Sciencemadness Discussion Board

Drain cleaner

darkflame89 - 14-3-2004 at 01:47

I was expermienting with my drian cleaner today. I noticed that there were pieces of aluminium metal within the sodium hydroxide powder. What is the use of the aluminium powder inside? I know that the aluminium reacts with NaOH to form sodium aluminate., but what's the use?


Another thing that i saw today is the laundry detergent by the name "Vanish O2" It contains sodium percarbonate, sodium carbonate, dipropylene glycol. It supposedly gives off O2 gas in solution. What sort of reaction happens here?

Saerynide - 14-3-2004 at 04:15

What brand of draincleaner is that with the NaOH? I've been looking for one!

Mumbles - 14-3-2004 at 11:01

Crystal Draino has the aluminum flakes in it. The prills are also colored blue for identification I guess.

I honestly have no clue as to their purpose. Maybe it's supposed to react under the clog and break it up with presure? Maybe it protects the pipes.

The_Davster - 14-3-2004 at 11:28

Could it be that the sodim hydroxide when in solution will react with the aluminum making hydrogen gas which would some how break up the clog?

Saerynide - 14-3-2004 at 13:00

Yeah I know draino was good, but were darkflame89 and I live right now doesnt have draino :(

darkflame, you must gimme the brand! :D

hodges - 14-3-2004 at 13:44

The aluminum serves to heat up the solution during reaction so as to better melt through the clog.

Drano also contains some NaNO3, which causes NH3 to be produced instead of hydrogen during the reaction. I guess the product engineers feel NH3 is safer than H2 inside.

BromicAcid - 14-3-2004 at 14:48

Take the ideas in this thread and mix them together to get the answer, the aluminum serves a two fold purpose, to heat up the reaction mixture, and to agetate the mixture with H2 formation so that the hydroxide solution at the bottom has a incentive to move to the top and new hydroxide solution goes to the bottom.

darkflame89 - 15-3-2004 at 01:39

I dunno 'bout this nut here goes the name of the drain cleaner: Kiwi Dranex Pipe cleaner.

I found out about it after i saw my mum use it. It gave off a smell quite similar to that of ammonia. It turned the red litmus paper blue, and i found that pieces of aluminium at the bottom of the solution giving off bubbles.

Saerynide - 15-3-2004 at 02:06

Ahhh... That stuff :D My mom used it and it stunk up the house so bad I almost puked (literally!). It didnt occur to me that it would be NaOH.

Companies never label their ingredients here.... Must be a conspiracy to keep people from abusing their contents :mad:

Edit: You cant even begin to understand how much I thank you. :D

[Edited on 15-3-2004 by Saerynide]

darkflame89 - 16-3-2004 at 00:34

I hope it is sodium hydroxide. Keep me updated 'bout it. Cause i got some doubts about it after i dissolved in water, it did not cause a measurable amount of increase in temperature.

NaOH dissolving in water is supposed to give off lots of heats, and splash about and such.

I was doing the saponification reaction at about afternoon, i tried to add some of the drain cleaner to the cooking oil i have at home. I added some Dettol as a catalyst to the mixture( I read in the book, i dunno about how good this catalyst is supposed to be). I waited for a day and the reaction this not happen very fast. Except for a lot of particles suspended between the oil and the NaOH.

Ah, and i am trying to obtain sulphuric acid from my dad.

One thing i agree with Saerynide is that the the companies never put a concise label of the chemicals present in their product.

Saerynide - 16-3-2004 at 02:23

I wonder what keeps it from reacting violently with water... Is it hygroscopic like real NaOH?

If its crappy, we might as well make our own NaOH (but it takes forever!! :()

Btw, Im trying to make my own H2SO4 :D

Edit: Do you know how Dettol is supposed to be a catalyst?

[Edited on 16-3-2004 by Saerynide]

darkflame89 - 16-3-2004 at 05:25

No idea, the original catalyst was supposed to be thymol, but the book said experiment with Listerine, phenol, and Dettol. I don't have thymol, so i used Dettol. I guessed the above examples of possible catalysts are somehow a variation of phenols.

