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How to Get Boron

Boron is too reactive to ever be found in nature and it is difficult to isolate. Almost all of the boron in the world comes from Turkey and the United States, with the commercially important sources being rasorite and tincal (borax ore). The following steps will illustrate the methods used to extract boron from these ores.

Instructions

- 1
  Refine borax (Na2B4O7 x 10H20) from its ore using mechanical means. React borax with sulfuric acid (H2SO4) to yield boric acid (B(OH)3). Heat the boric acid to obtain boric oxide using the following equation: 2(B(OH)3) + heat -> B2O3 + 3H2O. Reduce the boric oxide with magnesium as follows: B2O3 + 3Mg -> 2B + 3MgO.
- 2
  Utilize this method for demonstration purposes only. Although this is an easy reaction to initiate and was the first method used to isolate boron (along with a similar method using aluminum), the boron produced in this manner will be contaminated with significant amounts of magnesium diboride (MgB2), which is highly volatile.
- 3
  Produce boron commercially by reacting the boric oxide produced in step with hydrofluoric acid to yield boron trifluoride (BF3): B2O3 + 6HF -> 2BF3 + 3H2O. Boron trifluoride is then used to produce diborane (B2H6) with this reaction: 2BF3 + 6NaH -> B2H6 + 6NaF. Diborane can then be easily decomposed at high temperature into highly pure boron.
- 4
  Use the Czochralski process to further purify the boron for use in the semiconductor industry. The boron is melted in a crucible and a seed crystal of pure boron is mounted on a rod and dipped into the molten boron. The crystal is then withdrawn under precise conditions to extract a large, single crystal of pure boron.

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