Laboratory Testing & General Mineral Processing Engineering

Laboratory Testing & General Mineral Processing Engineering 2017-04-04T06:57:51+00:00
  • To participate in the 911Metallurgist Forums, be sure to JOINLOGIN
  • Use Add New Topic to ask a New Question/Discussion about Mineral Processing or Laboratory Work.
  • OR Select a Topic that Interests you.
  • Use Add Reply = to Reply/Participate in a Topic/Discussion (most frequent).
    Using Add Reply allows you to Attach Images or PDF files and provide a more complete input.
  • Use Add Comment = to comment on someone else’s Reply in an already active Topic/Discussion.

separating mixed metal oxide fines (2 replies)

1 year ago
spanner 1 year ago

We are producing a mixed metal hydroxide cake principally containing magnesium, ferrous iron, aluminium, zinc, copper and manganese. There are also smaller volumes of chromium, barium, cadmium, nickel, Beryllium, cobalt, strontium. We need help to separate these metal hydroxides, preferably to high purity metals.

Can anyone assist us.
1 year ago
Wayne 1 year ago
1 like by David

Hi spanner,

What about dissolving in H2SO4 and doing selective pH and precipitate the hydroxides individually?

This may not work for all species as things like nickel and cobalt are very close in pH at precipitation although we have had some success with nickel cobalt separation using a solvent extraction post precipitation and re acidification.

I am thinking and although you can start to separate using pH not all will separate into the purities that I believe you would like. and unfortunately you will still run the gamut of a huge number of steps and techniques including sulfide precipitation, Pyro-metallurgy etc.

You can separate them but the question is at what cost?

Sorry I can't be of more help at this time.

Cheers, Wayne


12 months ago
jpearcy 12 months ago
1 like by David

This is a very complex problem, for which it is unlikely that an economical process could be proposed, because there are no noble metals that could justify the expense in a multistage metallurgical separation process. However, here are some ideas on a possible theoretical route to separating the metals.

1.- I would think that Aluminum powder could be added to the mixed metals oxides, so that at high temperature the aluminothermal reduction of all metal oxides, with the exeption of the Al2O3 and MgO would take place. Reduced metals and oxides would form two inmiscible liquid phases and a gas phase, so that Mg and Al oxides could be removed as slag, pure Zn would distill off as vapor and could be recovered by cooling and condensation, and the other metals would remain in the melt.

2.- The mixed molten metals could then be subject to chlorination, which would facilitate the fractional distillation of the various metal chlorides (chlorides boiling points are very different for different metals). These metal chlorides could be reduced to the respective metals by known processes. Need to check Ellingham diagram to decide which best applies for each one of these.

3.- The slag consisting of mixed Mg and Al oxides could be subject to reaction with HCl to selectively convert MgO into MgCl2, which is soluble, and could be separated from the Al2O3. Electrolysis of MgCl2(s) is a known commercial process. Note that HCl would be produced in case H2 was used for reduction for some of the metals in step (2) above.

Hope this helps, or at least serves to stimulate further thinking on this challenging problem.

Please join and login to participate and leave a comment.

BUY Laboratory & Small Plant Process Equipment

We have all the laboratory and plant equipment you need to test or build/operate your plant.

ENTER our Mining Equipment' Store

We Sell EQUIPMENT for all types of Mineral Treatment PROCESSES and Laboratory Testing needs

Have a Mineral Processing QUESTION?

Come in, ask your question

911Metallurgist Community Forums

Talk to other metallurgists and be helped.


We can IMPROVE ALL PLANTS / Mineral Processing Engineering & LABORATORY Ore Testing

911Metallurgy Engineering

Contact us for process engineering, metallurgical investigations, plant optimization, plant troubleshooting, needs. WE “FIX” METALLURGY.