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乳状液膜法分离水中汞的研究 总被引:3,自引:0,他引:3
报道了用乳状液膜法分离汞的研究。确定了最佳分离条件;流动载体TBP(磷酸三丁酯)和表面活性剂Span80的浓度均9%,内相溶液NaOH和外相溶液HCl的浓度分别为0.4mol/L和0.02mol/L,制乳时间和混合时间分别为10min和5min,乳水比和油内比分别为0.5和0.8。 相似文献
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液膜富集分光光度法测定水中痕量铬(Ⅵ) 总被引:5,自引:0,他引:5
本文研究了分离,富集Cr(Ⅵ)的最佳液膜组成和实验条件,确立了兰113B-TOA-煤油-液体石蜡-NaOH液膜体系。用本法富集,测定工业废水中的Cr(Ⅵ),富集倍数达75,相对标准偏差为1.1%,回收率99%以上。 相似文献
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乳状液膜法提取L-谷氨酸的研究徐占林(四平师范学院化学系四平136000)严忠张河哲(东北师范大学化学系长春130024)关键词L-谷氨酸乳状液膜载体萃取中图分类号O623.736氨基酸作为重要的生化产品,广泛应用于食品、饲料、医药、化工等许多领域,... 相似文献
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二(2,4,4—三甲基戊基)单硫代膦酸—上胺205—正庚烷乳状液膜萃取分离… 总被引:3,自引:0,他引:3
本文研究了外水相pH值,流动载体浓度,表面活性剂浓度,内相解析酸浓度,水乳比,油内比等因素对二(2,4-4-三甲基戊基)单硫代膦酸-上胺205-正庚烷乳状液膜迁移Sc的影响。在一定条件下,Sc可以快速而完全地迁移,有可能实现Sc与Fe,Lu的分离。 相似文献
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十二烷基苯磺酰胺喹啉作载体的液膜法提取水中铅的研究 总被引:6,自引:0,他引:6
研究了十二烷基苯磺酰胺喹啉萃取铅(Ⅱ)的行为。研究表明,此种萃取剂在一定的条件下,能有效萃取铅(Ⅱ),并采用斜率法探讨了对铅(Ⅱ)的萃取机理。在此基础上,研究了该萃取剂作为载体的乳状液膜对铅的提取。 相似文献
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乳状液膜法制备硫氧化物超细X射线发光粉 总被引:2,自引:0,他引:2
采用乳状液膜法制备了颗粒均匀的Gd-Tb草酸盐微粒,将草酸盐粒子放在硫气气氛下焙烧后得到Gd2O2S:Tb超细X射线发光粉。通过X射线衍射(XRD)、扫描电子显微镜(SEM)、红外(IR)光谱、光致发光(PL)光谱和X射线激发发光光谱(XEL)对微晶进行了表征。结果表明,900℃下焙烧后的粒子显示了单一的六角形Gd2O2S晶相,与传统固相法相比,有效降低了焙烧温度。根据谢乐公式,估算一次粒径为29nm,初级粒子尺寸较小,这在一定程度上可以提高成像系统的空间分辨率。从SEM照片来看,粒子显示了一定的团聚性,但团聚尺寸<5μm,为超细X射线发光粉。同时,在254nm紫外光和X射线激发下,Gd2O2S:Tb发光粉都显示出Tb^3 的特征发射峰,并且通过分析红外光谱对样品发光性能的影响作了详细的讨论。 相似文献
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Concentration of amino acids by a liquid emulsion membrane with a cationic extractant 总被引:5,自引:0,他引:5
The concentration of
-phenylalanine in a liquid emulsion membrane system was studied using a cation complexing agent, di-2-ethylhexyl phosphoric acid (D2EHPA), as a carrier. The membrane formulation, the pH in the internal phase of the acid concentration in the external phase were optimized with respect to concentration performance and membrane stability. It was found that a liquid emulsion membrane obtained by demulsification of the emulsion by an electrostatic coalescer could be reused. Based on the laboratory tests, a continuous multistage process for the concentration of amino acids was proposed (with the development of a commercial process in mind) and its technical feasibility was discussed. 相似文献
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Anil Kumar Parmjit Singh Panesar 《Journal of Dispersion Science and Technology》2018,39(10):1510-1517
A new stable green emulsion liquid membrane (GELM) was formulated by selecting the environmentally benign vegetable oils. The rice bran oil (RBO) based GELM has shown better stability in comparison to that obtained from other oils. GELM was prepared using 10?mL RBO, 0.25 [M] NaOH concentration, 2 (v/v, %) surfactant concentration, 0.4 (v/v) phase ratio, 2000?rpm emulsification speed, and 20?min emulsification time. Under these optimum conditions, GELM has been found to be stable for 120?±?2?min (no significant phase change) and has shown complete phase separation after 4 hours. Therefore, RBO as a green solvent has high potential to be applied in several ELM process applications. 相似文献
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The extraction of chromium (VI) ions from acidic solutions containing various metal ions by emulsion liquid membrane (ELM) was studied. Liquid membrane consists of a diluent, a surfactant, and an extractant. 0.5 M ammonium carbonate solution was used as stripping solution. Effects of acid concentration in feed solution, type and concentration of stripping solution, mixing speed, surfactant concentration, phase ratio and the influence of membrane characteristics were studied and optimum conditions were determined. Under the optimum conditions, extraction of chromium (VI) was tested and it was possible to selectively extract 99% of chromium from the acidic feed solution. This study also examined the effect of extractant concentration and acid type in the feed solution on the extraction of Cr (VI) ions and almost all of Cr (VI) from the acidic feed solution containing 500 mg/L from each of Co (II), Ni (II), Cd (II), Zn (II), and Cu (II) ions, and 100–500 mg/L Cr (VI) was extracted within 5–10 min. 相似文献
