Resolving the Mystery of Aqueous Solutions of Tertiary Butyl Alcohol

Abstract

We have resolved a long-standing issue in the discussion on the origin of the mesoscale inhomogeneities observed in aqueous solutions of tertiary butyl alcohol (TBA). We have shown that the formation of stable mesoscale particles (of about 100 nm in size) can be triggered by the addition of trace amounts of propylene oxide (an impurity expected to be present in all commercial samples of TBA) to a solution, which was previously filtered at a low temperature to remove these inhomogeneities. We hypothesize that these particles are aggregates of mixed clathrate-hydrates that are formed through the stabilization of fluctuations of the intrinsic structure in TBA aqueous solutions by the clathrate-forming ability of propylene oxide.

Possible Further Evidence for the Thixotropic Phenomenon of Water

“…In some systems the domain structure appears stable, whereas in others a very slow process of domain fading out was observed. Hence, the large-scale inhomogeneities are much larger than the dimensions of individual molecules, typically on the order of 100 nm [74,77,78]. Solutions of ordinary low molar mass compounds and mixtures of freely miscible liquids, according to a vast literature on LLS measurements, may evidently not be as homogeneous as previously thought.…”

“…The features of EZ water, in our opinion, also play an important role in the development of the thixotropic phenomenon that could be further confirmed by large-scale inhomogeneities found in aqueous systems. Literature indicating large scale inhomogeneities in aqueous solutions is accumulating, with emphasis on static and dynamic laser light scattering (LLS) measurements [69][70][71][72][73][74][75][76][77][78][79][80]. A wide variety of other experimental techniques may confirm that in aqueous under-saturated strong electrolyte solutions, the ions are not homogeneously distributed [63,[81][82][83][84][85][86].…”

Experiments on tracer diffusion in aqueous and non-aqueous solvent combinations

“…1, 2,5,8,19,[34][35][36] Following classic hydrophobe behavior, 5, 37 the amphiphilic molecules tend to cluster together with their hydrophobic portions shielded from the water. For MR diffusion, starting with pure water, addition of the amphiphile forms a first solvent shell up to a certain amphiphile concentration, beyond which no additional amphiphile can be added to the shell.…”

“…1, 3,[7][8][9][10][11][12][13][14][15][16] The change with concentration of the diffusion coefficient of either water or the organic molecule has provided insight in a large number of experimental and simulation studies. 4,9,10,[17][18][19][20][21][22] In many cases, however, one is concerned with the motion and reactions of a solute molecule within the solvent combination.…”

“…4,9,10,[17][18][19][20][21][22] In many cases, however, one is concerned with the motion and reactions of a solute molecule within the solvent combination. 7,8,[23][24][25][26][27] In the present effort we wish to study the changes with solvent concentration of the diffusion of a largely (though not completely) hydrophobic tracer molecule comparable in size to many drug molecules.…”