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The heavy metal pollution is one of the world today is a very serious environmental pollution problems. This article related to Cr shall be a class of toxic heavy metals. The water bodies Cr is mainly trivalent and hexavalent compounds usually exist Cr3, CrO2-, CrO42-, Cr2O72-4 kinds of ionic form. The conventional processing method comprising: ion exchange, chemical precipitation, activated carbon adsorption, etc., suitable for the high-concentration wastewater treatment. When wastewater low concentration (LT; 100 mg / L), the processing efficiency is low, and high processing costs. Organisms to deal with the heavy metal has more advantage than physical chemistry, especially in low concentrations of heavy metals in waste water treatment, showed a higher efficiency. The common organism adsorbents, including bacteria, fungi, yeasts and algae. Wide range of sources, bio-materials cost. However, due to the the biosorbent small-scale, low-density, solid-liquid separation difficulties, its application in the field of heavy metal wastewater treatment is limited. As used herein, flocculation the yeast SPSC01 for excellent flocculation traits, has been put into industrial production of fuel ethanol fusion yeast, having characteristics of the particles formed self-flocculating. Adsorption mechanism of Cr (Ⅵ). The results prove, pH is the most important parameter in the adsorption process is restored, within a certain range, the pH is lower, and more conducive to the reduction of Cr (Ⅵ) to Cr (Ⅲ), the faster the adsorption equilibrium; pH the higher the better for Cr ( Ⅲ) adsorption, the higher the total chromium removal. Considering the to select pH 2 for the best treatment pH. Digestion of bacteria found adsorption equilibrium, adsorption to yeast on the Cr are Cr (III). The chemical shielding method of dealing with the adsorption effect of the yeast, contrast found that the surface of yeast play a major role for adsorbing group is an amino group, a carboxyl group and an amide group. Fourier transform infrared spectroscopy results also prove this result. Yeast component was separated, and measuring the proportion of each component adsorbed on the Cr, and observed by transmission electron microscopy, and found that adsorbed on the cell wall of most of the Cr, to prevent the entry of a large amount of Cr ions, reducing the biological toxicity of Cr on cells , even with the Cr (VI) reaction to reach equilibrium, SPSC01 still maintain a certain biological activity, can be adsorbed and then desorbed improve utilization. Were screened for desorption of 1 mol / L of HNO3 at 35 ℃ played a good desorption effect, which can be yeast recycling and the recovery of Cr An advantageous method.
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