Silica gel

Silica Gel is a porous, granular form of silicon dioxide made from sodium silicate. Despite its name it is asolid and hard gel . Its great porosity of around 800 m² / g, makes it a water absorber, for this reason it is used to reduce humidity in closed spaces; normally up to forty percent.

Listed as the one with the highest absorption capacity of those currently known. It is a chemical substance with a crystalline appearance, porous, inert, non-toxic and odorless, insoluble in water or in any other solvent. It is a product that can be regenerated once saturated, if it is subjected to a temperature of between 120-180 Cº. Heating it will release the moisture it has absorbed so it can be reused over and over again without affecting the absorption capacity, it will only be affected by the contaminants that the absorbed fluid has.


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  • 1 Features
  • 2 Main applications
  • 3 Uses of Silica Gel sachets at home.
  • 4 Sources


This gel is non-toxic, non-flammable, and chemically reactive. However, the gel pellet bags carry a warning about their toxicity if swallowed. It is because Cobalt Chloride, which is usually added to indicate the humidity of the gel, is toxic. The Cobalt Chloride reacts with moisture when dry is blue and turns pink to the moisture absorption.

It is a chemical substance with a crystalline appearance, porous, inert, non-toxic and odorless, with a molecular chemical formula SiO2 nH2 O, insoluble in water or in any other solvent, chemically stable, it only reacts with hydrofluoric acid and alkali . Thanks to its unique chemical composition and physical structure, Silica Gel has characteristics unmatched by other similar materials, such as high absorption, stable thermal performance, stable physical characteristics, relatively high mechanical strength, etc., depending on the pore diameter Gel is categorizedSilica as fine pore or macro porous, each with a different absorption capacity depending on the relative humidity, so the choice of type must be adjusted according to the conditions of use. The Gel Silica can also differentiate adsorption of different molecules acting as a selective absorber.

Main applications

Static dryness

  • Moisture proof packaging (electronic and photosensitive materials).
  • Applications of precision and electrical instruments.
  • Medicines
  • Shoes and clothes.
  • Leather products.
  • Dehumidification of cabinets or closed spaces.
  • Musical instruments.

Dynamic dryness

  • Dry air in warehouses, pharmaceutical laboratories, precision and electronic instrument factories.
  • Compressed air.
  • Dehydration
  • Manufacture of industrial gases.
  • Control of humidity in the environment.

Absorption and separation of substances

  • Separation of impurities in the petrochemical industry.
  • Synthetic chemical industry.
  • Electric power stations.
  • Refinement of organic chemicals.

Chemical analysis and testing

  • Analysis and separation of natural and synthetic organic materials.
  • Quantitative and qualitative analysis of components or impurities contained in medicines.
  • Herbal medicine materials.
  • Organic groceries and chemicals.
  • Separation or refining of some substances.


  • Catalyst carrier or catalyst in petrochemical, organic and synthetic chemical industry.

Liquid dehydration

  • Dehydration of organic solvents.
  • Dehydration of methanol , ethanol , benzene , toluene , gasoline .
  • Dehydration of refrigerants ( ammonia , freon , dichloromethane).
  • Oil dehydration.

Uses of Silica Gel sachets at home.

  1. Dry Paper Files:Place a couple of Silica Gel sachets in folders, envelopes, or drawers where you keep important documents to prevent them from being damaged by moisture or turning yellow over time.
  2. Forever Flawless Printed Photographs:Keep photographs moisture-free, both in albums and on paintings, by placing a silica envelope next to them.
  3. Extends the life of photography equipment:Stores cameras and photography supplies along with silica gel envelopes to prevent moisture from affecting equipment.
  4. Prevents rust on tools:Put silica gel in the tool box to prevent rust. This tip is very useful if you are one of the people who uses the toolbox a little.
  5. Keeps the seeds dry:Place an envelope of silica gel next to your seed envelopes so that the moisture does not spoil them.
  6. Dry wet electronics:If your phone or mobile device got wet, you should first towel dry it, remove the battery, and insert it open into the silica gel.
  7. Always shiny silverware and silverware:Place a silica gel envelope inside the silverware case and inside your jewelry box so that your silverware does not become opaque.
  8. Odorless Suitcases:Place Silica Gel sachets in closed boxes where you store any type of item, even in suitcases.
  9. Leather coats without mold or moisture:Put silica gel envelopes in the pockets of the leather coats, cloth and everything else that you do not use so much.
  10. For videotapes or audio tapes:Store a few sachets of silica gel next to collectible videotapes or audio tapes. When you want to see or hear them, they will be in good condition.


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