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糠醛水溶液的液-液萃取分离 总被引:4,自引:0,他引:4
糠醛是重要的化工溶剂和中间体,传统生产过程流程复杂[1],能耗高。近年已提出用不同溶剂萃取分离糠醛和水[2]。本文在前文基础上[3]选择醋酸丁酯为萃取剂测定糖醛-水-醋酸丁酯体系的LLE数据,由二组二元体系和三元体系液液平衡数据确定UNIQUAC模型中三对模型参数,并采用UNIQUAC模型模拟计算糖醛水溶液萃取分离结果,以便为错流和逆流萃取试验提供依据。1 实验部分糠醛水溶液和醋酸丁酯加入液液平衡釜[4],磁力搅拌器搅拌30分钟,待温度稳定后,静置40分钟,取上相和下相分析。平衡釜采用CS501型超级恒温水浴控温,平衡结果由SP-6800… 相似文献
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双水相萃取法富集分离银杏叶浸取液的探讨 总被引:17,自引:0,他引:17
以银杏叶提取液制成的药物 ,用于对心血管、脑血管、动脉硬化、高血压等疾病的治疗 ,有其它药物不能达到的特殊疗效[1~4] 。另外 ,银杏叶制剂长期服用没有毒副作用 ,这是同类西药无法达到的。银杏叶制品还可用于生物农药、保健食品、化妆品等方面。从银杏叶中取提主要药用成分黄酮类化合物是研究开发银杏叶应用的关键 ,包括银杏叶黄酮化合物的浸取和浸出液的富集分离两个步骤以及①有机溶剂萃取法 ;②双水相萃取法 ;③离子吸附法等富集分离黄酮类化合物的方法[5 ,6] 。近 2 0年来 ,溶剂萃取技术与其它技术相结合 ,产生了一系列新的分离技术… 相似文献
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天然产物作为一种绿色低毒、来源广泛、功能位点丰富的单体,已被广泛应用于色谱固定相的研制与开发。该文以天然可再生资源腰果酚为配体,通过一步法开环反应将其接枝到由γ-缩水甘油醚氧丙基三甲氧基硅烷(KH-560)修饰的硅胶上,制备得到腰果酚键合硅胶固定相。利用傅里叶红外光谱、元素分析、热失重分析和N_(2)吸附脱附实验对固定相进行表征,结果表明成功制备了腰果酚键合硅胶色谱固定相。采用Tanaka实验试剂、烷基苯、多环芳香烃、苯酚类化合物和芳香族位置异构体为探针评价其分离性能和保留机制,并与C_(18)柱进行对比。研究发现,腰果酚键合固定相除疏水作用外,还具有π-π和氢键作用。基于上述保留作用,腰果酚键合硅胶固定相对测试探针表现出良好的分离性能。重复进样10次,各探针保留时间的RSD为0.052%~0.079%,峰面积的RSD为0.104%~0.847%,峰高的RSD为0.081%~0.272%,表明该色谱柱具有良好的重复性和稳定性。此外,腰果酚键合硅胶色谱柱对中药喜树果和吴茱萸果的粗提物具有良好的分离性能,验证了其在实际样品分析中的巨大潜力。将天然产物腰果酚用于色谱固定相的制备,为分离纯化喜树碱和吴茱萸提供了新的方法,同时拓展了腰果酚在色谱分离材料方面的应用。 相似文献
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重力场流分离作为最简单的一种场流分离技术,常用于分离微米级颗粒。选择两种不同粒径(20 μ m和6 μ m)的聚苯乙烯(PS)颗粒作为样品,通过改变载液中叠氮化钠浓度、混合表面活性剂的比例及载液流速,利用自行设计生产的重力场流分离(gravitational flow field-flow fractionation, GrFFF)仪器,对颗粒混合样品进行分离,得到了相关谱图与数据,考察了这3种因素对分离效果(保留比(R)、塔板高度(H))的影响。结果表明:20 μ m PS颗粒的R值均大于6 μ m PS颗粒的R值,H值均小于6 μ m颗粒的H值;PS颗粒的R值与H值均随着载液中叠氮化钠浓度的增加而增加;但随着载液流速的增加,R值增加,H值减小。该研究为GrFFF系统的开发及应用提供了重要的参考价值。 相似文献
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In this work, the blends of epoxy (EP) and polycaprolactone (PCL) with a bio-based curing agent, viz. cashew nut shell liquid (CNSL) were studied for their dual-responsive shape memory and self-healing behaviors. The suitable EP/CNSL weight ratio was observed at 70/30. The increase of PCL content up to 20 wt% in EP-CNSL matrix significantly enhanced the shape memory response to both thermal and chemical stimuli. All specimens showed 100% thermo-responsive shape recovery and the recovery time decreased with increasing PCL content. In the case of chemo-responsive shape memory, the immersion times spent for 100% shape recovery in water and methanol substantially decreased when PCL was added. Moreover, after thermal treatment, the EP-CNSL matrix with 20 wt% PCL showed significant self-healing ability with high tensile strength recovery at 93.70%. The EP-CNSL/PCL copolymer could be a promising alternative bio-related smart material for various applications such as dual-activated sensors and coatings with self-healing ability. 相似文献
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H. P. Bhunia R. N. Jana A. Basak S. Lenka G. B. Nando 《Journal of polymer science. Part A, Polymer chemistry》1998,36(3):391-400
