Synthesis and surface properties of submicron barium sulfate particles

• Published in: Applied surface science Vol. 258; no. 1; pp. 24 - 29
• Main Authors: Zhang, Ming, Zhang, Bao, Li, Xinhai, Yin, Zhoulan, Guo, Xueyi
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.10.2011; Elsevier
• Subjects: Barite; Barium sulfate; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Conditional formation constants; Constants; Cross-disciplinary physics: materials science; rheology; Dispersions; EDTA; Exact sciences and technology; Isoelectric point; Mathematical models; Morphology; Physics; Precipitation method; Scanning electron microscopy; Conditional formation constants; Precipitation method; Isoelectric point; Barium sulfate; Barium; Precipitation; Surface properties
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2011.07.137

► A fabrication process of submicron BaSO 4 was presented and their surface chemical composition and bonding were studied. ► The effects of the preparation parameters were investigated. ► pH value has significant effect on the particle size. ► An electrical double layer exists around BaSO 4 particle. ► The adsorption of the functional groups of EDTA can shift the isoelectric point of BaSO 4 particle to the lower pH level. Barium sulfate particles were synthesized in the presence of EDTA at room temperature. X-ray diffractometry (XRD), Fourier transform infrared resonance (FTIR) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of BaSO 4 particles. The effect of the preparation parameters on the particle size distribution and morphology was investigated. The conditional formation constants of Ba-EDTA at different pH values were calculated. The results show that the size and morphology of BaSO 4 particles can be effectively controlled by adding EDTA in the precipitation process. Among all the operation conditions, the pH value has significant effect on the particle size. The obtained barium sulfate particles are spherical and well dispersed at pH = 9–10. Zeta potentials of BaSO 4 were measured at different pH. The isoelectric point (IEP) of barium sulfate colloid appears at pH 6.92. The model of the solid–solution interface at a particle of BaSO 4 was presented. The FTIR result indicates that the surface of the prepared BaSO 4 absorbs the functional groups of EDTA, which lower the IEP of the barium sulfate particles.