JP2021085682A - Lead button producing method and sample analyzing method - Google Patents

Abstract

To provide a method capable of producing a lead button with good production efficiency and a method for analyzing a sample using the same.SOLUTION: A lead button producing method includes the steps of: preparing a plurality of crucibles provided with a prepared sample containing lead oxide (II) and a flux, putting the plurality of crucibles collectively into a melting furnace, melting the sample in the plurality of crucibles put into the melting furnace, removing the plurality of crucibles in the melting furnace collectively from the melting furnace after the melting, casting the sample in the plurality of crucibles collectively removed from the melting furnace into a mold, and molding the sample after the casting to produce a lead button.SELECTED DRAWING: Figure 2

Description

The present invention relates to a method for producing a lead button and a method for analyzing a sample.

In the smelting of non-ferrous metals such as copper, there is an increasing need for technological development for recovering valuable metals, particularly precious metals such as Au, Ag, Pt, Pd, Rh, Ru and Ir. In deciding the method of recovering precious metals, it is important to understand the behavior of precious metals in the smelting process, such as investigating the physical quantity balance of precious metals from the flash smelting furnace to the electrolytic cell, but the abundance is μg / g. Until now, it has been difficult because there are many cases where the number is as low as the following.
Therefore, there is a strong demand for a highly sensitive analysis method for precious metals, and for that purpose, an analysis method with a lower limit of quantification of 0.01 g / t (0.01 μg / g) is required.

The dry assay method is known as a method for microanalyzing precious metals such as Au. In the dry assay method, the sample is mixed with lead (II) oxide and a flux, the molten sample is prepared, and then the crucible is melted to collect the noble metal in the lead mass and separate it from other sample components. Next, this lead mass is molded to produce a lead button, and lead is impregnated into a cupell (ashtray) by cupellating the lead button, and only the precious metal is taken out and then quantified (Non-Patent Document 1).

Japanese Industrial Standard M8111 "Method for quantifying gold and silver in ore"

Conventionally, in the dry assay method, the sample is melted in a crucible as described above. At this time, the crucible containing the sample is melted one by one using a crucible loading / unloading jig shaped like a fire scissors. Was thrown into. Further, after melting, the crucibles were similarly taken out from the melting furnace one by one using a crucible loading / unloading jig.

However, there are times when it is necessary to melt a large number of crucibles, such as dozens of crucibles containing the sample to be melted. If the crucible is put in and taken out one by one using the above, it takes a very long time and the manufacturing efficiency of the lead button becomes low.

Therefore, it is an object of the present embodiment to provide a method capable of producing a lead button with good production efficiency and a method for analyzing a sample using the method.

As a result of repeated researches to solve the above problems, the present inventor put a plurality of crucibles containing samples into a melting furnace at once, melted the samples in the crucibles in the melting furnace, and then in the melting furnace. It was found that the above-mentioned problems can be solved by taking out a plurality of crucibles from the melting furnace at once.

In one embodiment, the present invention completed based on the above findings is a step of preparing a plurality of crucibles provided with prepared samples containing lead (II) oxide and a melting agent, and the plurality of crucibles are collectively put into a melting furnace. The step of putting in, the step of melting the samples in the plurality of crucibles put in the melting furnace, the step of taking out the plurality of crucibles in the melting furnace at once after the melting, the step of taking out the plurality of crucibles in the melting furnace at once, and taking out from the melting furnace at once. This is a method for manufacturing a lead button, which includes a step of casting the samples in the plurality of crucibles into a mold and a step of molding the cast sample to produce a lead button.

In another embodiment of the method for manufacturing a lead button of the present invention, in the step of putting the plurality of crucibles into a melting furnace at once, the plurality of crucibles are arranged in a matrix consisting of columns and rows. A step of putting a plurality of crucibles arranged in an aligned manner into a melting furnace at least in columns or rows, and a step of taking out a plurality of crucibles in the melting furnace from the melting furnace at once is a step of taking out the plurality of crucibles in the melting furnace at once. This is a process of removing a plurality of crucibles from the melting furnace at least in columns or rows at once.

