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Subject: TeasTime solubility program

TeasTime solubility program

From: Walter Henry <whenry>
Date: Tuesday, July 25, 1989
If you are put off by using carbon tet, you might try an alternative or
blend.  Carbon tetrachloride has the following fractional solubility

    Dispersion:         85
    Polar:              2
    Hydrogen Bonding:   13

which can be matched reasonably well by o-xylene  (83,5,12) [from here
on, fractional parameters will be in the form (D,P,H)] or ethyl benzene(
87,3,10).  Practically speaking, you would substitute xylenes for
0-xylene, but the numbers don't change much.  Both of these solvents
have NFPA health ratings of 2 and would be a big improvement over carbon

However, if you want some other options that either match the parameters
of carbon tetrachloride more closely or are safer, any of the following
blends should work:

             Solvent                                    Fractional
              Blend                                     Solubility
              -----                                     Parameters

                                                      D      P      H

71.3% n-pentane and 28.7% n amyl alcohol            (84.49, 3.73, 11.78)
69.0% n-pentane and 31.0% cyclohexanol              (84.49, 3.72, 11.79)
79.5% n-pentane and 20.5% propylene glycol          (86.49, 3.07, 12.29)
71.3% n-hexane and 28.7% n amyl alcohol             (84.49, 3.73, 11.78)
69.0% n-hexane and 31.0% cyclohexanol               (84.49, 3.72, 11.79)
79.5% n-hexane and 20.5% propylene glycol           (86.49, 3.07, 12.29)
71.3% n-heptane and 28.7% n amyl alcohol            (84.49, 3.73, 11.78)
69.0% n-heptane and 31.0% cyclohexanol              (84.49, 3.72, 11.79)
79.5% n-heptane and 20.5% propylene glycol          (86.49, 3.07, 12.29)
81.4% odourless solvent and 18.6% propylene glycol  (86.13, 3.60, 11.95)
95.9% ethyl benzene and 4.1% methanol               (84.64, 3.79, 11.57)
95.3% ethyl benzene and 4.7% ethanol                (84.59, 3.71, 11.70)
94.8% ethyl benzene and 5.2% one-propanol           (84.57, 3.67, 11.76)
94.7% ethyl benzene and 5.3% two-propanol           (84.57, 3.69, 11.74)
94.5% ethyl benzene and 5.5% one-butanol            (84.56, 3.66, 11.77)
94.4% ethyl benzene and 5.6% two-butanol            (84.60, 3.73, 11.68)
94.0% ethyl benzene and 6.0% n-amyl alcohol         (84.53, 3.60, 11.87)

All of which gives me a chance to toss in a plug for TeasTime. TeasTime
is a computer program that I wrote for just this sort of situation.  If
you specify a set of fractional solubility parameters (or select one of
the solutes (mostly resins) that TeasTime knows about), the program will
reason backwords to determine solvent blends that will match those
parameters, thus saving you lots of ruler-and-graph-paper time.  You can
customize the TeasTime database (eg so that it reflects only those
solvents you own, or like to use).  Currently TeasTime only determines
blends of two solvents, but in a future version will allow mixtures of
three solvents (which gives, for all practical purposes, complete
coverage of the real-world portion of the Teas chart).

TeasTime will run on any IBM-PC or compatible.  You will probably want
to run it on the fastest machine you have available.  There is not yet a
Macintosh version, but John Burke (Oakland Museum) and I are talking
about porting it over.  Oh yeah, almost forgot, the program is public
domain, absolutely free, and is very easy to use (assuming you
understand a little about solubility and using teas charts).  So, if
anyone would like a copy, just let me know and I'll send you a disk.

                  Conservation DistList Instance 2:21
                  Distributed: Tuesday, July 25, 1989
                        Message Id: cdl-2-21-004
Received on Tuesday, 25 July, 1989

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