溶剂萃取法从褐藻浸提液中分离提取褐藻糖胶

用溶剂萃取法分离提取了实际海藻浸提液中的褐藻糖胶. 考察了接触时间、溶剂加入量及萃取剂浓度等对萃取的影响，并与从多糖配制液中的萃取情况进行比较. 考察了无机盐水溶液反萃褐藻糖胶的性能及在溶剂中加入TOA(三正辛胺)对萃取和反萃的影响，结果表明，季铵盐从实际鼠尾藻浸提液中萃取褐藻糖胶受溶剂加入量的影响很大，溶剂加入量越大，萃取率越低；而萃取时间对萃取的影响不大. 海带浸提液的萃取优于鼠尾藻浸提液，而超声破碎法有利于萃取. TOA的加入既有利于褐藻糖胶的萃取也有利于无机盐水溶液反萃褐藻糖胶. 采用溶剂萃取法制备的固体褐藻糖胶的纯度优于乙醇分步沉淀法制备的固体褐藻糖胶的纯度.     

海带中褐藻糖胶的酸提法研究

采用酸提法从海带中提取褐藻糖胶,分别采用MgCl、乙醇分级沉淀法进行纯化.主要探讨了提取时间、温度、pH等因素对提取率的影响.结果表明,在提取温度70 ℃,pH 2.5,70%乙醇浓度,提取3 h,提取率为7.3%.乙醇分级沉淀法提取率高于MgCl法.     

褐藻糖胶中硫酸根质量分数的测定方法

介绍了褐藻糖胶中硫酸根质量分数的测定方法。褐藻糖胶中硫酸根质量分数的测定方法主要有硫酸钡比浊法、盐酸水解硫酸钡重量法、分光光度法和离子色谱法,综述了4种方法的原理、简单的操作过程、影响因素以及其优缺点等。     

褐藻糖胶吸湿、保湿性能的研究

以甘油和山梨醇为参照物,分别在两种相对湿度下考察了褐藻糖胶粗品和较纯品的吸湿、保湿率以及随时间的变化情况,并且探讨了保湿剂的选择原则.结果表明,褐藻糖胶具有一定程度的吸湿性和较持久的保湿性,尤其在较干燥环境下,保湿性优于甘油和山梨醇.因此,其作为保湿剂有着一定的应用前景.     

褐藻糖胶吸湿、保湿性能的研究

以甘油和山梨醇为参照物,分别在两种相对湿度下考察了褐藻糖胶粗品和较纯品的吸湿、保湿率以及随时间的变化情况,并且探讨了保湿剂的选择原则.结果表明,褐藻糖胶具有一定程度的吸湿性和较持久的保湿性,尤其在较干燥环境下,保湿性优于甘油和山梨醇.因此,其作为保湿剂有着一定的应用前景.     

反胶团萃取蛋白质设备

综述了反胶团萃取蛋白质设备的研究进展.按设备形式和操作方式的不同将反胶团萃取设备分为膜萃取器、离心萃取器、混合澄清槽和微分萃取器,指出了各自的优缺点,强调了萃取设备的基础研究和开发新型反胶团萃取设备的必要性.     

混合离子交换树脂纯化褐藻糖胶的工艺研究

研究了混合离子交换树脂(按001×7强酸性苯乙烯系阳离子交换树脂和201×7强碱性阴离子交换树脂质量比1:1混合)对褐藻糖胶粗品的脱盐纯化工艺,同时考察了三氯乙酸法对褐藻糖胶溶液的脱蛋白效果。通过单因素实验,对影响混合离子交换树脂脱盐效果的料液比及脱盐时间进行了分析;通过研究溶液中蛋白质及总糖含量的变化规律,得出三氯乙酸法脱蛋白实验方法中三氯乙酸试剂的最佳添加量。结果表明:当料液体积与混合离子交换树脂质量的比例为1:3,脱盐时间为60分钟时脱盐效果最佳,脱盐率可达65.12%。三氯乙酸法脱蛋白实验方法中三氯乙酸试剂的最佳添加量为13%(V/V),脱蛋白率为85.17%。研究所确定的纯化工艺可以作为纯化分离褐藻糖胶的较佳工艺加以推广。     

