Experiment using Murphy's Oil Soap to Indicate Hardness.

Discussion in 'Water Softener Forum, problems, installation and r' started by Reach4, Nov 15, 2013.

  1. Reach4

    Reach4 Well-Known Member

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    water_soap.jpg
    I had read about using liquid Castile soap to test water hardness. I was not looking for a numeric result here, but I was looking for an indication as to whether water softener cycle time should be shortened. Testing was not well controlled.

    1. Glass on right... I put untreated well water (hardness in the 30s) into a clear plastic glass. I dropped a small drop Murphy's. It floated due to surface tension. I drizzled a bit more. There were very interesting and artistic patterns initially. The water was still swirling a bit from being filled. As it sat, the whole content became milky.

    2. Middle glass. I put softened cold water from the tap tested to about 1 or 2 grains hardness with Hach 5B. I was disappointed to see some milky trails. The picture was taken about 20 hours later. A hovering ring had developed... it shows only as a line in the side photo, but it is a heavier version of the ring shown in the left glass.

    3. I decided to check the validity of the testing. I put distilled water into another glass. I put in more soap than in the previous tests-- maybe 6 drops equivalent, although I just put it in as a bigger bit. It sank to the bottom, with just a little initial cloudiness trail. The next morning about 19 hours later, a sharp hovering ring was in the glass. From the top, the ring is pretty much circular and centered in the glass.

    So as a test for hardness, this could be developed to be more useful. Perhaps a test where the soap is dropped in with a dropper would be more meaningful and repeatable. Maybe a 2:1 dilution with distilled water would be better, because the Murphy's is pretty viscous.

    Maybe some student would want to develop this as science fair project.
  2. DonL

    DonL Jack of all trades Master of one

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    If it does not Blow up then not likely. Dry Ice is funner.

    You need to record / maintain the temperature for best results.

    Always have the proper input data for your formula to work as expected.


    Have Fun.
  3. ditttohead

    ditttohead Water systems designer, R&D

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    Location:
    Ontario California
    http://www.wcponline.com/pdf/1203Michaud.pdf

    Check out this article. While a simple soap test is not scientific, it is surprisingly usable. My biggest surprise using the old soap test was a few months ago during a training seminar. I had three vials, 1 with soft water, less than 5 ppm, 1 with 21 grains hard water, and the third with 21 grains water run through an anti-scale media (salt free conditioning), the stuff made in Germany. (brand name withheld)

    The soft water had the expected results, lots of bubles.

    The hard water was unable to produce any bubbles.

    The anti-scale had a very noticable amount of bubbles, no where near as much as the soft water, but a lot more than the hard water.

    Conclusion, I was susrprised the anti-scale media had any affect. I have been able to repeat these reults on multiple occassions since then. I am still not convinced that anti-scale will take over the salt softener market, but it does give me a lot more confidence than I had prior to this very simpe test method. I am not much of a fan of this test method, but it is a lot of fun and some useful information can be garnered from it.

    This is one of the things I like most about this forum, a lot of interesting ideas get tried and dicussed by people with the intention of furthering their knowledge and understanding of water treatment.

    Let us know how your testing ideas proceed.

    FYI, the old soap test was an in-house demo to show the benefits of soft water. The salesman would put your water through a small amount of softening resin and fill two bottles with soft, and hard water. Add a drop of soap to each and shake. Voila! Soap bubbles, no soap bubbles.
  4. Reach4

    Reach4 Well-Known Member

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    Last edited: Nov 15, 2013
  5. ditttohead

    ditttohead Water systems designer, R&D

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    Location:
    Ontario California
    Agreed, I have worked with these medias for many years and have found many applications where they have worked well, in other applications, they seem to do nothing. We have also found that they are highly sussceptible to copper fouling, iron and manganese must also be removed prior to this media.
  6. Noyzee1

    Noyzee1 New Member

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    Location:
    SoAz
    Hello,
    Just curious- why Murphy's Oil Soap and not some other one?
    Any surfactant should show differences in the water. Is it the oil?
    Cheers,
    JIM
  7. Reach4

    Reach4 Well-Known Member

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    I had that soap. It is a soap although Wikipedia says it has other things too. http://en.wikipedia.org/wiki/Murphy's_oil_soap It is made with some vegetable oil that I don't know, whereas Castile liquid soap is made with olive oil. I was thinking about ordering some, but I decided to try what I had.

    So why does the hardness react with the soap to produce a visible cloud? https://en.wikipedia.org/wiki/Soap_scum seems to address the reaction.
  8. Noyzee1

    Noyzee1 New Member

    Messages:
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    Location:
    SoAz
    Maybe we have TWO separate issues: 1) More bubbling with soap in soft water as opposed to hard, & 2) Oil in Murphy's causes white streaks because the soap turns the grease white. I think that the soap isolates the grease due to emulsification (http://chemistry.about.com/od/cleanerchemistry/a/how-soap-cleans.htm).
    This allows the oil/grease to be isolated and washed away.
    Cheers,
    JIM
  9. Reach4

    Reach4 Well-Known Member

    Messages:
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    Location:
    IL
    I have not tried bubbles or shaking yet. My distilled sample with extra soap has turned somewhat cloudy. I will want to use measured amounts of soap in any future tries. The raw well water glass is still milkiest, but it has significant white precipitate at the bottom of its glass.
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