45 results about "Thenardite" patented technology

The invention discloses a method for preparing lithium salt ore from plateau sulfate type salt lake brine. The method comprises the following steps of: evaporating sulfate type salt lake brine to be in the sodium chloride saturated state, freezing in winter to separate out mirabilite, and carrying out solid-liquid separation when the content of the sulfate ion in the brine is controlled to be 1g / L to 7g / L; evaporating the brine from which the mirabilite is separated out, so as to separate sodium chloride; evaporating the brine from which the sodium chloride is separated out, so as to separate out sylvine, carnallite and epsomite, carrying out solid-liquid separation when the lithium ion concentration in the brine is controlled to be greater than or equal to 6g / L, wherein the brine subjected to solid-liquid separation is the brine with high magnesium chloride content; mixing the brine with high magnesium chloride content with the mirabilite to react so as to separate out sodium salt and magnesium salt, and carrying out solid-liquid separation when the magnesium-lithium ratio in the solution is controlled to be less than or equal to 8:1, so as to obtain boron-lithium-rich brine; and reacting the boron-lithium-rich brine with water to separate out boron rock, carrying out solid-liquid separation so as to obtain lithium-rich brine; and introducing the lithium-rich brine into a lithium salt pool, and evaporating so as to separate out the lithium salt ore.

The invention relates to the field of a chemical industry and particularly relates to a method for preparing anhydrous sodium sulfate from chromium-containing mirabilite as a by-product in the production process of sodium dichromate. The method comprises dissolving a certain concentration of chrome-containing mirabilite in chromium-containing waste water, adding quantitative sodium thiosulfate into the waste water to promote reduction of hexavalent chromium into trivalent chromium under 0.1-1 Mpa at 80-190 DEG C, wherein the trivalent chromium in a form of chromium trioxide hydrate is precipitated, adding a small amount of sulfuric acid to neutralize, filtering to acquire the chromium trioxide hydrate, removing impurities, carrying out decoloration, evaporating to precipitate anhydrous sodium sulfate crystals, and carrying out continuous centrifugal separation and drying. The method is simple and easy, utilizes cheap raw materials, has low energy consumption and a high automation degree and is suitable for large-scale production. The quality of the industrial anhydrous sodium sulfate product obtained by the method meets the requirements of class I products in the GB / T 6009-2014 industrial anhydrous sodium sulfate standard.