MSDS

Magpie - 16-3-2004 at 20:08

I suggest that if you really want to find out what is in a commercial product find the MSDS. Even janitors have the right to know what hazards they will be exposed to. This is also invaluable when they have to call the poison control center.

thunderfvck - 16-3-2004 at 22:42

I recently bought some NaOH at reno depot. It's a drain cleaner, I found it where they kept their HCl and drain cleaners (the powerful bagged ones). It looks relatively pure. No blue coating, just white pellets. Although most of it is a bit dusty. But it's pure white. It came in a small white container, reads NaOH on the back. I'm Canadian so we don't have any red devil lye, and draino just looks too impure for my liking, so I was very excited when I found this. I'll do a melting point when I get the proper tools via ebay, which will take some time, but I will post the results if you're interested.

How much drain opener did you add to the water to test its exothermic abilities? I've done this in school with pure NaOH and I don't recall it splashing and getting extremely hot. I added some of the drain opener I have to water, quite a bit of it mind you, and the water got pretty hot. I wonder if determing the enthalpy of solution is a reliable test to test the purity of my NaOH.

Esplosivo - 17-3-2004 at 03:02

The NaNO3 in the drain cleaner reacts with a mixture of Al and NaOH to produce Ammonia. This generates heat, and ammonia which is also caustic and reacts with a many metals (such as Al, Zn, Cu), especially when hot.

I doubt it can generate pressure as much as the hydrogen produced since ammonia is extremely soluble in water. If I remeber correctly 8000 volumes of ammonia dissolve in 1 volume of water, ie around 89.9 g/100cc @ 0ºC. I suppose that the role of ammonia is as another caustic agent.

The solubilty of NaOH is high, 111 g/100 g of water. If less quantity of NaOH is added to the same amount of water the temperature rise will not be very high. Actually the enthalpy of hydration of NaOH causes the water to heat up, but I have never seen it boil.

Esplosivo - 17-3-2004 at 03:20

Saerynide, I suppose that the role of dettol in not that of a catalyst but of an emulsifying agent. Oil and NaOH in conc. solution will not mix well if not stirred contsantly. Dettol will probably aid in emulsification. Other emulsifiers might be incompatabile since they have low boiling points or might react with one of the reactants in the mixture.

You also named thymol and phenol, which have a -OH groups attached to a hydrophobic side chain. I suppose that these would therefore act as emulsifiers too.

[Edited on 17-3-2004 by Esplosivo]

Saerynide - 17-3-2004 at 03:29

Ah, I see.

I remember dropping NaOH into water at school and the temperature of the solution reached about 96 C. So, almost boiling I guess. I have never seen it boil before either, but I've always heard that it happens. I guess they mean when you ahve HUGE quantities of NaOH.

darkflame89 - 18-3-2004 at 00:28

I have cheacked up on the phenol as a sort of catalyst. According to my book, its says that a metal hydroxide will react with phenols to from a metal phenoxide. Then I think the sodium phenoxide from the reaction will furthur react with fats to from phenol again and soap. I dunno if this reaction has a lower reaction time.

Incidentally, the book also says that if a alkali metal is to react with phenols, it also forms the metal phenoxide.

I shudder to think what a beaker with oil storing a piece of sodium will become if someone had accidentally poured phenol into. The whole beaker might solidify over to form soap.

Regarding the the Dettol acting as a emulsifying agent, I am not so sure about it.

Esplosivo - 18-3-2004 at 08:01

After taking a look to the MSDS of both thymol and phenol one can see that strong bases are incompatabile with them. NaOH is surely strongly basic. I cannot find any valuable info about the action of thymol.

About the sodium phenoxide. This is surely more reactive than the phenol itself, such that it is used to prodeuces esters of phenol, but how should it react with the fatty acids in the oil?! I do not think that the phenoxide ion will 'donate' the Na without reacting with anything else, unless its role is to form an 'unstable' sodium ion. This ion can probably be lost to a fatty acid and the phenoxide ion might 'absorb' another one from the NaOH solution, though I suppose this is not feasible.

