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Building platinum plating equipment for teaching

I am a teacher and I am interested in building a bench platinum plating equipment. what do I need to make it in the chemistry lab?. My students are from Health Science.

Thank you,

Clara Hernandez
Universidad de Carabobo - Maracay, Aragua, Venezuela
2006

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First of two simultaneous responses -- 2006

Hello Clara,
If I understand the question correctly you will need a bench-top plating unit for electroplating Platinum. There are certain things you will need that are difficult to make, such as power supplies (rectifiers), heaters, inert anodes and small tanks. The number of process tanks would depend on the substrate metal you will be working from. You could use grade 316 stainless steel for cleaning tanks, white polypro should be used for precious metal plating. I don't normally promote company names on this website however, Technic, Inc. has a chemical division in Cranston, R.I. and a Equipment division in Pawtucket, RI that can supply the platinum metal plating solution, and have a wonderful Mini Lab Plater that would suit all your equipment needs. Good luck!

Mark Baker
process engineer - Malone, New York

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Second of two simultaneous responses -- 2006

You need plating rectifier (or lab transformer) and next chemicals: sodium platinate....20 gm
sodium hydroxide....5-6 gm
sodium oxalate......5-6 gm
sodium sulphate......33,7 gm
water ................1 lit
65-85 C/ 3-15 A/sq.ft.

or You can use old phosphate bath:
disodium phosphate.....100 gm
diammonium phosphate...20 gm
ammonium chloride......25 gm
platinum chloride......7,5 gm
10 ml ammonia(add to prepared bath)
water...................1 lit
70-80 C,5A /sq.ft.

(according to Fischer,Weimer: Precious Metal Plating [on Amazon affil links],Teddington 1964.)

Goran Budija
- Cerovski vrh Croatia

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Having read the first two responses, I fear that we may be on the way to persuading someone that plating is simply a matter of following a recipe. It is not.
Clara
Apart from the cost, platinum is one of the more difficult metals to plate. Certainly, following text book formulations may give a deposit, but you are unlikely to be satisfied with the result. Secondly, my colleagues should have advised you that preparation of the substrate is essential otherwise even a good deposit will blister or fall off completely. This will not impress your students.
Successful platinum plating is done from a chemical complex (P salt) supplied by specialist supply houses. The supplier wants you to be successful and will willingly give detailed advice on both equipment and control of the bath. Why platinum, what is the substrate, what thickness are you aiming for, how will you control the bath chemistry and man more questions before you can hope for a good deposit?

Geoff Smith
Hampshire, England
2006