Article published in Aluminium International Today
Aluminium oxide (Al2O3), better known as alumina, has been produced in Australia for more than fifty years and is largely supplied to the global aluminium smelting industry as metallurgical grade alumina, usually at purities of more than 99%. Australia is the world’s second largest producer and world’s largest exporter of metallurgical grade alumina, producing more than 21 Mt per annum. Alumina refineries can also produce alumina for a range of non-metallurgical uses, including water treatment; production of aluminium fluoride; ceramics, refractories and abrasives.
However, there has been an emergence in demand for very high purity alumina’s. Known as just that – High Purity Alumina (HPA) – the products range in purity of more than 99.99% (4N) through to purities of more than 99.9999% (6N). While the difference between 99% (known as 2N) and 4N may be subtle, it has a profound impact on everyday items in our lives.