The invention discloses a preparation method of core-shell structure high-white
precipitated calcium carbonate. The method comprises the steps that digesting, screening,
impurity removing and aging are conducted on low-quality-level and low-white quick
lime, a crystalline form controlling agent is added to conduct
carbonation reaction, and a formed low-white
calcium carbonate particle is taken asa core; digesting, screening,
impurity removing and
ageing are conducted on high-white quick
lime, the high-white quick
lime is grafted to a core surface after
carbonation reaction to be taken as a housing, filter pressing dehydrating,
drying, pulverizing and grading are conducted after the reaction is completed, and the core-shell structure high-white
precipitated calcium carbonate is obtained. According to the method, the white level of a
calcium carbonate product with the white level of below 90 degrees can be improved to 90 degrees or above by the
calcium carbonate prepared by the method,particular
diameter distribution of the product is concentrated, the dispersing performance is good, the
calcium carbonate is applied to PVC panels and tubular materials, and
processing performance, whitening and
toughening are achieved. The product technology is simple and implementable, the cost is low, the price is cheap, and the
economic benefits are better.