Ni^(2+)印迹磁性交联壳聚糖微球的选择性吸附性能

以Ni^(2+)为模板离子、壳聚糖为主要原料、Fe_(3)O_(4)为磁核、环氧氯丙烷为交联剂,制备了Ni^(2+)印迹磁性交联壳聚糖微球。表征结果显示,微球呈现立体结构,表面有较多褶皱,结晶度降低,有利于对Ni^(2+)的吸附。二元金属离子体系的选择性吸附结果表明,等浓度和不同浓度的Ni^(2+)-Cu^(2+)、Ni^(2+)-Zn^(2+)、Ni^(2+)-Cr^(2+)混合溶液中,微球对Ni^(2+)均有较好的选择性吸附性能,随着Ni^(2+)浓度的增加选择吸附系数增大。Ni^(2+)-Zn^(2+)-Cu^(2+)-Cr^(2+)四元金属离子体系的选择性吸附结果表明,微球对Ni^(2+)的平衡吸附量明显大于其他3种金属离子,平衡吸附量的大小顺序为Ni^(2+)>Cu^(2+)>Zn^(2+)>Cr^(2+),Ni^(2+)相对于Cu^(2+)、Zn^(2+)和Cr^(2+)的选择吸附系数分别为81.545、156.529和544.720。

Cr_2WO_6纳米晶的水热法制备及其对亚甲基蓝的选择性吸附性能

以Cr(NO3)3·6H2O、Na2WO4·2H2O为原料,去离子水为溶剂,采用水热法在不同pH条件下成功制备出颗粒状结构的Cr2WO6纳米晶。采用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)、能谱分析(EDS)和Lambda 950分光光度计分别对产物的物相、形貌和光学性能进行表征,讨论了不同pH对Cr2WO6纳米晶的结构的影响,并对合成粉体的选择性吸附性能进行了研究.结果表明:在水热条件下,前驱体的酸碱性对合成Cr2WO6纳米晶的结构有很明显的影响,只有在弱酸条件下才可以得到Cr2WO6纳米晶.此外,与传统固相法得到的产物相比,水热条件下制备的Cr2WO6纳米晶对亚甲基蓝具有明显优越的选择性吸附性能.

An Effective Method to Improve the Performance of Fixed Carrier Membrane via Incorporation of C02-selective Adsorptive Silica Nanopartlcles

Fixed carrier membrane exhibits attractive CO2 permeance and selectivity due to its transport mechanism of reaction selectivity （facilitated transport）. However, its performance needs improvement to meet cost targets for CO2 capture. This study attempts to develop membranes with multiple permselective mechanisms in order to enhance CO2 separation performance of fixed carder membrane. In this study, a novel membrane with multiplepermselective mechanisms of solubility selectivity and reaction selectivity was developed by incorporating CO2-selective adsorptive silica nanoparticles in situ into the tertiary amine containing polyamide membrane formed by interfacial polymerization （IP）. Various techniques were employed to characterize the polyamide and polyam-ide-silica composite membranes. The TGA result shows that nanocomposite membranes exhlbit superior-thermal stability than pure polyamide membranes. In addition, gas permeation experiments show that both nanocomposite membranes have larger CO2 permeance than pure polyamide membranes. The enhanced CO2/N2 separation performance for nanocomposite membranes is mainly due to the thin film thickness, and multiple permselective mechanisms of solubility selectivity and reaction selectivity.