Effect of Citric Acid on Adsorption and Separation of Copper and Cadmium Using Chitosan

• Main Authors: Wen-Wei Hu, 胡文瑋
• Other Authors: Jia-Ming Chern
• Format: Others
• Language: en_US
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/17636586813830005400

碩士 === 大同大學 === 化學工程學系(所) === 93 === The effects of complexes on the sorption and separation of copper and cadmium from citrate solutions using chitoson were investigated. The four parameters that might control the metal sorption capacity include the fraction of protonated amine groups (RNH3+), the fraction of anionic metal-citrate complexes (CuL-, CdL-), the fraction of anionic citrate complexes (HL2-, H2L-, and L3-), and the chelating of the free metal cations (Cu2+, Cd2+) with the amine groups (RNH2). Various metals to citrate ratios and pHs were used to determine the heavy metal sorption capacity on the chitosan. The maximum sorption capacity above 2.5 mmol-metal/g showed that chitoson was very effective to sorb the heavy metals. According to the experimental and simulation results, the best conditions to separate copper and cadmium were Cu/Cd/Citrate molar ratio of 1/1/1 and the pH between 3.5 and 4.