MSDS for thymol: (note that organic materials and strong bases are incompatable, not only to be avoided)
http://ptcl.chem.ox.ac.uk/MSDS/TH/thymol.html

darkflame89 - 20-8-2005 at 02:08

Sorry, for bringing up an old and pretty much dead thread, but I require help again. Instead of posting again, I figured I'll just post in my old thread.

I need to separate the NaOH and aluminium pieces as I want to melt the NaOH electrolyse it to get the sodium. The tricky part is that once it dissolved in water, the alumnium will rapidly dissolve.

A physical way of separating them both in solid state would be preferred over than a method that requires several steps of chemical reactions.

If that thing really contain sodium nitrate, it would be nice too to separate the nitrate from the hydroxide.

Another puzzling matter, if that cleaner contained purely only NaOH and aluminium, then attempting to melt the mixture is dangerous, or quite suicidal. But if there were NaNO3 present, what would happen? A eutectic would form? Checking the excellent eutectic salt website provided by BromicAcid, I found a plausible eutectic:
NaNO3-NaOH 18.5-81.5 258 C
NaNO3-NaOH 41-59 266 C
Other interesting stuff:
NaCl-NaNO3-NaOH 3.6-18.3-78.1 242 C
NaCl-NaNO3-NaOH 4.2-40.2-55.6 247 C

The_Davster - 20-8-2005 at 06:30

One of my first molten hydroxide electrolysis experiments was with an unpurified draincleaner containing NaOH, NaNO3 and Al. I just melted the draincleaner over a burner and then electrolyised it. This is before I really knew what I was doing and I used a 200mA 12VDC power supply so of course I got no sodium. But once I had gave up I poured out the molten hydroxide, and in the bottom of the can I had melted it in was a pile of the Al pieces stuck together. Was it safe? Probably not, but once I had poured off the molten hydroxide I had the hydroxide and nirate separate from the Al. I am also not sure how reproducible this would be. So perhaps try on a small scale first melting some of the draincleaner and pouring off the molten hydroxide/nitrate from the Al.

neutrino - 20-8-2005 at 08:34

I don't know if something this simple would work, but shaking a mixture of particles with different sizes causes the particles to separate by size (the biggest ones go to the top.) The densities of Al and NaOH (2.7 and 2.13, respectively) may or may not help here.

[Edited on 20-8-2005 by neutrino]

12AX7 - 20-8-2005 at 18:29

Electrostatic seperation would be good here. In a DRY chamber (NaOH is nice and hygroscopic!), pass the drain cleaner over a charged plate or under a brush or something (on a conveyor belt), then it tips over the end and falls between two charged plates.

A second pass on the white stuff might tease nitrate from hydroxide, too.

Tim

darkflame89 - 21-8-2005 at 00:54

The electrostatic precipitator idea is nice but cannot work in Singapore. Singapore has a high humidity and therefore render electrostatic devices useless. It is so humid that if I place the sodium hydroxide powder out in open air, the sodium hydroxide will "dissolve". No surprises, as sodium hydroxide is hydroscopic, and there is plenty of water in the air. If a huge container could be constructed to hold such device as well as provide a dry atmosphere, it would be pretty much be impractical.

About rogue chemist's method, you melted the mixture without anything? No explosion?
Sure its safe? Well, if it is, I'll try to melt some and see if I can separate them. You mentioned that the molten hydroxide and nitrate came off, which means the sodium nitrate melted as well?

On neutrino's method, yeah, I've heard of that one before, seen a demo on it. You shake a bottle of sand with a ping pong ball embedded in it and after a while, the ball pops out. Not sure whether this will work for the sodium hydroxide and aluminum though, will try it later and see. I think the particle ratio is not obvious enough.

Anyway, I found out something, silly me, the reaction of nitrates with nascent hydrogen generated by aluminium and sodium hydroxide can only take place if there's water around.