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A new redox-driven type of emulsion liquid membrane separation is described. Milligram amounts of copper(II) in 0.2 M hydrochloric acid were reduced to copper(I) in the presence of ascorbic acid (1 M≡1 mol l−1). The copper solution was emulsified with a (1+4) mixture of toluene and n-heptane using Span-80 (sorbitan monooleate) as an emusifier. The resulting water-in-oil emulsion was dispersed in 0.2 M hydrochloric acid containing hydrogen peroxide and neocuproine (2,9-dimethyl-1,10-phenanthroline) by stirring for 10 min. The copper in the internal aqueous phase was selectively transported to the external one, leaving other heavy metals (e.g., Mn, Co, Ni, Cd and Pb) in the internal aqueous phase. After collecting the dispersed emulsion globules, they were demulsified by heating and the metals in the segregated aqueous phase were determined by graphite-furnace atomic absorption spectrometry (GFAAS). The selective transport of copper offered the multielement separation of trace heavy metals from a copper matrix, allowing the GFAAS determination of impurities at the 0.01% level in copper metal. 相似文献
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A general physical model of a typical batch extraction system employing an emulsion liquid membrane process for the extraction of silver has been developed. The model takes into account the extraction reaction between the silver ion and the carrier molecules at the external interface, the diffusion of the complex in the membrane phase, the stripping reaction at the internal interface and the reaction of silver ion with the reagent, HCL, in the internal phase to yield silver chloride incapable of permeating through the membrane phase. In addition, the leakage of the internal aqueous phase to the external aqueous phase due to membrane breakage has been incorporated in this model. The batch extraction of silver using D2EHPA as a carrier has been carried out under various experimental conditions. The experimental data can be well explained by the present model. 相似文献
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The aims of this study are to form a liquid membrane suitable for the extraction of strontium ions from aqueous solutions and to determine the factors influencing the stability of the membrane, the extraction efficiency and the rate of transport. The suggested membrane is composed of kerosene, Span 80 and D2EHPA. It has been observed that the extraction efficiency and the rate of transport increase with increasing ratio of emulsion to outer phase volume, stirring rate and D2EHPA concentration and decreasing pH of the inner phase. As the strontium ion concentration in the outer phase increases, the transport rate increases but the separation efficiency decreases. The maximum separation efficiency achieved in the experiments was 92%. 相似文献
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Lu Liu Qingsheng Wu Yaping Ding Huajie Liu Baoquan Zhang 《Colloids and surfaces. A, Physicochemical and engineering aspects》2004,240(1-3):135-139
A new synthetic method of HgSe quantum dots has been investigated through template controlling with emulsion liquid membrane system. The membrane system consists of kerosene as solvent, span80 as surfactant, N7301 as carrier, and HgCl2 solution as internal-aqueous phase containing template of different concentrations, and uses gas–liquid transport on interface of external phase. Its optimum condition is as follows, kerosene:span80:N7301 = 74:6:20, Roi=1:1. While using inorganic KI as the template and adjusting HgCl2 concentrations (keeping KI/HgCl2 = 10), transmission electron microscope shows that HgSe quantum dots of different sizes can be obtained respectively, X-ray diffraction (XRD) reveals that the products have a cubic structure. The research has shown that quantum confinement effect of these HgSe quantum dots (2–3 nm) have inverted band structure (HgSe bulk) increase their effective bandgap giving rise to infrared (IR) luminescence. Its forming process is also inferred. 相似文献