Acid-Base Titrations in Nonaqueous Solvents

Abstract

The interest in nonaqueous chemistry is increasing as evidenced by the number of basic and analytical studies reported. During the past two years there has been a considerable advance in the understanding of acids, bases, and solvents. There has been some correlation of this information toward a scientific selection of a solvent and titrant for a specific analytical use.An increase in scope of acid-base titration in nonaqueous systems and some improvement in methodology have occurred, but the largest increase has been in specific applications.

Nonaqueous Titration of High Molecular Weight Nitrogen Compounds.

“…Cellulose powder (Brinkmann Instruments, Inc.) was a satisfactory adsorbent for thin layer separation of orthophosphate and pyrophosphate using the solvent system suggested by Kolloff (5). Silica gel G and aluminum…”

“…Short chain quaternary ammonium halides such as tetra-re-butylammonium bromide have been successfully determined in acetic anhydride using perchloric acid in acetic acid as titrant (7) but no procedure is reported for directly titrating the high molecular weight ammonium halides and methyl sulfate salts now of general commercial interest. Several procedures are reported in which the high molecular weight ammonium compounds are converted to acetates and titrated in propionic acid with perchloric acid (5) or in glacial acetic acid with perchloric acid (6), but these do not permit differentiation between salts with various anions.…”

Effect of dielectric constant of medium on protonation equilibria of ethylenediamine

“…EG is more acidic (less basic) than water (Feakins and Franks, 1967) due to electron withdrawing effect of CH 2 group. It offers several advantages as solvent in titration of weak bases (Johnson et al, 1961;Riddick, 1952). EG plays an important role in protein conformation studies (Sage and Singer, 1962;Inoue and Timasheff, 1968) because it is a weaker protein denaturant compared to urea or other organic solvents such as ethanol, dioxane etc.…”

Titrations in Nonaqueous Solvents

“…The review presented here covers papers which have been published in the interval between the last review by Riddick (98) and late September of 1961. Some papers published in this interval have been excluded when it was felt that they did not add appreciably to the present body of knowledge in this area.…”