The sorption of Cu(II) from an aqueous solution using ZSM-5 zeolite was investigated by batch technique under ambient conditions. Sorption was investigated as a function of pH, ionic strength, foreign ions, humic substances, and temperature. The results indicate that the sorption of Cu(II) on ZSM-5 zeolite is strongly dependent on pH. Sorption is dependent on ionic strength at low pH, but independent of ionic strength at high pH values. The presence of humic/fluvic acid (HA/FA) enhances the sorption of Cu(II) on ZSM-5 zeolite at low pH values, and reduces Cu(II) sorption at high pH values. Sorption isotherms were well simulated by the Langmuir model. Thermodynamic parameters (i.e., deltaH0, deltaS0 and deltaG0) for the sorption of Cu(II) were determined from temperature-dependent sorption isotherms at 293.15, 313.15, and 333.15 K, respectively. Results indicate that the sorption process of Cu(II) on ZSM-5 zeolite is spontaneous and endothermic. 相似文献
Phthalates (PAEs) in drinking water sources such as the Yangtze River in developing countries had aroused widespread concern. Here, the water, suspended particulate matter (SPM), and sediment samples were collected from 15 sites in wet and dry seasons in Zhenjiang, for the determination of six PAEs (DMP, DEP, DIBP, DBP, DEHP, and DOP) using the solid-phase extraction (SPE) or ultrasonic extraction coupled with gas chromatography-mass spectrometry (GC-MS). The total concentrations of six PAEs (Σ6PAEs) spanned a range of 2.65–39.31 μg L?1 in water, 1.97–34.10 μg g?1 in SPM, and 0.93–34.70 μg g?1 in sediment. The partition coefficients (Kd1) of PAEs in water and SPM phase ranged from 0.004 to 3.36 L g?1 in the wet season and from 0.12 to 2.84 L g?1 in the dry season. Kd2 of PAEs in water and sediment phase was 0.001–9.75 L g?1 in the wet season and 0.006–8.05 L g?1 in the dry season. The dominant PAEs were DIBP, DBP, and DEHP in water and SPM, DIBP, DEHP, and DOP in sediment. The concentration of DBP in water exceeded the China Surface Water Standard. The discharge of domestic sewage and industrial wastewater might be the main potential sources of PAEs. The risk quotient (RQ) method used for the risk assessment revealed that DBP (0.01 < RQ < 1) posed a medium risk, while DIBP and DEHP (RQ > 1) posed a high environmental risk in water, DIBP (RQ > 1) also showed a high risk in sediment.