包埋氧化亚铁硫杆菌的海藻酸钙凝胶扩散特性研究

Studies on Diffusion Properties of Alginate Gel Entrapped with Thiobacillus ferrooxidans Cells

采用非稳态法测定了FeSO4在未包埋氧化亚铁硫杆菌的凝胶中的有效扩散系数,分析包埋细菌的氧化情况。结果表明,FeSO4在凝胶中的有效扩散系数De随着海藻酸钠浓度的升高而降低,当海藻酸钠浓度为2%时最优;凝胶剂CaCl2的浓度对扩散系数的影响较小。包埋的氧化亚铁硫杆菌在10h达到增殖平衡,而FeSO4在包埋细菌的凝胶内扩散系数明显减少。包埋的氧化亚铁硫杆菌在初始铁浓度为5g/L时,完全氧化所需时间最短但氧化速率变化较快,当初始铁浓度为8g/L和10g/L时,完全氧化所需时间相同。

By non-steady method, the effective diffusivity of ferrous sulphate within alginate calcium gel entrapped without bacteria was measured. Meanwhile the oxidation ability of entrapped bacteria was analyzed. Experimental results showed that the effective diffusion coefficient of ferrous sulphate decreased with the increase of alginate concentration, the optimum alginate concentration is 2% （W/V）. The effect of calcium chloride on the effective diffusivity was neglectable. The incubation offerrooxidans would pass through 10 hours, and the diffusion coefficient within gel entrapped Thiobacillus ferrooxidans cells was less remarkably than that of ferrous sulphate without entrapped cells. For the entrapped cells, the absolute oxidation time was shortest and the rate change was fastest with the initial Fe concentration 5g/L. The absolute oxidation time was same when the initial Fe concentration was 8g/L and 10g/L.