Sodium Tungstate Purification
Sodium tungstate purification is mainly removing molybdenum, arsenic, antimony, phosphorus, silicon, tin, fluorine and other impurities in the sodium tungstate solution, since tungsten concentrates usually treated by acid or alkali, particularly in the decomposition process of multiple NaOH. A large number of impurities in the sodium tungstate solution will prevent in the subsequent process, result in a low yield of tungsten, and even affect the quality of subsequent product of ammonium paratungstate and smelting wastewater treatment. Processes about purifying sodium tungstate are plentiful, along with the constantly updating of theoretical knowledge, practical experience and equipment, the cleaning process is also becoming sophisticated, thus to get higher purity products.
澳门老永利总部Studies have pointed out sodium tungstate purification method that mainly reduces the content of fluorine, phosphorus, arsenic, silicon and other impurities. Steps are as following: under the condition of 50-100℃, adjusting pH value of the sodium tungstate solution to precipitate silica; and then add magnesium salt, and control temperature higher than 50℃ with constantly stirring; filtered to give purified sodium tungstate.
澳门老永利总部In addition, there is an invention which pointed out the method for removing molybdenum, arsenic, antimony, tin; vulcanize sodium tungstate, then add precipitating agent to form the organic compound precipitation; add adsorbate and separated by filtration, to achieve the purpose of effective sodium tungstate purification.