The effects of kinds and concentrations of acid and treatment time on the transformation of lithium titanate (Li2TiO3) have been studied in detail. The results show that it is easier for Li2TiO3 to turn into anatase and rutile TiO2 in hydrochloric acid medium when the same acidity of sulfuric acid and hydrochloric acid are used to treat Li2TiO3 for modification. The change of Li2TiO3 into anatase and rutile TiO2 becomes easier for the higher the concentration of sulfuric acid. In addition, more Li2TiO3 can be converted to anatase and rutile TiO2 under the longer the time of acid-treated. The sulfate radical coordinates with titanium dioxide by chelating double teeth, which is helpful for stabilizing the anatase crystalline phase. The electrophilic H+ and the high electronegative Cl- affect the Ti-O bond, resulting in the destruction of the Ti-O bond in TiO6 octahedrons, and thus promoting the structural rearrangement of anatase to rutile TiO2. From the view point that the stable structure and crystal phase of lithium ion sieve ensuring extraction lithium ion efficiently and circularly, sulfuric acid is more suitable as eluent for the preparation of lithium ion sieve than hydrochloric acid, and sulfuric acid with a low concentration is a better choice.
