海洋细菌对稀土元素铈的富集矿化过程研究

Study on the enrichment and mineralization of rare earth element cerium by marine bacteria

采用从深海沉积物样品中分离培养的海洋微生物,分别进行几种海洋细菌(Jeotgalibacillus sp.,Paenisporosarcina sp.,Sulfitobacter sp.)对稀土元素Ce的富集成矿过程的模拟实验。实验过程中利用ICP-MS、SEM、TEM等分析测试手段考察了微生物与稀土元素的相互作用过程。结果表明,三种海洋细菌对稀土Ce都有吸附富集作用,海洋细菌吸附富集稀土元素Ce的效率主要与细菌密度和稀土元素浓度有关,不同的海洋细菌对稀土元素的富集能力也有所不同。海洋细菌吸附富集稀土Ce并矿化的过程中,稀土元素Ce首先被吸附在细胞表面形成成核点,随后在细胞表面被矿化形成含稀土Ce的非晶相结构的矿物颗粒。通过考察海洋细菌对稀土Ce的生物成矿过程,进一步探讨了海洋微生物富集稀土成矿的过程和作用机制。

Using Marine microorganisms isolated and cultured from deep-sea sediment samples,the accumulation and mineralization of rare earth element Ce by several marine bacteria(Jeotgalibacillus sp.,Paenisporosarcina sp.,Sulfitobacter sp.)were simulated.The interaction between marine bacteria and Ce was analyzed by inductively coupled plasma mass spectrometry(ICP-MS),scanning electron microscope(SEM),transmission electron microscopy(TEM),and other analytical methods.It was found that the three bacteria species could adsorb and enrich Ce,and the efficiencies of the adsorption and enrichment by the marine bacteria were mainly related to the bacteria density and the Ce concentration.In addition,the adsorption capacity of different marine bacterium to Ce was different.In the process of adsorption,enrichment,and mineralization of rare earth Ce by marine bacteria,rare earth Ce was first adsorbed at the cell surface to form nucleation cores,and then mineralized to form amorphous-structured mineral particles containing Ce on the cell surface.At last,the process and mechanism of rare earth mineralization enriched by marine microorganisms were further discussed.