Premium
Separation of tungstates from aqueous mixtures containing impurities (arsenate, phosphate and silicate anions) using ion flotation
Author(s) -
Zouboulis Anastasios I.,
Zhao YouCai,
Matis Kostas A.
Publication year - 1996
Publication title -
journal of chemical technology and biotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.64
H-Index - 117
eISSN - 1097-4660
pISSN - 0268-2575
DOI - 10.1002/(sici)1097-4660(199610)67:2<195::aid-jctb552>3.0.co;2-9
Subject(s) - arsenate , tungstate , aqueous solution , chemistry , inorganic chemistry , scheelite , leaching (pedology) , phosphate , impurity , magnesium , silicate , hydrometallurgy , reagent , tungsten , chloride , arsenic , organic chemistry , sulfuric acid , environmental science , soil science , soil water
Ion flotation, using dodecylamine as surfactant and magnesium ions as depressant agents, was found to be an effective method for the selective separation and recovery of tungstate from arsenate anions in dilute aqueous solutions. Arsenates represent the main impurity in tungsten‐containing waste waters or leaching solutions of hydrometallurgical origin; magnesium chloride is a relatively common precipitant, used in tungsten hydrometallurgy. The main parameters affecting this process were investigated, namely concentrations of reagents (Mg 2+ ions, dodecylamine, arsenate and tungstate), solution pH, co‐existence and effective separation from other impurities, such as phosphate and/or silicate anions, and the effectiveness of the separation process in solutions of high ionic strength (using NaCl and Na 2 SO 4 salts). It was found that at pH range between 2 and 5, tungstate anions can be quantitatively recovered from aqueous mixtures containing arsenates, phosphates and silicates, while the co‐removal of the impurities was below 20%.