Separation of Iron Oxide in Coal Fly Ash by the Magnetic Field for the Removal of Aqueous Copper Ions

• Main Authors: Sui-Ming Ou, 歐書銘
• Other Authors: Chien-Jung Lin
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/83529800377364562459

碩士 === 嘉南藥理科技大學 === 環境工程與科學系暨研究所 === 94 === An effective solution to the problem is in demand. According to the finding in the study, the specific adsorption capacity（SAC）of copper ions using fly ashes with different mineral compositions as adsorbents varied violently. It was found that the SAC of fly ash in adsorbing copper ion was in the range of 0.12 and 1.87（mg Cu2+ / g fly ash）and correlated with the mineral composition of Fe2O3 and SiO2 in the coal fly ashes. The metal oxides in the fly ashes with different point of zero charge（PZC）carry positive or negative charge according to the solution pH. When the pH of the solution is higher than the PZC of the metal oxide, the charge on the surface of the oxide is negative. On the other hand, the charge on the surface of the oxide is negative, when the pH of the solution is higher than the PZC. In this search, the coal fly ash was gathered from power plant. Iron oxides in fly ash will be specified separated from other minerals by means of electric-magnetic separation system（EMSS）developed in this study. Substances from EMSS were collected as adsorbents and were applied to adsorb copper ions from aqueous solution in the adsorption experiment. Finally, the feasibility of iron oxides specified separated by EMSS will be discussed in detail. Research result shows that the Al2O3 and SiO2 content in separated products increased when PH was control at 4、7、10. The BET of products from EMSS, increased from 1.05(m2/g) to 2.65(m2/g). The specific adsorption capacity of copper ions was 2.11( mg-Cu2+ / g-fly ash ). In addition, the absolute recovery rate of fly ash increased with solution pH and intensity of magnetic field. CEC of the separated products remained unchanged. However, when fly ashes soaked in aqueous solution, CEC of fly ashes increased with solution pH.