A method for detecting magnesium content in molybdenum concentrate

Abstract

The invention introduces a method for detecting magnesium content in molybdenum concentrate, and relates to the technical field of element content detection. The specific steps are as follows: S1: weigh 0.1-0.2g of molybdenum concentrate sample, accurate to 0.0001g; S2: prepare molybdenum concentrate sample solution and molybdenum concentrate blank solution; S3: prepare working curve solution; S4: detection. The detection method of the invention does not require separation, enrichment and other complicated operations in the sample pretreatment process, and only requires acid treatment in the sample operation, without matrix separation. The configured molybdenum concentrate sample solution is sucked into the instrument for determination, and the magnesium content in the sample can be displayed instantly, greatly shortening the determination time; the operation is simple, efficient, and sensitive, the detection limit is 0.34mg / L, the determination line is low, the spike recovery rate is 96%~105%, the determination range is 0.0050%~4.28%, the determination range is wide, the precision is high, and it is suitable for rapid detection of product quality in production.

Description

Technical Field

[0001] The invention relates to the technical field of element content detection, and in particular to a method for detecting magnesium content in molybdenum concentrate. Background Art

[0002] Molybdenum concentrate is the most common molybdenum-containing mineral. About 99% of the world's magnesium metal is extracted from molybdenum concentrate. It can be seen that the economic value of molybdenum concentrate is great. Therefore, in-depth research on molybdenum concentrate has important theoretical and practical significance. In the existing industry standards, the determination of calcium and magnesium content in molybdenum concentrate adopts flame atomic absorption method. In actual production, for example, agglomeration problems often occur in the furnace of rotary kiln, affecting production. The existing detection technology has complicated steps and low detection efficiency, which affects the production progress. Therefore, it is necessary to establish an accurate and reliable method to determine the magnesium content in molybdenum concentrate to provide a basis for process indicator control and mineral resource evaluation. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for detecting the magnesium content in molybdenum concentrate, which has simple detection steps, is convenient and rapid, and has high detection accuracy.

[0004] The technical solution adopted by the present invention is:

[0005] A method for detecting magnesium content in molybdenum concentrate, comprising the following steps:

[0006] S1: Weigh 0.1-0.2g of molybdenum concentrate sample, accurate to 0.0001g;

[0007] S2: preparing a molybdenum concentrate sample solution and a molybdenum concentrate blank solution;

[0008] a. Take two identical beakers, put the molybdenum concentrate sample weighed in S1 into beaker A and moisten it with water; beaker B is an empty beaker; add nitric acid and hydrochloric acid to the two beakers respectively, cover them with a watch glass, and place them on an electric heating plate. Heat them for the first time until the sample in beaker A is completely dissolved, then take the two beakers off and cool them slightly;

[0009] b. Add hydrofluoric acid and perchloric acid to two beakers respectively, without adding a watch glass, place them on a hot plate and heat until almost dry, then remove and cool to room temperature;

[0010] c. Add 1+1 hydrochloric acid to two beakers to dissolve soluble salts, rinse the beaker wall with water and place it on a hot plate to heat and dissolve, add water to 100mL volumetric flasks after cooling, dry filter with double-layer filter paper into beakers, transfer 10mL of test solution from the two beakers, add water to 100mL volumetric flasks, and prepare molybdenum concentrate sample solution and blank solution;

[0011] S3: prepare working curve solution;

[0012] Pipette 10.00 mL of 1000 ug / mL magnesium standard stock solution into a 100 mL volumetric flask, dilute to scale with water, and mix well to obtain 1 mL of magnesium standard solution containing 100 ug magnesium.

[0013] Pipette five magnesium standard solutions in equal increments within a range of 10 mL into five 100 mL volumetric flasks, take another 100 mL empty volumetric flask, and add 10 mL of 1+1 hydrochloric acid solution to each of the six volumetric flasks, dilute to the mark with water, and mix well to obtain a set of working curve solutions;

[0014] S4: Detection;

[0015] A set of working curve solutions of S3 were placed on an inductively coupled plasma atomic emission spectrometer, and the spectral line intensity of magnesium was measured to obtain a standard working curve starting from a blank value;

[0016] The sample solution and blank solution in S2 are then placed on an inductively coupled plasma atomic emission spectrometer, the blank value is deducted, and the percentage content of magnesium in the sample solution is determined from the standard working curve.

[0017] Specifically, the two beakers in step S2 are 200-300 mL polytetrafluoroethylene beakers.

[0018] Specifically, the volume ratio of nitric acid, hydrochloric acid, hydrofluoric acid and perchloric acid added in step S2 is 10-15:5-10:3-5:3-5.

[0019] Specifically, in step S2, the first heating temperature is 220-250° C., and the heating time is 10-15 min; the second heating temperature is 270-280° C., and the heating time is 30-40 min.

