利用化学沉淀法制备CaCO₃/TiO₂复合粒子,直接将CaCO₃加入水中配制CaCO₃浆料,再将事先配制好的钛酸四丁酯前驱体溶液滴加到CaCO₃浆料中,水解成核生长,得到CaCO₃/TiO₂复合粒子。结果表明:CaCO₃/TiO₂复合粒子表面粗糙,存在大量、排列致密的,粒径约为5～8nm的TiO₂微粒;当CaCO₃浆液浓度为10g/L,配制的钛酸四丁酯溶胶发生部分水解反应[n(H₂O):n(Ti(OC₄H₉)₄)=2:1],CaCO₃与TiO₂质量比为1g:0.75g时,反应2h条件下得到的复合粒子在邻苯二甲酸氢钾-氢氧化钠缓冲溶液中溶出的Ca²⁺浓度最小,耐酸性能最好。

The chemical precipitation method was used to prepare CaCO₃/TiO₂ composite particles.Calcium carbonate was directly added to water to prepare a calcium carbonate slurry,and the previously prepared tetrabutyl titanate precursor solution was added dropwise to the calcium carbonate slurry.In the process,hydrolysis and nucleation grown to obtain CaCO₃/TiO₂ composite particles.The results shown that the surface of the CaCO₃/TiO₂ was rough,there were a large number of TiO₂ particles with a dense particle size of about 5～8nm.When the concentration of the calcium carbonate slurry was 10g/L,the tetrabutyl titanate sol was partially formed: the hydrolysis reaction [n(H₂O):n(Ti(OC₄H₉)₄)=2:1].The mass ratio of calcium carbonate to titanium dioxide was 1g:0.75g,and the reaction for 2h,the wanted composite particles were obtained.The dissolved Ca²⁺ concentration of the composite particles in the potassium hydrogen phthalate-sodium hydroxide buffer solution was the smallest,and the acid resistance was the best.