液-液-液三相连续逆流萃取混合澄清槽工艺研究
文献类型：学位论文
| 作者 | 何秀琼 |
| 学位类别 | 硕士 |
| 答辩日期 | 2012-05-16 |
| 授予单位 | 中国科学院研究生院 |
| 导师 | 刘会洲 ; 黄昆 |
| 关键词 | 三液相萃取 分离 混合澄清槽 硝基苯酚 |
| 其他题名 | Process research of the continuous counter-current extraction in a three-liquid-phase mixer-settler |
| 学位专业 | 化学工程 |
| 中文摘要 | 近年来，液-液-液三相萃取技术发展迅速，但一直缺乏一种可行的三相连续萃取装置。本文提出一种新型三液相连续逆流萃取混合澄清槽，以含邻位硝基苯酚和对位硝基苯酚的模拟工业废水为分离对象，利用壬烷-PEG2000-硫酸铵-水构成的三相体系，考察了三相连续混合澄清槽连续萃取操作时，各种工艺操作参数对三液相萃取过程的影响。 本文提出的新型三相萃取混合澄清槽由三相混合室、澄清分相室、两相混合室三部分组成。其中，在澄清分相室内设有一个三相液流控制插件区以控制三相液流走向，可实现三液相体系的上、中、下三相两两逆流萃取操作。 为了简化实验对象，本文首先用烧杯实验模拟了三相萃取混合澄清槽三个室的运行状况，以忽略三相萃取混合澄清槽内各室之间的相互影响。结果表明，三相混合室内搅拌转速和搅拌时间影响两种硝基苯酚在三液相体系的分配效率。搅拌转速越大，目标物质达到萃取平衡状态就越快；搅拌时间越长，萃取率越高。萃取达到平衡后，约80%的邻位硝基苯酚被富集在上相，90%左右的对位硝基苯酚被富集在中相。搅拌转速对澄清分相室内三液相分散带厚度有很大影响。转速越大，三液相体系的上/中两相分散带消逝越慢，但中/下两相间相界面澄清速率基本不受搅拌转速影响。两相混合室内聚合物双水相体系的成相行为与体系盐浓度有关。当双水相体系中的硫酸铵浓度超过11%时，才能形成稳定的三液相。 实验考察了三相萃取混合澄清槽单槽连续运行时，各种操作参数对三相萃取分离两种硝基苯酚的影响。结果表明，当三相液流两两逆流操作时，上相与中下两相的进料流量比对三液相萃取传质有较大的影响。随着流量比增加，邻位硝基苯酚在上相的分配率先增大后减小，流量比为0.8时萃取率达到最大。对位硝基苯酚在中相的萃取率不受流量变化影响。流量比对槽操作达到稳定运行状态需要的时间也有影响。单槽连续运行120分钟达到三液相萃取平衡。邻位和对位硝基苯酚在上、中两相的萃取率分别达到80%和90%。 |
| 英文摘要 | Recently, the three-liquid-phase extraction technology developed rapidly. But it lacks of a feasible continuous three-liquid-phase equipment. This work proposed a new continuous counter-current three-liquid-phase extractor. The target system in this thesis was model industrial wastewater containing o-nitrophenol and p-nitrophenol, which was separated by the three-phase system consisted of nonane, PEG2000, (NH4)2SO4 and water. The thesis studied the key operation parameters of the proposed three-liquid-phase extractor which affected the process of the three-phase extraction at continuous operation condition. This proposed extractor consisted of three-phase-mixer, settler and two-phase-mixer three main parts. And there was a stream controller settled in the settler to control the three phases’ flow direction in order to accommodate different phase-combinations of the three phases for counter-current extraction. For the purpose of simplifying the experimental subjects, firstly, this work simulated the operation situation of the three chambers of the three-liquid-phase extractor to ignore the interference among the chambers. It is indicated that agitator speed and agitating time affect the distribution efficiency of the two nitrophenols in the three phases. Higher the agitator speed, faster for the extraction equilibrium state of the nitrophenols. Longer the agitating time, better the extraction rate. At equilibrium state, about 80% o-nitrophenol was extracted into the top phase, and 90% p-Nitrophenol was enriched into the middle phase. Agitator speed significantly affected the dispersion band of the three phases in the settler. Higher the agitator speed, more time needed for dispersion band between the top phase and the middle phase to disappear. And the agitator speed did not affect the clarification rate of the interphase between the middle phase and the bottom phase. It was indicated that the phase-forming behavior of the polymer-rich aqueous-two-phase system was related to the concentration of the salt. When the mass fraction of (NH4)2SO4 in the aqueous-two-phase system was higher than 11%, the system turned up two phases. The experiment researched the influence of operation parameters on the separating effect of the two nitrophenols when the single extractor running continuously. It was demonstrated that, while the counter-current operation of the three-phase-combinations, feed flow ratio (nonane/aqueous two-phase) affected the mass transfer among the three phases significantly. Along with the increasing feed flow ratio, distribution rate of o-nitrophenol rose at the beginning and got the highest before decreasing. The distribution rate of o-nitrophenol was optimal while the feed flow ratio was 0.8. The extraction rate of p-nitrophenol in the middle phase was not related to the feed flow ratio. The feed flow ratio affected the time needed for the equipment to reach steady state. Running for 120 minutes, it was able to reach extraction equilibrium for the equipment. At equilibrium state, the extraction rate of o-nitrophenol and p-nitrophenol were 80% and 90% respectively. |
| 语种 | 中文 |
| 公开日期 | 2013-09-25 |
| 源URL | [http://ir.ipe.ac.cn/handle/122111/1864]  |
| 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 | 何秀琼. 液-液-液三相连续逆流萃取混合澄清槽工艺研究[D]. 中国科学院研究生院. 2012. |
入库方式： OAI收割
来源：过程工程研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。