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  #1  
Old 11-10-2004, 06:03 PM
saluki_fan saluki_fan is offline
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Will rubbing alcohol dissolve a brass screen?

If I wanted to sterilize a brass screen for a filter to put in my faucet, would soaking it in rubbing alcohol cause more damage than good? Thanks.
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  #2  
Old 11-10-2004, 06:17 PM
racer72 racer72 is offline
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What are you trying to remove from the screen? New ones are only 20 cents at my local Ace Hardware. I think that would be easier. And if you were looking for a sly method of cleaning your pipe screen, carb cleaner then a few seconds under running water does a dandy job.
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  #3  
Old 11-10-2004, 06:20 PM
Q.E.D. Q.E.D. is offline
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Nope, should be fine. Not that it'll do any good in the long run. You're going to get more bacteria from the water supply itself than you ever would from the screen. Unless you've just fished the screen out of the toilet or something.
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  #4  
Old 11-10-2004, 06:22 PM
Xema Xema is offline
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It would cause no damage at all.
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  #5  
Old 11-10-2004, 06:23 PM
Squink Squink is offline
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Brass will not dissolve in rubbing alcohol. If the screen has a mineral buildup on it, I suggest that you first soak it for an hour or so in some vinegar. That should clean it up nicely.
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  #6  
Old 11-10-2004, 06:24 PM
danceswithcats danceswithcats is offline
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IPA won't do anything harmful to the screen, but it won't sterilize it, either. Steam autoclave is what the medical folks do.
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  #7  
Old 11-10-2004, 06:32 PM
saluki_fan saluki_fan is offline
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Quote:
Originally Posted by danceswithcats
IPA won't do anything harmful to the screen, but it won't sterilize it, either. Steam autoclave is what the medical folks do.
What is steam autoclave?
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  #8  
Old 11-10-2004, 06:44 PM
Wikkit Wikkit is offline
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A pressure vessel that is pressurized and heated with steam. Like a beefed up pressure cooker. Not something that most people have at home, though I do have one in my coat closet.
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  #9  
Old 11-10-2004, 06:45 PM
danceswithcats danceswithcats is offline
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The method by which medical practitioners sterilize instruments. Hospital workers make up packages of tools, seal them with a color/temperature tape that displays striped bars when the appropriate temperature is reached for sterilization, and you thereby have a visual indicator that a given instrument set is sterile.
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  #10  
Old 11-10-2004, 06:58 PM
Roches Roches is offline
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A filter for your faucet, right. I would recommend contacting your municipal water authority if your faucets are regularly becoming clogged with tar, as this could indicate a serious problem with your water supply.

The reactivity of various metals with acid can be summarized with an activity series: Li > K > Ba > Sr > Ca > Na > Mg > Al > Mn > Zn > Fe > Cd > Ca > Ni > Sn > Pb > H > Cu > Ag > Hg > Au. Metals towards the beginning of the list will react with relatively weak acids such as water. Metals towards the end will not react except with very strong acids. Alcohols, including rubbing alcohol, are relatively weak acids compared to mineral acids (sulfuric, hydrochloric, etc.) and even organic acids (acetic, citric, etc.). Some metals would react with rubbing alcohol, but Cu and Zn are unlikely to dissolve in rubbing alcohol. Prolonged exposure of a brass object to water or rubbing alcohol may result in corrosion, though.
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  #11  
Old 11-10-2004, 07:17 PM
saluki_fan saluki_fan is offline
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Quote:
Originally Posted by Roches
A filter for your faucet, right. I would recommend contacting your municipal water authority if your faucets are regularly becoming clogged with tar, as this could indicate a serious problem with your water supply.
The screen originally didn't come from a sink faucet.
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  #12  
Old 11-10-2004, 11:24 PM
justwannano justwannano is offline
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So what did it come from?

Are you sure you really need it?
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  #13  
Old 11-11-2004, 05:30 AM
Colophon Colophon is offline
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Quote:
Originally Posted by Roches
Alcohols, including rubbing alcohol, are relatively weak acids compared to mineral acids (sulfuric, hydrochloric, etc.) and even organic acids (acetic, citric, etc.)...
Alcohols are less acidic than water, let alone mineral acids - they have pKa values from 15 to 18.

Isopropyl alcohol has a pKa of 17.1. (Water = 15.7)

I can't think of a single metal you'd find around your house that would react significantly with isopropyl alcohol, let alone dissolve in it. From that last linked site:
Quote:
Isopropyl alcohol is registered as an antimicrobial, bactericide, fungicide, and virucide. It is used for sterilizing and disinfecting surfaces in hospitals, dairy farms, food processing plants, eating establishments, and in household dwellings. Isopropyl alcohol is also registered for use as a topical disinfectant in animal areas in and around the house, in veterinary institutions, farm structures, poultry areas, and in hatcheries and zoo animal premises. It is registered for use in barbershops for cleaning hair cutting and styling instruments and equipment.
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  #14  
Old 11-11-2004, 10:09 AM
Wikkit Wikkit is offline
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In the other direction, copper will act as a catalyst for methanol, and I would think isopropyl as well. So your brass screen may "dissolve" rubbing alcohol.
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  #15  
Old 11-11-2004, 11:42 AM
Colophon Colophon is offline
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Quote:
Originally Posted by Wikkit
In the other direction, copper will act as a catalyst for methanol, and I would think isopropyl as well. So your brass screen may "dissolve" rubbing alcohol.
A catalyst for methanol to do what?
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  #16  
Old 11-11-2004, 11:50 AM
Q.E.D. Q.E.D. is offline
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Quote:
Originally Posted by Colophon
A catalyst for methanol to do what?
Apparently to manufacture it. This article (Warning: PDF document) describes the Lurgi low pressure methanol synthesis process. In it, hydrogen, carbon monoxide and carbon dioxide are made to react in the presence of a copper-based catalyst.
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  #17  
Old 11-11-2004, 01:01 PM
Wikkit Wikkit is offline
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Huh. Not suprising that it can be used in the reverse process, but I meant that it acts as a catalyst to break methanol down into water and CO2. As does platinum. If you heat a ball of very fine copper wire to glowing, then suspend it in methanol fumes (like over an open bottle of methanol), it will continue to glow as the methanol breaks down (exothermically).

Platinum is even better at it. You can buy self-igniting lighters that run on methanol. They have a tiny bead of platinum sponge suspended over the fuel source. As soon as the lighter is opened, the platinum bead heats up to the point of igniting the methanol.
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