MELBOURNE - Natrium Redox Technologies, a green technology startup based in Britain, said on Monday it had made a firm proposal to the Tasmanian government to acquire and restart Australia's only manganese smelter, to supply global battery and electric vehicle markets.

EY Parthenon said last month the Liberty Bell Bay (LBB) Smelter would close after a proposed sale fell through. The smelter, formerly owned by British industrialist Sanjeev Gupta's GFG Alliance, entered voluntary administration in March and liquidation this month after suspending operations mid-last year.

"We have engaged with EY Parthenon and the Tasmanian government on this proposal for six months. We have also briefed the federal government," Natrium Redox Technologies said in a statement.

"Our restart proposal seeks shared input of funds with government to the level of A$15-million ($10.75-million) for a 16-week restart period and a continuation of the existing electricity contract."

In a statement, Tasmanian Business Minister Felix Ellis said potential pathways for the site had been put forward, but no transaction has been completed and no commitments were made.

"EY currently controls the site as liquidator, which includes decisions about its sale," he said. EY Parthenon had no immediate comment.

Natrium Redox Technologies said it planned initially to use conventional smelting techniques to restart the smelter before building a pilot plant that would use new technology to produce high-purity, low-emissions manganese powder.

The process uses liquid sodium in place of coking coal to strip oxygen from manganese ore. It operates at lower temperatures than traditional smelting and does not produce carbon emissions.

The new technology would add 20% to 40% to the site's production and lift the smelter up the value chain from being a conventional alloy smelter into one of the highest-value manganese operations in the world by producing battery-grade materials, the company said.

"Battery grade materials sell for a far higher price than conventional alloys, securing LBB’s financial future and ensuring it remains a strategically important critical minerals asset for Australia."

Its proposal would provide more than 200 jobs previously linked with the smelter, as well as secure others during construction, Natrium Redox Technologies said.

It also has a proposal to reprocess a A$210-million environmental liability that has accumulated from decades of slag and waste, removing environmental liabilities from the government, it said.

The company emphasised that time was of the essence because the longer furnaces are idled, the harder and more expensive a restart would become.