Preparation of Porous Anhydrous MgCl₂ Particles by Spray Drying Process

Abstract

Polyethylene (PE) is indispensable materials in daily lives. The catalyst is necessary to produce PE. Ziegler-Natta catalysts were mostly used to produce PE which consisted of MgCl₂/TiCl₄ system. Polyethylene particle was reported to replicate the shape of the catalyst particles or catalyst support particles. Therefore, the MgCl₂ supports need to satisfy various requirements regarding particle morphology such as shape, particle size with uniform size distribution as well as the porosity. In this research, the preparation of MgCl₂ particles from irregular shape of anhydrous MgCl₂ by spray drying method was studied. However, because of the hygroscopic properties of anhydrous MgCl₂, all steps of experiment in this work were operated under dry N₂ atmosphere. The effect of type of alcohol, ethanol, n-propanol and n-butanol as solvent which was used to dissolve MgCl₂ before feeding through the spray drying on the particle properties were investigated. The amount of residual alcohol (alcoholic hydroxyl group content), morphology, specific surface area, porosity and crystallinity were determined by GC method, scanning electron microscope (SEM), N₂ sorption analyzer and X-ray diffraction (XRD), respectively. The results revealed that spray drying process can produce the porous anhydrous MgCl₂ particles which have rough surface, higher porosity and lower crystallinity than original anhydrous MgCl₂.