How to Recharge Silica Gel

How To Recharge Silica Gel Crystals

Silica Gel absorbs moisture in the air around your camera equipment (such a material is called an adsorbent). This ensures that the area is not friendly for fungus to grow inside your camera lenses (article I wrote about keeping fungus at bay). But did you know that if you leave silica gel inside your camera bag for too long it can get saturated with moisture and actually start to give off some of that moisture later on? This could really mess up your equipment. I didn’t know this myself, until a few years ago.

Here’s how you can avoid this potentially huge problem, and recharge / reuse Silica Gel sachets or crystals that you use to keep your camera equipment safe from moisture.

What Type of Silica Gel Should I Buy?

Different types of Silica Gel
Different types of Silica Gel

Silica Gel comes in a few different forms. Typically they’re sold loose, as crystals, tiny spheres, or in porous plastic sachets that allow air through. I prefer to get the loose spheres or crystals because it’s not easy to see when the crystals are saturated when in sachets. More specifically, I prefer to buy indicative Silica Gel. This is also called reactive Silica Gel.

The sachets are very convenient for some non-photographic uses.

How Do I know When My Silica Gel is Saturated with Moisture?

Normal Silica Gel is white, so it’s difficult to know when it is saturated with moisture. This is why I prefer to use Indicative Silica Gel. These Silica Gel crystals are blue when fully active, and become pink when they are saturated with moisture. There is also a variety that is orange when fully active, and that turn green when saturated. The orange type is preferred, as the chemical used to show moisture content may be less toxic.

Quick TIP: You can keep track of how humid any space is, by using a Digital Hygrometer. I highly recommend using one.

How Can I Restore or Recharge Silica Gel that is Saturated?

Silica Gel gets saturated with moisture rather quickly when there is a high level of humidity in the air. So, it’s important to check on the crystals / sachets often. Fully Saturated Silica Gel crystals can begin to give off humidity to the surrounding air when the humidity falls. This means that you need to refresh / recharge the crystals before they get saturated, so that they continue to absorb water from the air.

The good news is that you can reuse these Silica Gel Crystals as many times as you like, and the procedure is quite simple. All you need is an oven, an oven-safe dish, maybe some aluminium foil to hold the crystals, and you’re ready to recharge Silica Gel.

8 Steps to Make Your Silica Gel Reusable:

  1. Spread the crystals across the bottom of a bake-safe oven dish (you can use aluminium foil if you prefer to keep it off the dish itself). Spread them evenly and less than an inch deep in the dish.
  2. Place the dish in an oven and heat it to 120° C (250° F) for 1–2 hours until they start changing colour. If you want to avoid the risk of making your Silica Gel inactive, you could use a lower temperature and leave the Silica Gel in for a longer period of time.
  3. CAUTION: Do not heat Silica Gel to more than 180° C because it will lose its ability to absorb moisture.
  4. The Silica Gel crystals will release the trapped water from within them, and will revert to their original blue or orange colour. Once the colour changes fully, the Silica Gel is recharged and restored to its original capacity.
  5. Note that the chemical that actually indicates the there is water in the silica gel crystals is a little more sensitive, and will most likely turn blue before the Silica Gel is fully refreshed. This is why we suggest leaving the crystals in the oven for a while longer, after the crystals turn blue / orange.
  6. Allow the crystals to cool down before you touch them, and then restore them to their perforated containers in your camera bag or cabinet.
  7. Store them in an airtight container so that they don’t absorb moisture from the atmosphere when they are not in use. Also, use an airtight storage container for your camera equipment so that humidity doesn’t come in from outside and saturate the Silica Gel crystals.
  8. Remember to recharge your Silica Gel crystals often enough, and your camera equipment should last a very long time.

Some people say that you can use a microwave oven to recharge Silica Gel, however we recommend against it because there is no way to control the temperature of the crystals, and you risk making them inactive.

Is Silica Gel Toxic?

No, Silica Gel is not toxic, but you should not try to ingest it, or mix it with edible items. Also keep it away from children, eyes, etc.

In short, treat it with enough respect and you will be safe. Follow the link above for more information about precautions around children.

