Recovery of Sb3+ Ions by Biogenic Silicon-Containing Materials

Functional silicon-containing materials—silicon–carbon product, high-purity amorphous silicon dioxide, sodium aluminosilicate, and iron-containing magnetoactive composite material with specific surface area from 56.7 to 470 m 2 /g—have been obtained from agricultural wastes (rice husk and straw). Chemical and phase composition of obtained samples have been determined, particle morphology has been established by scanning electron microscopy, specific surface area has been measured, IR spectra have been recorded. The possibility to use the obtained materials for the removal of antimony ions from aqueous solutions has been studied. It has been found that sodium aluminosilicate and iron-containing composite materials based on biogenic silica show high capacity toward antimony ions: 596 and 386 mg/g, respectively. Used approach, in the first place, allows one to reclaim safely rice straw and husk and to reduce atmospheric emission of microdisperse amorphous silica SiO 2 resulting from their open combustion and causing respiratory diseases. In the second place, the study enables purification of natural and technogeneous wastewaters contaminated by antimony(III), which form on the sites of antimony rock deposits on their decay and mining.