Rapid Preparation of Ultrafine BaSO 3 by SO 2 Storage Material

In this work, a green and efficient process was developed for the preparation of ultrafine BaSO 3 with layered nanostructure surface via the reaction of BaCl 2 with a SO 2 storage material (SO 2 SM) at room temperature. The absorption of SO 2 with equimolar ethylenediamine (EDA) and ethylene glycol (EG) afforded SO 2 SM, which not only offered alkyl sulfite but also released EDA and EG that served as efficient surfactants to promote the formation of BaSO 3 with spherical morphology and porous structure in the process of synthesis of ultrafine BaSO 3 . The factors affecting the morphology and size of BaSO 3 particle were assessed by investigating the effects of SO 2 SM concentration, BaCl 2 concentration, stirring time and speed. It was found that a higher SO 2 SM concentration led to a higher degree of supersaturation, and the particle size of BaSO 3 could be reduced by increasing SO 2 SM concentration. Moreover, under the identified optimal reaction conditions, ultrafine BaSO 3 was obtained with an average diameter of 450 nm. In addition, a plausible formation process of BaSO 3 was proposed to explain the observed reaction results. Overall, the developed process in this work provides an efficient method for the capture, utilization, and conversion of SO 2 into a valuable chemical.