Cerium oxide

[Wayne Harridge]

On 8/6/2022 at 11:11 PM, colinbm said:

Wayne, the ZWB filters have phosphor in the mixture of the glass that reacts with the humidity in air.
 

Ok, so store them in a sealed box with silica gel?  I had one that had a film on it when it arrived from China which I'm now tempted to clean up.

 

[colinbm]

Yes They can arrive like that too, even though they insist it was pristine when it left, yeah right !
 Storing with silica gel is attracting moisture into the box, that you don't want any moisture in, in the first place.
You could purge the air-tight box with an inert & dry gas like argon.
Or you can use a automotive windscreen rain repellent to protect the glass from moisture & extend the time between the need to be cleaned, works for me in sunny humid QLD.
 

[Fandyus]

Thank you for the tips.

[Andy Perrin]

11 hours ago, colinbm said:

Storing with silica gel is attracting moisture into the box, that you don't want any moisture in, in the first place.

This is incorrect advice. If the box is really air-tight, it won't attract moisture into the box because moisture can't get in from the outside. 

[colinbm]

The ZWB filters have a greater affinity for absorbing water vapor then the silica gel, so any moisture in the gel will be attracted to the filter.

 

[Andy Perrin]

That's not how it works - even if it were true that the ZWB absorbs better than a silica gel packet that is actually MADE TO ABSORB WATER, you could just add more gel packets to compensate. 

[colinbm]

My S8612 still got the pox with silica gel.

[Andy Perrin]

Then you either didn't have enough gel in there to absorb all the water, OR the container wasn't truly airtight (or both).

 

This is assuming the pox only happens under humid conditions — it may still happen even in low humidity (I am not sure about this). I do know humidity accelerates it.

[colinbm]

What testing have you done Andy ?

[Andy Perrin]

Colin, this is common knowledge. We don't have to do fancy experiments. It is why you find the packets in every bag of trail mix, and why you find them in many electronics packages.

 

The burden of proof is on the one claiming extraordinary things, like that silica packets don't work. I think you are drawing the wrong conclusions from your experiences.

[colinbm]

Common Knowledge is not very common.
You are shooting from the hip without showing proof.
I have demonstrated plenty of proof & done the hard yards.
Have you ever had this problem with ZWB or S8612 ?

[Andy Perrin]

Sure, my S8612 shows some oxidation now and then. My own humidity is already pretty low, so it's not been such a big problem for me, I just wipe it off or use the peroxide. But honestly, you are just being ridiculous, and I think I'm done. I wish you would stop repeating this false information, though. 

[colinbm]

Contrary, I wish you would stop repeating this false assumption until you have experienced the real big problem like too many are facing & get on top pf the solutions.
Just because it doesn't affect you, doesn't mean it doesn't exist !

[Doug A]

@Andy Perrinand @colinbmthere are other choices besides silica gel. https://absortech.com/moisture-magazine/silica-gel-desiccants-moisture-absorption-things-you-need-to-know/. 

 

Glad I found a coated S8612.

Thanks,

Doug A

[ulf]

SilicaGel is well documented as a water absorbent agent.

https://www.sorbentsystems.com/desiccants_charts.html

https://www.google.com/search?q=Adsorption+silicagel&tbm=isch&ved=2ahUKEwiLkJjDzr75AhVJAxAIHXedAp4Q2-cCegQIABAA&oq=Adsorption+silicagel&gs_lcp=CgNpbWcQAzoECCMQJzoFCAAQgAQ6BggAEB4QBToGCAAQHhAIOgQIABAYUOodWL48YIFAaABwAHgAgAE9iAGLBJIBAjEwmAEAoAEBqgELZ3dzLXdpei1pbWfAAQE&sclient=img&ei=hd70Ysu5FMmGwPAP97qK8Ak&bih=1127&biw=1913#imgrc=AM8IOrzP_0JKeM

 

However most glass materials are also known to have surface adsorption properties leading to glass corrosion and there might be some interaction with some filter materials.

However SilicaGel will not make it worse as it will lower the humidity in a closed container.

 

The problems that Colin has seen with SilicaGel might be due to unfortunate combinations of environmental factors or unsuitable  storage containers.

He is living in a hot humid place and that is the worst for filter storage.

[colinbm]

Thanks Doug
Something new to me this Calcium Chloride, I need to get some & try it.
More to the point I was trying to get across.....

• Silica gel works well at unexceptional temperatures, while it may lose the capacity to adsorb at higher temperatures. At high temperatures, it might actually release moisture into the air.

Also one of their tests...
Placed in an environment with 30 degrees Celsius and 90% relative humidity.
That is a mild day for me !