钾细菌对钾长石胶体吸附特性的影响研究

Effect of Potassium Bacteria on the Adsorption of Potassium Feldspar Colloid

土壤硅酸盐细菌能够分解含钾硅酸盐矿物,可有效缓解我国农田土壤有效钾不足的问题.对硅酸盐细菌与含钾矿物表面的交互作用的研究有助于了解土壤硅酸盐细菌解钾的作用机制与效率.选取硅酸盐矿物钾长石和硅酸盐细菌,通过DLVO理论和扩展DLVO理论分别计算出钾长石胶体体系、钾长石-钾细菌混合体系颗粒间的相互作用力,探讨钾细菌对钾长石胶体吸附特性的影响.研究结果表明:钾长石-钾细菌混合体系对亚甲基蓝的吸附量明显大于钾长石对亚甲基蓝的最大吸附量.细菌比表面积大,加入钾长石胶体中,形成的钾长石-钾细菌复合物的比表面积增大,导致钾长石-钾细菌混合体系吸附反离子的能力增大,屏蔽电场的强度增强,静电斥力减弱,吸引力增加,从而提高了吸附强度.

The silicate bacteria can decompose potassium-containing silicate minerals,which can effectively alleviate the problem of insufficient of soluble potassium in the farming soil.But the interaction between silicate bacteria and the surface of potassium-containing mineral is still lack of understanding.To investigate the effect of potassium bacteria on the absorption characteristics of the potassium feldspar colloid,the silicate mineral-potassium feldspar and silicate bacteria were chosen for our study,calculated the interactions between particles in potassium feldspar colloid system and potassium feldspar-potassium bacteria mixed system by DLVO theory and extended DLVO theory,respectively.The results showed that the adsorption of methylene blue in potassium feldspar-potassium bacteria mixed system is significantly higher than the potassium feldspar maximum adsorption of methylene blue.Bacteria with large specific surface area were added into the potassium feldspar colloid,and formed the potassium feldspar-potassium bacteria compound also with large specific surface area,and thus led to the enhanced capability of adsorbing counter ion and shielding the electric field,electrostatic repulsion abated coupled with attraction increased in potassium feldspar-potassium bacteria mixed system,and consequently improved the adsorption capability.