多级错流液液萃取法分离醋酸水溶液的研究

以醋酸正丙酯—正丙醇—NaCl的复合溶液为萃取剂,采用多级错流液液萃取法对醋酸水溶液进行分离。考察了静置时间、溶剂比及萃取级数对分离效果的影响。实验结果表明:当静置时间为60 min,溶剂比(S/F)为3∶1时,经过三级错流液液萃取后,萃余相中醋酸的质量含量为0.54%。文章研究结果为进一步研究提供了基础数据。     

多级错流萃取分离丙酸甲酯-甲醇-水体系的模拟及实验研究

设计了丙酸甲酯-甲醇-水体系错流萃取分离工艺,通过实验选择了丙三醇-水的复合溶剂作为分离丙酸甲酯-甲醇-水体系的最佳萃取剂。以UNIQUAC方程为计算活度系数模型,采用色谱法测定了甲醇在丙三醇中的无限稀释活度系数,并运用单参数法计算了UNIQUAC方程中的相互作用参数。采用相分配系数和物料平衡方程对整个错流萃取过程进行了模拟计算。实验及模拟结果表明:当静置时间为20min,萃取剂中水与丙三醇的体积比为1.0,溶剂比为1.5时,经过三级错流萃取,丙酸甲酯的质量分数达到99.5%以上,收率达98%,且实验值和模拟值之间基本一致。     

液液萃取分离乙酸甲酯与甲醇水溶液的模拟计算

设计了乙酸甲酯和甲醇水溶液错流萃取分离工艺,通过实验确定了以甘油和水的复合溶液作为分离乙酸甲酯和甲醇水溶液的最佳萃取溶剂。以UNIQUAC方程为计算活度系数的模型,采用色谱法测定了甲醇在甘油中的无限稀释活度系数,并利用单参数法计算UNIQUAC方程中的模型参数。采用相分配系数和物料守恒方程模拟错流萃取分离过程,建立了模拟计算程序框图。将模拟值和实验值进行比较,相对误差仅为0.01%。模拟结果表明:在理论级数N=3时,经过一次萃取乙酸甲酯质量分数可达99.7%以上,收率达97.0%,此结果为进一步研究提供理论依据。     

反应精馏和液液萃取结合合成二甲氧基甲烷

以对甲苯磺酸为催化剂,以甲醇、甲醛为原料,采用反应精馏合成二甲氧基甲烷,二甲氧基甲烷的质量分数达到92%以上;采用液液萃取法对产物进一步提纯,研究液液萃取过程中,转速、搅拌时间、静置时间、溶剂比等因素对分离过程的影响,二甲氧基甲烷的收率可以达到90%以上;经一级萃取,二甲氧基甲烷的纯度可达到97%以上,二级萃取纯度可达到99.3%以上,萃取剂经处理,可循环使用;并对结果进行关联,关联和实验结果平均相对误差均小于1%,其结果为进一步放大实验研究提供依据。     

多级错流萃取法从粗品茄尼醇皂化液中提取茄尼醇的研究

采用液液萃取法从茄尼醇皂化液中提取茄尼醇,对茄尼醇皂化液的萃取条件进行研究,探讨了萃取剂的用量、萃取温度、萃取时间及萃取级数对多级错流萃取过程的影响,并进行正交实验.结果表明5.0 g粗品茄尼醇经皂化,加人100 mL萃取剂、温度控制为30℃、萃取时间设汁为45 min、经过三级错流萃取,并脱除萃取溶剂,可得到70%以上的茄尼醇,分配系数为27.58.     

水-二乙氧基甲烷-乙苯/苯甲醚的液液相平衡

为了探索不同萃取剂萃取分离水-二乙氧基甲烷共沸物的能力,在大气压力下,以乙苯和苯甲醚为萃取剂,分别测定了303.15和313.15 K时水-二乙氧基甲烷-乙苯/苯甲醚体系的液液相平衡数据.通过计算所得分离因子远大于1,表明乙苯和苯甲醚均为此体系的优良萃取剂.使用Othmer-Tobias和Hand经验方程对实验数据进行...     

