固定化啤酒废酵母对Cr(Ⅵ)的吸附

Biosorption of Cr(Ⅵ) by immobilized discarded brewers yeast

用2%海藻酸钠与1%明胶混合作为包埋剂固定啤酒废酵母,研究固定化啤酒废酵母对Cr(Ⅵ)的吸附特性。结果表明,固定化啤酒废酵母吸附Cr(Ⅵ)受吸附时间、起始pH、固定化菌体浓度、Cr(Ⅵ)起始浓度及共存离子等因素的影响。确定固定化啤酒废酵母对Cr(Ⅵ)最佳吸附条件为:pH2,Cr(Ⅵ)起始浓度100 mg/L,固定化菌体浓度2 g/L,吸附90 min。此条件下Cr(Ⅵ)的吸附率可达96.8%。Pd2+等并存离子可抑制固定化啤酒废酵母对Cr(Ⅵ)的吸附。用1 mol/L盐酸洗脱固定化啤酒废酵母所吸附的Cr(Ⅵ)3 h,解吸率为93.6%。

Discarded brewers yeast was entrapped in a mixture of 2% sodium alginate and 1% gelatin, properties on biosorption of Cr（ Ⅵ ） by immobilized discarded brewers yeast were studied. It is shown that factors such as adsorption time, initial pH , immobilized biamass concentration, Cr（Ⅵ） initial concentration, co-ions, etc. affect adsorption process. The optimal adsorption conditions for immobilized discarded brewers yeast were as follows： pH 2, Cr（ Ⅵ ） initial concentration 100 mg/L, immobilized biamass concentration 2 g/L, adsorption time 90 min. Under these conditions, the biosorption efficiency of Cr（Ⅵ） was 96.8 %. Co-ions （e. g. Pd^2 ＋ etc. ） inhibited the Cr（ Ⅵ ） adsorption by immobilized discarded brewers yeast. 93.6 % of Cr（ Ⅵ ） could be recovered from immobilized discarded brewers yeast adsorbed Cr（Ⅵ） , desorbed with 1 mol/L HCl for 3 hours.