[Study of the factors of Cr(III) bioaccumulation on Spirulina platensis]

Some factors of Cr(III) bioaccumulation on Spirulina platensis were studied in detail. It was found that the bioaccumulation of Cr(III) on Spirulina platensis involved two steps: rapid adsorption and slow absorption. Chromic(III) compounds with weaker chemical bond had higher bioaccumulation efficiency. Under the same algal cell concentration, Cr(III) bioaccumulation rosed up with Cr(III) concentration. On the other hand, with Cr(III) concentration not changed, the total bioaccumulation of Cr(III) on Spirulina platensis increased with algal cell concentration, but the Cr(III) bioaccumulation on unit algae reduced. The study also showed that Spirulina platensis powder could bioaccumulate more Cr(III) than fresh Spirulina platensis, pH is a quite important factor and more suitable pH for Cr(III) bioaccumulation is 7. It was also proved that Cr(III) bioaccumulation benefited from the increase of temperature and light intensity. Cations had either stimulation or inhibition effects on the Cr(III) bioaccumulation on Spirulina platensis.