Abstract:

This study isolated and acclimatized a benzene-degrading bacterium, Bacillus cereus YJ-2, from contaminated sites using benzene as the sole carbon source,and biochar coupled with microbial technology was used to enhance the degradation of benzene-containing wastewater. By optimizing the degradation conditions of YJ-2, the degradation effects on different substrates was investigated, the optimal biochar addition was determined, and the benzene degradation capability of the coupled system was assessed, expecting to obtain bio-materials with promising applications. Results showed that under the optimized conditions of pH=8, OD₆₀₀=0.2, temperature of 30 ℃, and initial benzene concentration of 500 mg/L, YJ-2 exhibited the best benzene degradation efficiency. It also showed degradation rates of 77.5% for toluene, 59% for ethylbenzene, 72.3% for chlorobenzene, and 61.8% for ortho-dichlorobenzene. Furthermore, the optimal biochar addition in the coupled system was determined to be 0.5 g/L,achieving a degradation rate of 100% for 1 000 mg/L benzene, while enhancing YJ-2's ability to degrade 1 500 and 2 000 mg/L benzene by over 20%. When applied to simulated real wastewater, the degradation efficiency of the coupled system was significantly higher compared to using YJ-2 alone. Notably, in high concentrations of 1 000, 1 500, 2 000 mg/L, YJ-2's degradation activity decreased by 26.8%, 21.5%, and 4.95%, respectively, while the coupled system increased by 31.7%, 12.65%, and 15.55%. These results indicated that biochar coupled with YJ-2 technology provided a viable method for addressing benzene pollution in the environment.

Key words: biochar, coupled microorganism, benzene, degradation

摘要：

以苯为唯一碳源，从受污染场地驯化、筛选出一株高效苯降解菌Bacillus cereus YJ-2，并利用生物炭耦合微生物技术强化降解含苯废水。通过对YJ-2降解条件进行优化，研究了YJ-2对不同底物的降解效果，确定生物炭的最适投加量，并考察耦合体系对苯的降解能力，期望获得具有应用前景的生物材料。结果显示，在pH=8，OD₆₀₀=0.2，温度为30 ℃，苯初始质量浓度为500 mg/L的最优条件下，YJ-2对苯具有最佳的降解效果，同时对甲苯、乙苯、氯苯、邻二氯苯的降解率分别为77.5%、59%、72.3%、61.8%。在此基础上，确定了耦合体系中生物炭的最适投加量为0.5 g/L，对于1 000 mg/L苯的降解率可达100%，且将YJ-2降解1 500、2 000 mg/L苯的能力提升20%以上。将该体系应用于模拟实际废水中，降解效率显著优于单独使用YJ-2的情况，其中，在添加1 000、1 500、2 000 mg/L的高质量浓度苯组分的实验组中，YJ-2的降解活性大大降低，分别降低了26.8%、21.5%、4.95%，而耦合体系增加了31.7%、12.65%、15.55%。这一结果表明，生物炭耦合YJ-2技术为解决环境中苯污染问题提供了良好的生物修复材料。

关键词: 生物炭, 耦合微生物, 苯, 降解

CLC Number: 

• X703.1