Titanium recycling is focus of Japanese alliance

Asahi Kasei, Nippon Steel and Nippon Steel Trading, all based in Japan, have launched a recycling initiative with a goal to convert titanium scrap generated during the manufacturing of chlor-alkali electrolysis cells into a raw material for pure titanium.

The companies say the initiative is designed to reduce the environmental impact of cell production and enhance the value of recovered materials.

For five decades, Asahi Kasei has been involved in the chlor-alkali electrolysis industry, which produces caustic soda and chlorine. The company manufactures and supplies electrolyzer cells, ion-exchange membranes, electrodes and operational guidance for electrolysis plants.

Electrolyzers apply an electric current to split concentrated saltwater (brine) into chlorine, hydrogen, and caustic soda, which are then used in a wide variety of chemical products.

For the anode side of electrolysis cells, pure titanium is used to protect the cell from the corrosive chlorine. The metal needed requires very high purity to achieve excellent corrosion resistance and processability, say the companies.

“Therefore, when using pure titanium scrap as raw material for remelting, extremely stringent quality control and pre-treatment methods are required to prevent contamination with impurities,” according to the three companies.

To use titanium scrap and close the loop with the material value chain, Asahi Kasei has entered into a collaboration with Nippon Steel, which supplies pure titanium for electrolysis cells, and Nippon Steel Trading. The initiative will remelt the scrap generated during the cell production at Asahi Kasei’s site in Nobeoka, Japan.

To prevent contamination of the titanium scrap, Asahi Kasei says it strictly controls the entire process while maintaining traceability at its production site through digital techniques.

The material is collected by Nippon Steel Trading and processed into a state suitable for use as raw material in the remelting process. Then, a portion of the sorted and processed scrap is returned to Nippon Steel for use as raw material in its pure titanium melting process.

“The establishment of a system to circulate precious resources represents each company’s shared sustainability perspective and ongoing partnership,” says Yoshifumi Kado of Asahi Kasei’s Ion Exchange Membrane & Electrolysis System Division. “This is another valuable initiative contributing to enhanced sustainability across the entire chlor-alkali industry.”

Remarks Ken Terai of Nippon Steel, “This initiative was realized by combining Nippon Steel’s development of industrial-grade pure titanium remelting technology in its electron beam melting furnace with Asahi Kasei’s long-established management system for titanium scrap within its manufacturing process.”

Manabu Akimoto of Nippon Steel Trading comments, “This collaboration marks a significant step toward realizing a decarbonized and circular society by undertaking the recovery, processing and supply of pure titanium scrap.”