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Hydrogen Peroxide experiment on old, discolored bricks

Posted: Wed Jun 29, 2005 4:46 am
by SavaTheAggie
Entire Post Mod Gallery

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Day #1

An assortment of discolored "classic" light grey and white bricks, saving some of similar discoloration out as a control. The picture on the upper left is with a flash, the other without. Here you can see some of the white bricks are badly discolored. The light grey bricks have roughly the same amount of discoloration and are about the same color.

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(Day #25)

The containment unit. Hydrogen Peroxide is basically made up of water molecules with an extra oxygen atom. Because of this, it is relatively unstable, reacting to both air and water, and gives its free oxygen atom up easily. To counteract this, I stored the bricks and peroxide in an air tight container in an unused cabinet.

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Day #25

*obligatory 'whoosh' noise as the containment vessel opens*

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Day #25 - White Bricks

Here you can see the white bricks that were soaked lying on a new white baseplate, along with one of the control white bricks. The white bricks were not totally whitened 100%, but they were considerablly better in color than the control.

I theorize a few more weeks and they would whiten further.

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Day #25 - Light Grey Bricks

I'm not sure what to make of this. On top you can see the control Light Grey brick, and on the bottom you can see a new Light Grey brick.

Inbetween it looks almost as if there are two Very Light Grey colored bricks and one "New" or "Bley" Light Grey Brick. Had they all turned lighter, I would have surmised that their color had been bleached out. As it is, I have no idea what to think.

--Anthony

Posted: Wed Jun 29, 2005 6:38 am
by LEGOFREAK
wow. and to think I almost tossed that box of yellowed white bricks. :D I think they can be saved now.
the greys though, I dont know what to do with them..

Posted: Wed Jun 29, 2005 8:39 am
by Sir Nelson
Thanks for sharing this technique and your findings. It's pretty neat how those white pieces became closer to their original color. We should call this the "HBP" (Hash Brown Potatoes) method of cleaning bricks... Do NOT open!!! :P

Did the resulting 'white' HPB bricks have any odor, or distinctive feel to them? You mentioned that it needed to be in a dark environment... I wonder if the container was exposed to light/heat, what would the impact be?

I guess if you happen to acquire a large lot of classic grey bricks and use this method, you could use the resulting bricks to produce a truly mottled castle.

Re: Hydrogen Peroxide experiment on old, discolored bricks

Posted: Wed Jun 29, 2005 8:28 pm
by Tedward
Where's the object, method conclusion etc? Sheesh! Didn't you learn how to write up experiments in Grade 5? :wink:

But seriously, what concentration of hydrogen peroxide did you use? I believe it comes in different percentages does it not?

Gotta go soak some old white bricks... :D

Posted: Thu Jun 30, 2005 10:39 pm
by venvorskar
Interesting method. Where did you get the idea?

Posted: Wed Oct 26, 2005 4:35 pm
by SavaTheAggie
Brining up another old topic...

Once again, I left questions unanswered... I'm a terrible admin, I am.

Question 1:
Sir Nelson wrote:Did the resulting 'white' HPB bricks have any odor, or distinctive feel to them? You mentioned that it needed to be in a dark environment... I wonder if the container was exposed to light/heat, what would the impact be?
Hydrogen Peroxide is inherently odorless, and so were the bricks. The hydrogen peroxide was also not concentrated enough to do any sort noticable physical damage to the bricks to change their surface texture or ability to be built with.

Hydrogen Peroxide is not only reactive to air and water, it is so unstable it reacts to light. Exposing the container to light and/or heat would simply reduce the Hydrogen Peroxide into its two, more stable sub-components: water and oxygen. In short, nothing would happen to the bricks (aside from getting wet).

Question 2:
Tedward wrote:Where's the object, method conclusion etc? Sheesh! Didn't you learn how to write up experiments in Grade 5? :wink:

But seriously, what concentration of hydrogen peroxide did you use? I believe it comes in different percentages does it not?
I did go to regionals once, in the science fair...

I used the normal, over the counter 3% solution of Hydrogen Peroxide, the same concentration any Joe off the street can purchase. A user on Bricklink just recently posted about using a stronger concentration of 35% (which is what reminded me of this thread) doing the same job to white bricks in 4 days instead of a month. Getting 35% H2O2, however, is a bit tricky.

Question 3:
venvorskar wrote:Interesting method. Where did you get the idea?
The same bricklink user from Question 2 first started a thread about using 3% H2O2, comparing it to using a bleach solution. The findings from that was that the bleach worked faster, but the H2O2 did not damage the bricks if left unchecked for too long. Using a half water half bleach solution, after a week or so, the bricks are at risk of being chemically damaged (and so I like the H2O2 method).

--Anthony

Posted: Fri Feb 10, 2006 8:27 pm
by CAI
Building, I try now to weed out the horribly discolored pieces, like the following. I will give the experiment a try, but these I believe are beyond help. Hope i will!

http://www.brickshelf.com/gallery/Cyin/Odd/fade01.jpg