Comparison of sorption properties towards toxic metal ions of organomineral composites based on vermiculite with in situ immobilized and adsorbed poly [8-oxyquinoline methacrylate]

The purpose of the work is synthesis of new organomineral composites by in situ immobilization and adsorption of poly[8-methacroyloxy-quinoline] on the surface of vermiculite and study of sorption properties of cations Cu(II), Pb(II) and Fe(III). In situ immobilization of poly [8-oxyquinolinemethacrylate] on the surface of vermiculite was carried out by initiated radical polymerization of 8 oxyquinoline methacrylate using 2,2′-azobisisobutyronitrile (AIBN) as a dinitrile initiator in the presence of vermiculite. To obtain the composite by adsorption of poly[8-oxyquinolinemethacrylate] on the surface of vermiculite, the polymer was synthesized in advance, then dissolved in tetrahydrofuran and adsorbed on vermiculite. The fact of immobilization of poly[8-oxyquinolinemethacrylate] on the surface of vermiculite was confirmed by comparative analysis of the IR spectra of the source mineral and relative composites. The regularities of thermal decomposition of immobilized polymer were studied by thermogravimetric analysis combined with mass spectrometry. Using the results of low-temperature adsorption-desorption of nitrogen and scanning electron microscopy, changes in the morphology of the vermiculite surface after immobilization of poly[8-oxyquinolinemethacrylate] by the selected methods are shown. The sorption characteristics of the synthesized composites with respect to Cu(II), Pb(II) and Fe(III) ions were examined in static mode. The polymer with oxyquinoline groups immobilized on the surface of vermiculite showed sorption activity against those metal ions with which 8-oxyquinoline forms stable complexes, the sorption capacity relative to cations Cu(II) is doubled after in situ immobilization of poly [8-oxyquinoline methacrylate] on the surface of vermiculite and increases almost 3 times after adsorption of this polymer. For Pb(ІІ) ions this effect is lower: after in situ immobilization of [8-methacroyloxy-quinoline] sorption capacity increases by one-third and as the result, the increasing of adsorption of this polymer is insignificant and is within the experimental accuracy.