Morphological Investigation of Sodium Oxalate Crystals Grown in Aqueous Sodium Hydroxide Solution
Sodium oxalate crystals grown in aqueous sodium hydroxide solutions with different concentrations were characterized by optical and atomic force microscopy to examine their morphologies. Experimental results indicated that a high concentration of sodium hydroxide had a dramatic effect on reducing the size of sodium oxalate crystals. A nitrogen gas adsorption technique was employed to quantify the change of specific surface area of sodium oxalate. A two dimensional image analysis technique was also employed to estimate surface area and the crystal size distribution of sodium oxalate.
KeywordsSodium oxalate Crystallization Bayer process Image analysis
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