Preparation of titanium dioxide from titania-rich slag by molten NaOH method

Yan-fang Han1,2,3),Ti-chang Sun1),Jie Li2,3),Tao Qi2,3),Li-na Wang2,3),and Jing-kui Qu2,3) 1) School of Civil and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China 2) National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China3) Key Laboratory of Green Process and Engineering,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China

摘 要：Preparing titanium dioxide from titania-rich slag（TiO2 73wt%） by molten NaOH method has been developed.The effects of tem-perature and reaction time on the titanium conversion were investigated.The results showed that temperature had significant influence on the titanium conversion as well as the structure of the product.About 92% of titanium in the titania-rich slag could be converted after reacting with NaOH at 500℃ for 1 h.Metatitanic acid was formed through the steps of washing treatment,acid dissolution,and hydrolysis.Well-dispersed spherical titanium dioxide particles with an average size of 0.1-0.4 μm can be obtained by calcination of metatitanic acid.In addition,the content of titanium dioxide in the product is up to 98.6wt%,which can be used as pigments after further treatment of coating and crushing.

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