refining of rhodium from plating solution

bhupesh17 · Aug 21, 2011

hi,
i m bhupesh mulik frm mumbai,india
i hve a contaminated rhodium plating solution,i want to refine it to remove pure rhodium and again i want use it by making a bath of plating solution.
Is there any simple process to refining rhodium and making a plating solution?

samuel-a · Aug 21, 2011

contaminated with what?

bhupesh17 · Aug 22, 2011

hi i m using umicore rhodium j2 solution for plating , when i dip my jewellery for plating after degrassing ,that degrassing chemical -teepol30 change the colour of plating solution after 2-3 days,which effects on my plating colour of rhodium.so i use another fresh bath.but my impured bath has still some rh containing.i want to reuse again for plating.so i want any refining process and bath making process for this.i think it is contaminated with sodium,sulphtes,hydroxides,surfactants and dirt of polish wheels.

goldsilverpro · Aug 22, 2011

bhupesh17 said:
hi i m using umicore rhodium j2 solution for plating , when i dip my jewellery for plating after degrassing ,that degrassing chemical -teepol30 change the colour of plating solution after 2-3 days,which effects on my plating colour of rhodium.so i use another fresh bath.but my impured bath has still some rh containing.i want to reuse again for plating.so i want any refining process and bath making process for this.i think it is contaminated with sodium,sulphtes,hydroxides,surfactants and dirt of polish wheels.

This same question has been asked several times in the past and I really have no answer for it. You have both organic and inorganic contamination. The organics could possibly be removed by carbon filters but the carbon would most likely absorb some of the rhodium. The separation of Rh from the inorganic contamination (or, visa versa) would be much more complex. You could precipitate the Rh as metal with Mg powder, but that could even put you in a worse position. I guess the best advice would be to use better plating room practices and make every attempt to not to drag the other solutions into your Rh bath to start with. Also, try to do the plating in more of a clean-room setup and do the polishing in a separate room. To eliminate contamination 100% is impossible and all you could do is slow it down.

nickvc · Aug 22, 2011

You could try using an ultrasonic unit after polishing and then use an electro stripper after that before plating your items. Another thought may be to filter your rhodium solution and see if it removes some of the muck but do it cold, putting a cover over your solution when not in use may help keep some of the junk out to.