Thioglycolic Acid (TGA) or its salts like Sodium Thioglycolate, CAS# 367-51-1, as 46% solution are used in various cleaners formulation. Also Thiolactic Acid, CAS# 79-42-5, and its salts which are classified non-toxic can be used.
On one side the reducing properties of the Thioglycolid Acid or the Thioglycolate and on the other hand the capability to form metal-thioglycolate complexes especially with iron are responsible for the excellent performance in cleaning of metal surfaces and other applications.
Thus metal oxides partially are reduced to the metals and in an aquous environment a metal complex like Iron Thioglycolate is formed.
A typical application based on these properties is auto rim cleaning or rust removing. The auto rim cleaner will reduce the rust particles in the break dust, loosen the dirt particles and the formation of the deep red Iron Thioglycolate complex indicates that the cleaning formulation has worked.
But also other metals or alloys can be cleaned. In stainless steel distillation plants for distilled water the ultra pure water corrodes the stainles stell. The brown stain can be removed by a derouging process with Sodium Thioglycolate containing formulations, see also Henkel Pickling and Electropolishing.
Another application is removing rust spots from mineral surfaces like granite or concrete, even marble as the Sodium Thioglycolate formulation can be adjusted rather pH-neutral and thus does not corrode the mineral surface. The rust is reduced to iron.
Derusting of tools made of iron containing alloys is a typical example. In general metals can be derustet.
Another application is removing rust spots from mineral surfaces like granite or concrete, even marble as the Cleaner can be formulated pH-neutral so that it will not corrode the surface of materials which are sensitive to acids.
For more Information:
Dr. Tom Beyersdorff
Technical Marketing Manager
Fon: +49 4176 9098-68