News | April 18, 2018

Technology Meets Sustainability – ZI-NI Bath Of An Infinite Operationality

Zinc-Nickel plating established itself in the last years to be the gold standard for corrosion protection of steel parts in various industries. Alkaline Zinc-Nickel plating in particular is unmatched in its performance and sustainability due to low metal concentrations in the bath, superior metal- and alloy-distribution and, as a consequence, very reliable corrosion protection. This is how Zinc-Nickel plating by itself helps to make corrosion protection more eco-friendly by eliminating toxic materials like Chromic Acid or Cadmium otherwise needed to achieve the same performance.

COVENTYA made another contribution to improve the sustainability of the Zinc-Nickel technology by developing a unique and patent protected porous membrane technology known as „3S“. The separation of the anodes from the plating bath prevents the formation of undesired oxidation products which lower the efficiency of the plating process and can also be toxic (like e.g. Cyanide).

The first generation of membrane anodes for Zinc-Nickel plating was developed over 20 years ago and was used as ion-exchange membranes. This technology showed the potential of the concept of anode separation, but had also some drawbacks in the continuous operation, like the unwanted transfer of water or hydroxide. The new porous membrane anodes prevent this unwanted transfer. In contrast, they show a positive side effect by removing carbonate and sulfate from the plating electrolyte which naturally occurs in operation and by replenishment, thus giving the plating bath a practically infinite lifetime at the highest performance level. The resulting consistent high current efficiency also reduces significantly the energy demand for plating and cooling. Over 50% energy can be saved on a comparative basis. Another important ecological contribution is the dramatically reduced waste as no bleed-and-feed or freeze-out etc. is required to keep up productivity

COVENTYA 3S membrane anodes are running day to day in close to one million liters of Zinc-Nickel electrolyte thus providing eco-friendly and highly efficient corrosion protection worldwide.

Source: COVENTYA