In yet another embodiment of the method for manufacturing a lead button of the present invention, in a step of arranging the plurality of crucibles in a matrix consisting of columns and rows, by arranging five or more crucibles in the columns. It is configured by arranging five or more crucibles in the row.

In yet another embodiment of the method for producing a lead button of the present invention, in the step of casting the samples in the plurality of crucibles into a mold, the plurality of crucibles taken out from the melting furnace at least in columns or rows at once. By tilting the plurality of crucibles taken out at once, the samples in the crucibles are dropped into the mold at once.

In yet another embodiment of the method for manufacturing a lead button of the present invention, the step of putting the plurality of crucibles in a melting furnace at once is a step of putting all the prepared crucibles in a melting furnace at once.

In still another embodiment of the method for producing a lead button of the present invention, the samples in the crucible are collectively dropped into a mold, and then the empty crucibles are collectively discarded.

In another embodiment of the present invention, a step of producing a bead by placing the lead button obtained by the method for producing a lead button according to the embodiment of the present invention on a cupel and blowing ash, and weighing the bead. It is a sample analysis method including a step and a step of acid-dissolving the weighed bead and then analyzing by ICP emission spectroscopic analysis method.

According to the embodiment of the present invention, it is possible to provide a method capable of producing a lead button with good production efficiency and a method for analyzing a sample using the method.

The flowchart of the lead button manufacturing method and the sample evaluation method which concerns on embodiment of this invention is shown. A schematic top view of a plurality of crucibles arranged in a matrix consisting of columns and rows on a mounting table according to an embodiment of the present invention is shown. It is a schematic diagram which shows an example of the crucible loading / unloading jig which concerns on embodiment of this invention. It is a schematic diagram which shows an example of the crucible loading / unloading jig which concerns on embodiment of this invention. It is a schematic diagram which shows an example of the crucible loading / unloading jig which concerns on embodiment of this invention. The appearance observation photograph of the cube-shaped lead button put in the cupel which concerns on embodiment of this invention is shown.

[Manufacturing method of lead button]
FIG. 1 shows a flowchart of a lead button manufacturing method and a sample evaluation method according to an embodiment of the present invention. The flowchart of FIG. 1 shows an example of the embodiment of the present invention, and is appropriately modified in accordance with JIS M8111 according to the purpose of the test, the type of the sample, the amount and state of the metal contained in the sample, and the like. You may. That is, the materials used, the implementation procedure, and the like are not limited to those described in the flowchart of FIG. 1, and each step of the flowchart of FIG. 1 is not essential, and unnecessary steps can be appropriately excluded. Further, necessary steps may be incorporated.

The method for manufacturing a lead button according to the embodiment of the present invention will be described in detail below. First, a crucible is prepared, a sample to be analyzed is placed in the crucible, and lead (II) oxide and a flux are further added. Next, the sample in the crucible, lead (II) oxide and the flux are stirred and mixed.

The sample used in the embodiment of the present invention is not particularly limited, but for example, in the smelting of ores containing valuable metals, recycled raw materials, and non-ferrous metals such as copper, valuable metals generated in the treatment process from the flash smelting furnace to the electrolytic cell can be used. Such as a sample containing. The sample may contain valuable metals, especially noble metals such as Au, Ag, Pt, Pd, Rh, Ru and Ir.

The flux used in the embodiments of the present invention includes borax, silica sand, sodium carbonate and wheat flour. For the flux, the noble metal content is estimated from the approximate sample composition, the reducing power, oxidizing power, etc. of the weighed sample are obtained, and an amount suitable for forming a predetermined amount of lead buttons from the weighed sample is prepared. To do. As the flux, for example, in addition to the above-mentioned materials, oxide ore such as manganese oxide, sulfide ore, potassium nitrate and the like can be used. Further, in the embodiment of the present invention, wheat flour is used as the reducing agent, but starch, iron material and the like can be used as the reducing agent, if necessary. The state of the reducing agent is also not particularly limited, but it is preferable to use a powder reducing agent because the step of casting a sample in a plurality of crucibles, which will be described later, into a mold becomes simpler.

