Crystallization of p,p'-DDT from Binary Melts

Abstract

The second order rate constants for the reaction of nitroethane with ammonia, methyl-, dimethyl-and trimethylamine in water at 0 and 5.2°are reported.2. The values of the rate constants at 00 are calculated from equilibrium data for the reaction of ammonium ion, methyl-, dimethyl-and trimethylammonium ions with the anion of nitroethane.3. The heats and entropies of activation for the above reactions are computed.4. The interpretation of the data indicates that the activated complex is not as strongly solvated as the product ions but more solvated than the reactants.5. The decreased base strength of trimethylamine appears to be due to the decreased solvation energy and hence increased reactivity of the trimethylammonium ion.Evanston, Illinois

Thermal Activation of Attapulgus Clay - Effect on Physical and Adsorpptive Properties

“…Fuller's earth is used in the reclamation of used lubricating, turbine, and transformer oils (23). Georgia-Florida fuller's earth also finds use in the petroleum industry as a catalyst or catalyst support (4), in the treating of gasoline by the Gray process (46), and in the desulfurization (2,15), polymerization (18), depolymerization (8,9), and cracking of hydrocarbons (15). In the sugar industry, Attapulgus clay can be used for pH adjustments of sugar liquors (30).…”

Application of Fusion Methods in Chemical Microscopy

“…In particular, the properties which affect the rate at which molecules become oriented on and enter into a crystal front, can be studied by studying the effect of variations in molecular shape, size, polarity, etc., on rate of crystallization. It has been found by this means that the rate of crystallization of a given compound in a binary mixture may be more rapid than in the pure state (2). The compound, p,p'-DDT, for example, will grow almost 100 times as rapidly in mixtures containing 20% Cello-Bolve as in the pure state at the same temperature.…”

Light Microscopy.

“…Reimers (111) discusses the advantages and limitations of thermal analysis. Fusion methods have received considerable study' by McCrone and his collaborators (58,59,91,93), who have worked out a method of determining , 'in the technical grade of material, and have studied the kinetics of crystal growth from the melt of binary mixtures. A comparison slide technique for comparing the optical properties of a known with an unknown substance is given by Jellev (74).…”