Аннотация:New magnetic nanocomposite sorbents were obtained by doping natural bentonite with
nanosized CoFe2O4 spinel (10 and 20 wt.%). Nanocrystals of cobalt ferrite were synthesized by
a citrate burning method. The structure and physical-chemical properties of the composites were
characterized by XRD, XRF, TEM, BET, FTIR and Faraday balance magnetometry. During the
formation of nanocomposites, 10–30 nm particles of cobalt ferrite occupied mainly the interparticle
space of Fe-aluminosilicate that significantly changed the particle morphology and composite porosity,
but at the same time retained the structure of the 2:1 smectite layer. A combination of two functional
properties of composites, adsorption and magnetism has been found. The adsorption capacity of
magnetic nanosorbents exceeded this parameter for bentonite and spinel. Despite the decrease in the
adsorption volume, pore size and specific surface area of the composite material relative to bentonite,
the sorption activity of the composite increases by 12%, which indicated the influence of the magnetic
component on the sorption process. FTIR data confirmed the mechanism of formaldehyde sorption
by the composite sorbent. The production of a magnetic nanosorbent opens up new possibilities for
controlling the sorption processes and makes it possible to selectively separate the sorbent from the
adsorption medium by the action of a magnetic field.