What’s the difference between absorption and adsorption and sorption?

The terms absorption and adsorption are used freely to indicate the same process of taking moisture from the air using desiccants, mostly because we don’t want to complicate the explanation of what our product does. But there is a difference.

Absorption generally refers to two phenomena which are largely unrelated. In one case, it refers to when atoms, molecules, or ions enter some bulk phase – gas, liquid or solid material. For instance, a sponge absorbs water when it is dry.

Absorption also refers to the the process by which the energy of a photon is taken up by another entity, for example, by an atom whose valence electrons make transition between two electronic energy levels. The photon is destroyed in the process. The absorbed energy may be re-emitted as radiant energy or transformed into heat energy. The absorption of light during wave propagation is often called attenuation. The tools of spectroscopy in chemistry are based on the absorption of photons by atoms and molecules.

Adsorption is similar, but refers to a surface rather than a volume: adsorption is a process that occurs when a gas or liquid solute accumulates on the surface of a solid or, more rarely, a liquid (adsorbent), forming a molecular or atomic film (the adsorbate). It is different from absorption, in which a substance diffuses into a liquid or solid to form a solution.  This is what happens to calcium chloride desiccants in container shipments.

Sorption encompasses both processes, while desorption is the reverse process.

* Taken from Wikipedia.

Wikipedia: Absorption (chemistry)

Wikipedia: Absorption (light)

Wikipedia: Adsorption

Wikipedia: Sorption


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Desiccant use at home, warehouse or boat.

Advice on solving humidity problems

Excess humidity at home can cause the appearance of mould, mildew, fungus and all kinds of nastiness that endangers your and your family’s health.

In order to solve the humidity problems in a room, bathroom, store room, etc. first of all you need to find out the cause of the excess humidity:

If the humidity comes from outside, caused by a leak or by defective insulation, our products will help to reduce the level of ambient humidity, but will not solve the problem for good. The best thing to do is to consult an insulation specialist so as to solve the root of the problem.

If the problem is due to excess ambient humidity in the room because of poor ventilation or condensation, our product can solve your problems.

How does it work?

Put the product anywhere in the room and leave it to work. The desiccant will activate automatically, absorbing the excess humidity. Once the desiccant has stopped absorbing, put in a refill. How long the product lasts depends on the temperature and level of humidity in the room.

It works without electricity or batteries.

Nordic Power Desiccant regulates the level of ambient humidity to bring it down to the recommended optimum level of 45-50%, without drying out the atmosphere, absorbing only the excess humidity.

Is it toxic? Can I use it in a child’s bedroom?

All Nordic products are non-toxic. They can be used without any problem in any room in the house, whether inside a wardrobe, in bathrooms or in store rooms – even in bedrooms. They are also very popular for use on a boat or yacht.

The desiccant contained in the product is calcium chloride, hygroscopic salts which are non-toxic and environmentally friendly.

Finding and Identifying Basement Mold

From: http://www.doityourself.com/stry/finding-and-identifying-basement-mold

Basement mould is a term refers to the types of fungus that grow in basements under certain conditions. Basement mould is harmless in small quantities, but as it grow, it becomes more and more of a health hazard. Some will cause certain types of allergic reactions while others are outright poisonous. If left untreated, the basement mould will keep growing, eventually spreading through the entire building. This is why you must find the mold before the problem gets out of hand. Once you find it, you will need to be able to identify it—otherwise, you won’t be able to figure out how to get rid of it.

Finding Basement Mould

One of the easiest ways to identify the mould is by it’s stench. However, this is only true for some types of basement mould, others may not start to smell until their growth reaches a certain stage. That is why you may want to take a more proactive approach and check the spots where the mould is most likely to emerge. That way, you will have a better chance of spotting it while it is still at manageable size.

Basement mould needs a wet environment in order to grow. It will grow near the pipes and along the walls. The mould feeds on common household materials such as plywood, drywall, furring strips and carpet padding, as well as dust and cellulose in carpets themselves. Try to check any parts of the basement that are hospitable to mould at least once every week. Be sure to bring a flashlight with you—you may not be able to get adequate illumination without it.

If your basement suffers any sort of flooding, the walls will become infested with mould spores, which will remain dormant until they come in contact with water. The spores can remain dormant for a long time. Just because the mould didn’t develop after the flood doesn’t mean it won’t become an issue several years down the line.

Mould Safety

If you find a patch of mould, try not to inhale too deeply and don’t touch the mould with any part of your body. If it gets on your clothing or your tools, wash it immediately. You can identify the mould by sight, so there is no reason why you should be touching the mould in the first place.

Identifying Basement Moulds

Basement mould can be identified based on a number of factors. First, there is colour. Basement mould comes in a variety of colours that range from light gray to black. They may have  green, blue and/or brown tinges. If the mould is closer to black, it is either the Stachybotrys or Cladosporium molds. If it’s closer to light grey, it is either Aspergillus or Fusarium moulds.

To figure out which type of dark mould and you have, look at the texture. If the basement mould looks slimy, it is probably Strachybotrys. Otherwise, it’s Cladosporium.

To figure out what kind of light coloured mould you have, look at the growth pattern. If the mold grows in disjoint circular patches, it is most likely to be Aspergillus. Otherwise, it’s Fusarium.

The Next Step

If possible, try to get the mould tested in a lab. While the factors described above are usually fairly good indicators, only the professional analysis will be able to tell for sure. If the mold patches are small, you may be able to remove it yourself. However, if the patches are fairly large, you will need professional help.

From: http://www.doityourself.com/stry/finding-and-identifying-basement-mold