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Title: Inhibition of nickel precipitation by organic ligands

Abstract

Wastewaters from electroplating are very complex due to the composition of the plating baths. A nickel plating bath typically consists of a nickel source (nickel chloride or nickel sulfate), complexing agents to solubilize nickel ions controlling their concentration in the solution, buffering agents to maintain pH, brighteners to improve brightness of the plated metal, stabilizers (inhibitors) to prevent undesired reactions, accelerators to enhance speed of reactions, wetting agents to reduce surface tension at the metal surface, and reducing agents (only for electroless nickel plating) to supply electrons for reduction of the nickel. Alkaline precipitation is the most common method of recovering nickel from wastewaters. However, organic constituents found in the wastewaters can mask or completely inhibit the precipitation of nickel. The objective of this study was to conduct an equilibrium study to explore the inhibition behavior of various organic ligands on nickel precipitation. This will lay the groundwork for development of technologies efficacious in the treatment of complexed nickel. The organic ligands used in this study are EDTA, triethanolamine (TEA), gluconate, and tartrate.

Authors:
; ;  [1]
  1. Univ. of Connecticut, Storrs, CT (United States)
Publication Date:
OSTI Identifier:
395297
Report Number(s):
CONF-9505206-
Journal ID: ISSN 0073-7682; TRN: IM9648%%420
Resource Type:
Book
Resource Relation:
Conference: 50. Purdue industrial waste conference, W. Lafayette, IN (United States), 8-10 May 1995; Other Information: PBD: 1996; Related Information: Is Part Of Proceedings of the 50. industrial waste conference; Wukasch, R.F. [ed.]; PB: 861 p.
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 54 ENVIRONMENTAL SCIENCES; WASTE WATER; DEMETALLIZATION; NICKEL; PRECIPITATION; ORGANIC COMPOUNDS; CATALYTIC EFFECTS; NICKEL HYDROXIDES; SOLUBILITY; EXPERIMENTAL DATA

Citation Formats

Hu, H.L., Nikolaidis, N.P., and Grasso, D.. Inhibition of nickel precipitation by organic ligands. United States: N. p., 1996. Web.
Hu, H.L., Nikolaidis, N.P., & Grasso, D.. Inhibition of nickel precipitation by organic ligands. United States.
Hu, H.L., Nikolaidis, N.P., and Grasso, D.. 1996. "Inhibition of nickel precipitation by organic ligands". United States. doi:.
@article{osti_395297,
title = {Inhibition of nickel precipitation by organic ligands},
author = {Hu, H.L. and Nikolaidis, N.P. and Grasso, D.},
abstractNote = {Wastewaters from electroplating are very complex due to the composition of the plating baths. A nickel plating bath typically consists of a nickel source (nickel chloride or nickel sulfate), complexing agents to solubilize nickel ions controlling their concentration in the solution, buffering agents to maintain pH, brighteners to improve brightness of the plated metal, stabilizers (inhibitors) to prevent undesired reactions, accelerators to enhance speed of reactions, wetting agents to reduce surface tension at the metal surface, and reducing agents (only for electroless nickel plating) to supply electrons for reduction of the nickel. Alkaline precipitation is the most common method of recovering nickel from wastewaters. However, organic constituents found in the wastewaters can mask or completely inhibit the precipitation of nickel. The objective of this study was to conduct an equilibrium study to explore the inhibition behavior of various organic ligands on nickel precipitation. This will lay the groundwork for development of technologies efficacious in the treatment of complexed nickel. The organic ligands used in this study are EDTA, triethanolamine (TEA), gluconate, and tartrate.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1996,
month =
}

Book:
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