Study on Flotation Separation and Determination of Mercury (II) by Sodium Bromide-Ammonium Thiocyanate-Octadecyl Trimethyl Ammonium Bromide System

Abstract:

The flotation separation and determination behaviours of mercury (Ⅱ) by sodium bromide -ammonium thiocyanide-octadecyl trimethyl ammonium bromide system were studied. The effects of different parameters,such as the dosages of NH₄SCN and octadecyl trimethyl ammonium bromide (OTMAB),various salts and acidity etc. on the flotation yield of Hg²⁺ have been investigated to select the experimental conditions.The results showed that in the presence of 1.0g NaBr and when the dosage of 0.1 mol/L NH₄SCN was 0.50 mL and 0.01 mol/L OTMAB solution was 1.00 mL respectively, the formed water-insoluble ternary association complex of (OTMAB)₂[Hg(SCN)₄] floated above water phase and liquid-solid phases were formed with clear interface. In this condition, Cd²⁺,Mn²⁺,Ni²⁺,Co²⁺,Fe²⁺ and Pb²⁺ could not be floated and Hg²⁺ could be floated quantitatively at pH2.0.Therefore, the quantitative separation of Hg²⁺ from the above metal ions could be achieved. A new method of determination of trace mercury by flotation separation was established.The proposed method has been successfully applied to the determination of Hg²⁺ in the sample of synthetic water and the flotation yield was 94.2%~97.9%.

• Periodical: Advanced Materials Research (Volumes 554-556)
• Pages: 1957-1961
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.554-556.1957
• Online since: July 2012
• Authors: Chang Qing Tu*, Xin Rong Wen
• Keywords: Ammonium Thiocyanate, Flotation Separation, Mercury(II), Octadecyl Trimethyl Ammonium Bromide

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