[0020] Specifically, the working parameters of the inductively coupled plasma atomic emission spectrometer are: auxiliary gas flow rate 0.7-0.8 L / min, sample flow rate 1.0-5.0 mL / min, magnesium spectrum line selection 285.213, argon purity ≥99.99%.

[0021] Due to the adoption of the above-mentioned technical solution, the present invention has the following advantages:

[0022] The detection method of the present invention does not require separation, enrichment and other complicated operations in the sample pretreatment process. In the sample operation, only acid treatment is required without matrix separation. The prepared molybdenum concentrate sample solution is sucked into the instrument for determination, and the magnesium content in the sample can be displayed in real time, which greatly shortens the determination time. The method is simple to operate, has high efficiency and high sensitivity, a detection limit of 0.34 mg / L, a low determination line, a spike recovery rate of 96% to 105%, a determination range of 0.0050% to 4.28%, a wide determination range, and high precision, and is suitable for rapid detection of product quality in production. DETAILED DESCRIPTION

[0023] The present invention will be further explained below in conjunction with the embodiments, which are not intended to limit the protection scope of the present invention. The purpose of disclosing the present invention is to protect all technical improvements within the scope of the present invention. Example 1

[0024] A method for detecting magnesium content in molybdenum concentrate, comprising the following steps:

[0025] S1: Weigh 0.1g of molybdenum concentrate sample, accurate to 0.0001g;

[0026] S2: preparing a molybdenum concentrate sample solution and a molybdenum concentrate blank solution;

[0027] a. Take two 200mL polytetrafluoroethylene beakers, put the molybdenum concentrate sample weighed in S1 in beaker A, and moisten it with water; beaker B is an empty beaker; add 10mL nitric acid and 5mL hydrochloric acid to the two beakers respectively, cover them with a watch glass, and place them on a hot plate. Heat at 220℃ for 10-15min for the first time until the sample in beaker A is completely dissolved, and then take the two beakers off and cool them slightly;

[0028] b. Add 3 mL of hydrofluoric acid and 3 mL of perchloric acid to two beakers respectively, without adding a watch glass, and heat them on a hot plate at 270°C for 30-40 minutes until they are almost dry, then remove and cool to room temperature;

[0029] c. Add 1+1 hydrochloric acid to two beakers to dissolve soluble salts, rinse the beaker walls with water and heat on a hot plate to dissolve, add water to each beaker to make up to 100mL volumetric flask after cooling, dry filter with double-layer filter paper into a beaker, transfer 10mL of the test solution from each beaker to each beaker, add water to make up to 100mL volumetric flask to prepare molybdenum concentrate sample solution and blank solution.

[0030] S3: prepare working curve solution;

[0031] Pipette 10.00 mL of 1000 ug / mL magnesium standard stock solution into a 100 mL volumetric flask, dilute to scale with water, and mix well to obtain 1 mL of magnesium standard solution containing 100 ug magnesium.

[0032] Pipette 2.00 mL, 4.00 mL, 6.00 mL, 8.00 mL, and 10.00 mL of magnesium standard solution into five 100 mL volumetric flasks, take another 100 mL empty volumetric flask, and add 10 mL of 1+1 hydrochloric acid solution into each of the six volumetric flasks, dilute to the scale with water, and mix well to obtain a set of working curve solutions.

[0033] S4: Detection;

[0034] The radio frequency power of the inductively coupled plasma atomic emission spectrometer was set to 1300 W, the auxiliary gas flow rate to 0.7-0.8 L / min, the sample flow rate to 1.0-5.0 mL / min, the magnesium line to 285.213, the argon purity to ≥ 99.99%, and a set of working curve solutions of S3 were placed on the inductively coupled plasma atomic emission spectrometer, and the spectral line intensity of magnesium was measured to obtain a standard working curve starting from the blank value;

[0035] The sample solution and blank solution in S2 are placed on an inductively coupled plasma atomic emission spectrometer, the blank value is deducted, and the percentage content of magnesium in the sample solution is determined from the standard working curve.

[0036] Take two molybdenum concentrate samples and mark them as 1# molybdenum concentrate sample and 2# molybdenum concentrate sample respectively. According to the steps and methods in this embodiment, the same molybdenum concentrate sample is measured 7 times to obtain the percentage of magnesium in 1# molybdenum concentrate sample and 2# molybdenum concentrate sample as shown in Table 1 below:

[0037] Table 1 shows the results of the determination of the percentage of magnesium in molybdenum concentrate sample 1# and molybdenum concentrate sample 2#

[0038] Sample No. 1st time 2nd time 3rd 4th 5th 6th 7th average value / % RSD / % 1# 1.17 1.14 1.13 1.16 1.25 1.26 1.18 1.18 4.01 2# 3.77 3.82 3.83 3.80 3.90 3.86 3.84 3.83 1.09

[0039] It can be seen from Table 1 that the relative standard deviation RSD of the determination results is less than 5%, indicating that the detection method of the present invention has good precision and stability.

