扩展DLVO理论
(中南大学 资源加工与生物学院， 长沙 410083)
摘 要: 根据Young's方程的推导公式结合接触角的测定结果计算黄铁矿和氧化亚铁硫杆菌的表面能参数。结果表明， 氧化亚铁硫杆菌的表面能明显高于黄铁矿的表面能。 应用热力学计算氧化亚铁硫杆菌在黄铁矿表面吸附的自由能， 发现其吸附自由能为正值， 无法解释氧化亚铁硫杆菌在黄铁矿表面的吸附现象，而通过扩展DLVO理论建立的Lifshitz-van der Waals（LW）、 Lewis acid-base(AB) 和静电（EL）作用自由能与作用距离（d）之间的势能曲线， 能够准确的预言氧化亚铁硫杆菌在黄铁矿表面的吸附现象。
关键字: 黄铁矿; 氧化亚铁硫杆菌；扩展DLVO理论； 表面能
（School of Resource Processing and Bioengineering,
Central South University, Changsha 410083, China）
Abstract: Surface energy parameters of pyrite mineral and Thiobacillus ferrooxidans were obtained by calculating according to deduced formula of Young's equation and contact angel. The results show that surface energy of Thiobacillus ferrooxidans is much higher than that of pyrite mineral. By thermodynamics approach, the interaction free energy of Thiobacillus ferrooxidans absorbed on the surface of pyrite was a positive value, which can not explain the adhesion behavior of the bacteria. However, the adhesion behavior can be exactly predicted by the potential energy graph of Lifshitz-van der Waals(LW) and Lewis acid-base(AB) and EL interfacial free energy as a function of separation distance(d), which were established on the base of extended DLVO theory.
Key words: pyrite mineral; Thiobacillus ferrooxidans; extended DLVO theory； surface energy
