The diversities of hydrogen sorption properties of Mg2FeH6-based complexes with and without TiO2 were investigated. Mg2FeH6-based complexes with and without TiO2 were synthesized respectively by reactive mechanical al...The diversities of hydrogen sorption properties of Mg2FeH6-based complexes with and without TiO2 were investigated. Mg2FeH6-based complexes with and without TiO2 were synthesized respectively by reactive mechanical alloying,and hydrogen sorption properties of the complexes were examined by Sieverts-type apparatus. The results show that the sample without TiO2 releases 4.43 % (mass fraction) hydrogen in 1.5 ks at 653 K under 0.1 MPa H2 pressure and absorbs 90% of the total 4.43 % (mass fraction) hydrogen absorbed in 85 s at 623 K under 4.0 MPa H2 pressure. But for the sample with TiO2 addition under the same condition,it only needs 400 s to release all of the stored hydrogen and 60 s to absorb 90% of the total hydrogen absorbed. The activation energies for desorption process of the samples with and without TiO2 are determined to be 71.2 and 80.3 kJ/(mol.K),respectively. The improvement in hydrogen sorption rate and and reduction in activation energy can be attributed to the addition of TiO2.展开更多
The sorption behavior and mechanism of a Macroporous weak acid resin, （D155 resin,） for Gd（Ⅲ） were investigated. The statically saturated sorption capacity is 283 mg/g resin at 298 K in HAc-NaAc medium. The Gd（...The sorption behavior and mechanism of a Macroporous weak acid resin, （D155 resin,） for Gd（Ⅲ） were investigated. The statically saturated sorption capacity is 283 mg/g resin at 298 K in HAc-NaAc medium. The Gd（Ⅲ） adsorbed on macroporous weak acid resin, （D155 resin,） could be reductively eluted with the mixed solution of HCl and NaCl, and the elution percentage was as high as 100%. The resin could be regenerated and reused without remarkable decrease in sorption capacity. The apparent sorption rate constant was k298=1.98×10^5 s^-1. The apparent activation energy was Ea=2.78 kJ/mol. The sorption behavior of D155 resin for Gd（Ⅲ） obeyed the Langmuir isotherm. The thermodynamic sorption parameters were △H=33.0 kJ/mol,△S=192 J/mol/K, and △G298=-24.3 kJ/mol. The sorption mechanism of D155 resin for Gd（Ⅲ） was examined by using chemical method and IR spectrometry. The coordination compound was formed between oxygen atoms in the functional group of D155 resin and Gd （Ⅲ）.展开更多
基金Project (50574105) supported by the National Natural Science Foundation of ChinaProject (NCET-06-0683) supported by the Program for the New Century Excellent Talents in University+1 种基金Project (08-030239) supported by the Program for 121 Excellent Talents in Hunan ProvinceProject (07MX21) supported by Mittal Student Innovation Foundation of Central South University
文摘The diversities of hydrogen sorption properties of Mg2FeH6-based complexes with and without TiO2 were investigated. Mg2FeH6-based complexes with and without TiO2 were synthesized respectively by reactive mechanical alloying,and hydrogen sorption properties of the complexes were examined by Sieverts-type apparatus. The results show that the sample without TiO2 releases 4.43 % (mass fraction) hydrogen in 1.5 ks at 653 K under 0.1 MPa H2 pressure and absorbs 90% of the total 4.43 % (mass fraction) hydrogen absorbed in 85 s at 623 K under 4.0 MPa H2 pressure. But for the sample with TiO2 addition under the same condition,it only needs 400 s to release all of the stored hydrogen and 60 s to absorb 90% of the total hydrogen absorbed. The activation energies for desorption process of the samples with and without TiO2 are determined to be 71.2 and 80.3 kJ/(mol.K),respectively. The improvement in hydrogen sorption rate and and reduction in activation energy can be attributed to the addition of TiO2.
基金the Zhejiang Provincial Natural Science Foundation of China (Y404279)
文摘The sorption behavior and mechanism of a Macroporous weak acid resin, （D155 resin,） for Gd（Ⅲ） were investigated. The statically saturated sorption capacity is 283 mg/g resin at 298 K in HAc-NaAc medium. The Gd（Ⅲ） adsorbed on macroporous weak acid resin, （D155 resin,） could be reductively eluted with the mixed solution of HCl and NaCl, and the elution percentage was as high as 100%. The resin could be regenerated and reused without remarkable decrease in sorption capacity. The apparent sorption rate constant was k298=1.98×10^5 s^-1. The apparent activation energy was Ea=2.78 kJ/mol. The sorption behavior of D155 resin for Gd（Ⅲ） obeyed the Langmuir isotherm. The thermodynamic sorption parameters were △H=33.0 kJ/mol,△S=192 J/mol/K, and △G298=-24.3 kJ/mol. The sorption mechanism of D155 resin for Gd（Ⅲ） was examined by using chemical method and IR spectrometry. The coordination compound was formed between oxygen atoms in the functional group of D155 resin and Gd （Ⅲ）.
