KR100528506B1 - A Method for Concentrating and Recovering Precious Metals from Spent PCBs and Spent Auto-Catalysts Simultaneously - Google Patents

Abstract

The present invention relates to a method for simultaneously recovering precious metals from waste printed circuit boards and waste catalysts.

In particular, the solvent and the reducing agent are added to the waste printed circuit board and the waste catalyst, followed by high temperature melting to reduce the copper, tin, and iron contained in the waste printed circuit board, and the waste printed circuit to the fish copper, tin, and iron alloy. It is characterized in that the concentrated recovery of gold, platinum, palladium contained in the substrate and spent catalyst for automobiles.

Accordingly, different industrial wastes are treated to concentrate the recovery of precious metals such as gold, platinum, and palladium, and to recycle resources by waste.

Description

A Method for Concentrating and Recovering Precious Metals from Spent PCBs and Spent Auto-Catalysts Simultaneously}

The present invention relates to a method for simultaneously concentrating and recovering precious metals from waste printed circuit boards and waste catalysts. The present invention relates specifically to solvents and reducing agents in waste printed circuit boards discharged from waste electricity and electronic devices and waste catalysts for automobiles discharged from waste vehicles. By mixing and melting at high temperature to collect and concentrate precious metals such as gold, platinum and palladium contained in the waste printed circuit board and waste catalyst in metal components such as copper, tin and iron in the waste printed circuit board. The present invention relates to a method for recovering precious metals from waste printed circuit boards and waste catalysts that are simultaneously recovered.

In general, printed circuit boards mounted on electric and electronic devices such as personal computers and the like contain valuable metals such as copper, tin, and iron, as well as precious metals such as gold, silver, and palladium.

The amount of precious metals to be recovered depends on the type of electric and electronic devices and the production year. However, the amount of precious metals is about 200-700g / T for gold, 50-150g / T for palladium and 5-15% for copper. Known.

Also, precious metals used as catalysts for automobile exhaust gas purification are platinum, palladium, rhodium, etc., which are distributed at a constant rate as fine particles on the surface of the honeycomb carrier and contain platinum, palladium, rhodium, etc. at the time of disposal. Spent catalysts are produced, and their contents vary slightly depending on the manufacturer, type of car, and the year of production, but they contain approximately 900 to 2000 g / T.

On the other hand, with the development of the domestic industry, the generation of industrial wastes such as waste printed circuit boards and automobile waste catalysts is rapidly increasing, and environmental pollution is a social problem.

However, precious metals contained in wastes such as waste printed circuit boards and waste catalysts are not only very important positions as raw materials for high-tech industries, but also have high added value at a high price. It can be said that it is required to be recovered in terms of resource recycling, which is a national economic demand. By recovering and recycling it, it can be said that it is very useful in terms of reducing the cost of catalyst as well as the effective use of resources.

The recovery of precious metals from industrial wastes such as waste printed circuit boards and automotive waste catalysts is largely classified into a dry method and a wet method.

The double wet method is a method of directly leaching and recovering waste printed circuit boards and waste catalysts from automobiles with aqua regia or hydrochloric acid solution, resulting in excessive waste water and difficulty in treating residue after recovery of precious metals. It is difficult to apply to waste printed circuit boards and waste catalysts for automobiles.

On the other hand, the dry method is a method of recovering a noble metal by adding a solvent and a reducing agent to industrial waste and then melting at a high temperature, whereby the noble metal is concentrated and recovered in a trapped metal such as copper, lead, or iron, which is introduced with the solvent. There is no generation of waste water, and the generated slag has an advantage of high recycling rate because there is almost no environmental problem.

However, in order to recover precious metals from industrial wastes in Korea, it is difficult to secure economic feasibility due to the small amount of waste generated, and to collect precious metals such as solvent and copper when recovering precious metals from industrial wastes by dry method. There is a disadvantage that the recovery rate is lower than the wet method.

An object of the present invention for improving this is to treat different industrial wastes such as waste printed circuit boards and waste catalysts for automobiles containing precious metals and to recover the precious metals such as gold, platinum, and palladium, and to recover the resources by waste. The present invention provides a method for simultaneously concentrating and recovering precious metals from waste printed circuit boards and waste catalysts to enable recycling of wastewater.

In addition, by using metal components such as copper, tin, and iron contained in the waste printed circuit board without adding the collecting metal separately, and reducing the amount of solvent added for slag formation by using the carrier component of the automotive waste catalyst. The present invention provides a method for simultaneously recovering precious metals from waste printed circuit boards and waste catalysts.

