Titanium dioxide being low in sulfur and super high in specific surface area as well as preparation method and purpose of titanium dioxide

The invention discloses titanium dioxide being low in sulfur and super high in specific surface area as well as a preparation method and the purpose of titanium dioxide. The preparation method comprises the processes of acidolysis, sedimentation, crystallization, filtration, concentration, hydrolysis, primary washing, bleaching, secondary washing, salt treatment, squeezing, calcining and crushing. The salt treatment process comprises the following procedures: adjusting the proportion of qualified metatitanic acid subjected to secondary washing to 250-320 g/l; putting 1000 ml of slurry into a beaker for stirring; adding ammonium hydroxide with a mass fraction of 20% to adjust the pH value of the slurry to 6-7; putting the adjusted slurry into a water bath kettle, heating to 45-50 DEG C, and carrying out heat preservation for half an hour; and subjecting 100 ml of the treated slurry to suction filtration. The preparation method disclosed by the invention has the beneficial effects that in the salt treatment pro