中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 20 No. 6 June 2010 |
（1. Faculty of Life Science and Technology, Central South University of Forestry and Technology,
Changsha 410004, China;
2. College of Environmental Science and Engineering, Hunan University, Changsha 410082, China;
3. Key Laboratory of Environmental Biology and Pollution Control of Ministry of Education, Hunan University,
Changsha 410082, China;
4. State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, China）
Abstract:An important filamentous industrial fungus, Rhizopus cohnii (R. cohnii), was used as an efficient biosorbent for removing cadmium from wastewater. The sorption conditions, such as pH, the dose of biomass and the initial concentration of cadmium were examined. Two kinds of adsorption models were applied to simulate the biosorption data. The uptake of cadmium was higher in weak acid condition than in strong acid condition. Nearly no sorption of cadmium occurred when the pH value was lower than 2.0. Biosorption isothermal data could be well simulated by both Langmuir and Freundlich models. Langmuir simulation of the biosorption showed that the maximum uptake of cadmium was 40.5 mg/g (0.36 mmol/g) in the optimal conditions, which was higher than many other adsorbents, including biosorbents and activated carbon. In addition, the reusability results showed that after five times of sorption and desorption process, the sorption capacity of R. cohnii could still maintain nearly 80%, confirming its practical application in cadmium treatment. Fourier transform infrared spectrum revealed that carboxyl, amino and hydroxyl groups on biosorbent R. cohnii surface were responsible for the biosorption of cadmium.
Key words: biosorption; Rhizopus cohnii; biosorbent; cadmium
