不同EPS组成生物膜对Cu^(2+)吸附的研究  

The research on biofilm composed by different EPS to adsorb Cu^(2+)

作　　者：胡学伟[1] 李姝[1] 荣烨[2] 李媛[1] 

机构地区：[1]昆明理工大学环境科学与工程学院,云南昆明650500 [2]昆明理工大学现代农业工程学院,云南昆明650500

出　　处：《中国环境科学》2014年第7期1749-1753,共5页China Environmental Science

基　　金：国家自然科学基金(51178208;51368024);云南省教育厅重点项目(2013Z123);昆明理工大学分析测试基金(20140549);云铜校企合作项目(2013YT02)

摘　　要：采用自行设计的反应器,通过调节培养液的配比对载体进行挂膜,得到蛋白质和多糖含量比分别为7:1、5:1和10:1的3种生物膜作为吸附剂,用其对Cu2+进行吸附试验,同时对吸附机理进行探讨.结果表明,培养8d后,生物膜可挂膜成熟,在C/N=12时,生物膜上的菌落数较C/N=4和C/N=37条件下多.PN/PS值越小,生物膜对铜的吸附量越高,EPS3对Cu2+的吸附量分别高出EPS1 7.37%,EPS2 7.62%.在生物膜吸附Cu2+后,溶液中Ca2+、Mg2+、K+含量明显升高,表明离子交换对生物膜吸附Cu2+起主要作用,且Cu2+更易与Ca2+和Mg2+产生离子交换作用.当KNO3浓度在0.1~0.6mol/L之间,随着离子强度的增加,生物膜吸附Cu2+的量迅速减少,当KNO3浓度大于0.6mol/L时,生物膜对Cu2+吸附量的变化趋于平缓,说明生物膜对Cu2+的吸附同时包括离子交换吸附和化学吸附.The biofilm were cultured in a self-designed reactor by adjusting the ratio of nutrients in order to get 3different biofilms as adsorbents for Cu^2＋, in which the proportion of protein and polysaccharide were 7：1, 5：1and 10：1respectively. This paper had a study on the adsorption of 3different bilfilms to Cu^2＋. Besides, the adsorption mechanism was discussed. The results showed that the biofilm became mature after 8days. When the value of C/N was 12, the biofilm grew better than that C/N was 4and 37, and the number of bacteria on it was more than the the number of bacteria on C/N =4and C/N=37. PN/PS value was smaller, and the adsorption capacity of Cu^2＋was higher. The amount of Cu^2＋ adsorbed on EPS3is higher than EPS1（7.37%） and EPS2（7.62%）. Cu^2＋ was absorbed on the biofilm, the concentration of Ca^2＋, Mg^2＋, K^＋ was significantly increased in the solution, demonstrating ion exchange play a main role during the adsorption and Cu^2＋ prefer to exchange with divalent Ca^2＋ and Mg^2＋. As the concentration of KNO3was from 0.1to 0.6mol/L, along with the increase of ionic strength, the Cu^2＋ content adsorbed on biofilm decreased rapidly. However, the concentration of KNO3is greater than 0.6mol/L, the change of Cu^2＋content adsorbed by biofilm trended to be gentle, the phenomenon showed that Cu^2＋ adsorption mechanism include ion exchange and chemical adsorption.

关 键 词：生物膜 胞外聚合物 碳氮比 铜 

分 类 号：X703[环境科学与工程—环境工程]