Titanium Powder, Alloys By Electrolysis

The financial press has just released information about a new industrial development prospect, described as a process that allows the reduction of high-melting-point metal ores such as titanium, tantalum, and potentially other expensive metallic elements including neodymium, tungsten and vanadium, from the oxide to the metal in powder form.

The process is a type of electrolysis, but rather than hold the metal oxides in liquid form, it holds them as metal powders in a liquid salt at much lower temperatures and hence requires much lower energy inputs than would be the case if they were reduced in the liquid state.
The process starts with powdered metal oxide, which serves as the cathode. The anode is made of carbon, and the molten salt (which has a temperature of 1,000°C) acts as an electrolyte, permitting current, in the form of oxygen ions, to pass from cathode to anode.There, the ions react to form carbon dioxide, while the cathode is gradually transformed from oxide to metaln.

The current first industrial-size trial is aiming at the 2,500-ton/year tantalum market; the next stage will be the far greater prize of making inroads into the 140,000-ton titanium market. Titanium has potentially many more uses if the unit price was lower. It is believed 3D additive manufacturing probably offers the best route to exploiting new uses for the titanium powders produced.

The firm developing the technology is called Metalysis, a spin-off from Cambridge University where the initial research was carried out. Stepping back from the initial enthusiasm for any new metals technology, though one has to ask how far the technology is likely to go in a high electricity priced market like the UK.

Certainly as a percentage of the finished metal price, the power consumption of Metalysis titanium powder is likely to be much less than the power component in, say, aluminum, which also uses an electrolytic process, and where the power component is reckoned to be up to a third of the approximately $2,100/ton production cost of primary aluminum.

by Stuart Burns