In this way, after preparing a plurality of crucibles provided with the prepared sample containing lead (II) oxide and a flux, the sample in the crucible is coated with salt. Next, the plurality of crucibles are put into the melting furnace at once. The number of crucibles to be put into the melting furnace at once is not particularly limited as long as they are present, and may be, for example, 2 or more, 5 or more, 10 or more, 50 or more, or 100 or more. By putting a plurality of crucibles in a melting furnace at once, the manufacturing efficiency of lead buttons is improved. In addition, by putting multiple crucibles in the melting furnace at once, the time that the worker stays near the furnace is reduced, so the time that the worker is exposed to gas and heat is shortened, and the burden on the worker can be suppressed. it can.

In the process of putting a plurality of crucibles into a melting furnace at once, a plurality of crucibles are arranged in a column and a row, and adjacent crucibles are arranged in a matrix separated by a predetermined interval, and the plurality of crucibles arranged in an aligned manner are arranged. It is preferable that the process is to put the crucible into the melting furnace at least in columns or rows at once. It is preferable that the crucibles are arranged in the melting furnace at predetermined intervals so as to correspond to the above-mentioned alignment arrangement before charging. By arranging in this way, it becomes possible to efficiently perform the taking-out process described later. The configuration will be specifically described with reference to the drawings.

FIG. 2 shows a schematic top view of a plurality of crucibles according to an embodiment of the present invention, which are composed of columns and rows and are arranged in a matrix in which adjacent crucibles are separated by predetermined intervals. FIG. 2 shows, as an example, a mode in which a total of 100 crucibles are arranged in columns 1 to 10 and rows 1 to 10. As shown in FIG. 2, one column (10 crucibles in total) may be collectively charged into the inlet of the melting furnace. In this case, the remaining crucibles of the columns 2 to 10 (10 pieces each) are sequentially put into the inlet of the melting furnace at once. Further, the crucibles arranged in a plurality of columns (for example, a total of 20 crucibles in columns 1 and 2) may be collectively charged into the inlet of the melting furnace.

Further, one row of crucibles (10 in total) may be put into the inlet of the melting furnace at once. In this case, the remaining crucibles in the rows 2 to 10 (10 each) are sequentially put into the inlet of the melting furnace at once. Further, the crucibles arranged in a plurality of rows (for example, a total of 20 crucibles in rows 1 and 2) may be collectively charged into the inlet of the melting furnace. Further, all the crucibles arranged in alignment on the mounting table (100 crucibles in the example of FIG. 2) may be collectively charged into the inlet of the melting furnace.

In this way, a plurality of crucibles are arranged in a column and a row, and adjacent crucibles are arranged in a matrix separated by a predetermined interval, and the plurality of crucibles arranged in an arrangement are collectively arranged at least in a column or a row. By putting the crucibles in the melting furnace, it is easy to put the crucibles in, and it is possible to easily place a plurality of crucibles in the target positions in the melting furnace, and further, the time required for putting them in can be reduced.

Further, in the step of putting a plurality of crucibles into the melting furnace at once, it is preferable that the number of charging operations required to put all the prepared crucibles into the melting furnace is small. The number of charging operations required to charge all the prepared crucibles into the melting furnace is preferably 3 times or less, and preferably 2 times or less. In addition, it is most preferable to put all the prepared crucibles in a melting furnace at once (at one time). By doing so, the lead button can be manufactured with good manufacturing efficiency. In particular, when all the prepared crucibles are put in at once (at one time), it becomes easy to place the crucibles in the melting furnace while maintaining the aligned arrangement of the crucibles before putting in, and the taking-out process described later can be performed. It will be possible to do it easily.

FIG. 2 shows a mode in which a total of 100 crucibles are arranged in columns 1 to 10 and rows 1 to 10 as described above, but the present invention is not limited to this, and the number of columns is 2 or more and 5 or more. Alternatively, it may be configured by arranging 20 or more crucibles, and may be configured by arranging 2 or more, 5 or more, or 20 or more crucibles in a row.

