Graduate School of Science and Technology, Niigata University, Ikarashi 2-nocho 8050, Nishi-Ku, Niigata 950-2181, Japan.
Bioinorg Chem Appl. 2010;2010:804854. doi: 10.1155/2010/804854. Epub 2010 Oct 25.
Biosorption experiment from aqueous solutions containing known amount of rare earth elements (REEs) using pre-treated Buccinum tenuissimum shell was explored to evaluate the efficiency of shell biomass as sorbent for REEs. In this work, four kinds of sieved shell samples: (a) "Ground original sample", (b) "Heat-treatment (480°C, 6 hours) sample", (c) "Heat-treatment (950°C, 6 hours) sample" and (d) "Heat-treatment (950°C, 6 hours) and water added sample" were used. Furthermore, to confirm the characteristics of the shell biomass, the crystal structure, the surface morphology, and the specific surface area of these shell samples were determined. Consequently, the following matters have been mainly clarified. (1) The crystal structure of the shell biomass was transformed from aragonite (CaCO(3)) into calcite (CaCO(3)) phase by heat-treatment (480°C, 6 hours); then mainly transformed into calcium oxide (CaO) by heat-treatment (950°C, 6 hours), and calcium hydroxide (Ca(OH)(2)) by heat-treatment (950°C, 6 hours) and adding water. (2) The shell biomass showed excellent sorption capacity for lanthanides. (3) Adsorption isotherms using the shell biomass can be described by Langmuir and Freundlich isotherms satisfactorily for lanthanides except "heat-treatment (950°C, 6 hours) sample". (4) Shell biomass (usually treated as waste material) can be an efficient sorbent for lanthanides in future.
采用预处理的宝螺壳从含有已知浓度稀土元素(REEs)的水溶液中进行生物吸附实验,以评估壳生物质作为 REEs 吸附剂的效率。在这项工作中,使用了四种过筛的贝壳样品:(a)“原始研磨样品”,(b)“热处理(480°C,6 小时)样品”,(c)“热处理(950°C,6 小时)样品”和(d)“热处理(950°C,6 小时)和加水样品”。此外,为了确认壳生物质的特性,测定了这些贝壳样品的晶体结构、表面形态和比表面积。结果,主要澄清了以下几点。(1)壳生物质的晶体结构由热处理(480°C,6 小时)从方解石(CaCO(3))转化为方解石(CaCO(3))相;然后主要由热处理(950°C,6 小时)转化为氧化钙(CaO),由热处理(950°C,6 小时)和加水转化为氢氧化钙(Ca(OH)(2))。(2)壳生物质对镧系元素表现出优异的吸附能力。(3)对于镧系元素,壳生物质的吸附等温线可以用 Langmuir 和 Freundlich 等温线很好地描述,除了“热处理(950°C,6 小时)样品”。(4)壳生物质(通常被视为废物材料)将来可能成为镧系元素的有效吸附剂。