金针菇菌柄非食用部分对镉的生物吸附

Study on biosorption of Cd^(2+) by means of testing Flammulina velutipes

采用金针菇(Flammulina velutipes)除去其可食用部分后剩余的废弃部分菌粉作为生物吸附剂吸附Cd2+,研究金针菇吸附Cd2+的理想条件。试验评价了5个影响因子:样品的不同处理方式,振荡吸附时间,溶液pH值,Cd2+初始浓度和菌粉投加量。结果表明,菌粉颗粒越细,吸附能力越强;振荡时间对吸附的影响不显著;pH值是影响金针菇吸附能力的关键因子,pH值为7时达到最大吸附率(63.1%);吸收60min时,金针菇对Cd2+的吸附率最高(71.9%);随着溶液初始Cd2+浓度的增加,吸附率降低,但随菌粉生物量的增加,吸附能力上升;当溶液Cd2+的浓度为80mg.L-1时,最大吸附量达到5.573mg.g-1。可以认为金针菇菌柄非食用部分是一种有效的生物吸附剂。

The paper is aimed to present its authors＇ study and finding of the optimum conditions for Cd^2＋ biosorption property, for which purpose we have conducted a test by using the waste left-over part of Flammulina velutipes as a biosorbent. As a result of our study, we have found that there are 5 main factors that affect the adsorption capacity of F. velutipes, that is, the sample treating methods, pH value of solution, shaking time, initial concentration of metal ion and the dosage of mycelium used. The results of our study also indicate that, the thinner the fungus powder pellet, the greater the adsorption capacity. What is more important, the initial pH proves to be the key factor that influences the adsorption capacity of F. velutipes. When the initial pH was 7, the adsorption rate would reach the maximum （63.1% ）. And, 60 min later, the adsorption capacity of F. velutipes on Cd^2＋ would reach the highest value （71.9%）, On the contrary, the adsorption rate would decrease with the increase of the initial Cd^2＋ concentration of the solution, and increase with the increase of the biomass of the mycelium. When the mass concentration of Cd^2＋ in the solution was 80 mg/L, the adsorption strength would come to the maximum value （5.573 mg/g）. However, the shaking time proves to have little or no effect on the biosorption.