Sciencemadness Discussion Board

Recycling of urushibara nickel

goldberg - 18-7-2018 at 01:48

I came across some literature about urushibara nickel and it looks very interesting.
It loses it's activity with use. I'm thinking about recovery of nickel after using this catalyst.
First i would like to separate zinc and nickel, and then convert nickel to its chloride salt so will can use it again.

Zinc can be dissolved in NaOH to form zinacte that is water soluble and after filtration i will end up with metallic nickel.
Literature says that dissolving nickel in hydrochloric acid is not that easy as it seems at first glance. I'm curious if nickel will react with sodium persulfate in similar manner to copper(standard PCB etching agent).
If so i can get easily nickel sulfate, then add hydroxide solution to get nickel hydroxide and finally react it with diluted hydrochloric acid to get nickel chloride.
Does it make sense?

Electrolytical dissolution of nickel is not an option because i will have fine powder so i can not easily make elctrode of it, i would prefer to avoid melting it due to high melting point of nickel and required labor to get such temperature.

Has anybody experience with this topic?
Also is there something that i should know (that is not obvious and/or described in the literature) before experimenting with this catalyst?

Loptr - 18-7-2018 at 13:23

Check out the attachment.

There is more to Urushibara than just precipitated nickel.

Attachment: New Hydrogenating Catalysts Urushibara.pdf (4.7MB)
This file has been downloaded 626 times

Loptr - 19-7-2018 at 13:03

Excerpt from my previous attachment.
Quote:

As for the soluble nickel salt, the chloride, nitrate, sulfate, and acetate were successively employed, and nickel chloride was found to be the most appropriate for obtaining a catalyst of high activity. Nickel nitrate solution hardly reacts with zinc dust, and nickel sulfate solution yields a catalyst of rather low activity. Nickel acetate, on the contrary, readily yields precipitated nickel, which proves to give as good a catalyst as that obtainable from nickel chloride.

goldberg - 20-7-2018 at 01:12

Thanks for article. I'm aware that Urushibara nickel needs activation and specific conditions for it's peparation.
I'm curious what is the best way to recycle it after being used up.
Also is there something non obvious about this catalyst that i should know before?

Loptr - 20-7-2018 at 05:21

As for non-obvious, there is a lot of non-obvious info in the paper, such specific variations of the catalyst of specific activity, temperature, reducing agent used to precipitate the nickel, etc. There are quite a few Urushibara catalysts, such as U-Ni-A, U-Ni-B, U-Ni-AA, U-Ni-BA, U-Ni-CB, U-Ni-CA, U-Ni-B(s), U-Ni-A(s), U-Ni-NH3, U-Ni-A(HCl), and not to mention those made with Cobalt or Iron.

I would suggest reading the paper.

Melgar - 20-7-2018 at 05:44

I don't know why you'd go through the trouble recycling a base metal like nickel. It loses its educational value after like one time.

https://www.ebay.com/sch/i.html?_nkw=nickel%20chloride&s...

Loptr - 20-7-2018 at 09:11

Quote: Originally posted by Melgar  
I don't know why you'd go through the trouble recycling a base metal like nickel. It loses its educational value after like one time.

https://www.ebay.com/sch/i.html?_nkw=nickel%20chloride&s...


I am not sure what you mean by "losing its educational value"?

I am fairly certain they meant to recycle the catalyst by reactivating it. It has to be converted back to a salt and then reprecipitated for recycling.

You might even be able to just redigest it, maybe? It would be subject to the law of diminishing return, of course.

[Edited on 20-7-2018 by Loptr]