Synthesis and Characterization of Magnetic Nanoparticles for Enhanced Gas-Liquid Mass Transfer

Abstract

Magnetite particles were synthesized by the coprecipitation of iron (II) and iron (III) chlorides in the presence of a surfactant and ammine base. These particles had relatively low internal surface areas, but high external surface due to the small particle diameter. Silica coated magnetite particles were synthesized by the hydrolysis of tetraorthosilicate (TEOS) and the coprecipitation of iron chlorides in the presence of different surfactants and an ammine base. Commercial magnetite nanoparticles were also coated with silica using TEOS and a base in the presence or absence of a dispersant. All samples were characterized using XRD, SEM, TEM, and nitrogen adsorption to obtain diffraction patterns, particle morphology data, and BET surface areas. Adsorption isotherm studies were conducted for the adsorption of trichloroethylene from aqueous samples on to low surface area magnetite nanoparticles and high surface area silica coated magnetite nanoparticles. Studies were also conducted on the effect of nanoparticles on the effect of high and low surface area nanoparticles on gas-liquid mass transfer in aqueous systems. This paper will present data on the synthesis and characterization of these nanoparticles and their potential to enhance mass transfer in gas-liquid systems.