Objectives and content
Whatever the 21st century requires from industry, mandates to reduce waste are confronting us
today. For the countries of the E.U. the new PARCOM limits require especially for the metal
finishing industry, an optimized wastewater management. The lower concentration limit for
nickel (< 0,5 mg/l) may require a change in wastewater treatment technology.
"Zero discharge" is predicted as a future technology, that means no material ever leaves the
industrial process except as a product or a byproduct.
This project is aimed at the development of an integrated process for the recycling of nickel
salts from industrial electroplating nickelbaths and effluents.
The programme will make a comparative study between scaled up demonstrators of two
developed engineering concepts which are based on Supported Liquid Membranes (SLM)
using chemical driving forces for transfer, and Modified Electro-Dialysis (MED) using
electrochemical driving forces for transfer.
The results will be compared to conventional recycling and treatment systems. The concepts that we wish to exploit are:
- Nickel-ion extraction, presents an interesting challenge for the design and synthesis of selective and strong Ni-ligands.
- Anion extraction. Three types of reagents will be studied: - quaternary ammonium ions,
- macrocyclic metal complexes and
- redox switchable anion extractants.
- Ion-pairing extractants for nickel salt recovery.
- Electro-assisted liquid membrane extraction. The concept of a solid ion exchanger or a liquid membrane supported in a porous matrix as an ion selective membrane in an electrochemical cell will be engineered.
The extraction of nickel ions and anions present in industrial nickel plating baths, such as S04-, cr. (SO3NH2)-, BO3-, is of economical and ecological importance.
A pilot-scale modified electrodialysis cell and a modular SLM unit for nickel salts recycling will be tested with industrial nickel electrolytes and effluents.
The advantage of the proposed research is that the recycled nickel salts can be reused in nickel plating processes, thus saving costs and decreasing downstream processing and environmental problems. The new technology allows for residual nickel concentrations in effluents markedly below the PARCOM legislation.
Funding SchemeCSC - Cost-sharing contracts