A production line for rare earth functional additives has begun operating in Baotou, the industrial hub of China's rare earth sector in the Inner Mongolia autonomous region, aiming to push the local industry into higher-value manufacturing.

Designed to produce 5,000 metric tons a year, the facility turns out additives used in polyvinyl chloride processing and flame-retardant materials. Rare earth elements improve heat resistance and durability in such products. The Baotou Research Institute of Rare Earths, which helped develop the technology, said the line offers a lower-cost and more environmentally friendly alternative to commonly used industrial additives.

Automated material dosing and packaging systems allow a small crew to manage production. "The line was built and commissioned within a year, marking the move from laboratory samples to marketable products. Its quality meets or exceeds domestic and international standards," said Cao Hongzhang, project leader.

Technical validation was completed during the laboratory stage, though earlier output was limited to small batches, said Shen Menglin, deputy director of the institute. The new line has expanded the institute's product range.

China Northern Rare Earth (Group) High-Tech, a rare earth miner and producer, partnered with the institute to build the line. Both sides say it marks the start of a broader push to expand domestic output of higher-value materials relying on rare earths.

Researchers said the pilot phase confirmed stable operation and performance, paving the way for scaling toward the planned annual capacity. Full output is expected during the 15th Five-Year Plan period (2026-30).

Local officials have highlighted the project under Baotou's industrial strategy. The city reports proven rare earth reserves of 43.5 million tons, accounting for 83.7 percent of China's total and 37.8 percent of global reserves. Its rare earth industry recorded output of 103.05 billion yuan ($14.5 billion) in 2024 as it continued expanding processing and manufacturing.

The city has upgraded smelting and related materials processing mechanisms in an effort to build a complete supply chain. Capacity for magnetic materials, polishing materials, catalytic additives and hydrogen-storage materials is approaching 300,000 tons, according to official data.

The additives project began laboratory work around 2008. Following years of downstream validation and process refinements, trial production began in August this year. The institute holds independent intellectual property rights for the process, composition and formulations.

Industry applications extend beyond specialized manufacturing. Flame-retardant materials that incorporate rare earth components are used in cable coverings, mining equipment and thermal-insulating products. "Take mine conveyor belts, for example," Shen said. "In underground coal mining, they undergo prolonged friction and can heat up and ignite. Flame retardants perform best in that scenario."

Cao said a newly produced bag of flame retardant may look ordinary but offers strong heat resistance and flame-retardant performance. The additives are already used in thermal-insulating and flame retardant formulations for new energy vehicles and robotics.

Shen added that the products bring environmental benefits by replacing some flame retardants that contain toxic substances, including arsenic.

The institute is also exploring degradable and eco-friendly materials. "PVC is not biodegradable, so biodegradable alternatives are becoming more important. There is also room for development in toughening agents," Shen said.

"Once the 5,000-ton project reaches full production, we expect healthy profit margins. We will pursue upgrades and product iterations in the future, with a particular focus on transparent products," he said.

Contact the writers at liuboqian@chinadaily.com.cn