[0040] The magnesium spike recovery rates of 1# molybdenum concentrate sample and 2# molybdenum concentrate sample were determined. The sample solution in S2 was cooled and transferred into a 100 ml volumetric flask, and a certain amount of magnesium standard solution was added. The rest was analyzed according to the operating steps of this embodiment. The result measured after adding the magnesium standard solution was subtracted from the original content of the sample. The ratio of the difference to the theoretical value of the added standard substance was the spike recovery rate of the sample, that is, the spike recovery rate of magnesium = (the total magnesium content in the measured sample - the original content in the sample) ÷ the amount of magnesium standard substance added × 100%; the determination results are shown in Table 2. It can be seen from the data in Table 2 that the spike recovery rates are all above 95%, indicating that the present invention has good accuracy.

[0041] Table 2 Magnesium spike recovery of 1# molybdenum concentrate sample and 2# molybdenum concentrate sample

[0042] Sample No. Original magnesium content in molybdenum concentrate sample / mg Amount of magnesium standard solution added / mg Measured magnesium content / mg Recovery rate of magnesium spike / % 1# 1.18 2.0 3.28 103.14 2# 3.83 4.0 7.89 100.77 Example 2

[0043] A method for detecting magnesium content in molybdenum concentrate, comprising the following steps:

[0044] S1: Weigh 0.2g of molybdenum concentrate sample, accurate to 0.0001g;

[0045] S2: preparing a molybdenum concentrate sample solution and a molybdenum concentrate blank solution;

[0046] a. Take two 250mL polytetrafluoroethylene beakers, put the molybdenum concentrate sample weighed in S1 in beaker A, and moisten it with water; beaker B is an empty beaker; add 15mL nitric acid and 10mL hydrochloric acid to the two beakers respectively, cover them with a watch glass, and place them on a hot plate. Heat at 240℃ for 10-15min for the first time until the sample in beaker A is completely dissolved, and then take the two beakers off and cool them slightly;

[0047] b. Add 5 mL of hydrofluoric acid and 5 mL of perchloric acid to two beakers respectively, without adding a watch glass, and heat them on a hot plate at 280°C for 30-40 minutes until they are almost dry, then remove and cool to room temperature;

[0048] c. Add 1+1 hydrochloric acid to two beakers to dissolve soluble salts, rinse the beaker wall with water and place it on a hot plate to heat and dissolve, add water to 100mL volumetric flasks after cooling, dry filter with double-layer filter paper into beakers, transfer 10mL of test solution from the two beakers, add water to 100mL volumetric flasks, and prepare molybdenum concentrate sample solution and blank solution;

[0049] S3: prepare working curve solution;

[0050] Pipette 10.00 mL of 1000 ug / mL magnesium standard stock solution into a 100 mL volumetric flask, dilute to scale with water, and mix well to obtain 1 mL of magnesium standard solution containing 100 ug magnesium.

[0051] Pipette 1.00 mL, 3.00 mL, 5.00 mL, 7.00 mL, and 9.00 mL of magnesium standard solution into five 100 mL volumetric flasks, take another 100 mL empty volumetric flask, and add 10 mL of 1+1 hydrochloric acid solution into each of the six volumetric flasks, dilute to the mark with water, and mix well to obtain a set of working curve solutions;

[0052] S4: Detection;

[0053] The radio frequency power of the inductively coupled plasma atomic emission spectrometer was set to 1300 W, the auxiliary gas flow rate to 0.7-0.8 L / min, the sample flow rate to 1.0-5.0 mL / min, the magnesium line to 285.213, the argon purity to ≥ 99.99%, and a set of working curve solutions of S3 were placed on the inductively coupled plasma atomic emission spectrometer, and the spectral line intensity of magnesium was measured to obtain a standard working curve starting from the blank value;

[0054] The sample solution and blank solution in S2 are placed on an inductively coupled plasma atomic emission spectrometer, the blank value is deducted, and the percentage content of magnesium in the sample solution is determined from the standard working curve.

[0055] Take two molybdenum concentrate samples and mark them as 3# molybdenum concentrate sample and 4# molybdenum concentrate sample respectively. According to the steps and methods of Example 2, the same molybdenum concentrate sample is measured 7 times to obtain the percentage of magnesium in 3# molybdenum concentrate sample and 4# molybdenum concentrate sample as shown in Table 3 below:

[0056] Table 3 shows the results of the determination of the percentage of magnesium in 3# molybdenum concentrate sample and 4# molybdenum concentrate sample.

