Colloidal silica is a highly dispersed colloidal solution of nano-sized silicon dioxide (SiO₂) particles in water . Its chemical properties are primarily determined by its high specific surface area, abundant surface silanol groups (Si-OH), and stable Si-O-Si chemical bonds .

The surface of silica sol particles is covered with a large number of active silanol groups (-SiOH), giving it extremely high chemical reactivity .By virtue of its enormous specific surface area, silica sol can effectively adsorb organic matter, metal ions, and suspended particles from solutions, forming the basis for its use as an efficient clarifying agent and adsorbent .

It can be used in industrial bonding and casting,precision machining and polishing,coatings and surface treatment,textiles and papermaking,environmental protection and energy,catalysts and etc.