A process used for producing synthetic rutile (titanium dioxide) as a titanium concentrate from ilmenite ore. The ore contains largely rutile and the process removes iron oxide impurity by roasting with sulphur at 1,200°C in a rotary kiln. The iron is reduced to metal and removed by magnetic separation along with coal and ash. The reduced ilmenite is washed in water containing ammonium chloride as a catalyst and air blown through to convert metallic iron to a flocculent precipitate of iron oxides. These are then removed. The process was invented by Robert Gordon Becher in the 1960s.