The octadecylamine-hectorite composite (ODA-hectotie) has been designed and synthesized. The composite is used for removal of methylene blue (MB) from aqueous solution. Research concerning the effects of pH, composite dose, initial dye concentration and temperature are presented and discussed. Experiment results showed that the equilibrium adsorption data fitted well with the Langmuir isotherm. Respectively, the experiment data was analyzed using intra-particle diffusion and film diffusion. The characteristic parameters for each model have been determined.

Magnetic core/alumina shell (MFeCA) structured nanospheres were obtained from a hematite core/alumina precursor shell (HFeCAP) nanosphere precursor. A uniform alumina layer was coated on the surface of α-Fe 2 O 3 by the self-assembly of a stearic acid/alumina isopropoxide complex. Hematite cores of the nanospheres were then reduced under H 2 /N 2 gas flow to produce the MFeCA nanospheres. Transmission electron microscopy images showed that the products possessed a distinct core-shell structure. N 2 sorption measurements showed that the uniform accessible pore size was 5.2 nm. The surface area was 140m 2 /g and pore volume were 0.22 cm 3 /g. Saturation magnetization values indicated the product had a high degree of magnetization (50.2 emu/g).

Abstract. The properties of hectorite was strongly affected by their microstructures and purity. Here Na x Li x Mg 3-x Si 4 O 10 (OH) 2 ·4H 2 O multilayer pancakelike structures were fabricated successfully by hydrothermal reaction of Na 2 SiO 3 ·9H 2 O, MgCl 2 ·6H 2 O and LiCl·H 2 O in autoclave at 473K. The synthesis process of hectorite were observed by XRD. The formation mechanism of Na x Li x Mg 3-x Si 4 O 10 (OH) 2 ·4H 2 O was discussed. The influence of temperature and proportion reactants to hectorite were proposed. The amorphous hectorite was formed firstly. Then the hectortie particles aggregated and oriented assembly with the help of reaction temperature. The effected of proportion of reactants such as molar fraction of LiCl and the Mg/Si molar ratio were discussed. The purity of hectorite changed regularly with different Mg/Si molar ratio.

Hectorite has been designed and synthesized by hydrothermal way, which is used for removal of methylene blue (MB) from aqueous solution. The experiment data was analyzed using pseudo-second-order kinetics, intra-particle diffusion and film diffusion. The characteristic parameters for each model have been determined. Thermodynamic parameters such as activation(E a), standard free energy(ΔG 0), the enthalpy(ΔH 0) and the entropy(ΔS 0) were also evaluated. The negative value of ΔG 0 (kJ/mol) and ΔH 0 (kJ/mol) indicates the spontaneous and exothermic nature of the reactions. The data of E a shows the physisorption process of MB on hectorite.

Magnetic core/alumina shell (MFeCA) structured nanospheres were obtained by a hematite core/alumina precursor shell (HFeCAP) nanosphere precursor. A uniform alumina layer was coated on the surface of α-Fe2O3 by the self-assembly of a stearic acid/alumina isopropoxide complex. Hematite cores of the nanospheres were then reduced under H 2 /N 2 gas flow to produce the MFeCA nanospheres. Transmission electron microscopy images showed that the products possessed a distinct core-shell structure. N 2 sorption measurements showed that the uniform accessible pore size was 4.0 nm. The surface area was 140m 2 /g and pore volume was 0.22 cm 3 /g. Saturation magnetization values indicated the product had a high degree of magnetization (50.2 emu/g).