Silcolapse® 454

Silcolapse® 454 offers the following advantages :

• Ease of use: Silcolapse® 454 can be used supplied, or prediluted in a solvent or in some of the medium to be defoamed. It disperses readily in most media. The product can be used with automatic injection systems.
• Efficiency: Silcolapse® 454 is efficacious at low doses, from about 1 to 100 mg per kg of medium to be defoamed.
• Inertness: Silcolapse® 454 is chemically inert towards media to be defoamed and therefore does not affect their properties.

Silcolapse® 454 has numerous applications in such fields as:

• Oil: Alkanolamine washing of natural or refinery gases.
• Crop protection products: Product formulations (emulsifiable concentrates and aqueous dispersions)
• Detergents: Manufacture of detergents powders and liquids and of soap.
• Chemicals: Distillation, extraction, evaporation, dissolution, filtration, etc.

(1) - Milligram of product as supplied per kilogram of medium to be defoamed. This concentration can also be expressed, with no significant error, as milligrams of product as supplied per litre of medium to be defoamed (mg/l).

Silcolapse® 454 is equally efficacious in aqueous and anhydrous media. It is easily dispersed provided a suitable thinner is used. Recommended concentrations and directions for use:

• Silcolapse® 454 is normally used in concentrations of 1 to 100 mg per of medium to be defoamed. It can be used as supplied, but it is often preferable to predilute it to a concentration of between 1 and 10%. To do this, slowly add either 99 or 90 parts of the thinner used to 1 or 10 parts respectively of Silcolapse® 454.
• Prediluting Silcolapse® 454: The product can be diluted either in some of the medium to be defoamed (1), or in one of the following thinners, which are all solvents of the silicone oil in the compound, and are soluble, or simply dispersible, in the medium to be defoamed.

1. Use in anhydrous media

The following thinners are recommended: 

• Aliphatic hydrocarbons (hexane, heptane, white spirit, etc.)
• Aromatic hydrocarbons (benzene, totuene, xylene, naphtha solvent, etc.).
• Chlorinated hydrocarbons (tri-chlorethylene, perchlorethylene, carbon tetrachloride, etc.)

     2. Use in aqueous media

In this case, water-soluble or water-dispersable thinners should be used, such as:

• Certain ketones, e.g. methylethylketone or methylisobutylketone
• Certain alcohols, e.g. tertiobutanol, dodecanol-1 or ethyl-2 hexanol
• Certain ethers, e.g. ethyl ether or isopropyl ether.

Methanol, isopropanol, ethylene glycol, propylene glycol, glycerine, etc. are NOT RECOMMENDED for diluting Silcolapse® 454 as they are not solvents of the silicone oil in the compound.

In the case of an aqueous medium, a master dispersion of Silcolapse® 454 can be prepared. The homogeneity and lenght of stability of such a dispersion will depend on the degree of agitation, and also on the surfactant and rheological characteristics of the medium concerned.

Remarks: Prior dilution tests are recommended in all cases before any operations on an industrial scale. The colloidal filler in the compound may result in cloudy or clear dilutions, depending on the refractive of the thinner.

Use of pre-dilutions: Examples of final concentrations of antifoam in the medium:

• 1 mg/kg dilute either 1 part of 1% predilution in 10 000 parts of the medium to be defoamed, or 1 part of 10 % predilution in 100,000 parts.
• 100 mg/kg - dilute either 1 part of 1 % predilution in 100 parts of the medium to be defoamed, or 1 part of 10% predilution in 1000 parts.

Systematic tests has to be done to determine the optimum concentration of Silcolapse® 411, which generally depends on a number of factors - composition of the medium, temperature, pH and intensity of agitation. The recommend starting dose of 10 mg of antifoam per kg of medium to be defoamed, and then increasing or decreasing this amount according to results.

Thinner : Aromatic, aliphatic and chlorinated hydrocarbons. Water-soluble solvents and Water-dispersible solvents.

When stored in its original packaging: Silcolapse® 454 may be stored at a temperature between -5 °C/ 23 °F and 40 °C/ 104 °F for up to 18 months from its date of manufacturing.