Self-regulating Chromium Plating Baths for Fluoride

Waste Minimization in Chromium Plating Industry Waste Minimization in Chromium Plating Industry

Membrane electrolysis (ME) is the only commercial technology using ion-exchange membranes for chromic acid recycling and recovery. On one hand, the technology has a number of promising advantages, but on the other hand, it has not yet gained common acceptance probably due to a lack of operation stability and efficiency. Published results of the research can be divided into three categories: lab...

Zinc recovery and waste sludge minimization from chromium passivation baths.

This work reports the feasibility of applying emulsion pertraction technology (EPT) aiming at zinc recovery and waste minimization in the zinc electroplating processes that include Cr (III) passivation. The assessment consists of firstly the lifetime extension of the passivation baths by selective removal of the tramp ions zinc and iron, and secondly, the recovery of zinc for further reuse. Spe...

Pollution Prevention Technology Profile Trivalent Chromium Replacements for Hexavalent Chromium Plating

Alternatives to hard chromium plating on piston rods

As a main part of hydraulic cylinder, the piston rod is used in tough surrounding and corrosive condition; consequently a high quality protecting layer is essential. Currently EHC, electroplating hard chromium (hard chrome) is a widespread method for piston rod due to powerful performance and low cost. Unfortunately the plating process contains hexavalent chromium (Cr) which is toxic and carcin...

Chromium chains as polydentate fluoride ligands for lanthanides.

Hexametallic chromium(III) chains can act as fluoride donor ligands to lanthanide ions giving {(Cr(6))Ln(x)}(n) complexes; preliminary spectroscopic studies are reported.