[0057] Sample No. 1st time 2nd time 3rd 4th 5th 6th 7th average value / % RSD / % 3# 0.42 0.41 0.42 0.39 0.39 0.41 0.42 0.41 3.29 4# 0.100 0.105 0.102 0.097 0.108 0.101 0.099 0.102 3.67

[0058] It can be seen from Table 3 that the relative standard deviation RSD of the measurement results is less than 5%, indicating that the present invention has good precision and stability.

[0059] Determine the magnesium addition recovery rate of 3# molybdenum concentrate sample and 4# molybdenum concentrate sample. After cooling the sample solution in step S2 and transferring it into a 100ml volumetric flask, add a certain amount of magnesium standard solution. The rest is analyzed according to the operating steps of this embodiment 2. The result measured after adding the magnesium standard solution minus the original content of the sample, and the ratio of the difference to the theoretical value of the added standard substance is the sample addition recovery rate, that is, magnesium addition recovery rate = (total magnesium content in the measured sample - original content in the sample) ÷ the amount of magnesium standard substance added × 100%. The measurement results are shown in Table 4. It can be seen from the data in Table 4 that the addition recovery rates are all above 95%, indicating that the present invention has good accuracy.

[0060] Table 4 Magnesium spike recovery of 3# molybdenum concentrate sample and 4# molybdenum concentrate sample

[0061] Sample No. Original magnesium content in molybdenum concentrate sample / mg Amount of magnesium standard solution added / mg Measured magnesium content / mg Recovery rate of magnesium spike / % 3# 0.82 1.0 1.83 100.55 4# 0.204 0.2 0.398 98.51

[0062] The parts not described in detail in this invention are prior art.

[0063] The embodiments selected herein for the purpose of disclosing the invention are currently considered to be suitable, but it should be understood that the invention is intended to include all changes and modifications of the embodiments that fall within the scope of the concept and invention.

Claims

1. A method for detecting magnesium content in molybdenum concentrate, characterized in that: The specific steps are: S1: Weigh 0.1-0.2g of molybdenum concentrate sample, accurate to 0.0001g; S2: preparing a molybdenum concentrate sample solution and a molybdenum concentrate blank solution; a. Take two identical beakers, put the molybdenum concentrate sample weighed in S1 into beaker A and moisten it with water; beaker B is an empty beaker; add nitric acid and hydrochloric acid to the two beakers respectively, cover them with a watch glass, and place them on an electric heating plate, heat them at 220-250℃ for the first time, heat for 10-15min until the sample in beaker A is completely dissolved; remove the two beakers and cool them slightly; b. Add hydrofluoric acid and perchloric acid to two beakers respectively, without adding a watch glass, and heat them on a hot plate at 270-280°C for 30-40 minutes until almost dry, then remove and cool to room temperature; The volume ratio of nitric acid, hydrochloric acid, hydrofluoric acid and perchloric acid is 10-15:5-10:3-5:3-5; c. Add 1+1 hydrochloric acid to two beakers to dissolve soluble salts, rinse the beaker wall with water and place it on a hot plate to heat and dissolve, add water to 100mL volumetric flasks after cooling, dry filter with double-layer filter paper into beakers, transfer 10mL of test solution from the two beakers, add water to 100mL volumetric flasks, and prepare molybdenum concentrate sample solution and blank solution; S3: prepare working curve solution; Pipette 10.00 mL of 1000 ug / mL magnesium standard stock solution into a 100 mL volumetric flask, dilute to scale with water, and mix well to obtain 1 mL of magnesium standard solution containing 100 ug magnesium. Pipette five magnesium standard solutions in equal increments within a range of 10 mL into five 100 mL volumetric flasks, take another 100 mL empty volumetric flask, and add 10 mL of 1+1 hydrochloric acid solution to each of the six volumetric flasks, dilute to the mark with water, and mix well to obtain a set of working curve solutions; S4: Detection; A set of working curve solutions of S3 were placed on an inductively coupled plasma atomic emission spectrometer, and the spectral line intensity of magnesium was measured to obtain a standard working curve starting from a blank value; The sample solution and blank solution in S2 are then placed on an inductively coupled plasma atomic emission spectrometer, the blank value is deducted, and the percentage of magnesium in the sample solution is determined from the standard working curve.

2. The method for detecting magnesium content in molybdenum concentrate according to claim 1, wherein: The two beakers in step S2 are 200-300 mL polytetrafluoroethylene beakers.

3. The method for detecting magnesium content in molybdenum concentrate according to claim 1, characterized in that: The working parameters of the inductively coupled plasma atomic emission spectrometer are: auxiliary gas flow rate 0.7-0.8L / min, sample flow rate 1.0-5.0mL / min, magnesium spectrum line selection 285.213, argon purity ≥99.99%.