Study on Chromium(VI) and Arsenic(V) adsorption onto basic oxygen furnace slag

• Main Authors: Hsien-TaKao, 高賢達
• Other Authors: Yen-Hua Chen
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/32122313001870869200

碩士 === 國立成功大學 === 地球科學系 === 102 === The objective of this study is to discuss the adsorption ability and mechanism of Cr6+ and As5+ onto basic oxygen furnace slags. The maximum Cr6+ and As5+ adsorption capacity of slag is 1.38 and 13.91 mg/g, respectively. Further, the Langmuir isotherm is more adequate in simulating the adsorption isotherm of Cr6+ and As5+. It also suggests that the experimental data are well fitted to the pseudo-second-order equation. The adsorption capacity of slags increases with the increasing temperature. This indicates the reaction is occurred through chemical adsorption. Basis on EDS analyses, the metal ions are adsorbed on the phases of calcite, larnite and srebrodolskite; the FTIR results also show the vibrational mode of calcite has a redshift after adsorption. It indicates the Cr6+ and As5+ ions are co-precipitated with calcium ions along with calcite precipitation to adsorbed onto calcite and larnite. Moreover, the metal ions can also formed complexes on srebrodolskite via the hydroxide layer of the mineral surface.