Selective Recovery of Precious Metals by Selective Adsorption on Dimethylamine-Modified Persimmon Peel
For the purpose of developing a environmentally benign and cost effective process for the selective recovery of gold from a mixture of many kinds of metals, in a previous work, we found that persimmon peel gel is efficient for recovering Au(Ⅲ) as elemental gold. Since our present work is focused on the development of selective recovery of not only gold but also other precious metals like palladium and platinum, functional group of dimethylamine was chemically modified to obtain modified persimmon peel gel (DMA-PP). The adsorption behavior of the DMA-PP gel for various metal ions at varying hydrochloric acid concentrations has been studied. It was found that the DMA-PP exhibits high affinity not only for Au(Ⅲ) but also for Pt(Ⅳ) and Pd(Ⅱ) and no affinity for base metals such as Cu(Ⅱ), Fe(Ⅲ), Ni(Ⅱ), and Zn(Ⅱ). The apparent activation energy (is) evaluated suggests that adsorption of Au(Ⅲ) on the DMA-PP gel is a chemical phenomenon. Another important result is that the size of the gel is important on kinetics of gold adsorption and reduction. The application of this gel avoids the use of any additional reducing agents for the recovery of Au(Ⅲ) in elemental form.
Modified persimmon peel Adsorption Precious metals
Ying Xiong Chaitanya Raj Adhikari Hidetaka Kawakita Keisuke Ohto Hiroyuki Harada Katsutoshi Inoue
Department of Applied Chemistry, Saga University, Saga, Japan College of Chemistry, Liaoning Univers Department of Applied Chemistry, Saga University, Saga, Japan
国际会议
北京
英文
53-58
2010-05-17（万方平台首次上网日期，不代表论文的发表时间）