Abstract:
A method for removing iron ions from galvanizing flux solution includes adding zinc chloride and ammonium chloride to a solvent in a preparing tank to prepare a first galvanizing flux solution which is transferred to a treatment tank, immersing an iron/steel piece in the first galvanizing flux solution to dissolve part of the surface to form iron ions, adding oxygen-rich gas to the first galvanizing flux solution to oxidize the iron ions to form a second galvanizing flux solution containing iron oxide precipitation, filtering the second galvanizing flux solution by a multilayer filter to form a third galvanizing flux solution without iron oxide or with low content of iron oxide, transferring the third galvanizing flux solution back to the treatment tank, and repeating the above steps by immersing another iron/steel piece in the first galvanizing flux solution so as to continuously remove iron ions generated.
Abstract:
In a lead-free hot-dip galvanizing method and its processed product, a pure zinc tablet with a 99.995% purity is used and a conventional zinc solution containing lead is changed to a novel hot-dip galvanizing zinc solution for the hot dip galvanizing process. The hot-dip galvanizing zinc solution has a composition of 98% to 99% of zinc, 0.2% to 1.0% of aluminum and less than 1% of a trace element by weight, so that this hot dip galvanizing process with a lead and cadmium free galvanizing condition is achieved.