The Cobalt Chloride used in blue>pink indicative Silica Gel has been classified as hazardous if inhaled or ingested, so if you’re using indicative Silica Gel, don’t inhale the dust from the crystals. The Orange > Green Silica Gel is considered safe for use.

Where Can I get Indicating Silica Gel?

Personally, I use orange beads of Silica Gel.

Now That I’ve Recharged my Silica Gel Sachets, How Can I Reuse them?

Glad you asked! Silica Gel is useful around the house and office in more ways than to just keep your Camera Equipment safe. Here’s a short list.

  • Of course, keep some in your camera storage area, as well as your travel camera bags. They’re essential.
  • Keep your paperwork or clothes free of mold in humid regions.
  • Quickly dry out electronic equipment if they get splashed. Of course, remember to it off before doing anything else. You can put your phone, or other device into an airtight container full of indicative Silica Gel crystals, or Sachets to get it dry super fast.
  • Put some Silica Gel in with photo albums, when storing them, to prevent photos sticking to the cellophane pouches.
  • Put Silica Gel sachets in your luggage, and especially in your Travel Pouch to keep the insides dry, and prevent your razors from rusting while you travel. This is especially useful when travelling to beaches and tropical climates.
  • Keep some Silica Gel in your toolkit. This will keep the air dry and prevent rust.
  • Every storage container needs a little Silica Gel.
  • You can create art quicker by storing flowers and leaves with Silica Gel. This will dehydrate the flowers quickly, making for artistic subjects for your photography or art projects.

More Information

Thanks for reading right through to the end. Follow this link if you want more information about how to take care of your cameras when it’s raining, or if you live in a humid area.

10 thoughts on “How To Recharge Silica Gel Crystals”

  1. Hi Susheel, recently acquired a new dry cabinet wth digital indicator outside ,but has a manual setting inside the cabinet ,which is set for RH of say 43 %.Is such type of dry cabi.is any way less efficient than the one called ‘digital’,which has controls outside the cabinet?I wl have to ,anyway,open the cabi.to get my gear out ,right?So whats a big deal of having control outside?
    Pls xplain d diff.I am confused..I already invested in a ‘manual’ Dehumidifier.Regards.Dr.Mhatre

    Reply
    • Hello Dr. Mhatre,

      Thanks for stopping by and leaving your comment. From what I understand, the efficiency of the dehumidifying mechanism would not vary much based on digital or manual controls and / or their placement. Usually, digital controls do offer more fine-grained control over the RH that is maintained, turning the mechanism off and on more frequently than analog controls. PS: these cabinets do not need to have their settings changed once set. They’re essentially set-and-forget. 40% seems like a good place to keep the RH. I don’t think you should ever need to change it. So based on that, you could decide to get the one with the controls inside the cabinet, or outside. Do let us know what you decide to do. Your insight could prove valuable to others. Thanks 😀

      Reply
  2. good day for all,
    i would like to ask about the optimum way to use silica gel blue(2-4 mm) as a dryer, what is the required quantity to the suitable area, humidity, ….
    thanks

    Reply
    • Hi Ahmed,

      While there are some research papers that talk about how much silica gel to use per x volume of air for long term storage, these papers are directed towards use for museum showcases, and for the preservation of manuscripts and other fragile items. I’d suggest that you should decide the relative humidity level that you want to maintain, then get a hygrometer to check the actual humidity of the space. Experiment so that you’re able to maintain a humidity level that you’re comfortable at. I personally put about 100 grams of the orange balls into a perforated plastic container to get the humidity out of a 2x4ft box. I change the silica gel beads every week or two. I think that it has worked for me so far.

      Hope that helps.

      Susheel

      Reply
  3. i agree with this article. Working with Sorbead India in this industry have opened my eyes as to how vital are those silica gel packets.

    Reply
  4. I was just curious if anyone has ever tried using an air fryer to recharge desiccant?
    Or if you think that may be a suitable methods?

    Reply
    • Hi Adam, Not having used an air fryer I couldn’t really tell you for sure. A quick search shows me that Air Fryers typically operate at 200 Degrees Centigrade. This is too hot for Silica Gel, which needs about 100 Degrees Centigrade. If yours has a variable temperature that goes down to 100 Deg Celcius, you can definitely give it a try. Let us know what happens. 🙂 Thank you for stopping by and commenting.

      Reply

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