Preparation of hydrated antimony pentoxide microspheres (diameter <20 μm) by water extraction variant of sol-gel process and its application to sorption of sodium

Hydrated antimony pentoxide (HAP) microspheres (diameter <20μm) were obtained in the following steps: (1) hydrolysis of SbCl 5 with water, (2) peptization of the resulting precipitate to the sols, (3) formation of sol emulsion in 2-ethylhexanol-1(EH), (4) gelation of emulsion drops by extraction of water with partially dehydrated EH. The obtained gels were then leached with water, concentrated NH 3 aq. or 3M HNO 3 , washed from NH 4 + , NO 3 ions and dried in ambient conditions. The XRD patterns have shown that all the samples have similar crystalline structure of Sb 2 O 5 . X H 2 O. However thermal analysis has shown that the prepared sorbents have initially the composition Sb 2 O 5 . 4 H 2 O. Retention of Na on all non calcined samples from 6M HCI solution has been studied under static and dynamic conditions. All samples showed good activity and stability, high sedimentation rate and low flow resistance.