苯酚羟化液多级萃取分离及磷酸三丁酯配合萃取过程

针对甲基异丁基甲酮(MIBK)和异丙醚(DIPE)两种萃取剂以及在不同剂溶比时萃取苯酚羟化液的萃取效果进行了比较;并进一步采用磷酸三丁酯(TBP)为配合剂、甲基异丁基甲酮(MIBK)为稀释剂研究了苯酚羟化液的配合萃取.结果表明:MIBK的萃取效果优于DIPE,MIBK为萃取剂时的最优剂溶比为1:3,此时苯酚羟化液的三级错流萃取率可达99%发上.通过MIBK对羟化液的多级错流萃取过程模拟计算进一步验证了此结论.采用TBP络合萃取苯酚羟化液,实验表明,萃取率可达到99.76%.     

煤基石脑油萃取脱芳制备溶剂油工艺研究

以中低温煤焦油加氢生成的石脑油(煤基石脑油)为原料,在萃取温度40℃、萃取剂和原料体积比(剂油比)1.5∶1、萃取时间5 min、分相时间20 min的工艺条件下,探究不同萃取剂对液-液萃取脱芳效果的影响,其中复合萃取剂V(二甲基亚砜,DMSO)∶V(N,N-二甲基甲酰胺,DMF)=9∶1时脱芳效果较好,然后选择此萃取剂研究各工艺过程参数对脱芳效果的影响。通过单因素考察和响应面分析得到液-液萃取脱芳的最优工艺条件为:萃取温度为44.48℃,单级剂油比为1.69∶1,萃取时间为5.30 min,分相时间为10 min,在此工艺条件下,经5级错流萃取,原料的芳烃脱除率可达(89.51±0.03)%,溶剂油收率为(73.33±0.03)%。     

置换液液分散微萃取测定水样中的痕量镉

首次采用置换液液分散微萃取法分离富集环境水样中痕量镉.在实验中,分别对萃取剂、分散剂、被置换剂的种类、配合剂二乙基二硫代氨基甲酸钠(DDTC)的浓度、水-分散剂-有机萃取剂三者的体积比,以及溶液的酸度进行了优化.得到的最佳实验条件为:在pH 6左右时,四氯化碳、丙酮、ZH2分别为萃取剂、分散剂和被置换剂,DDTC配合浓度为0.003％,水相、丙酮和四氯化碳的体积分别为5.00、0.50 mL和90μL.在上述确定的实验条件下,成功测定了复杂水样中痕量镉,方法的检出限为0.005 μg/L,回收率为92.5％ ～ 109％.     

连续多级逆流液液萃取与减压精馏集成分离α-酮亮氨酸和水的方法及其设备

连续多级逆流液液萃取与减压精馏集成分离α-酮亮氨酸和水的方法及其设备:首先以萃取剂对含10%α-酮亮氨酸水溶液进行多级逆流液液萃取,萃取分离后,液液萃取塔底水相送至水处理塔,水处理塔塔顶溶剂循环使用,水处理塔塔底水送至废水池,液液萃取塔顶萃取相为萃取剂和α-酮亮氨酸的混合液,送至连续减压精馏塔处理,连续     

Mass Transfer in Liquid–Liquid Systems

A formal criterion for determining the phase controlling mass transfer in liquid–liquid systems is proposed. Experimental data on mass transfer in the continuous phase are generalized for the external and mixed mass-transfer problems.     

Liquid–Liquid Equilibria in Biodiesel Production

During biodiesel production, the product is contaminated with impurities such as some non-reacted alcohol, glycerol, and catalyst. In order to comply with product requirements, these impurities must be removed, for example, by washing with water. Knowledge of the extent of water solubility in biodiesel is required to design the drying system and determine fuel quality. In the present work, the solubilities of water in biodiesels produced from sunflower and canola oils were measured within the temperature range of 24–60 °C. The solubility of water increased with increasing temperature and biodiesel unsaturation. The liquid–liquid equilibria of ternary systems of glycerol, methanol, and the above-mentioned biodiesels were investigated experimentally at 20, 30, and 40 °C. The binodal curves were determined by using the cloud point titration method and the tie lines were measured by evaporating the methanol. Both binary and ternary data were modeled using the UNIQUAC model. The model showed good agreement with the data. Othmer-Tobias correlations were applied and the corresponding constants were obtained. The results validated the consistency of the tie-line data obtained experimentally.     

