FREQUENTLY ASKED QUESTIONS
What is a desiccant and what does it do?
A desiccant is a hydrating agent which attracts moisture from the atmosphere. It adsorbs and holds Particles of water to itself.
Silica gel is a desiccant then?
Yes, it adsorbs moisture by physical means, not by a chemical reaction. Water vapor is attracted inside the silica gels crystalline structure.
What is Silica Gel?
Silica gel is a form of silicon dioxide (SiO₂), the same material found in sand. While sand is crystalline and non-porous, silica gel is non-crystalline and highly porous, making it effective at adsorbing moisture. It is synthetically produced through a chemical reaction between sodium silicate and sulfuric acid. Odorless, tasteless, and non-toxic, silica gel has excellent moisture control properties due to its stable chemical nature, high surface area, and strong mechanical strength. It is widely used for protecting pharmaceuticals, food, electronics, and export goods. Moisture-saturated silica gel can be easily regenerated by heating.
What is the right way to use desiccants?
Desiccants are most effective when used inside a sealed or enclosed environment. This prevents outside moisture from continuously entering and allows the desiccant to efficiently control the humidity.
Who are our clients?
We provide customized absorbent solutions to a wide range of industries, including pharmaceuticals, leather, food packaging, dry fruits, paper, technology, automotive, petrochemicals, cosmetics, power plants, shipping companies, and many more.
So, silica gel, not really a gel then ?
No, Silica gel is not a gel. It's a solid substance that can be granular or beaded. The size of the granules or beads determines how they are sorted. The grain size of silica gel in sachets is normally unimportant, but for uses like drying flowers, a fine grain silica gel is preferable to a broad grain silica gel. A grain size of 0.5-1.0 mm rather than 1.0- 3.0 mm or 3.0 - 6.0 mm. The larger grain sizes are ideal for complex drying applications, such as passing air through a bed of silica gel to dry it.
But does silica gel get wet as it adsorbs water?
No it doesn't, one tremendous feature of silica gel is that it traps water molecules inside its pores yet remains totally dry and appears physically unchanged. It does not swell or change shape.
Does silica gel come in different colors?
Yes, silica gel is available in two types: non-indicating and self-indicating. Non-indicating silica gel is clear or white and does not change colour when it absorbs moisture. Whereas, Self-indicating silica gel changes colour to show how much moisture it has absorbed. For example, Blue silica gel will turn pink when saturated with moisture.
Does silica gel comes ready to use?
Yes. The silica gel does not need to be 'generated' before use. It is always sold (loose or in sachets) in a dry condition, ready for use.
How long can silica gel be stored?
Almost indefinitely. The key to retaining a sachets usefulness is to keep it under air tight conditions until it needs to be used. Silica gel will adsorb moisture from any environment, so a sachet left out in the open will immediately start taking up water vapor. Although the moisture uptake rate is not fast, small sachets can be vulnerable to such exposure, as they do not have large moisture holding capacity. It is recommended that they are not left open to the atmosphere for longer than 15 minutes. Larger sachets should not be removed from their packaging more than 1 hour before they are required for use. The shelf life of silica gel in a sealed environment can safely be said to be between 4 and 12 months. Practical experience has shown that it can often far exceed this.
How much water vapor can silica gel hold?
Silica gel will adsorb up to 30% of its own weight in moisture.
Can silica gel be used anywhere?
Silica gel is most effective in enclosed or sealed environments. While it can be used anywhere, it performs best where airflow is limited, as continuous exposure to new air and moisture reduces its effectiveness.
What is Relative Humidity?
Air always contains some amount of water vapor. At any given temperature, there is a saturation point — the maximum amount of moisture the air can hold before excess begins to condense. Relative Humidity (RH) is the actual amount of moisture in the air expressed as a percentage of that maximum (saturation) level.
The purpose of using silica gel is to maintain relative humidity below 50%, a level at which corrosion, Mold growth, and other moisture-related damage are minimized.
Is silica gel dangerous?
silica gel is non-toxic and non-flammable, it is very inert with a very high melting point. It is very much like sand and thus can safely be sent by any means of transport.
How can silica gel work when it's inside a sachet?
The materials used to make silica gel sachets are specifically chosen to be breathable. Water vapor passes through them to be adsorbed by the silica gel.
Why are there so many different size sachets?
The larger the item that is being protected, the more silica gel is needed. For different area and purpose we have a range of sizes to target the moisture problem.
What are the most popular moisture-related issues?
Mold, fungus, mildew, rust rotting, lumping, caking, agglomeration, and decomposition are all issues caused by moisture in containers. Electronics can also be damaged by moisture.
And which size sachet should I use?
It will depend on the application. For a well sealed item, a rule of thumb is that 5 grams of silica gel are needed for every cubic foot of volume of the package. This converts to 170 grams per cubic meter.
How is silica gel regenerated?
Self-indicating silica gels when they have become saturated can be regenerated by heating at 100-120°C until they return to their original colours. The heating literally drives off the adsorbed moisture. Regeneration can be carried out repeatedly, although eventually the crystals will lose their co lour. When regenerating self-indicating silica gel sachets, only the minimum necessary heat should be used. This will prevent the sachet material from deteriorating. Although non-indicating silica gel can be regenerated in exactly the same way, it is not apparent when the silica gel is regenerated other than by checking its weight. it will return to its original dry weight when completely regenerated.
Non Standard Sizes And Special Sachets
The above sachets represent our standard range of off the shelf items. In addition to this we are able to manufacture sachets to any other weight that meets customer requirements. We will also manufacture totally non-standard silica gel sachets, sachets of specific (and unusual) shape, sachets with loops or lengths of tape attached, sachets with Velcro, sachets in bandoliers or sachets that are individually over wrapped in foil or poly pouches. Finally, sachets can be made using a mixture of materials e.g. silica gel and activated carbon.
Pricing And Packing
We try and sell sachets in almost any quantity that we are asked for. They are supplied in strong cartons with heavy gauge poly bags. If required, packaging can be tailored to suit individual needs In generate non-indicating silica gel sachets are cheaper than self-indicating sachets and to double the weight of silica gel does not double the cost. Prices are tiered, with price breaks as quantities increase. Often dramatic decreases in cost will accompany increased quantities.
Please contact us for prices data sheets,samples or advice.