Edit: Seems like I was overly paranoid about the hydrogen evolution from aluminium in molten sodium hydroxide. Quote from BromicAcid in the Sodium! post..
Quote:

Aluminum containers were used for the sodium hydroxide fusions in this work. When aluminum is immersed in fused sodium hydroxide, gas evolution from the surface of the metal occurs but this lasts
only a few seconds. It is proposed that the protective coating consists of a layer of an insoluble sodium aluminate since if the metal is removed, washed and then returned to the melt, the brief attack occurs again.


[Edited on 21-8-2005 by darkflame89]

12AX7 - 21-8-2005 at 09:23

Quote:
Originally posted by darkflame89
The electrostatic precipitator idea is nice but cannot work in Singapore. Singapore has a high humidity and therefore render electrostatic devices useless. It is so humid that if I place the sodium hydroxide powder out in open air, the sodium hydroxide will "dissolve". No surprises, as sodium hydroxide is hydroscopic, and there is plenty of water in the air. If a huge container could be constructed to hold such device as well as provide a dry atmosphere, it would be pretty much be impractical.


Heh heh! I know the feeling. When I'm working with hydrochloric acid in the basement, after pouring a jar's worth the whole room is now filled with smoke!

Tim

chloric1 - 21-8-2005 at 09:51

wow Tim I have only experienced this on the very muggiest of days. We just got a Canadian airmass and our humidty is about 39%. Sweet! Works in favor of chemistry. This is in contrast to a dewpoint of 75 fahrenheit yesterday. Man that was rough!:( I could rinse off a beaker with not so cool water and it would fog up instantly. Could not tell if I did an adequate job of cleaning!

[Edited on 8/21/2005 by chloric1]

12AX7 - 21-8-2005 at 19:11

Well the thing with our basement is it's an old masonry foundation that sits right in the dirt, so it's always basically 90% humidity. :o Outside, today was beautiful though :)

Tim

Back on topic!

Element - 29-4-2010 at 13:55

Alright, so I've got the same problem:
My draino cleaner contains NaOH, NaNO3, NaCl and aluminum chips (so said my MSDS, I didn't open the bottle yet, as I know NaOH is hygroscopic.)

Unfortunately, there seems to be no way we could easily separate those compounds by selective precipitation, they all dissolve completely in water (and I guess their solubilities in other solvents would be the same between themselves).

Maybe adding another cation could work... I'm still vaguely looking into that, but nothing seems to be very effective. Would there be any chemical reaction or separation process to isolate NaOH and NaNO3 (or only one of those)?

I've thought a bit of electrolysis... maybe oxydizing OH- into H20 and O2 would get rid of NaOH (but then again, I'd like to keep it!), leaving me with a NaNO3/NaCl solution... but that doesn't seem to be the most efficient way, nor the easiest (electrochemistry hates chemists)

Thank you!
Christian

12AX7 - 29-4-2010 at 18:12

Mechanical seperation is easiest. Most types have a flake sort of NaNO3, which is easily blown away with air (dry air is a must!). The aluminum can be seperated by gravity, or eddy current repulsion (easy for me to say, I've got an induction heater).

Ba(NO3)2 is handy for isolating nitrates, but that's if you have an excess of nitrate already. It's not going to work well with hydroxide or carbonate around, since those will precipitate instead.

Tim

Element - 20-5-2010 at 19:29

Thanks 12AX7!

Well, I've tested it up and for further reference about this particular product (Crystal Draino):
The blue "balls" are most probably the NaNO3, as it is weakly basic and the blue "salt" (there really are three distinguishable components in there) should be NaOH as it is extremely basic (very very few of it in a test tube turned water to pH 13~14). And then obviously there are the aluminum shards. As for the NaCl, I have no idea... probably mixed up with one or the other... it's supposed to be about 10-15% anyway, so it's no very big deal.

Well, those are only my humble observations. Anyway I stand no better as this would take a veeery long time to separate little balls from salt (plus, they tend to stick together, probably because of the humidity). As to "blow away", I don't really understand what you mean... Or at least, I can't think of how I'd separate it with household equipement! I'll still "work" on that... Maybe I could just add a weak acid, so to get rid of NaOH... But then again, I first bought it FOR the NaOH :P Both this and NaNO3 would be cool to obtain really.