Basic Research On Cleaner Production Of High Purity Strontium Carbonate

Strontium carbonate is the primary material for color kinescope glass shell, cathode ray tubes,electronic ceramics, magnetic materials, fuel, paint and other industrial products, and high puritystrontium carbonate is the primary material for color picture tube, electronic ceramics, electroniccomponents. Current problems facing the research on barium carbonate production is that seriousenvironmental pollution, unstable product quality and higher production costs.On the basis of the preparation and summary of research on high purity SrCO3and optimizing theexisting process of high-purity SrCO3, cleaner production processes have been proposed for producinghigh purity SrCO3. And the article mainly studies the effect of temperature, holding time and thecatalyst on thermal decomposition of industrial SrCO3; the effect of temperature, stirring time on theyield Sr(OH)2; the effect of temperature, mixing time, ratio of ingredients, Sr(OH)2solutionconcentration and feed rate on physical and chemical properties of high purity SrCO3.Throughout the process, firstly, the strontium oxide is obtained by a pyrolysis of SrCO3, then thestrontium oxide obtained hydrolysis in water, exothermic and generates Sr(OH)2. With differentimpurities (Ca, Ba, Mg) hydroxides solubility difference, removing the industrial SrCO3calcium,magnesium, barium impurities, the Sr(OH)2purify by crystallization and the mixed solution wasrecrystallized with a solution of NaHCO3reaction, the final preparation of high-purity SrCO3. Theentire process did not add any acid, alkali, other chemicals and there is no discharge ofpollutants,which achieves a high purity SrCO3cleaner production.By using X-ray diffraction, EDSspectrum analyzer, SEM scanning electron microscopy and laser particle size analyzer for producttesting, the results showe that:Under the vacuum experimental conditions at1100℃, the thermal decomposition temperature ofthe industrial SrCO3can be reduced by adding C as a catalyst. And the decomposition rate of SrCO3isincreased to over91%. Under the conditions of105℃stirred for1hour, SrO hydrolysis reaction ofSr(OH)2reaches a yield of92%, after recrystallized twice by X-ray diffraction analysis, the obtainedis purity of Sr(OH)2is higher; At a experimental conditions of reaction temperature of70℃, Sr(OH)2concentration of0.4mol/L, a feed rate of2ml/L, stirring speed was300rpm/min, the prepared productof SrCO3was narrow particle size distribution, morphology is spherical, and basically without anyimpurities crystalline purity SrCO3better product by the X-ray diffraction, EDS spectrum analyzer,SEM scanning electron microscopy and laser particle size analyzer.The result indicates that in this process without adding chemicals, few polluting emissions, lowerthe cost of production, high purity strontium carbonate of stable quality was obtained and this processis feasible.