A novel Ni（Ⅱ） ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid（AMPS） as a func...A novel Ni（Ⅱ） ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid（AMPS） as a functional monomer for the selective separation of Ni（Ⅱ） from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni（Ⅱ） at the optimal p H of 7.0 was 66.22 mg·g^（-1）. The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni（Ⅱ）/Co（Ⅱ）, Ni（Ⅱ）/Cu（Ⅱ）, Ni（Ⅱ）/Zn（Ⅱ） and Ni（Ⅱ）/Pb（Ⅱ）, respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni（Ⅱ） was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni（Ⅱ） in real water samples.展开更多
Based on the principle and calibration of vapor pressure os-mometer and itsapplication in the thermodynamics of the aqueous solutions, the results on aqueous solutions ofmonomer glycol, PEG_(200), PEG_(400), PEG_(1500...Based on the principle and calibration of vapor pressure os-mometer and itsapplication in the thermodynamics of the aqueous solutions, the results on aqueous solutions ofmonomer glycol, PEG_(200), PEG_(400), PEG_(1500) and PEG_(2000) over the different concentrationrange at various temperatures were reported. Using a linear least-square fitting routing, theosmotic coefficients were fitted by a simple polynomial equation. It was found that the relationshipbetween the molar osmotic coefficients (Φ) and the molar concentration (c) of the solutions are ina quite good agreement with the fitted polynomial equation at various temperatures over thedifferent concentration range. The experimental results also show that over the studiedconcentration range and at various temperatures, the concentration dependence of the molar osmoticcoefficients of the aqueous solution systems with the solutes of PEG_(200), PEG_(400), PEG_(1500)and PEG_(2000) are totally presented in a rising trend, and their temperature dependence of theosmotic coefficients of the aqueous solution systems of the molar concentration exhibits their ownregularities, respectively. The aqueous glycol solution system exhibits the properties of the dilutesolution.展开更多
文摘A novel Ni（Ⅱ） ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid（AMPS） as a functional monomer for the selective separation of Ni（Ⅱ） from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni（Ⅱ） at the optimal p H of 7.0 was 66.22 mg·g^（-1）. The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni（Ⅱ）/Co（Ⅱ）, Ni（Ⅱ）/Cu（Ⅱ）, Ni（Ⅱ）/Zn（Ⅱ） and Ni（Ⅱ）/Pb（Ⅱ）, respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni（Ⅱ） was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni（Ⅱ） in real water samples.
文摘Based on the principle and calibration of vapor pressure os-mometer and itsapplication in the thermodynamics of the aqueous solutions, the results on aqueous solutions ofmonomer glycol, PEG_(200), PEG_(400), PEG_(1500) and PEG_(2000) over the different concentrationrange at various temperatures were reported. Using a linear least-square fitting routing, theosmotic coefficients were fitted by a simple polynomial equation. It was found that the relationshipbetween the molar osmotic coefficients (Φ) and the molar concentration (c) of the solutions are ina quite good agreement with the fitted polynomial equation at various temperatures over thedifferent concentration range. The experimental results also show that over the studiedconcentration range and at various temperatures, the concentration dependence of the molar osmoticcoefficients of the aqueous solution systems with the solutes of PEG_(200), PEG_(400), PEG_(1500)and PEG_(2000) are totally presented in a rising trend, and their temperature dependence of theosmotic coefficients of the aqueous solution systems of the molar concentration exhibits their ownregularities, respectively. The aqueous glycol solution system exhibits the properties of the dilutesolution.
