Biosorption Of Cu～(2+) And Hg～(2+) On Candida Utilis By Negative Pressure Cavitation From Polluted Water

Cu²⁺ and Hg²⁺ are the impotent two kinds of heavy metals ion in polluted the water. This article mainly studied the biological adsorption effect of Candida Utilis to the Cu²⁺ and Hg²⁺ in water, through the experiment we determined and established two biosorption models---Langmuir and the Freundlich. Has determined several primary factors for the influence adsorption efficiency, Including the water pH of water which includes the Cu²⁺ and Hg²⁺; The most suitable density of Candida Utilis; The most suitable density of water; And the best adsorption time. The research demonstrated: the best adsorption condition is Cu²⁺:pH=4.54～5.04, [Candidauti]:[Cu²⁺] = 60:1; Hg²⁺:pH=2.96～3.48, [Candidauti]:[Hg²⁺] = 40:1. After determined these kinds of primary factors, we has contrast studied the strengthen function of the the vacuum cavitations for biosorption.This article also used some Instruments such as spectrophotometer and laser focusing microscope, from molecular level discussed the Cu²⁺ Or Hg²⁺ distributed situation around adsorption inside and outside yeast cell, the pH change of inside cell around adsorption, and the microscopic change of Candidauti surface around adsorption. Obtained the biological adsorption process mainly to divide into two steps, first was a quick process, then was a slow process; Under the concurrent present atmospheric pressure, the yeast Cu²⁺ or Hg²⁺ which Adsorption by table mainly distribute in the extra cellular, the cell internal is not basic. But the vacuum cavitations adsorption Cu²⁺ or Hg²⁺ exist inside and outside yeast's cell. And along with adsorption carrying on, in the yeast cell the pH has along with the adsorption time increase elevates, Becomes the weak basicity by the acidity. And along with adsorption rate increasing, The pH of its cell has also increased.