In order to achieve the above objects, the waste printed circuit board and the waste catalyst for automobiles are pulverized and mixed, followed by mixing carbon as a reducing agent, alumina as a solvent, lime, magnesium, iron oxide, and silica in an appropriate ratio, and melting them at a high temperature to waste. There is provided a method for simultaneously collecting and recovering precious metals from a waste printed circuit board and a waste catalyst which concentrates and recovers the precious metals in metal components such as copper, tin, and iron contained in the printed circuit board.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in Figures 1 and 2, the present invention, the waste printed circuit board obtained by dismantling waste electrical and electronic products, such as waste printed circuit boards generated in Korea, shredded to a size 1 cm or less as a shredder, and then burned Volatile organic components such as epoxy and resin, which are the main components of the closed printed circuit board, are volatilized and removed.

Then, the waste catalyst for automobiles discharged at the time of scrapping is shredded with a cutter or the like to have a particle size of 1 cm or less.

Subsequently, a predetermined amount of the waste printed circuit board combusted after crushing and a waste catalyst for crushed automobile are taken, and then a solvent and a reducing agent are added thereto and mixed uniformly.

At this time, the solvent is added to form a slag, alumina (Al ₂ O ₃ ) -lime (CaO)-magnesia (MgO)-silica (SiO ₂ ) slag system,

Any one selected from quicklime (CaO) -iron oxide (FeO) -silica (SiO ₂ ) slag system is used.

When the alumina (Al ₂ O ₃ ) -lime (CaO) -magnesia (MgO) -silica (SiO ₂ ) slag system is added as a solvent, the input ratio of the waste printed circuit board, the waste catalyst, the reducing agent and the solvent is 40 to 70% by weight of the printed circuit board, 10 to 25% by weight of waste catalyst, 3 to 6% by weight of magnesia as solvent, 1 to 3% by weight of alumina, 3 to 16% by weight of quicklime, 2 to 20% by weight of silica, and reducing agent 7-11% by weight of carbon is added and mixed, and the mixture is melted for 1 hour or more at a temperature of 1300-1400 ° C.

In addition, when quicklime (CaO) -iron oxide (FeO) -silica (SiO ₂ ) slag is added as a solvent, the input ratio of the waste printed circuit board, the waste catalyst, the reducing agent and the solvent is 20-30 weight of the waste printed circuit board. %, 5-15 wt% of spent catalyst, 15-20 wt% of quicklime as a solvent, 10-20 wt% of silica, 25-35 wt% of iron oxide, and 3-5 wt% of carbon as a reducing agent are mixed and mixed. Melt at 1300 ~ 1400 ℃ in electric furnace for over 1 hour.

In addition, carbon (C) introduced into the reducing agent is added to prevent the reduction and reoxidation of metal components in the waste printed circuit board.

In addition, the raw material melted in the electric furnace is discharged by forcibly cooling to a temperature of 800 ℃ in the furnace, and the discharged raw material is in the solidified alloy state and slag phase, and the alloy component is separated to recover the precious metal .

When explaining the present invention in more detail as follows.

As shown in Figures 1 and 2, a sample in which a waste printed circuit board, a vehicle waste catalyst, a solvent, a reducing agent and the like are uniformly mixed at an appropriate ratio is introduced into the crucible, and the crucible is charged into an electric furnace and then 1,300-. It melts at 1,400 ℃ for 60 ~ 180 minutes to concentrate precious metals such as gold, platinum and palladium contained in waste printed circuit boards and automotive waste catalysts from metal components such as copper, tin and iron of waste printed circuit boards.

Then, the crucible containing the melt consisting of a metal component and slag enriched in precious metals as described above is forced to cool to 800 ℃ in an electric furnace, and the crucible is discharged to separate the solidified metal component and slag, and the concentrated metal component Purify and recover precious metals from

If the cooling temperature in the furnace is more than 800 ℃ or less it is difficult to separate the slag and metal components.

At this time, after separating the metal component and slag, the gold, platinum, palladium and the like are purified and recovered from the concentrated metal component of the precious metal, and the slag from which the precious metal is recovered can be reused for recovery of other precious metal or used as a raw material of cement.

Example 1

Alumina (Al ₂ 0 ₃ ) -lime (CaO) -magnesia (MgO) -silica (SiO ₂ ) -based solvents using carbon as a reducing agent, the addition amount and recovery for each sample are shown in Table 1.

First, the waste printed circuit board and the automotive waste catalyst are crushed to 1 cm or less, and 100 g of the crushed waste printed circuit board is removed to remove volatile organic components from the waste printed circuit board, and incinerated at 700 ° C. for about 60 minutes.

