Preparation of spherical magnesium oxide and study of thermal conductivity and adsorption properties

Spherical magnesium oxide was prepared by aerosol-assisted method using magnesium chloride as the magnesium source and urea as the precipitant. The precursors and magnesium oxide samples prepared at different reaction temperatures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (IR) and nitrogen adsorption-desorption. The experimental results showed that the specific surface area of the prepared spherical magnesium oxide was 36 m2/g, the average pore size was 34 nm, and the total pore volume was 0.26 cm3/g. The adsorption of Congo red was in accordance with the pseudo-secondary kinetics, and the adsorption equilibrium was reached within 5 min. The adsorption isotherm was in accordance with the Langmuir model, and the saturation adsorption capacity was 764.91 mg/g.

The invention provides a spherical magnesium oxide, said spherical magnesium oxide magnesium oxide purity content ≥ 85%, average particle

size 2150μm, sphericity ≥ 0.86, water content ≤ 8%wt, density 3.03.8g/cm; also provides a spherical magnesium oxide preparation method, including the provision of 89%99% purity, particle size 590μm, water content ≤ 3%wt magnesium oxide powder; will magnesium oxide The powder is melted by flame melting method to form a spherical droplet-like melt, and the combustion gas is selected from oxygen and natural gas to form a high temperature flame; cooling and shaping to form spherical magnesium oxide; and grading the spherical magnesium oxide. The beneficial effect of the invention is: the spherical magnesium oxide has a specific composition and average particle size, good sphericity, good fluidity, excellent thermal conductivity and other characteristics, the use of the electronic thermal conductivity material products with excellent thermal performance, long service life, high-cost performance, high thermal conductivity, single crystal thermal conductivity than magnesium oxide.