固定化细菌降解氰化物培养条件的研究

DEGRADATION OF CYANIDE BY IMMOBILIZED BACTERIUM AND ITS CULTURE CONDITIONS

采用海藻酸钙法对9#细菌进行固定化。通过四因素三水平的正交试验,确定了固定化的最优组合,并利用此最优组合固定细菌,对氰化物的降解进行研究。考察了培养时间、培养温度、pH、氰化物浓度、菌量、重复利用等对氰化物降解效果的影响。实验结果表明,固定化最优操作条件为:海藻酸钠3%,CaCl23%,钙化时间4h,菌量5mL,固定化细菌培养20h后氰化物降解率可达93.92%。固定化细菌最适降氰条件为:pH6.0,温度34℃,菌量9g。随着氰化物浓度的增加降氰率逐渐降低。固定化小球经过5次重复利用后,其氰化物降解率仍达92.29%。

Through four factors and three levels orthogonal design experiment, the optimal preparation condition for the strain 9# immobilized with sodium alginate was obtained in this study. At the same time, the effects of various parameters on the biodegradation of cyanide by the bacterium, such as culture time, temperature, pH value, concentration of cyanide, biomass, and reuse were investigated. It was shown that under the optimal preparation conditions of 3% sodium alginatc, 3%CAC12, 4 h calcifying time, 5 mL biomass, the cyanide degradation ramtc could teach to 93.92% by the immobilized bacterium after 20h.Thc optimum pH, temperature and immobilized bacterium amount wcrc 6.0, 34℃ ,and 9g tespectivcly. The degradation ratc decreased gradually with increase of cyanide concentration. The immobilized bacterium could bc reused after degrading for five times, and the degradation rate could still teach to 92.29%.