# Last edited on 2017-02-06 02:04:04 by stolfilocal

Cleanup of silicon carbide abrasive powder (1000 mesh)
bought from F.F. Comercial

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2016-09-11 [1]

Added 100 ml of water to 42 g of raw SiC powder and thoroughly stirred.
The mixture had 114 ml.  This implies a density of 42 g / 14 ml = 3.00 g/ml.
Tables say that the density of SiC is 3.21 g/ml.  Discepancy may be
due to trapped air or impurities.

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2016-09-11 [2]

Rough filter to remove water, then added white vinegar (diluted acetic
acid, ~5%).  No visible reaction.  Filtered (clear liquid)

The powder was then treated with strong solutio of NaHCO3 (saturated
at 20 C) and heated to boiling.  

Filtrated. The liquid had a slight rust-like tone.  Added liquid to 
the vinegar wash.  Instead of the expected CO2 evolution, a white
fluffy ppt formed.  Possibly the NaHCO3 was tuned into sodium
silicate, and the precipitate was silica? 

Weight of SiC after washing and drying was still ~42 g