TANAKA's Source of Competitiveness: Supporting Resource Circulation through Precious Metal Recycling

The precious metals industry has long practiced circular economy

Founded in 1885 as a money exchange under the name of "TANAKA" in Kayabacho, Tokyo, the Group has been engaged in the recycling of platinum, that is, platinum, and the domestication of industrial products from an early stage. The Group now handles the eight major precious metal elements (gold, silver, platinum group) and has more than 30 different types of products. In the industrial business, the Group provides materials for a wide range of fields, including bonding wires for semiconductors, contact materials, plating solutions, sputtering targets, platinum products for glass melting, fuel cell catalysts, and medical materials.

Among these, the precious metals recycling business, which has been in operation since the Company's founding, is attracting attention from the perspective of resource circulation. This is what Mr. Shigetaka Kanemitsu of the Sales Division has to say.

“Long before environmental issues became a topic of discussion, recycling has been embedded in our DNA as an absolute requirement for the industry. The question is how to make effective use of limited materials. The precious metals industry has, from the past, been one that can only exist with a circular economy.”

For TANAKA, recycling is not merely a matter of “considering the environment.” It is at the core of its business, supporting material procurement, technology development, product supply, and relationships with customers.

Recycling is part of TANAKA's business

The Company handles all precious metal materials, including gold and silver, but particularly those of the platinum group—namely platinum, palladium, rhodium, iridium, and ruthenium—about 80% of the platinum group materials handled by the Company are from recycling.

Platinum group metals are a rare resource. The amount of platinum that has been mined by humans so far is estimated to be only a few thousand tons. The industry is constantly seeking ways to recycle this precious metal. Moreover, only a few grams are said to be obtainable from 1 ton of raw ore, and mining requires large-scale excavation and transportation.

As Minoru Ogiso, General Manager of the Ichikawa and Sodegaura Plants of the Manufacturing Division, states, "Recycling is essential for using PGMs as industrial products," recycling is a practical solution to resource constraints and economic rationality.

Collection and Preprocessing

The first important step is "pre-treatment." After collecting scrap from the market, the first step called "pre-treatment" is carried out to make it easier to take representative samples for accurately analyzing the amount of precious metals contained in the scrap. Scrap is not necessarily received with precious metals uniformly contained in it. Therefore, depending on the characteristics of the scrap, pre-treatment is carried out to make it easier to achieve uniformity, such as calcination, crushing, high-frequency melting, and sometimes even acid dissolution, to melt all of the scrap.

As a prerequisite, it is necessary to select a pretreatment technology that does not cause loss of precious metals.

Assessment

Next is "evaluation." Ogiso emphasizes that "the most important thing is evaluation technology."

The technology in question here is the one used to accurately measure the types and amounts of precious metals contained in the scrap brought in. After pretreated scrap is mixed and stirred to achieve homogeneity, a sample is taken and analyzed. This sampling and analysis technology is an evaluation technology that affects the trust between the Company and its customers.

A symbolic achievement that demonstrates the company's high analytical skills is its accreditation as a "Recognized Assayer" by the LBMA ^* and LPPM ^*.

^※ LBMA is an organization that supports the international market for gold and silver, while LPPM is an organization that supports the international market for platinum and palladium. Both organizations strictly manage the quality of the bullion they issue.
^※ As of now, there are six organizations worldwide that are accredited by LPPM, and TANAKA is the only one in Japan.

Separation and Refining

This separation is said to be the most technically difficult area. Industrial products contain several platinum group metals, such as platinum, palladium, rhodium, and iridium, as alloys, and also have elements that are impurities, such as iron, copper, nickel, and chromium.

“Platinum group metals are very difficult to extract efficiently as they have similar properties. Being able to extract 100% of a single precious metal from scrap can lead to significant differences in revenue for customers. From the perspective of effectively utilizing limited resources, the role of this separation technology is also very important” (Ogiso).

Productization

The final step is "productization." After recycling, the materials entrusted by customers are refined into high-purity bullion and then follow one of three routes.

TANAKA has three methods for handling precious metals recovered from customers: purchasing them as bullion, returning them to customers as bullion, and processing and supplying them as products according to customers' needs. Among these, the overwhelming majority are cases where they are returned as products. This is because precious metals that have been recovered and refined can be returned as products according to customers' needs, thereby establishing a recycling cycle.

Mr. Kanemitsu also states, "Our strength lies in not being solely a recycling or manufacturing company." Through one-stop services, the company has achieved smoother coordination between processes, as well as stabilized and improved quality. This system aims to optimize the resource circulation of its customers' businesses while supporting the stable supply of precious metals.

Product development is linked to recycling development

For the Company, the advantage of developing unique technologies is that, due to its one-stop service, it can consider future recycling from the stage of developing new materials.

When developing a new product, a technician from the recycling division may participate in the product development division's technical meetings to proactively conduct experiments and studies on materials that may be difficult to recover in the future. Ogiso also states, "We receive samples during the development stage, allowing us to start developing recovery and refining technologies ahead of anyone else."

One of the largest recycling systems in Japan with a global presence

The Company has one of the largest recycling systems in Japan. It has different sites depending on the elements handled and the processes used: the Ichikawa and Sodegaura Plants handle platinum group metals, while the Shonan Plant handles gold and silver. In addition, it has established a system for the large-scale treatment of used automotive catalysts at Nippon PGM, a joint venture with DOWA METALMIN and KOSAKA SMELTING.

The Group is also expanding its recycling business overseas. It has established recycling-related bases and technological partnerships in China, Taiwan, Malaysia, the United States, Switzerland, and other countries, and is developing systems that allow for recycling in each region. This is in response to the stricter procedures for the movement of resources across borders due to the Basel Convention and other regulations. Even if they are valuable materials, including precious metals, they cannot be easily imported or exported if they contain harmful substances. For this reason, it has become important for customers to have a system of “local production for local consumption” that allows for recycling in each region.

The next challenge is to create new demand following automotive catalysts.

There are also challenges ahead. Used automotive catalysts account for a significant proportion of platinum group recycling. However, as the shift to electric vehicles (EVs) progresses, the demand for palladium and rhodium used in exhaust gas purification catalysts may decrease in the medium to long term.

Mr. Ogiso says, "We need to create markets that can replace those for automobiles." In particular, palladium and rhodium have a high dependence on automotive applications. If demand for catalysts were to decline due to the shift to EVs, the precious metals recovered would have nowhere to go, which would impact the entire recycling scheme.

The Potential of Precious Metals in Decarbonization, Healthcare, and Semiconductors

So, what will eventually replace the automotive market? The areas that the Company plans to focus on going forward are decarbonization, medical, and semiconductors.

In the field of decarbonization, in addition to the mass production of catalytic materials for fuel cells and precious metal catalysts for water electrolysis, we are exploring the potential of platinum group catalysts in technologies for generating methane and methanol from CO ₂ and hydrogen, and for extracting hydrogen from ammonia. In the medical field, we offer specialized precious metal materials for diagnostic kits and medical devices. In the semiconductor field, precious metal materials are used in various stages of the manufacturing process, including bonding wires, bonding materials, plating solutions, and sputtering targets.

As Mr. Ogiso states, "It is our mission to bring out the potential of precious metals," the Company intends to further explore the potential of precious metals in collaboration with a wide range of manufacturing industries.

(There was an error in the product photo caption in the magazine article. The correct information is as stated in the description on this page. We apologize for the error and any inconvenience caused.)
(Person in charge: Eiichi Matsui, Environmental Business Editorial Department, Sendenkaigi Inc.)

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