Use of ethylenediamine disuccinic acid in metal surface treatment. (November 2013)

• Record Type: Journal Article
• Authors: Gough, T.; Giles, M. R.; Dixon, N. J.
• Is Part Of: Transactions of the Institute of Metal Finishing. Volume 91:Number 6(2013:Nov.)
• Page Start: 286
• Page End: 289
• Publication Date: 2013-11
• Subjects: Iron, -- Aluminium, -- EDDS, -- Rust removal, -- Corrosion, -- Cleaning; Metals -- Finishing -- Periodicals; Metals -- Surfaces -- Periodicals; Metallurgy -- Periodicals; 671.705
• DOI: 10.1179/0020296713Z.000000000147
• Languages: English
• ISSNs: 0020-2967

Abstract

Abstract : Hydrogen embrittlement is a continuing problem in the cleaning of metal surfaces. Furthermore, current processes often use strong acids and can have a poor environmental profile. Work is reported to show that ethylenediamine disuccinic acid (EDDS) offers an alternative process medium for a range of metals. The cleaning of the metal surface is environmentally friendly under mild conditions and does not result in hydrogen embrittlement. Rust removal from an iron surface can be achieved at neutral pH using EDDS at a low concentration. EDDS was found to be effective in hard water whereas the effectiveness of other chelants may be reduced by ions causing hardness. The results are consistent with the stability constants for metal ions which indicate that EDDS is selective for iron. Initial studies on aluminium have demonstrated that EDDS can remove metal deposits from an aluminium surface. Operation in neutral conditions means hydrogen is not generated, removing any risk of embrittlement. EDDS also offers some corrosion inhibition of aluminium and does not produce discoloration of the surface.