期刊名称：Revista Internacional de Contaminación Ambiental
印刷版ISSN：0188-4999
出版年度：2017
卷号：33
期号：1
页码：165-176
DOI：10.20937/RICA.2017.33.01.15
语种：English
出版社：Centro de Ciencias de la Atmósfera
摘要：Two synthetic and three natural magnetite samples that were obtained from an iron ore deposit located in Central-Western Mexico, were used to investigate the magnetite surface reactivity of different particle sizes towards aqueous Pb(II) and Zn(II). From these, the synthetic samples < 50 nm [specific surface area (SSA)] = 39.3 m 2 /g), 5 µm (SSA = 7.3 m 2 /g), and natural samples 948-fine (SSA = 7.6 m 2 /g), 948 (SSA = 3.0 m 2 /g) and 996 (SSA = 1.4 m 2 /g), successfully removed Pb(II) from aqueous solutions at the investigated pH value of 5.8, but only the three first, finer magnetites removed significant aqueous Zn(II) at pH 7.0. The adsorption kinetics data were fitted using pseudo-second order and intraparticle models. The Pb(II) adsorption capacities were 140.1, 33.3, 65.4, 69.8 and 17.0 µmol/g, for samples < 50 nm, < 5 µm, 948-fine, 948 and 996, respectively, while for Zn(II) they were 159.2, 38.8 and 28.2 µmol/g, for the first three previous samples, respectively. These adsorption capacities suggest that magnetite may play an important role as adsorbents of cationic contaminants in the environment, or that it may be used as efficient remediating agent, but it’s limited to particle sizes with specific surface areas above 3 m 2 /g.
其他摘要：Two synthetic and three natural magnetite samples that were obtained from an iron ore deposit located in Central-Western Mexico, were used to investigate the magnetite surface reactivity of different particle sizes towards aqueous Pb(II) and Zn(II). From these, the synthetic samples < 50 nm [specific surface area (SSA)] = 39.3 m 2 /g), 5 µm (SSA = 7.3 m 2 /g), and natural samples 948-fine (SSA = 7.6 m 2 /g), 948 (SSA = 3.0 m 2 /g) and 996 (SSA = 1.4 m 2 /g), successfully removed Pb(II) from aqueous solutions at the investigated pH value of 5.8, but only the three first, finer magnetites removed significant aqueous Zn(II) at pH 7.0. The adsorption kinetics data were fitted using pseudo-second order and intraparticle models. The Pb(II) adsorption capacities were 140.1, 33.3, 65.4, 69.8 and 17.0 µmol/g, for samples < 50 nm, < 5 µm, 948-fine, 948 and 996, respectively, while for Zn(II) they were 159.2, 38.8 and 28.2 µmol/g, for the first three previous samples, respectively. These adsorption capacities suggest that magnetite may play an important role as adsorbents of cationic contaminants in the environment, or that it may be used as efficient remediating agent, but it’s limited to particle sizes with specific surface areas above 3 m 2 /g.
