| 摘要 |
<p>Disclosed is a method for preparing precipitated silica, by reacting using a soluble silicate M2O.nSiO2 and a bicarbonate MHCO3 as raw materials, the mole ratio of M2O.nSiO2 to MHCO3 being 1:2.0-2.3, precipitating SiO2 hydrate, separating the filtrate after filtering, and washing and drying the filter cake to obtain a precipitated silica product. The filtrate mainly comprises carbonate M2CO3 and a small amount of bicarbonate MHCO3, wherein M is an alkali metal element Na or K, and n is the modulus thereof. Since the filtrate mainly comprises carbonate M2CO3 and a small amount of bicarbonate MHCO3, the raw materials for the reaction can be obtained by various treatment methods, and can be recycled, thereby decreasing the manufacturing costs, at the same time reducing consumption of resources, lessening emissions, decreasing damage to the environment, and avoiding the problems in the prior art such as the consumption of a large amount of inorganic acid and environmental pollution.</p> |
