【作者】 王慧琴；

【导师】 吴坤；

【作者基本信息】 河南农业大学 ， 微生物学， 2008， 硕士

【摘要】 从白腐菌真菌中筛到一株高吸附稀土的菌株,即黄孢原毛平革菌210。本文在全面评述生物吸附吸附重金属的理论和技术的基础上,对黄孢原毛平革菌吸附稀土离子的性能进行了研究。黄孢原毛平革菌对稀土的吸附试验结果表明,培养72h的菌对稀土具有较好的吸附能力。溶液pH、吸附时间、菌体投加量、稀土离子浓度对黄孢原毛平革菌210吸附稀土离子影响显著。吸附的最佳pH值为7;菌体的最佳投加量为3mg/50mL(干重);菌体对稀土浓度为40mg/L时吸附量最高;解吸试验和菌株的预处理试验结果表明,加入解吸剂柠檬酸和EDTA都能较好地解吸稀土离子。盐酸处理的菌体对稀土的吸附能力有所提高,其他处理后,菌体吸附能力下降;通过吸附前后电镜照片比较,发现吸附后菌体上出现了白色亮斑,表明吸附了稀土离子。做单一稀土选择性试验时,发现黄孢原毛平革菌210对稀土具有良好的选择性。用ICP-OES做混合稀土吸附试验时,发现菌体对Lu、Sm、Eu的吸附量很高,对其他稀土的吸附差别不是特别明显,黄孢原毛平革菌210可以对混合稀土离子起到富集、分离的作用。菌株对稀土离子的吸附分为两个过程是:首先是一个快速的吸附过程,吸附量有很大的提高,而在第二个阶段吸附量的增加速度很慢。研究发现菌体对稀土离子的吸附符合Langmuir吸附模型和Freundlich吸附模型,和Langmuir吸附模型符合程度更好。对黄孢原毛平革菌210吸附稀土离子进行动力学分析表明,吸附过程遵从准二级动力学模型。更多还原

【Abstract】 Phanerochaete chrysosporium210 which has high adsorption capacity of La3+ was screened from white rot fungi.At present, the action mechanism of biosorbent has not been studied indetail. Based on reviewing theories and techniques of heavy metal removal,the absorbing capability of Phanerochaete chrysosporium210 toREE is studied.The adsorption experiments of Phanerochaete chrysosporium210 (cultivation 72h) to REE are done. The results indicated that the pH, adsorptive time, biomass concentration and REE concentration were crucial factors for biosorption of REE The suitable pH was 7, The optimal adsorptive time is 2h, and biomass concentration 3mg/50ml(dry weight). When the concentration of REE is 40mg/L, adsorption capacity of REE is the largest.Desorption and pretreatment test of Phanerochaete chrysosporium210 indicate that it has a better desorption affect by joining the Citrate acid, and EDTA. Preatreatment by acid of Phanerochaete chrysosporium210 can increase the biosorption capacity a little. And the biosorption capacity on Phanerochaete chrysosporium210 by other pretreatments decreases.Comparing the TEM characterization of Phanerochaete chrysosporium210 before &after adsorbing La3+, lots of wite bright spots ware found in the cell wall of after adsorbing Phanerochaete chrysosporium210 ,So we guess that Phanerochaete chrysosporium210 adsorbed La3+.Tests were done with solution containing one REE at a time ,accumulation ability of Phanerochaete chrysosporium was quite diffenert .the selective biosorption with mixture REEs sulution showed Phanerochaete chrysosporium210 preferentially biosorpted Lu,Sm,Eu.the biosorption difference is not obvious for other REEs.So we can say Phanerochaete chrysosporium210 can accumulate and separate REEs.Biosorption kinectic results of Phanerochaete chrysosporium210 showed that the biosorption involved two phases. The first phase was very quick The other was a very slow process and the adsorption uptake capacity increased very slowly.The adsorption process tallies with Langmuir model and Freundlich equation. the Langmuir model well fitted this experimental data. The adsorption kinetics of REE by Phanerochaete chrysosporium210 is investigated. The result shows that adsorption process obeys the pesudo second-order kinetic model.更多还原