Study On Biosorption Of Heavy Metal By Saccharomyces Cerevisiae

The mine exploit, industry wastewater, garbage treatment and other human activity have a serious affection on our country's under water. So, it is a critical time todevelop a technology of low cost and high treatment effection. A study of Ag⁺,Co²⁺,Sr²⁺,Cs⁺ five ions adsorpted by S. cerevisiae on huge volume and low ions consistency wastewater which has been polluted by heavy metals. Creative points of the study are as follows:1,The experimental results indicated that, Cu²⁺ and Ag⁺ both uptake took place at the best pH range was 4-5; the best biosorption temperature of Cu was 20℃-30℃, temperature had no effect on the progress of Ag⁺ biosorption; there were two progresses of Cu²⁺ and Ag⁺ adsorption, the first was fast and it happened on the cell face mainly was physics adsorption and ion exchange, the second was slow, heavy metal enter cell through initiativr transport and consume metabolism energy. The capacity of Cu²⁺ almost 93.38% uptake was completed within the first ten minutes and the one of Ag⁺ almost was 86.6%; both ions biosorption time was 3 hours.2,The Langmuir and Freundlich adsorption isotherms can well described the progress biosorption of Cu²⁺, but the Langmuir adsorption isotherm was best, it's related coefficient was 0.999 42 and the adsorption equation was: q =7.928 33·c/(c +1/0.986 7); the isoadsorption of Ag⁺ accorded Langmuir isotherms, and Fredulich isotherm wasn't suit, the adsorption equation was: q = 49.7265·c/(c +1/0.00825) and its related coefficient was 0.98572.3,The adsorption ability of Sacchromyces cerevisiae on heavy metals was Sr²⁺>Co²⁺>Cs⁺ through comparation two of them mixed solitio, this maybe related with their moving morphology and the morphology of Cs⁺was simple ion Cs⁺,the one of Co²⁺ was mainly CoHCO₃⁺ and C₀²⁺·xH₂O,the one of Sr²⁺ was mainly SrHCO₃⁺and Sr²⁺·6H₂O.