Processes for forming titanium catechol complexes

Abstract

Titanium complexes containing at least one catecholate ligand can be desirable active materials for flow batteries and other electrochemical energy storage systems. Such complexes can be formed through reacting a catechol compound with a titanium reagent in an organic solvent, removing a byproduct species, and then obtaining an aqueous phase containing a salt form of the titanium catechol complex, particularly an alkali metal salt form. More specifically, the methods can include: forming a catechol solution containing a catechol compound and an organic solvent, contacting a titanium reagent with the catechol solution to form a reaction mixture, reacting the titanium reagent with the catechol compound to form an intermediate titanium catechol complex and a byproduct species, separating the byproduct species, and combining an alkaline aqueous solution containing a base with the intermediate titanium catechol complex to produce a salt form titanium catechol complex at least partially dissolved in an aqueous phase.

Dependencies are inferred from the claim text.