Tanaka claims precious metals recovery breakthrough

The Tanaka Precious Metals business unit of Tokyo-based Tanaka Kikinzoku Kogyo K.K., a precious metals producer and recycler, has established a method that can recover metals including platinum and palladium that are adhere to certain types of equipment used in semiconductor manufacturing and other processes.

The new process, Tanaka Green Shield, involves cleaning nickel plating from an adhesion-preventing plate on certain components to which sputtered films can adhere. These film traces can contain platinum group metals (PGMs) that the Tanaka Green Shield process can detach from the plate.

“After detaching sputtered films adhering to components, mainly made from stainless steel, of vacuum film formation equipment such as sputtering and vacuum deposition equipment, the recovered precious metals are refined and returned to the customer with the precision-cleaned components,” the company says.

Applying a nickel plating to an adhesion-preventing plate enables PGM sputtered films to be detached through chemical treatment without damaging the base material, Tanaka adds.

According to the company, the method makes it easier than previous methods to detach PGM sputtered films. “With an anticipated reduction in recovery loss of precious metals scattered around during the grinding process, this method is also expected to achieve higher PGM recovery rates with lower costs,” Tanaka says.

The company aim to develop the Green Shield system to support a wide variety of component shapes and sizes and to expand PGM film recovery rates by six times the current level by 2025.

In recent years, the company says it has been developing a global presence in its pursuit to recover precious metals for recycling.

Currently, Tanaka operates group companies in Japan, the United States, China and Europe that combined have more than 5,300 employees and global net sales in its most recently concluded fiscal year of more than $4.6 billion.