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General Forums => Generic Discussion => Topic started by: kavin011 on September 18, 2018, 07:26:00 AM

Title: Galvanized Iron (Zinc Coating Measurement)
Post by: kavin011 on September 18, 2018, 07:26:00 AM

Dear All,

     We are using Galvanized Iron wire as a raw material in our plant.As per BS EN standard we can measure the Zinc coating percentage of that wire. The procedure as follows(gravimetric method):

Reagents:
The stripping solution shall be hydrochloric acid with a concentration of 1.13 g/mi to 1.19 g/ml by density to which an appropriate inhibitor is added.Dissolve 3.2 g of antimony (III)Chloride or 2 g of antimony (III)oxide in 500 ml concentrated hydrochloric acid (1.19 g/ml).Dilute this solution with distilled water to 1 litre.Hexamethylenetetramine,formaldehyde or any other suitable inhibitor may be used.
Note: It is recommended that preference be given to inhibitors which do not contain antimony.


1) actually Zn coating  is dissolved in Hcl acid (37 %) ,but why these many compounds we need to use like SbCl3 /Sb2O3/C6H12N4/HCHO ?

2) My another doubt is after removing the Zn coating from iron , that iron also will dissolved into Hcl? thats why they using these many compounds? please clarify because Fe also easily dissolved into Hcl. If yes means kindly let me the occuring chemical reactions from that procedure.


 

Title: Re: Galvanized Iron (Zinc Coating Measurement)
Post by: Borek on September 18, 2018, 08:08:24 AM

Please don't cross post.

Locked.