of pure lanthanum mineral are expressed in mol / g. β i is the relative effective charge coefficient of ion i; Let V be the surface potential. and The values ​​represent the ammonium ion activity and lanthanum ion activity in the supernatant, in mol / L. The value is 8.314 J / (mol·K). T ρ is absolute temperature, K; F is Faraday constant; S is the specific surface area of ​​pure lanthanum mineral, m². 2 / g; For Debye parameters, nm -1 m is a coefficient related to electrolyte type; ε is the extraction rate; The relative effective charge coefficients of lanthanum ions and ammonium ions were obtained by mathematical fitting using the following formulas. and With ionic strength I Relationship; ； In the formula: denoted as ionic strength, mol / L; b and d are coefficients. β The relative effective charge coefficient of lanthanum ions or ammonium ions; The exchange ratio of ammonium ions and lanthanum ions is calculated using the following formula. ω : ； In the formula: Z i The valence of i ions; β i is the relative effective charge coefficient of ion i; Determine the balance selection coefficient of Daonan k With the activity of ammonium ions in the supernatant Relationship; Based on ion activity coefficient γ i Daonan Balanced Selection Coefficient k and the exchange ratio of ammonium ions and lanthanum ions ω The relationship between the consumption of ammonium sulfate leaching agent and the leaching rate was calculated using the following fitting formula: ； In the formula, This refers to the amount of ammonium sulfate used, in g / g; The initial amount of ammonium ions, in mol / g; is the molar mass of ammonium sulfate, in g / mol; γ i is the activity coefficient of ion i; The exchange ratio of ammonium ions to lanthanum ions; The extraction rate is %; Rare earth ore grade, mol / g; m 矿 The mass of rare earth ore is expressed in grams. k This represents the equilibrium selection coefficient for Daonan.

2. The method for calculating the dosage of ion-type rare earth leaching agent according to claim 1, characterized in that, The pure lanthanum mineral was prepared using the following steps: The predetermined mass of rare earth ore was mixed with lanthanum sulfate solution and stirred for 1-3 hours, followed by solid-liquid separation. The above steps were repeated at least 3 times to obtain a sample. Wash the sample with deionized water until the concentration of lanthanum ions in the washing solution is below 0.005 mmol / L, and then dry the sample.

3. The method for calculating the dosage of ion-type rare earth leaching agent according to claim 1, characterized in that, Testing the charge density on the surface of pure lanthanum minerals includes the following steps: The lanthanum ion grade Q of the ionic phase of the pure lanthanum mineral was tested. c and specific surface area S; The surface charge density of the pure lanthanum mineral was calculated using the following formula; ； In the formula: σ0 is the surface charge density, C / m 2 ; For La 3+ The electricity price; Q c Lanthanum ion grade in ionic phase, g / g; F is Faraday constant; ρ is the relative molar mass of lanthanum ions, taken as 138.91 g / mol; S is the specific surface area of ​​pure lanthanum mineral, m². 2 / g.

4. The method for calculating the dosage of ion-type rare earth leaching agent according to claim 1, characterized in that, The content of ammonium ions adsorbed on the solid phase of pure lanthanum mineral was obtained by conducting adsorption and desorption experiments on pure lanthanum mineral. and lanthanum ion content Includes the following steps: The pure lanthanum mineral was added to ammonium sulfate solutions of different concentrations and reacted at a preset temperature for 4-10 hours, followed by solid-liquid separation to obtain the supernatant. The concentrations of ammonium ions and lanthanum ions in the supernatant were measured respectively, and the activity of ammonium ions in the supernatant was calculated. and lanthanum ion activity Calculate the ammonium ion content adsorbed on the solid phase of the pure lanthanum mineral. and lanthanum ion content .

5. The method for calculating the dosage of ion-type rare earth leaching agent according to claim 3, characterized in that, Determine the equilibrium selectivity coefficient k and ammonium ion activity in the Daonan model. The relationship includes the following steps: Based on the ammonium ion activity in the supernatant The equilibrium selectivity coefficient k of the Dornan model and the ammonium ion activity in the supernatant were obtained by mathematical fitting using the following formula. The relationship between them: ； In the formula, k is the equilibrium selection coefficient of the Downan model; f is a coefficient; This represents the activity of ammonium ions in the supernatant.

6. The method for calculating the dosage of ion-type rare earth leaching agent according to claim 1, characterized in that, The ion activity coefficient γ i It is calculated based on the ion hydration radius and ion strength.

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