Mechanism of Flocculation Induced by Bioflocculant

Flocculating mechanisms of bioflocculant from agrobacteriumradiobacter is dealt with in this paper by flocculation tests and measuring Zeta potential of kaolin particle.It is demonstrated that Ca2+,Al3+,Fe3+ can improve flocculating efficiency by neutralizing charge on the surface of kaolin particles,and bettering adsorption of bioflocculant on the particles.Zeta potential curve of kaolin particle shifts down at the range of pH2.0～10.0 after addition of bioflocculant,therefore it is proved bioflocculant is partly composed of anion groups and its flocculating function is based on bridging not on the neutralizing charge.The flocculating activity remains almost unchanged when heated for half hour under different temperatures(40～100℃).It is showed that the functional component in the bioflocculant is not sensitive to the heat and the ultra-violet spectra is proved that the it is not comprise proteins and nucleic acid.