Then, 62 g of the incinerated waste printed circuit board was mixed with 26.6 g of automobile waste catalyst, 19.6 g of quicklime with solvent, 2.8 g of silica, 4.6 g of magnesia, and 10 g of carbon with a reducing agent, which was charged into a crucible and charged into an electric furnace. Melt for 60 minutes at 1350 ° C.

Subsequently, when melting is completed, the crucible is cooled to 800 ° C. in an electric furnace and then the crucible is discharged. At this time, the solidified metal alloy phase and the slag are separated to recover the metal alloy phase in which the precious metal is concentrated.

Table 1

division Addition amount (g) % Recovery Burnt Waste Printed Circuit Board Automobile Waste Catalyst MgO Al ₂ O ₃ SiO ₂ CaO carbon Au Pt Pd One 62 12.0 5.22 2.47 0 13.58 10 99.9 99.8 97.9 2 62 17.4 4.35 1.15 0 15.16 10 99.7 97.9 99.6 3 62 26.6 4.64 0 2.82 19.58 10 99.7 97.8 96.7 4 62 12.0 4.39 0 5.12 3.39 10 99.4 93.3 92.5 5 62 17.4 5.22 0 11.52 5.72 10 99.8 97.1 93.2 6 62 26.6 6.93 0 26.80 9.91 10 94.2 93.7 91.7

As a result, the amount of precious metal contained in 100g of waste printed circuit board and 26.6g of automobile waste catalyst was 332g / T of gold, 378g / T of platinum, and 252g / T of palladium. The precious metals present were 25.9 mg of gold, 46.8 mg of platinum, and 36.7 mg of palladium. 99.7% of gold, 97.8% of platinum, and 96.7% of palladium were recovered.

At this time, the addition ratio of each sample of the precious metal recovery method in which alumina (Al ₂ O ₃ ) -lime (CaO) -magnesia (MgO) -silica (SiO ₂ ) slag is added as a solvent is shown in Table 2.

 [Table 2]

division Addition ratio (%) Burnt Waste Printed Circuit Board Automobile Waste Catalyst MgO Al ₂ O ₃ SiO ₂ CaO carbon One 58.9 11.4 5.0 2.3 0 12.9 9.5 2 56.3 15.8 4.0 1.0 0 13.8 9.1 3 49.3 21.2 3.7 0 2.2 15.6 8.0 4 64.0 12.4 4.5 0 5.3 3.5 10.3 5 55.4 15.6 4.7 0 10.3 5.1 8.9 6 43.6 18.7 4.9 0 18.8 7.0 7.0

Example 2

The quicklime (CaO) -iron oxide (FeO) -silica (SiO ₂ ) system is used as a solvent and carbon is used as a reducing agent. The addition amount and recovery rate of each sample are shown in Table 3.

The waste printed circuit board discharged from the waste cell phones and the waste catalyst for automobiles discharged from the abandoned vehicle are ground to 1 cm or less.

Subsequently, in order to remove volatile organic components from the waste printed circuit board, 112.9 g of the ground waste printed circuit board was taken and incinerated at 700 ° C. for about 120 minutes.

Then, 70 g of the waste printed circuit board incinerated after crushing was mixed with 30 g of automobile waste catalyst, 54 g of quicklime (CaO) with solvent, 46 g of silica (SiO ₂ ), 90 g of iron oxide (FeO), and 11.3 g of carbon with a reducing agent. It is charged into an electric furnace and melted for 60 minutes at 1350 ℃.

Subsequently, when melting is completed, the crucible is cooled to 800 ° C. in an electric furnace, and then the crucible is discharged. The solidified metal alloy phase and the slag are separated to recover the metal alloy phase in which the precious metal is concentrated.

Table 3

division Addition amount (g) % Recovery Burnt Waste Printed Circuit Board Automobile Waste Catalyst FeO SiO ₂ CaO carbon Au Pt Pd One 80 20 91 43.1 53.9 12.9 99.6 99.7 97.7 2 70 30 90 46 54 11.3 99.8 97.9 99.0

As a result, the precious metals contained in 112.9g of waste printed circuit board and 30g of automobile waste catalyst were 332g / T of gold, 378g / T of platinum and 353g / T of palladium. The precious metals present were 29.3 mg of gold, 43.0 mg of platinum, and 56.1 mg of palladium. 99.8% of gold, 97.9% of platinum, and 99.0% of palladium were recovered.