Next, the samples in the plurality of crucibles placed in the melting furnace are melted. The melting conditions can be appropriately set depending on the composition or amount of the sample in the crucible, the number of crucibles, the desired treatment efficiency, and the like, and for example, melting can be performed at 880 to 1100 ° C. for 100 minutes.

After thawing, a plurality of crucibles in the melting furnace are collectively taken out from the melting furnace. The number of crucibles to be collectively taken out from the melting furnace is not particularly limited as long as they are present, and may be, for example, 2 or more, 5 or more, 10 or more, 50 or more, or 100 or more. By taking out a plurality of crucibles from the melting furnace at once, the manufacturing efficiency of the lead button is improved. In addition, by removing multiple crucibles from the melting furnace at once, the time that the worker stays near the furnace is reduced, so the time that the worker is exposed to gas and heat is shortened, and the burden on the worker can be suppressed. it can.

The step of collectively removing the plurality of crucibles from the melting furnace is preferably a step of collectively removing the plurality of crucibles in the melting furnace from the melting furnace at least in columns or rows. In this way, by taking out the plurality of crucibles in the melting furnace from the melting furnace at least in columns or rows at once, the crucibles can be easily taken out and the time required for taking out can be reduced.

The jigs (loading / unloading jigs) used when charging a plurality of crucibles into the melting furnace at once and when removing them from the melting furnace are not particularly limited, but for example, two crucibles as shown in FIG. A long member may be used to hold a plurality of crucibles arranged in a column so as to sandwich them for loading or unloading. Further, as shown in FIG. 4, a plurality of crucibles arranged in a row may be held so as to be sandwiched between two long members for loading or unloading. When inserting and removing a plurality of crucibles lined up in a plurality of rows or columns at once, a jig equipped with a plurality of long members can be used to collectively insert and remove a plurality of crucibles lined up in a plurality of rows or columns. Can be handled. That is, for example, if a jig having three long members is used, one row of crucibles can be sandwiched between adjacent long members, so that two rows of crucibles can be put in and taken out at once. It becomes possible to do. The distance between the long members corresponds to the predetermined distance between the plurality of crucibles arranged in alignment as described above. The shape of the long member is not particularly limited, but it is preferably a thin plate-shaped member or a rod-shaped member.

The loading / unloading jig is not limited to the one provided with the two long members shown in FIGS. 3 and 4, and for example, as shown in FIG. 5, one side has a shape that follows the outer shape of the crucible. It is composed of two members having a crucible, and when the crucible is sandwiched between the two members, the crucible may be accommodated in a space surrounded by a shape along the outer shape of each crucible.

Next, the samples in the plurality of crucibles taken out from the melting furnace at once are cast into individual molds, and the cast samples are molded into a desired shape to prepare a lead button. Here, in the process of casting the samples in the plurality of crucibles into the mold, the plurality of crucibles taken out from the melting furnace at least in columns or rows are tilted together in the crucibles. It is preferable to drop all the samples in a batch into individual molds. The production efficiency of lead buttons can be further improved by collectively performing not only charging the plurality of crucibles into the melting furnace and taking them out from the melting furnace, but also charging the plurality of crucibles into a mold for casting a sample. Here, the mold for casting the sample from each crucible is preferably arranged so as to correspond to the space between the gaps of the jig, and more preferably, the mold is provided at a space corresponding to the space between the gaps of the jig. It is preferable to use a mold having a plurality of holes. According to such a configuration, work efficiency can be further improved.

By tilting the multiple crucibles taken out at once, when dropping the samples in the crucible into the mold at once, hold the top and bottom of the crucible with a jig so that the crucible does not fall due to the tilt. , It is preferable to tilt a plurality of crucibles at once.

Alternatively, the samples in the crucible may be dropped into a mold in a batch and then the empty crucibles may be discarded in a batch. With such a configuration, the processing efficiency is better than discarding the empty crucibles one by one.

Next, a lead button is manufactured by taking out a lead mass produced by casting from a mold and molding it into a predetermined shape, for example, a cube, a rectangular parallelepiped, or a cone. The slag generated in the melting step is removed in the molding step and discarded.

