Two chemically modified starch derivatives, crosslinked amino starch (CAS) and dithiocarbamates modified starch (DTCS), were prepared and used for the removal of Cu(II) from aqueous solutions. CAS was found to be effective for the adsorption of Cu(II), which tended to form a stable amine complex. Adsorption of Cu(II) onto DTCS was higher than that onto CAS. Experiments showed that the adsorption processes of Cu(II) on both CAS and DTCS were endothermic, and followed Freundlich isothermal adsorption. For both adsorbents, dynamic modeling of their adsorption showed that the first-order reversible kinetic model described the adsorption process. The adsorption rate constants of CAS and DTCS were 1.578 and 10.32 h Ϫ1 , respectively. From the results of the thermodynamic analysis, free energy ⌬G, enthalpy ⌬H, and entropy ⌬S of the adsorption process were calculated.

This work investigated sorption properties of diethylenetriamine derivative of chitosan (CTSN) for removal of acid dyes (Acid Green 25 (AG25), Acid Red 18 (AR18) and Acid Orange 10 (AO10)) from aqueous solutions. Sorption kinetics was firstly evaluated. It was found that pseudo-second-order model fits well with these dyes adsorbed on CTSN. Compared with normal chitosan, CTSN has higher capacity for AR18 and AO10, but a lower value for AG25. Mechanisms and interactions of dyes with CTSN were also discussed by study the effect of pH, influence of hydrogen-bonding and comparing the sorption capacities.

An aminated D-glucose [N,N'-di-b-D-glucopyranosyl ethylenediamine] was prepared and thoroughly characterized by FT-IR, ESI-MS, NMR spectra and elemental analysis. Compared with D-glucose, the FT-IR spectrum of the aminated glucose showed a moderate peak at 1629~1608 cm-1which was attributed to dNH vibration, suggesting glucose reacted to ethylenediamine (en). The ESI-MS spectrum exhibited a strong peak atm/z383.2, which was assigned to the species [C14H27O10N2]-. The1H-NMR spectrum of the aminated D-glucose demonstrated the signal of the C1proton and the amino proton at 4.82~4.79ppm, illustrating the amino of ethylenediamine was substituted for the hydroxy group of C1. As for UV spectra, the aminated glucose hadn’t absorbance in the ultraviolet region while its complex with Cu2+had obvious absorption peak at about 236nm. The complex ratio of the aminated glucose to Cu2+was close to 1:1 and the stability constant of its Cu2+complex was 6.8*107in 0.01mol×L-1borax buffer solution.