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Cheap high-density liquid

  1. Mar 12, 2011 #1
    So I am trying to find a liquid at room temp., preferably with a low viscosity, non-toxic and non-acidic, that has a specific gravity greater than 1.5 and is fairly cheap. Tall order?

    I have done a little research and my best bets seem to be Copper Sulfate Pentahydrate, Zinc Chloride, or possibly Sodium Hydroxide(but thats caustic). NaCL solutions seem to max out around 1.2-1.3, and sugar solutions around 1.4 at room temp.

    I think Copper Sulfate might do the trick, but I cannot figure out what is the highest possible density achievable around room temperature. The specific gravity is 2.284 but it's solubility is pretty low, maybe 300-500g/L?

    Does anyone know this off-hand or have other chemical suggestions?
    Last edited: Mar 12, 2011
  2. jcsd
  3. Mar 12, 2011 #2
    You know that Copper Sulfate is toxic.
  4. Mar 12, 2011 #3
    Yes, but I'm not going to be taking a bath in it or be drinking it. I mean, I don't want something as toxic as mercury. I basically need something that I can survive through if it spills. It will take more than copper sulfate to kill me!

    Seriously, though, the non-toxicity is just an added bonus.
  5. Mar 12, 2011 #4

    Chloroform its density is 1.483 g/cm3
  6. Mar 12, 2011 #5
    It's really not much denser than sugar solution. Sugar water doesn't make you pass out if you breath in vapors either. Might be fun though.
  7. Mar 13, 2011 #6
    Can you clarify the purpose even offer the assistance required
  8. Mar 13, 2011 #7


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    highly water soluble tungstates such as sodium metatungstate have been traditionally used as high-density liquids. you can get above a specific gravity of 3 easily if i recall correctly using this kind of solution.
  9. Mar 13, 2011 #8
    True again, but sodium metatungstate goes for like $800/kilo. There is just no pleasing me right?

    The idea is to create a low-cost & fairly safe pressure equalizer with a column of fluid. A denser fluid means I can achieve the same pressure head with a shorter column. I don't want the viscosity to be very high because the column may need to rise and fall, and I want that to happen relatively quickly.

    It may need to have a volume of about 5-10 liters if I use water.
  10. Mar 13, 2011 #9


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    no. sodium metatungstate is much cheaper than that. that is probably the price from redistributors like Sigma or Alfa selling small quantities.

    some data from a distributor:

    for example, 50 kg can be had for $1k from this american distributor http://www.alibaba.com/product-free/100628785/Sodium_Tungstate.html which is only $20 per kg

    and much cheaper from china and india. also much cheaper if you buy in ton quantities.

    but it sounds like you don't need nearly this much. there are no shortage of redistributors who i'm sure would be happy to quote you for, say, 10-20kg or so.
  11. Mar 13, 2011 #10
    No kidding! I've seen alibaba come up in a lot of searches but it never looked that legitamate. I'll have to look into this.

    Still though, does anyone know the max density of copper sulfate pentahydrate solution at room temp. I'm not a chemist and I couldn't find it anywhere. Copper sulfate is pretty easy to obtain.
  12. Mar 13, 2011 #11
    Try googling barium sulfate.It has a high density and amongst other things is used in barium meals where the patient drinks some of it.
  13. Mar 13, 2011 #12
    It's insoluble in water and alcohol...
  14. Mar 13, 2011 #13
    Barium sulFIDE is soluble but..."BaS is quite poisonous, as are related sulfides, such as CaS, which evolve toxic hydrogen sulfide upon contact with water. "
  15. Mar 13, 2011 #14


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    Staff: Mentor

    Solubility around 20g/100g of water, density around 1.2 g/mL. It doesn't want to get much higher than that at room temp. Solubility goes up for higher temperatures, so I guess the density of boiling solution can be much higher, but it won't help.
  16. Mar 13, 2011 #15
    golden syrup,treacle,tomato sauce,non drip paints,long alkane or kenes eg fuel oil.
  17. Mar 13, 2011 #16
    Too bad about copper sulfate...thanks for the info though (love the hair).

    golden syrup/Treacle=slow as molasses+specific gravity of 1.4ish?
    tomato sauce and paint will just gum everything up

    I don't know any fuels or fuel oils with densities much greater than water. Maybe I just am not looking hard enough?
    These are all generally very viscous though which is the opposite of what I am looking for.
  18. Mar 13, 2011 #17
    Why have you not considered mercury? I'm guessing its either for safety or financial reasons.
  19. Mar 13, 2011 #18
    Yes exactly. Both are issues really, even though I would only need 1/13th the volume compared to if I used water.
  20. Mar 13, 2011 #19


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    Staff: Mentor

    Carbon tetrachloride? Perhaps not the safest substance in the world, but with reasonable care can be acceptable.
  21. Mar 13, 2011 #20
    I suppose keeping a vat of molten Platinum is out of the question?...

    Kidding aside, is there a reason that Glycerol wouldn't work? It's not 1/13th, but it's 1.261 g/cm³ compared to water, it's cheap, and it won't kill you.
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