Technology of Tosoh Silica Corporation

Overview of the manufacturing process

First, a reaction is induced between liquid sodium silica (liquid glass) and nitric acid, generating SiO2 and nH2O, in a reaction tank. The reaction conditions are selected to produce silica with different features such as different particle sizes, surface structures, and pore distribution. Next, the wet silica cake is dried, ground, and classified to create the product.

A calcium chloride solution is also added to the filtrate that the silica was separated from to produce good-quality chemical gypsum with a high degree of whiteness. This high purity gypsum is used in molds for ceramic tiles, molds for teeth, and in fine and applied arts.

Process of producing synthetic silica

Hydrated amorphous silicon dioxide (synthetic silica) is produced when silicate soda reacts with nitric acid. The size, bonding, and structural characteristics of the primary particles are strictly controlled for each product grade.

Raw material (silicate soda)

Reaction formulas

Raw material reaction formulas | Tosoh Silica Corporation

Quartz sand is used as the silica source.

Silica manufacturing method

(1) Wet Method

Silica manufacturing method | Tosoh Silica Corporation

(2) Fume Method

Silica manufacturing method | Tosoh Silica Corporation