Facile synthesis of ultrafine and high purity spherical strontium carbonate via gas-liquid reaction

Abstract In this work, a simple gas-liquid precipitation reaction was developed to fabricate spherical strontium carbonate (SrCO 3 ) particles using strontium hydroxide (Sr(OH) 2 ), carbon dioxide (CO 2 ) and ethylene diaminetetraacetic acid strontium salt (EDTA-Sr) as raw materials. The effects of the concentration of EDTA-Sr and Sr(OH) 2 , airflow rate of CO 2 and reaction temperature on the morphology of SrCO 3 were investigated. The results showed that spherical SrCO 3 particles can be formed when the concentration of EDTA-Sr reached 0.02 M as well as that of Sr(OH) 2 was less than 0.1 M. The airflow rate of CO 2 gas had little effect on the spherical morphology, and SrCO 3 microsphere with good dispersion could be obtained when the reaction temperature reached 50 °C. Under the optimal conditions ([EDTA-Sr] = 0.02 M, [Sr(OH) 2 ] = 0.1 M, 50 °C, [CO 2 ] = 1 l min −1 ), high purity spherical SrCO 3 particles with diameter of 200–800 nm can be easily obtained. Finally, the growth mechanism of spherical SrCO 3 has been preliminarily presented, which indicated that EDTA-Sr is an excellent structure-directing agent for forming pherical SrCO 3 particles. Our work offers an effective method for large-scale production of high purity spherical SrCO 3 .