At this time, the addition ratio of each sample of the precious metal recovery method in which the quicklime (CaO) -iron oxide (FeO) -silica (SiO ₂ ) slag is added as a solvent is shown in Table 4.

Table 4

division Addition ratio (%) Burnt Waste Printed Circuit Board Automobile Waste Catalyst FeO SiO ₂ CaO carbon One 26.6 6.6 30.2 14.3 17.9 4.3 2 23.2 10.0 29.9 15.3 17.9 3.8

As described above, in the waste printed circuit boards discharged from electric and electronic products including waste PCs generated in Korea, and in the waste catalysts for automobiles discharged when the automobiles are discarded, reducing agent carbon (C) and alumina (Al ₂ O ₃ ) as a solvent ) -Lime (CaO) -Magnesia (MgO) -Silica (SiO ₂ ) slag and quicklime (CaO) -Iron oxide (FeO) -Silica (SiO ₂ ) slag are mixed and melted at high temperature In this case, the slag generated after recovering the precious metal is to be used for recovery of other metals and reuse as a cement raw material.

As described above, according to the present invention, by using metal components including copper, tin, and iron contained in the waste printed circuit board as the collecting metal, additional addition of the collecting metal for recovering the precious metal from the waste printed circuit board and the automobile waste catalyst is necessary. There is no effect of reducing the amount of solvent input for slag formation by utilizing the cordierite component of silica and automobile waste catalyst contained in the waste printed circuit board as a solvent.

In addition, it is an energy-saving environment-friendly technology that recovers more than 95% of precious metals such as gold, platinum, and palladium contained in waste printed circuit boards and waste catalysts at the same time, and reuses slag to recycle resources by simultaneously recovering precious metals from different wastes. It is.

While the invention has been shown and described with respect to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit or scope of the invention as provided by the following claims. I would like to clarify that those who have knowledge of this can easily know.

1 is a block diagram showing a precious metal and slag recovery process according to the present invention.

Figure 2 is a flow chart showing the inner ear and slag recovery process according to the present invention.

Claims (6)

Shredding the waste printed circuit board and the waste catalyst to 1 cm or less, respectively, and mixing them, wherein the waste printed circuit board is crushed to remove volatile organic components, followed by melting at 700 ° C. for 60 minutes to mix; Adding a reducing agent and a solvent to the mixed waste printed circuit board and the waste catalyst to be mixed, and melting them at high temperature; Cooling the raw material to be melted in a furnace to a predetermined temperature and then discharging it; Separating the solidified concentrated metal component and slag from the discharged raw material; And, Simultaneous recovery of precious metals from the waste printed circuit board and the waste catalyst comprising the step of purifying and recovering the precious metal from the metal component. delete The method of claim 1, wherein the mixing of the waste printed circuit board and the waste catalyst by adding a reducing agent and a solvent and melting the same at high temperature comprises using carbon as a reducing agent and alumina-lime-magnesia-silica slag-based solvent. And, a method for simultaneously recovering precious metals from waste printed circuit boards and waste catalysts, using any one selected from quicklime-iron oxide-silica slag systems. The method of claim 1 or 3, wherein the step of mixing the waste printed circuit board and the waste catalyst by adding a reducing agent and a solvent and melting them at high temperature comprises: a) 40 to 70 wt% of the waste printed circuit board, b) waste catalyst 10-25% by weight, c) 3-6% by weight of magnesia, 1-3% by weight of alumina, 3-16% by weight of quicklime, 2-20% by weight of silica, d) and 7-11% by weight of carbon by reducing agent Simultaneous recovery of precious metals from a waste printed circuit board and waste catalyst, characterized in that the mixture, and melted for 1 hour or more at a temperature of 1300 ~ 1400 ℃. According to claim 1 or 3, wherein the step of mixing the reducing printed circuit board and the waste catalyst by adding a reducing agent and a solvent and the high temperature melting, a) 20 to 30% by weight of the waste printed circuit board, b) waste catalyst 5 to 15% by weight, c) 15 to 20% by weight of quicklime, 10 to 20% by weight of silica, 25 to 35% by weight of iron oxide, d) and 3 to 5% by weight of carbon as a reducing agent. Simultaneous recovery of precious metals from waste printed circuit boards and waste catalysts, characterized in that melting for 1 hour or more in an electric furnace at a temperature of 1400 ℃. The method of claim 1, wherein the step of discharging the molten raw material after cooling to a predetermined temperature in the furnace, the discharge of the waste printed circuit board and the precious metal from the waste catalyst, characterized in that the discharge after cooling to 800 ℃ in the furnace Concentrate recovery method.