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There are many methods available to obtain powdered metals and alloys. Wikipedia show some of them. Another form is grinding with posterior removal of wheel particles. All these methods produce metal powder with the help of specific machinery. I am asking for an alternative wet chemical method (water solution) or electrochemical method (water or ionic liquid electrolyte) to obtain metal powder (specifically iron, nickel and silicon, in pure or controlled alloy form).

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closed as unclear what you're asking by Klaus-Dieter Warzecha, Geoff Hutchison, Martin - マーチン, Philipp, LDC3 May 20 '15 at 1:36

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ I want to obtain powder of those metals (pure, not alloyed) without an atomizing machine. $\endgroup$ – user3368561 May 11 '15 at 14:09
  • $\begingroup$ I need power of separate element or mixed in known proportion. Grinding will introduce impurities. ¿Will they be easy to remove? I need a small amount, big enough to be overpriced if I buy it from a laboratory supplier and small enough so that I can not import from a wholesaler. $\endgroup$ – user3368561 May 14 '15 at 16:40
  • $\begingroup$ Even after reading all the comments, I still don't understand what you are asking. Could you revise the question? Otherwise it might get closed as too vague. $\endgroup$ – Curt F. May 15 '15 at 12:32
  • $\begingroup$ Thanks for updating! I'm still a bit confused by "obtain metal powder (specifically iron, nickel and silicon, in pure or controlled alloy form)". Does that mean you are asking for (a) three separate wet electrochemical methods, one for Fe, one for Ni, and one for Si; OR (b) a single method to generate a Fe-Ni-Si alloy; OR (c) both? $\endgroup$ – Curt F. May 15 '15 at 14:03
  • $\begingroup$ @CurtF. (a) or (b) or both. As fewer restrictions are imposed, more likely to get a answer. $\endgroup$ – user3368561 May 15 '15 at 16:00
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Both metal powders can be preapred electrochemically.

Iron dust is prepared using solution containing $\ce{FeCl3}$ with addition of $\ce{AlCl3}$ to make the solution more conductive. The process occurs at elevated temperature 60°C. Unfortunately exact process parameters are hard to find. But following graph could help.

enter image description here

Nickel could be prepared electrochemically too and can be prepared by dissolving of Ni-Al alloy in hydroxide -Raney_nickel. The description of patent is here.

This is link to a study book PRÁŠKOVÁ METALURGIE, K. Skotnicová, M. Kursa , unfortunately only in czech.

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  • $\begingroup$ Nickel powder can be made by electrolysis as well. Raney nickel is a speciality for use as a hydrogenating catalyst, and is very pyrophoric! $\endgroup$ – Georg May 15 '15 at 14:54
  • $\begingroup$ Did you even read my answer? I am saying on 2 positions that the electrolysis is possible. Altough the powder is pyrophoric, it is a way how to prepare the nickel dust. What was actually the question. $\endgroup$ – Jaroslav Kotowski May 15 '15 at 16:13
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I am asking for an alternative wet chemical method (water solution) or electrochemical method (water or ionic liquid electrolyte)

Water will only be a efficient electrolyte to generate metals that are more weakly reducing than hydrogen gas. Otherwise, attempts to produce the metal will just result in mostly water hydrolysis. The chemwiki page at UC Davis has a good overview of this particular topic. The standard reduction potential for iron is too low (too reducing; too negative) to be made efficiently via an aqueous electrochemical process. Update: I softened the wording of this paragraph based on advice from Jaroslav Kotowski who noted that the original wording I used was wrong. Iron dust can apparently be made via electrolysis, but efficiency is very low.

Nickel and silicon are less powerful reducing agents than iron, but are still slightly more powerful than water under standard conditions. Some combination of pH and concentration adjustment could make it theoretically possible to generate these metals in a wet (aqueous) electrochemical process, but it would not be very efficient. I dug up a 1908 paper that reports that nickel films (not powders) can be electrodeposited from a (presumably aqueous) solution of nickel ammonium sulfate.

Non-aqueous electrolytes such as ionic liquids do not necessarily have this problem. You should read a review article on metal deposition from non-aqueous media such as this one.

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  • $\begingroup$ Thanks Jaroslav -- I'll edit the answer to reflect this. $\endgroup$ – Curt F. May 15 '15 at 19:35

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