[Sample analysis method]
Next, the lead button is placed on the cupel that has been placed in the furnace in advance and preheated. FIG. 6 shows an appearance observation photograph of a cube-shaped lead button placed on a cupel.

Then, ash blowing is carried out. By ash blowing, the lead button becomes molten metallic lead, which gradually becomes smaller. When taken out of the electric furnace and cooled, alloy grain beads are formed in the cupel.

Next, the beads are removed from the cupel and weighed. Next, nitric acid and hydrochloric acid are added and heat-decomposed to dissolve the acid, and then the amount of liquid is adjusted. Then, by ICP emission spectroscopic analysis (high frequency inductively coupled plasma emission spectroscopic analysis), precious metals in the sample, etc. To analyze.

Examples of the present invention will be described below, but these are provided for a better understanding of the present invention, and are not intended to limit the present invention.

A sample was prepared according to the flow shown in FIG. 1 above, and a lead button was manufactured. Specifically, as shown in FIG. 2, a plurality of crucibles containing a sample were arranged in a row of 10 crucibles and 10 crucibles in a row on a mounting table, for a total of 100 crucibles.
Next, using the crucible loading / unloading jig shown in FIG. 3, the crucibles were charged into the melting furnace 10 times in each column (10 pieces each), and the crucibles were made into 10 columns and 10 rows in the melting furnace. It was arranged in a line. After thawing, the crucibles were taken out from the melting furnace in each column (10 pieces each), and the samples in the crucibles were dropped into the corresponding molds, which was repeated 10 times in total, and all the samples were cast.
Next, the lead lumps produced by casting were taken out from the mold and molded into cube-shaped lead buttons.
As a result, it was possible to carry out the crucible in about half the man-hours as compared with the conventional method in which the crucibles were put into the melting furnace one by one and taken out one by one.

In this embodiment, the method of performing the test by ICP emission spectroscopy using the beads of alloy particles has been described, but the test can also be performed using other analysis methods. For example, the test is performed by the fractionation method. You may go.

Claims (7)

Step of preparing multiple crucibles with prepared samples containing lead (II) oxide and flux,
The process of putting the plurality of crucibles into the melting furnace at once,
A step of melting a sample in a plurality of crucibles placed in the melting furnace,
After the melting, a step of taking out a plurality of crucibles in the melting furnace from the melting furnace at once,
The step of casting the samples in the plurality of crucibles collectively taken out from the melting furnace into a mold, and
A method for manufacturing a lead button, which comprises a step of molding a sample after casting to produce a lead button. In the step of putting the plurality of crucibles into the melting furnace at once, the plurality of crucibles are arranged in a matrix consisting of columns and rows, and the plurality of crucibles arranged in the arrangement are collectively arranged at least in columns or rows. It is a process of putting it in a melting furnace.
The step of collectively taking out a plurality of crucibles in the melting furnace from the melting furnace is a step of collectively taking out the plurality of crucibles in the melting furnace from the melting furnace at least in columns or rows. How to make a lead button. In the step of arranging the plurality of crucibles in a matrix consisting of columns and rows, the columns are configured by arranging 5 or more crucibles, and the rows are configured by arranging 5 or more crucibles. The method for manufacturing a lead button according to claim 2. In the step of casting the samples in the plurality of crucibles into a mold, the plurality of crucibles taken out from the melting furnace at least in columns or rows are tilted together with the plurality of crucibles taken out, thereby causing the crucibles. The method for producing a lead button according to claim 2 or 3, wherein the samples in the crucible are dropped into a mold in a batch. The method for manufacturing a lead button according to any one of claims 1 to 4, wherein the step of collectively putting the plurality of crucibles into the melting furnace is a step of putting all the prepared crucibles into the melting furnace at once. The method for producing a lead button according to any one of claims 1 to 5, wherein the samples in the crucible are collectively dropped into a mold, and then the empty crucibles are collectively discarded. A step of producing a bead by placing the lead button obtained by the method for producing a lead button according to any one of claims 1 to 6 on a cupel and blowing ash.
The process of weighing the beads and
A method for analyzing a sample, which comprises a step of acid-dissolving the weighed bead and then analyzing it by ICP emission spectroscopy.

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