Abstract
Titanium is one of the most abundant metals with superior properties such
as excellent mechanical properties, high strength-to-weight ratio, and oxidation and corrosion
resistance. However, it is commercially expensive to produce; hence, its use is
limited. Currently, the Kroll process remains the most commercially exploited to produce
titanium. Therefore, this paper thoroughly reviews some other proposed and developing
thermo-reduction methods using the two main precursors titanium dioxide (TiO2) and
titanium chloride (TiCl4) together with the environmental impacts they cause. The exorbitant
production cost and environmental issues have resulted in enormous research and
development to innovate more sustainable methods of titanium production. The various
processes were comprehensively analyzed to assess whether they have the potential to
expand to be economically viable. From this review, it is apparent that most of the methods
still require further research to scale them up to an industrial and commercial level. Recent
developments including the Council for Scientific and Industrial Research-Ti (CSIR-Ti), Titanium
Reduction Oxide (TiRO), Preform Reduction Process (PRP), and hydrogen-assisted
magnesiothermic reduction (HAMR) processes are auspicious for producing high-purity
titanium sustainably.