吸附-磁性微生物降解耦合柴油脱硫脱氮工艺研究
文献类型：学位论文
| 作者 | 张婷 |
| 学位类别 | 硕士 |
| 答辩日期 | 2010-05-31 |
| 授予单位 | 中国科学院研究生院 |
| 授予地点 | 北京 |
| 导师 | 邢建民 |
| 关键词 | 生物脱硫 生物脱氮 γ-Al2O3 磁性固定化 耦合工艺 |
| 其他题名 | Desulfurization and denitrogenation by adsorption-magnetic microbial degradation integrated process |
| 学位专业 | 生物化工 |
| 中文摘要 | 石油中的含硫、含氮化合物不仅造成环境污染，还会导致炼制过程中催化剂中毒，微生物能够脱除石油中的含硫和含氮化合物。但微生物转化的速率较低是限制其应用的关键因素，因此本文以二苯并噻吩(Dibenzothiophene, DBT)和咔唑(Carbazole, CAR)为模型化合物，开展吸附-磁性微生物降解耦合脱硫脱氮工艺的研究。首先，利用吸附-磁性微生物降解原位耦合工艺脱除DBT。在细胞表面组装纳米Fe3O4磁性颗粒，进行磁性固定化，并在磁性固定化细胞表面组装吸附剂纳米γ-Al2O3。脱硫细胞的磁性固定化过程中细胞与磁性颗粒最佳质量配比为50:1；将磁性细胞应用于原位耦合脱硫，吸附性能较好，与细胞结合较紧密的γ-Al2O3具有较高的耦合脱硫活性；γ-Al2O3与磁性颗粒的质量比为5:1时，耦合脱硫活性最高，比磁性细胞脱硫活性提高近20%。磁性耦合脱硫细胞在重复使用三次之后，活性下降小于10%。其次，将吸附-磁性微生物降解原位耦合工艺应用于CAR的降解。使用表面活性剂Tween 80促进CAR在正辛烷中的分散，使溶解度增加到11 mmol/L；以此分散体系模拟油相，CAR降解速率有明显的提高；γ-Al2O3可以在2 min内完全吸附脱除11 mmol/L的CAR；磁性固定化脱氮细胞活性与游离细胞相当，耦合脱氮细胞重复使用时间超过210小时，活性下降22%左右，表现出良好的重复使用性能。利用吸附-微生物降解耦合同时脱硫脱氮。脱硫菌R. erythropolis LSSE-8-1-vgb和专一性CAR降解菌Klebsiella sp. LSSE-H2的混合细胞对模拟柴油进行同时脱硫脱氮时，3 mmol/L DBT可以在12 h内被完全脱除；γ-Al2O3在4 min内完全脱除模拟油相中的DBT和CAR。使用吸附-微生物降解耦合的方法同时脱硫脱氮，对吸附剂进行生物再生之后重复使用，在6 min内可以完全脱除模拟油相中的3 mmol/L DBT和11 mmol/L CAR。 |
| 英文摘要 | To meet further stringent environmental standard, ultra-deep removal of sulfur and nitrogen from transportation fuels has become very imperative for the petroleum refining industry. The presence of sulfur and nitrogen compounds in fossil fuels not only affects the quality of the petroleum product, contributes to the formation of oxides and causes severe environmental pollutions, but also poison catalysts. This study focused on the desulfurization and denitrogenation by a microbial-adsorption integrated process. Magnetic microbial degradation-adsorption in-situ integrated process was developed in desulfurization of DBT. Magnetical immobilization was carried out by assembling Fe3O4 nano-particles onto the cells, and then adsorbent γ-Al2O3 was assembled on the magnetic cells. The optimal ratio of cells to magnetic particles was determined to be 50:1. Adsorbent γ-Al2O3 with better adsorptive capacity and stronger combination force with the cells had a higher desulfurization activity. The optimal ratio of γ-Al2O3 to magnetic particles was 5:1, when the activity was increased about 20%, the activity decreased les than 10% after 3 testing cycles. Then magnetic microbial degradation-adsorption in-situ integrated process was utilized in denitrogenation of CAR. With the help of Tween 80, carbazole was well-dispersed and achieved concentration of 11 mM in n-octane as model oil for bionitrogenation. Biodegradation rate of free cells increased 20%. Cells were magnetically immobilized by coating with Fe3O4 nano-particles and were recollected by an external magnetic field conveniently. Biodenitrogenation activity of magnetically immobilized cells was almost the same as the free cells. The magnetic cells can be reused. The activity decreased less than 23%after three recycles for 210 hours. The desulfurization and denitrogenation was carried out by microbial degradation -adsorption integrated process. Mixed cells of R. erythropolis LSSE-8-1-vgb and Klebsiella sp. LSSE-H2 were used to remove sulfur and nitrogen-containing conpounds from model oil, 3 mmol/L DBT was thoroughly removed in 12 h. γ-Al2O3 can remove all DBT and CAR in 4 min. The adsorbent was bioregenerated and reused in adsorption of DBT and CAR, 3 mmol/L DBT and 3 mmol/L CAR could be removed thoroughly in 6 min. |
| 公开日期 | 2013-09-17 |
| 页码 | 85 |
| 源URL | [http://ir.ipe.ac.cn/handle/122111/1519]  |
| 专题 | 过程工程研究所_研究所（批量导入） |
| 推荐引用方式 GB/T 7714 | 张婷. 吸附-磁性微生物降解耦合柴油脱硫脱氮工艺研究[D]. 北京. 中国科学院研究生院. 2010. |
入库方式： OAI收割
来源：过程工程研究所
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