Abstract

A review of the periodic table demonstrates that while many elements may be capable of tanning, only a few useful options exist. One of these is titanium; the usual compounds for tanning agents are based on the stable (IV) oxidation state or, more empirically, the TiO2ion. However, there is also Ti(III) which can exist as the hexaaquotitanium (III) ion, [Ti(H2O)613,a metastable oxidation state with the potential for tanning. A literature search has revealed a dearth of information about the complex chemistry of titanium (III). However, there are magnetic resonance spectroscopy techniques available to investigate complex formation. The reaction between Ti(III) and vegetable tannin has been investigated and a method to determine the titanium content of leathers developed.