摘要
TiO_2 visible light catalysts with different crystalline phases and morphologies were synthesized from titanium-bearing electric arc furnace molten slag(Ti-bearing EAF slag)by using a simple acidolysis process.The effects of the p H of the HCl solution,liquid to solid ratio(RL/S,HCl solution to the residue ratio,m L/g) and acidolysis time on the micro-morphology and crystalline phase of as-prepared TiO_2 photocatalysts were systematically investigated.The results indicated that with decreasing p H in the HCl solution and increasing RL/S,the crystalline phase and micro-morphology of the obtained TiO_2 nanostructures tended to transform from anatase type TiO_2 with spherical nanoparticle structures to rutile type TiO_2 with needle-like nanorod structures.The acidolysis time had little influence on the crystalline phase but great impact on the size of the obtained TiO_2.The growth mechanism of TiO_2 from Ti-bearing EAF slag during the acidolysis process was also discussed.In addition,the influence of RL/Son the photocatalytic properties of the synthesized nanostructured TiO_2 was studied.The results showed that the photodegradation efficiency for Rhodamine B solution could reach 91.00% in 120 min when the RL/Swas controlled at 50:1.
TiO_2 visible light catalysts with different crystalline phases and morphologies were synthesized from titanium-bearing electric arc furnace molten slag(Ti-bearing EAF slag)by using a simple acidolysis process.The effects of the p H of the HCl solution,liquid to solid ratio(RL/S,HCl solution to the residue ratio,m L/g) and acidolysis time on the micro-morphology and crystalline phase of as-prepared TiO_2 photocatalysts were systematically investigated.The results indicated that with decreasing p H in the HCl solution and increasing RL/S,the crystalline phase and micro-morphology of the obtained TiO_2 nanostructures tended to transform from anatase type TiO_2 with spherical nanoparticle structures to rutile type TiO_2 with needle-like nanorod structures.The acidolysis time had little influence on the crystalline phase but great impact on the size of the obtained TiO_2.The growth mechanism of TiO_2 from Ti-bearing EAF slag during the acidolysis process was also discussed.In addition,the influence of RL/Son the photocatalytic properties of the synthesized nanostructured TiO_2 was studied.The results showed that the photodegradation efficiency for Rhodamine B solution could reach 91.00% in 120 min when the RL/Swas controlled at 50:1.
基金
supported by the National Basic Research Program of China(Nos.2014CB643401,2013AA032003)
the National Nature Science Foundation of China(Nos.51372019,51277025 and 51072022)