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Metatitanic for industrial use , ammonia and various inorganic acids as raw material , has been TICl 4 , Ti (NO 3 ) 4 and Ti (SO 4 ) 2 solution , respectively, TiCl 4 , Ti (NO 3 ) 4 < / sub> and Ti (SO 4 ) 2 solution as precursor , at low temperatures and strongly acidic conditions, controlled by the hydrolysis reaction is synthesized with high surface area rutile , anatase and a mixture of the two polymorphs of nano- TiO 2 powders . Studied the hydrolysis reaction conditions on the crystalline form were studied and discussed polymorph control the synthesis reaction mechanism . Respectively SiO 2 / Al 2 O 3 and glass fiber composite oxide as the carrier , the use of liquid-phase chemical deposition method and powder sintering method SiO 2 / Al 2 O 3 composite oxide supported TiO 2 and fiberglass load TiO 2 photocatalyst . Self- assembled using a fixed bed photocatalytic reactor for both photocatalytic photocatalytic degradation were NO gas activity. Using XRD, TEM, XAFS and N 2 absorption - desorption chemical analysis the sample structure, particle morphology, particle size, crystalline phase, local structure , specific surface area and pore distribution were characterized . The results show that the temperature and the type of acid hydrolysis product of crystal on a greater impact , titanium ions are Cl - , NO 3 - exist hydrolysis in acidic solution , hydrolysis temperature <80 ℃, good crystallinity can be generated with a fine grain size of nanosized rutile TiO 2 powders , hydrolysis temperature > 80 ℃, but generates anatase TiO 2 . And there is SO 4 2 - in the presence of an acidic solution , TiO 2 crystal phase composition of the sample does not change with the change of the hydrolysis temperature changes are of anatase . Synthesized by a low temperature hydrolysis of rutile nano- TiO 2 powder specific surface area reaches 210m 2 / g to
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