Recovery of Furfural from Aqueous Solution by Ionic Liquid Based Liquid–Liquid Extraction

Abstract

Liquid–liquid extraction with imidazolium based ionic liquids ([C₄mim][PF₆], [C₆mim][PF₆], and [C₈mim][PF₆]) is proposed for the separation of furfural or 5-methylfurfural from aqueous solution. Factors affecting the extraction of furfural or 5-methylfurfural have been studied. It was shown that the extraction equilibria can be achieved within 30 min and the process was less affected by the factors such as volume ratio and feed concentration. The partition coefficients of furfural and 5-methylfurfural decreased with increasing temperature. [C₆mim][PF₆] was found to have the best extraction ability among the three ionic liquids studied. Presence of small amount of NaCl or Na₂SO₄ in the aqueous phase results in the considerable increase in the partition coefficients of furfural because of the competitive hydration of the salts with furfural. A thermodynamic study revealed that the extraction process was driven mainly by hydrophobic interactions. Further experimental results indicated that furfural can be separated selectively from aqueous furfural/acetic acid mixtures.     

Separation of Liquid Solutions by Contained Liquid Membranes

Abstract

The technique of contained liquid membranes (CLM) for liquid solution separation is discussed. The CLM is obtained by confining the membrane liquid between two sets of microporous hollow fibers (MHF). The lumen of the hollow fiber carries the feed or the strip solution under proper phase pressure condition vis-a-vis the membrane phase. Various possible structural configurations of the CLM are illustrated with respect to the nature of microporous hollow fiber substrate, the feed solution and the liquid membrane. The contributions of different resistances to the solute transport rate are identified. Some basic experimental data obtained in small CLM permeators are presented for two systems with organic liquid membranes to illustrate how steady state separation is achieved after an initial unsteady period. The considerable advantages of the CLM structure over more traditional liquid membrane techniques such as supported liquid membrane (SLM) with respect to membrane stability, membrane regeneration and feed equilibration are pointed out.     

Electrostatic Drop Formation in Liquid/Liquid Systems

Electrostatic drop formation in liquid/liquid systems was studied, using high frequency AC fields (45 kHz). The dispersion of nonconductive into conductive fluids was investigated under various conditions, as are the effect of aqueous phase conductivity, capillary geometry and organic phase viscosity on the resulting drop size. The experimentally determined drop sizes and literature data, were correlated with a model equation, which was derived from a simple force balance, with an empirical term for the electric force. The model parameters were obtained in a toluene/water system and the model allows the prediction of the drop sizes of other organic solvents, if the capillary geometry is kept constant.     

液体皂

人类使用皂类产品已有三千多年的历史,由于人类的进步和科学技术的现代化皂类产品不断变化,从块状产品到粉状、液体等,由于肥皂本身的缺陷和适用性比较差,逐步退出洗涤用品市场,美国在1955年合成洗涤剂的产量大于肥皂;日本在1965年,我国在1985年,2002年我国肥皂和合成洗涤剂总产量为3846052吨,其中肥皂占14.6%为56163吨,比2001年下降了16.23%,但是皂类产品并不是一无是处,它来源于再生资源,符合继续再发展的国策和世界的潮流,它易被生物降解,是其他表面活性剂(SAA)莫所及的,它无毒不妨碍人身健康,若改其不耐硬水的缺陷提高去污力是有其发展前途的,特别是液体皂.     

Liquid Quasicrystals

In the first part, this brief review discusses the discovery of the first example of supramolecular dendritic liquid quasicrystal, which represents also the first example of soft quasicrystal. In the second part, we show that soft quasicrystals generated from supramolecular spheres are scattered through libraries of self-assembling dendrons, dendrimers, and dendronized polymers. The supramolecular spheres forming soft quasicrystals are generated via at least two different mechanisms, and are chiral. Generation of quasicrystals from other organic building blocks is also discussed. Finally, potential applications in electronics, sensors, and as ionic liquid-based nanoreactors are also mentioned.     

槽式液体分布器均布性能CFD模拟的可视化研究

针对适用于规整填料的槽式液体分布器的初始布液性能,在现有的经验参数基础上,作者利用商业计算软件FLUENT对特定条件下的液体分布时的流动情况进行数值模拟计算,所得结果基本符合实验情况.