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Title: Recovery process for electroless plating baths

Abstract

A process is described for removing, from spent electroless metal plating bath solutions, accumulated byproducts and counter-ions that have deleterious effects on plating. The solution, or a portion thereof, is passed through a selected cation exchange resin bed in hydrogen form, the resin selected from strong acid cation exchangers and combinations of intermediate acid cation exchangers with strong acid cation exchangers. Sodium and nickel ions are sorbed in the selected cation exchanger, with little removal of other constituents. The remaining solution is subjected to sulfate removal through precipitation of calcium sulfate hemihydrate using, sequentially, CaO and then CaCO[sub 3]. Phosphite removal from the solution is accomplished by the addition of MgO to form magnesium phosphite trihydrate. The washed precipitates of these steps can be safely discarded in nontoxic land fills, or used in various chemical industries. Finally, any remaining solution can be concentrated, adjusted for pH, and be ready for reuse. The plating metal can be removed from the exchanger with sulfuric acid or with the filtrate from the magnesium phosphite precipitation forming a sulfate of the plating metal for reuse. The process is illustrated as applied to processing electroless nickel plating baths. 18 figs.

Inventors:
;
Issue Date:
OSTI Identifier:
7073213
Patent Number(s):
5112392 A
Application Number:
PPN: US 7-719201
Assignee:
Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States) PTO; EDB-94-081325
DOE Contract Number:  
AC05-84OR21400
Resource Type:
Patent
Resource Relation:
Patent File Date: 21 Jun 1991
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; NICKEL; PLATING; PROCESS SOLUTIONS; DEMETALLIZATION; CALCIUM CARBONATES; CALCIUM OXIDES; ION EXCHANGE; ION EXCHANGE MATERIALS; MAGNESIUM OXIDES; METAL INDUSTRY; RECYCLING; ALKALINE EARTH METAL COMPOUNDS; CALCIUM COMPOUNDS; CARBON COMPOUNDS; CARBONATES; CHALCOGENIDES; DEPOSITION; DISPERSIONS; ELEMENTS; INDUSTRY; MAGNESIUM COMPOUNDS; MATERIALS; METALS; MIXTURES; OXIDES; OXYGEN COMPOUNDS; SEPARATION PROCESSES; SOLUTIONS; SURFACE COATING; TRANSITION ELEMENTS; 320305* - Energy Conservation, Consumption, & Utilization- Industrial & Agricultural Processes- Industrial Waste Management

Citation Formats

Anderson, R.W., and Neff, W.A. Recovery process for electroless plating baths. United States: N. p., 1992. Web.
Anderson, R.W., & Neff, W.A. Recovery process for electroless plating baths. United States.
Anderson, R.W., and Neff, W.A. Tue . "Recovery process for electroless plating baths". United States.
@article{osti_7073213,
title = {Recovery process for electroless plating baths},
author = {Anderson, R.W. and Neff, W.A.},
abstractNote = {A process is described for removing, from spent electroless metal plating bath solutions, accumulated byproducts and counter-ions that have deleterious effects on plating. The solution, or a portion thereof, is passed through a selected cation exchange resin bed in hydrogen form, the resin selected from strong acid cation exchangers and combinations of intermediate acid cation exchangers with strong acid cation exchangers. Sodium and nickel ions are sorbed in the selected cation exchanger, with little removal of other constituents. The remaining solution is subjected to sulfate removal through precipitation of calcium sulfate hemihydrate using, sequentially, CaO and then CaCO[sub 3]. Phosphite removal from the solution is accomplished by the addition of MgO to form magnesium phosphite trihydrate. The washed precipitates of these steps can be safely discarded in nontoxic land fills, or used in various chemical industries. Finally, any remaining solution can be concentrated, adjusted for pH, and be ready for reuse. The plating metal can be removed from the exchanger with sulfuric acid or with the filtrate from the magnesium phosphite precipitation forming a sulfate of the plating metal for reuse. The process is illustrated as applied to processing electroless nickel plating baths. 18 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1992},
month = {5}
}