2019 has been declared by UNESCO as the Year of the Periodic Table. To celebrate, we are releasing a series of blogs about our favourite elements and their importance to the chemical industry. Today’s blog focuses on tungsten.
History
Over three centuries ago, this metal was first used by porcelain makers in China. They used a tungsten pigment to incorporate a peach colour into their art work. In 1781, Wilhelm Scheele examined a metal containing tungsten and successfully isolated an acidic white oxide, deducing the oxide of the new metal. In 1783, Wilhelm’s brothers produced the same acidic metal oxide, and upon heating it with carbon, they successfully reduced it to tungsten.
Health concerns
Tungsten raises concerns regarding the health effects associated with its levels of toxicity. Initially, tungsten was perceived to be immobile in the environment and therefore used as a viable replacement for lead and uranium in military applications. However, reports showed traces of tungsten detected in soil and potable water sources, increasing the risk to human exposure. According to public health reports, it is unlikely that tungsten present in consumer products poses a hazard or causes any long-term health effects. Therefore, further assessment on the potential long-term health effects of tungsten exposure is still required.
Properties
Tungsten is a refractory metal and as it has the highest melting temperature of all metals, it is used across a range of applications. Tungsten is alloyed with other metals to strengthen them. This makes them useful to many high-temperature applications, including arc-welding electrodes.
Properties
Tungsten is a refractory metal and as it has the highest melting temperature of all metals, it is used across a range of applications. Tungsten is alloyed with other metals to strengthen them. This makes them useful to many high-temperature applications, including arc-welding electrodes.
It is used as a novel material for glass parts due to its superior thermochemical stability. As it is a good electric conductor, it is also used in solar energy devices. Tungsten compounds act as catalysts for energy converting reactions, leading many manufacturers to investigate further uses of tungsten.
