摘要:通过海藻酸钠-生物炭联合固定化芽孢杆菌H3菌株去除水中的Pb以及Cd,为重金属污染水体的生物修复提供材料和技术。本次试验通过海藻酸钠溶液联合生物炭和芽孢杆菌H3,在0。5mol·L-1的氯化钙溶液中交联制备固定化小球。通过两组交叉试验,对固定化小球的制备进行研究发现,在生物炭含量为0。2%、菌悬液添加量为3%的条件下制得的固定化小球的吸附能力最强,且对水中铅浓度的降低率达到97%,优于对镉的去除。生物炭联合芽孢杆菌H3菌株固定化小球在初始浓度分别为10 mg·L-1、20 mg·L-1、30 mg·L-1的Cd及Pb溶液中降低铅浓度的速度都优于镉溶液中,在30 min时即可吸附50%以上的铅。结果表明本试验制备的生物炭联合芽孢杆菌H3固定化小球具有优良的吸附铅镉特性和生物修复潜力。86094
毕业论文关键词:生物炭;芽孢杆菌;固定化小球;重金属污染
Absorption of Cd or Pb in the water and reparation through biochar immobilized Bacillus megaterium H3
Abstract: The absorption of Pb or Cd in water by immobilized Bacillus megaterium H3 strain by sodium alginate and biochar was used to provide a theoretical basis for the stable and efficient degradation of Pb and Cd in water。 In this experiment, sodium alginate solution was combined with B。 megaterium H3, and the reaction time was obtained in the reaction solution of 0。5 mol L-1 calcium chloride solution for a period of time。 Two groups of cross experiments were conducted to study the preparation of immobilized pellets。 It was found that the adsorption capacity of immobilized beads was the strongest when the content of biochar was 0。2% and the amount of bacterial suspension was 3%。 The addition of bacterial suspension mainly affected the adsorption efficiency of immobilized beads, while the final adsorption rate increases slightly。 The optimum immobilized beads prepared under the condition of choice were added to the solution containing 10 mg·L-1, 20 mg·L-1, 30 mg·L-1 Cd or Pb respectively。 The results were found that the adsorption of immobilized rate only slightly decreased, the adsorption capacity of immobilized unit weight corresponding to the straight up。 According to the relevant research, it is found that the spherical adsorption material has a larger internal pore, which is beneficial to promote the adsorption of metal ions。
Key words: Biochar;Bacillus megaterium;heavy metal pollution;immobilized cells
目 录
摘要2
关键词2
Abstract3
Key words3
引言(或绪论)4
1 材料与方法4
1。1 材料 4
1。2 细菌悬液的制备 4
1。2。1 芽孢杆菌活化4
1。2。2 制备细菌悬液4
1。3 制备固定化小球5
1。4吸附试验5
1。5样品中重金属铅镉的测定5
1。6 数据处理铅镉的测定3
2 结果与分析5
2。1 细菌悬液及固定化小球的部分性质5
2。2 不同生物炭添加量固定化小球吸附溶液中铅镉的作用6
2。3 芽孢杆菌H3不同添加量固定化小球吸附溶液中铅镉的作用7
2。4 在不同铅和镉浓度下生物炭协同H3固定化小球的吸附作用8
3讨论9
致谢10
参考文献10
生物炭固定化芽孢杆菌的制备和活性
恢复一个失衡水系统生态最彻底的方法是采用生物修复技术。生物炭是一种新型的生物修复材料,能够同时吸附环境中的有机污染物以及重金属污染物。芽孢杆菌作为一种土壤和水环境中常见的细菌,一直是净水研究的应用热点[1]。但直接使用微生物游离细胞的弊端很多,如细胞易被水流冲走、利用率低下,而且由于培养基的带入而引起二次污染等;加之在自然环境中,水中的重金属以及有机污染物绝大部分沉积在底部,不易被吸附或降解。因此需要利用合适的固定化载体,使添加的作用菌株更多地随载体到达底部,并在池底生长繁殖,以达到更好地降解池底污染物的目的[2]。