in water crystn. on evapn. of an Al(OH)3 (satd. in the heat) and filtrated soln. of NaHC2O4 on a water-bath or by covering with a layer of alcohol;; addn. of a small amount of NaHC2O4 to prevent inclusion of Al2O3 in the crystals; recrystn. from aq. alcohol; impurities of Na-oxalate;;
参考文献
Journal of the Chemical Society, , vol. 123, p. 2739 - 2739
in water a mixture of NaHC2O4 and oxalic acid with the 3 - 4 fold amount of H2O is refluxed for 60 h; product pptd. on cooling;; the crystals are heated in their mother liquor with little OsO4 until the smell of OsO4 disappears; pure crystals are pptd. when soln. is cooled down; a second fraction is isolated from mother liquor after pptng. H2C2O4 with CaCl2;;
