Hydrotalcite-like compound (HTlc) with a Mg/AI molar ratio of 2 : 1 was synthesized by using a coprecipitation method and the sorption removal of Cu(Ⅱ) by the Mg-AI HTlc sample from CuSO4 solution was investigat...Hydrotalcite-like compound (HTlc) with a Mg/AI molar ratio of 2 : 1 was synthesized by using a coprecipitation method and the sorption removal of Cu(Ⅱ) by the Mg-AI HTlc sample from CuSO4 solution was investigated. It was found that the Mg-AI HTlc showed a good sorption ability for Cu(Ⅱ) from CuSO4 solution, indicating that the use of hydrotalcite-like compounds as promising inorganic sorbents for the removal of heavy metal ions from water is possible. The sorption kinetics and the sorption isotherm of Cu(Ⅱ) on the HTlc obeyed the pseudo-second order kinetic model and Langmuir equation, respectively. The percent removal of Cu(Ⅱ) by the HT1c was strongly dependent on the initial pH of bulk solution. It increased sharply with the increase of initial pH value in the range of 5-7, and was relatively small in the initial pH range of 4-5, while it reached about 100% after initial pH was higher than 7. The presence of AlCl3 might obviously lower the equilibrium sorption amount (qc) of Cu(Ⅱ) on the HTlc. However, the presences of NaCI and MgCl2 might increase the qe. The presences of ligands (citric acid and EDTA) in the studied concentration range might obviously decrease the qe of Cu(Ⅱ) on the HT1c. The removal mechanism of Cu(Ⅱ) cations by HTlc in the presence of SO4^2- anions may be attributed to the surface-induced precipitation of Cu(Ⅱ) hydroxides and the surface complex adsorption by the linking effect of SO4^2- between the HTlc and Cu(Ⅱ) cations, and the removal ability arising from the surface-induced precipitation is much higher than that from the linking effect of SO4^2-.展开更多
Desulfurization of gasoline distillation with adsorption was studied at ambient temperature and pressure by using CuNaY(NaY exchanged with copper nitrate aqueous solution) as the adsorbents.The gasoline distillation...Desulfurization of gasoline distillation with adsorption was studied at ambient temperature and pressure by using CuNaY(NaY exchanged with copper nitrate aqueous solution) as the adsorbents.The gasoline distillation was composed of thiophene-cyclohexane solution(115.0 μg/mL) with or without toluene.For the solution without toluene,no detectable sulfur was found in the effluent when the effluent volume was less than 40 mL,while the addition of toluene resulted in an evident drop of the adsorption performance for(CuNaY.) FTIR spectra indicate that the conversion of Cu2+ to Cu+ took place during the pretreatment of(CuNaY) adsorbent,and the interaction mode between the adsorbed thiophene molecules and Cu+ is π complexation.This adsorption mode is easily affected by aromatic compounds,resulting in the significant decrease of adsorption capacity in model gasoline containing toluene on CuNaY.展开更多
基金Project supported by the Natural Science Foundation of Shandong Province of China (Nos. Z2008B08 and ZR2009BZ001), Taishan Scholar Foundation of Shandong Province of China (No. ts20070713) and the Education Natural Science Foundation of Henan Province (No. 2010B150021 ),
文摘Hydrotalcite-like compound (HTlc) with a Mg/AI molar ratio of 2 : 1 was synthesized by using a coprecipitation method and the sorption removal of Cu(Ⅱ) by the Mg-AI HTlc sample from CuSO4 solution was investigated. It was found that the Mg-AI HTlc showed a good sorption ability for Cu(Ⅱ) from CuSO4 solution, indicating that the use of hydrotalcite-like compounds as promising inorganic sorbents for the removal of heavy metal ions from water is possible. The sorption kinetics and the sorption isotherm of Cu(Ⅱ) on the HTlc obeyed the pseudo-second order kinetic model and Langmuir equation, respectively. The percent removal of Cu(Ⅱ) by the HT1c was strongly dependent on the initial pH of bulk solution. It increased sharply with the increase of initial pH value in the range of 5-7, and was relatively small in the initial pH range of 4-5, while it reached about 100% after initial pH was higher than 7. The presence of AlCl3 might obviously lower the equilibrium sorption amount (qc) of Cu(Ⅱ) on the HTlc. However, the presences of NaCI and MgCl2 might increase the qe. The presences of ligands (citric acid and EDTA) in the studied concentration range might obviously decrease the qe of Cu(Ⅱ) on the HT1c. The removal mechanism of Cu(Ⅱ) cations by HTlc in the presence of SO4^2- anions may be attributed to the surface-induced precipitation of Cu(Ⅱ) hydroxides and the surface complex adsorption by the linking effect of SO4^2- between the HTlc and Cu(Ⅱ) cations, and the removal ability arising from the surface-induced precipitation is much higher than that from the linking effect of SO4^2-.
文摘Desulfurization of gasoline distillation with adsorption was studied at ambient temperature and pressure by using CuNaY(NaY exchanged with copper nitrate aqueous solution) as the adsorbents.The gasoline distillation was composed of thiophene-cyclohexane solution(115.0 μg/mL) with or without toluene.For the solution without toluene,no detectable sulfur was found in the effluent when the effluent volume was less than 40 mL,while the addition of toluene resulted in an evident drop of the adsorption performance for(CuNaY.) FTIR spectra indicate that the conversion of Cu2+ to Cu+ took place during the pretreatment of(CuNaY) adsorbent,and the interaction mode between the adsorbed thiophene molecules and Cu+ is π complexation.This adsorption mode is easily affected by aromatic compounds,resulting in the significant decrease of adsorption capacity in model gasoline containing toluene on CuNaY.