Sodium hydroxide diffusion coefficients

The diffusion coefficients of spin, of sodium and potassium hydroxides of different cone., between 12° and 13 5°, are, according to J. Thovert 38... 

Water, sodium ion, and hydroxide ion concentrations have been measured within the membrane phase as a function of bulk caustic solution concentration and temperature. These internal membrane concentrations are important because of their influence on the membrane polymer morphology, structural memory, plasticity and the resultant effects on its internal resistance, viscoelasticity and material transport. In addition, the self-diffusion coefficient of the sodium ions in various Nafion membranes has been measured as a function of temperature and external caustic concentration... 

FIG. 6 Dependence of polyion fast diffusion coefficient Df on degree of neutralization a for poly(methacrylic acid) salt-free aqueous solutions. Mw = 30,000, polymer concentration c = 36.6 g/L. Polymer chains were ionized by neutralization with sodium hydroxide. (Adapted from Ref. 8.)... 

From the temperature coefficient of the rate constant, the activation energy for the Claus reaction over the Chromosorb-A was determined to be 25.0 kcal/mole and for the sodium hydroxide-loaded Chromosorb-A it was about 15 kcal/mole. The apparent change in the slope of the Arrhenius plot might indicate some transition in the controlling mechanism. Over the cobalt-molybdena catalyst, the Claus reaction appeared to be diffusion-controlled with an activation energy of 5.5 kcal/mole (2). 

Figure 14.24 Plot of the mean effective diffusion coefficient vs extent mixing for the sample MA6 from Figure 14.23, to which one equivalent of ammonium, sodium or barium hydroxide, based upon titratable acid groups, was added to the dispeision prior to film formation. The annealing temperature was 100 °C...

Comings and Briggs (20) studied the extraction of several solutes between benzene and water. For the extraction of benzoic acid, where the distribution favors the benzene, the major resistance to diffusion lay in the water phase. Addition of sodium hydroxide to the water reduced this resistance by causing a rapid chemical reaction, increased the mass-transfer coefficient, and made the effect of benzene rate on the over-all coefficient more pronounced, as would be expected. Similar experiences were obtained in the case of extraction of aniline, but in the case of acetic acid results were contrary to what was expected. The data apparently could be interpreted in terms of Eq. (10.11), with = 0.45 — 0.55,7 = 0 — 0.1, ri = 0.40 — 0.55, T = 0.45 — 0.55. Brinsmade and Bliss (13) extracted acetic acid from methyl isobutyl ketone (core) by water (w all). By making measurements at several temperatures, they were able to investigate the influence of Schmidt number on the rates and by graphical treatment of the data obtained values of the constants of Eq. (10.11) as follows j8 = 1, = 7 = 0,... 

Diffusion coefficients of several acids and of sodium hydroxide in polyamide 6 at 25 °C [657]... 

Diffusion coefficients for cellodextrin alditols (d.p. 1—5) were found to be 22% less in 0.32M sodium hydroxide than in water. The alditols had slightly lower rates of diffusion and higher coefficients of friction and Einstein-Stokes hydrodynamic radii in water than the corresponding cellodextrins. 

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