Extracting Performance of Cesium by 25,27‐Bis(2‐Propyloxy) Calix[4]‐26,28‐Crown‐6 (iPr‐C[4]C‐6) in n‐octanol

Abstract

In this work, the extraction of cesium(Cs⁺) in nitric acid and in a simulated high level liquid waste (HLLW) by iPr‐C[4]C‐6 was investigated in the diluent n‐octanol. The slope of the extractant dependency equals 1, indicating that the complex has 1∶1[Cs⁺ · iPr‐C[4]C‐6]Cs⁺ to ligand. 0.025 mol/L iPr‐C[4]C‐6 in n‐octanol (abbreviated to iPr‐C[4]C‐6‐n‐octanol) has a stronger extracting ability to Cs when acidities are between 1.0 mol/L and 4.0 mol/L. The stripping properties of Cs loading in 0.025 mol/L iPr‐C[4]C‐6‐n‐octanol was studied. Cs loading in iPr‐C[4]C‐6‐n‐octanol can be stripped easily into the aqueous phase because the distribution ratios of Cs are lower than 0.5 when pH is between 2 and 10 in the aqueous phase. On the above basis, the better parameters were selected and the cold cascade test for removing Cs from the simulated HLLW was investigated on miniature centrifugal contactor. The results of the test are attractive. The removing ratio of Cs from the simulated HLLW is 99.5% and the stripping ratio of Cs loading in 0.025 mol/L iPr‐C[4]C‐6‐n‐octanol is 99.2%. The results show that 0.025 mol/L iPr‐C[4]C‐6‐n‐octanol is an effective process for removing Cs from HLLW.     

Separation of Monoester and Diester in the Esterification Product of Polyethylene Glycol and Acrylic Acid by the Weibull Method

In the extraction system of ethyl acetate and NaCl aqueous solution, partition coefficients of polyethylene glycol mono-acrylate (PEGmA) and polyethylene glycol di-acrylate (PEGdA) varied with temperature and concentration of NaCl solution were studied. The best separation condition of PEGmA and PEGdA was determined on that basis. Results of the testing showed that partition coefficients of PEGmA and PEGdA sharply increased with rising concentration of NaCl solution and temperature. Since the incremental degrees of PEGmA and PEGdA were different from each other, the ratio of partition coefficient (K _PEGdA/K _PEGmA) reached a maximum under the conditions of 20 °C and 5 mol L⁻¹ NaCl. The best separating condition was as follows: PEGdA was extracted out with ethyl acetate by adding 5 mol L⁻¹ NaCl at 20 °C. After three repetitions, the recovery rate of PEGdA reached 99.8%. The water phase was heated to 50 °C and PEGmA was extracted out with ethyl acetate. The recovery rate of PEGmA amounted to 68.8% by three repetitions. After washing and drying, the purity of PEGmA and PEGdA was 99.7 and 98.7% respectively.     

Flow dynamics in perforated plate liquid extraction columns

A linearized unsteady state flow model is developed for two counter-currently flowing liquids in an un-agitated perforated plate liquid–liquid column contactor. The model is based on the simultaneous solution of dynamic conservation equations and linearized hydrodynamic constitutive equations relating pressure drops and dispersed phase holdups to flow rates. Analytical expressions are obtained for the dynamic responses of inter-stage continuous and dispersed phase flow rates, inter-stage holdups, and level of the top interface to changes in the light liquid and heavy liquid inflow rates to the column. The system's dynamic behavior is vividly demonstrated through a set of typical frequency and transient response computations. Owing to the interaction between the dynamics associated with the flow of the two liquids, the frequency responses of the flow rates and holdups of the two phases are characterized by resonance peaks and non-minimum phase behavior.     

Removal of Cu2+ from Water Using Liquid-Liquid Microchannel Extraction

The very good extraction selectivity of Cu²⁺ from water was demonstrated with a new microchannel equipment, by employing di-(2-ethylhexyl)phosphoric acid (D2EHPA) as an extractant and kerosene as a solvent. The effects of different experimental parameters on the extraction efficiency E, the volumetric mass transfer coefficient K_La, and the entrainment were experimentally investigated. The results showed that the extraction efficiency increased with increasing temperature, extractant concentration, phase ratio (organic/aqueous), and pH. The total flow rate, phase ratio, and pH were found to have a great effect on the mass transfer, whereas the temperature and the extractant concentration showed little effect.     

正辛基-对叔丁基苯基亚砜萃取钯(Ⅱ)的动力学研究

采用恒界面池搅拌法测定了正辛基－对叔丁基苯基亚砜萃取钯（Ⅱ）的反应速率常数（kf)和反应的表观活化能（Ea),初步探讨了亚砜类萃取剂结构对其萃取性能的影响。     

C4馏分丁二烯萃取精馏塔的模拟和分析

采用PRO/Ⅱ流程模拟软件对C4馏分丁烯萃取精馏塔进行模拟计算,模拟计算说明,原为氧化脱氢丁二烯设计的丁烯萃取精馏塔,可改用于处理C4馏分。     

一缩二乙二醇催化脱水制取1,4一二氧六环的研究

研究了在对甲基苯磺酸作用下,一缩二乙二醇脱水制取1,4-二氧六环的工艺方法和操作条件。实验考察了催化剂种类,催化剂用量、反应温度、反应时间等因素对1,4-二氧六环收率的影响,用对甲基苯磺酸作催化剂,1,4-二氧六环收率达92%。采用萃取分离反应产物,确定了较理想的萃取剂,并考察了萃取剂用量对萃取率的影响。     

氯化血红素提取新工艺的研究

探讨了从新鲜猪血中提取氯化血红素的新工艺,利用红外光谱对产品进行了定性检验。以上海丽珠东风生物技术有限公司生产的氯化血红素为对照品,利用紫外光谱进行了定量测定,质量分数为对照品的1．03－1．07倍。此工艺简单易行,成本低,经济效益好。     

用超临界CO2流体从香兰草豆荚中萃取香兰素的研究

研究了用超临界CO2 流体技术从香兰豆荚中萃取香兰素的工艺条件 ,探索了萃取压力、温度、时间对萃取率的影响 ,结果表明 ,超临界CO2 萃取香兰素的工艺切实可行 ,最佳萃取条件是萃取压力为 35 0bar、温度为 4 5℃、时间为 14 0min ,在此萃取条件下每克香兰豆荚的香兰素萃取量为 2 0 .0 5mg ,萃取率为 98.5 %。     

Process optimisation in sunflower oil extraction by supercritical CO2

A continuous process for the extraction of sunflower oil using supercritical CO₂, featuring multiple extractors, one oil separator and three cascaded CO₂ recovery vessels operating at different pressures, was devised and studied. For every single equipment of the plant making up the process a mathematical model was built. Experimental tests—consisting in measurements of oil solubility in supercritical CO₂—were carried out in a laboratory-scale apparatus to characterise the behaviour of sunflower oil in the separation from the supercritical fluid. The mathematical model of the whole process was coded in the commercial gPROMS process modelling environment where both its simulation and optimisation—this latter assuming the overall oil production cost as the objective function—were carried out. The process- and economics-related results are discussed and compared with those obtained with traditional and cold-pressing extraction.