The process used to extract titanium is called the Kroll process and is named after William J. Kroll, who invented the method in the 1930s. It is slow and has at least two steps. First the titanium oxide ore is reacted with chlorine to make titanium chloride. 1. Balance this equation to show the reaction between titanium oxide and chlorine: TiO 2 + Cl 2 TiCl 4