反胶团萃取蛋白质技术

反胶团萃取是近年发展起来的分离和纯化生化物质的新方法。本文介绍反胶团萃取蛋白质技术的原理，概述其热力学和动力学研究进展，评述其工业应用前景。     

聚合物胶团萃取与聚合物反胶团萃取

介绍了从两亲聚合物及聚合物胶团的形成、聚合物胶团的加溶作用、聚合物胶团加溶理论等方面对聚合物胶团萃取的研究进展做了综述。同时,介绍了作者提出并研究的聚合物反胶团萃取的特性及影响因素。     

反胶团萃取蛋白质特性的研究

实验将一种阴离子表面活性剂（AOT）和一种阳离子表面活性剂（Aliquat336）分别溶于异辛烷（isooctane）中，构成了两种不同的反胶团体系．通过用两种不同的反胶团溶液萃取六种蛋白质的实验，研究了水相pH值及离子强度对反胶团体系中水含量Wo和蛋白质萃取率影响的规律．实验发现不论哪种反胶团体系，水相pH值对Wo的影响都不大，但pH值却对蛋白质萃取率有很大的影响，对AOT反胶团体系而言，随着pH值的降低，蛋白质的萃取率升高；对Aliquat336反胶团体系而言，随着水相pH值的降低，蛋白质的萃取率下降．随着离子强度的增大，AOT反胶团体系的水含量大幅度地降低；而对Aliquat336体系水含量的影响很小，但水相离子强度对蛋白质萃取率的影响是相同的，随着离子强度的增大，两种体系对蛋白质的萃取率均下降。     

Extraction of Pb2+ with p-tert-butylcalix [4]-, [5]-, [6]Arene Carboxylic Acid Ligands and their Monomeric Counterpart: A Thermodynamic Approach

Studies on extraction equilibrium constants at different temperatures and thermodynamic parameters of solvent extraction of Pb²⁺ ion with carboxylic acid derivatives of different ring size calixarenes and structure related monomeric compound have been carried out. The extraction equilibrium constants corresponding to calix[n]arene (n?=?4, 5, 6) derivatives decrease in the order [5]arene > [6]arene > [4]arene. In all cases, the complexation process is primarily enthalpy driven. The favorable enthalpic contribution for extraction of Pb²⁺ is in the order hexamer ≈ monomer > tetramer > pentamer. However, the unfavorable entropic loss follows the order: monomer > hexamer > tetramer > pentamer. Overall stability of the host-guest complex is the function of entropy-enthalpy compensation and the free energy of complexation is minimum for the pentamer, followed by tetramer ≈ hexamer and monomer. Although the carboxylic acid derivative of calix[4]arene is more preorganized than the calix[5]arene derivative, extraction of Pb²⁺ ion with the tetramer passes through greater entropic loss than that with the pentamer and the degree of preorganization of calix[4]arene derivative is far from perfect for the complexation and extraction of Pb²⁺ ion. As compared to tetrameric and hexameric counterparts, the structural features of the carboxylic acid derivative of calix[5]arene prior to complexation contribute much to interact with the Pb²⁺ ion and form a thermodynamically stable complex. Supplementary materials are available for this article. Go to the publisher's online edition of Solvent Extraction and Ion Exchange to view the supplemental file.     

Extraction of Radioactive Cs and Sr from Nitric Acid Solutions with 25,27-Bis(1-octyloxy)calix[4]-26,28-Crown-6 and Dicyclohexyl-18-Crown-6: Effect of Nature of the Organic Solvent

Extraction of microamounts of radioactive cesium and strontium by 25,27-bis(1-octyloxy)calix[4]-26,28-crown-6 (DOC[4]C6) and dicyclohexyl-18-crown-6 (DCH18C6) from nitric acidic solutions into alcohols, ketones and some other solvents was studied. We concentrated on collecting detailed data possibly useful for subsequent evaluations of appropriate schemes and mechanisms. Although not testing in fullness the system with DOC[4]C6 and DCH18C6 in 1-octanol, we present some evidence of its suitability such as fast kinetics, chemical and radiation stability, and invariance of parameters (process stability) after several times repeated batch extraction-strip cycles. Some peculiarities of a possible mechanism of extraction in these systems are reported.