PERFORMANCE MATERIALS|

  • North America
    COUNTRY SELECTOR|
     
    Most Selected Countries
 
colloidal silica products designed for exceptionally consistent properties

Colloidal silica properties

Klebosol’s unique properties provide benefits to a wide range of applications. Our superior and exacting manufacturing processes yield a colloidal silica product with exceptionally consistent properties. This consistency can make a difference in many applications ranging from beverages to computer chip manufacturing.
 

Colloidal silica - basic facts about Klebosol

Electrolytes
Electrolytes have the potential to destabilise Klebosol and accelerate the gelling process. When Klebosol is left unpackaged, its alkaline nature is conducive to the absorption of CO2 from the air. 

CO2 absorption will form sodium carbonate, which will destabilise the suspension. Therefore, it is highly recommended that the drums are promptly closed after use to preserve any unused product. 

Bacteria
Klebosol suspensions may be conducive to bacterial growth. This can be avoided by the addition of a biocide compatible with the application for which Klebosol will be used. 

Surfactants & solvents
Klebosol is compatible with most anionic and non-ionic surfactants, as well as organic solvents. 

Cationic surfactants, such as quaternary ammonium salts, have a destabilising effect and are therefore NOT recommended. 

We highly recommend that preliminary testing be performed before formulating Klebosol with a surfactant or solvent.

Temperature
Klebosol freezes below 0°C, at which point destabilisation and gelling of the suspension will occur. Thawing the product will not restore its colloidal properties. 

At high temperatures, a loss of water due to evaporation will increase Klebosol’s solid content and potentially result in gelling.
 

Colloidal silica particle size, silica content & stabiliser type

All formulations of Klebosol colloidal silica are stable suspensions of independent (or non-agglomerated) particles of silica (SiO2). A liquid-phase process is used to grow silica particles that are non-porous and spherical, resulting in a highly stable and homogeneous suspension. By varying the (1) particle size, (2) silica content and (3) stabiliser type in differing combinations, a full range of Klebosol formulations with unique characteristics and properties can be achieved:

Particle size 
By controlling particle growth during the manufacturing process, we are able to produce highly uniform suspensions in a variety of particle sizes. Particle size variation for a specific suspension is very narrow, and large volumes of Klebosol can be manufactured with excellent batch-to-batch consistency. 

Depending on particle size and solid content, Klebosol can appear slightly opalescent to milky.
Particle size exhibits an inversely proportional relationship with respect to specific surface area: 

 

The reactivity of Klebosol increases with the number of active sites, which is directly related to the specific surface area. Therefore reactivity is improved in formulations with a smaller particle size.

Silica content
Klebosol can be formulated with differing concentrations of silica, depending on particle size:

Available Klebosol grades
Specific surface (m2/g)30020012050
Particle size in nm9122580
SiO2 50%
SiO2 40%
SiO2 30 %
 

Stabiliser type 
Klebosol colloidal silica formulations can be produced as either:

  • Anionic when stabilised with cations such as Na+, K+, NH4+
  • Cationic when the stabiliser is an Al derivative
Stabilization of Klebosol
 
Stabilization of Klebosol

 

Colloidal silica specific gravity & pH

The particular concentration of silica used will have an affect on both specific gravity and pH of the Klebosol formulation. 

Specific gravity
As outlined in Figure 1, the specific gravity of the suspension increases as the concentration of silica is increased. The particle size used in the suspension will also affect specific gravity, though to a lesser degree. 

pH
A stable formulation of Klebosol is achieved through the addition of bases, which will generate negative charges on the silica particle surface. This will cause individual silica particles to repel each other, thus resulting in a highly stable suspension. 

By lowering the pH value, stability decreases: the particles react with each other and may form a gel. The gelling rate between pH 4 and 7 is very high. 

Below a pH of 4, Klebosol is more stable and can therefore be used in acidic form. However, the acidification of Klebosol must take place very quickly in order to pass through the critical region of pH 4 to 7. 

Alternatively, a patented formulation of Klebosol with neutral pH is readily available. 

Above a pH level of 11.5, the excess of base reacts with the particles and generates sodium silicate, which flocculates. 

The optimal pH level with respect to particle size and silica particle concentration is outlined in Figure 2:
 
Klebosol gravity chart

 

Colloidal silica properties - storage, safety & packaging

Storage
With the exception of select grades, Klebosol’s shelf life is at least one year without any change in specific properties, if kept in its original unopened packaging at a temperature above 0°C. 

At standard solid content and particle size, Klebosol’s shelf life is greater than one year. Extensive ageing tests have confirmed that each relevant parameter remains constant, provided there is neither evaporation nor freezing. 

An increase in silica content shortens the average distance between the particles, and the tendency to destabilise intensifies. Conversely, dilution will increase the mean distance and improve stability. 

Dilution of Klebosol with water is possible in all proportions. 

Safety
Please contact us for the safety data sheet. 

Packaging
Packaging of Klebosol varies depending on the location of production. They are as follows:
LamotteMartin
Polyethylene drum220 litres55 gallons
Polyethylene container1000 litres275 and 330 gallons
Bulk20000 litres5500 gallons