A novel thermoplastic polyurethane was prepared from cardanol, a renewable resource and a waste of the cashew industry. Cardanol was recovered from cashew nut shell liquid (CNSL) by double vacuum distillation. It was characterized by CHN analysis and IR, 1H-NMR, and 13C-NMR spectroscopy techniques. Cardanol is a meta-substituted long chain phenol. The long aliphatic chain unit substituent was found to be a monoene. The monomer, 4-[(4-hydroxy-2-pentadecenylphenyl)diazenyl]phenol was prepared from cardanol. It was a dihydroxy compound as characterized by CHN analyzer, UV, and 1H-NMR spectroscopy. The polyurethane was synthesized from this dihydroxy compound by the treatment with 4,4′-diphenylmethane diisocyanate (MDI) in dimethylformamide (DMF) solvent at 80–90°C under nitrogen atmosphere. The polymer was characterized by 1H-NMR, FTIR, and UV spectroscopy. The elemental analysis was done for determining the percentage content of C, H, and N, and the intrinsic viscosity [η] of polymer showed 1.85 dL/gm. Thermogravimetric investigations (TGA) of the cardanol, the dihydroxy compound, and the polyurethane were performed to study their decomposition. The semicrystalline nature of the PU was confirmed by differential scanning calorimetry (DSC) and dynamic mechanical thermal analyzer (DMTA). The wide-angle X-ray diffraction (WAXS) study of PU shew a broad amorphous halo indicative of absence of crystallinity in the polymer, which has been explained as due to strong hydrogen bonding in the hard phase. PU may possibly be useful as a telecommunication and as a nonlinear optical material. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36 : 391–400, 1998 相似文献
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Samir M. Osman Ahmed M. Abdel‐Megied Mohammed H. Zain Eldain Simimole Haleema Chithra Gopinath Sarojini Amma Sumalekshmy Hassan Y. Aboul‐Enein 《Biomedical chromatography : BMC》2019,33(11)
The commercial value of cashew nut shell liquid (CNSL) has become a cornerstone of the agrowaste industry. It is the by‐product of the cashew industry and has an 1/8 inch thickness of soft honeycomb structure. CNSL contains phenolic lipids with aliphatic chains such as anacardic acid, cardanol, cardol and methyl cardol, and their derivatives. The developed GC–MS method is rapid, accurate and selective using a selected derivatizing reagent, namely N‐methyl‐N‐(trimethylsilyl)‐trifluoroacetamide that was previously diluted 1:1% with anhydrous pyridine. The proposed GC–MS method was applied for the analysis of different CNSL samples. The results showed that all classes of CNSL compounds were detected. The four alkyl phenols were detected with their different alkyl sidechains without any interference. This method is also specified for the detection of fatty acids of saturated and unsaturated chains. Silylation did not cause any alteration in the chemical structure of CNSL compounds regardless of esterification action. Silylation is considered a safe derivatizing agent compatible with GC chromatography and specific for all volatile and nonvolatile polar and nonpolar CNSL compounds that could be detected in CNSL samples. 相似文献
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Elisa Uliassi Andressa Souza de Oliveira Luciana de Camargo Nascente Luiz Antonio Soares Romeiro Maria Laura Bolognesi 《Molecules (Basel, Switzerland)》2021,26(18)
Alzheimer’s disease (AD) is a complex neurodegenerative disorder with a multifaceted pathogenesis. This fact has long halted the development of effective anti-AD drugs. Recently, a therapeutic strategy based on the exploitation of Brazilian biodiversity was set with the aim of discovering new disease-modifying and safe drugs for AD. In this review, we will illustrate our efforts in developing new molecules derived from Brazilian cashew nut shell liquid (CNSL), a natural oil and a byproduct of cashew nut food processing, with a high content of phenolic lipids. The rational modification of their structures has emerged as a successful medicinal chemistry approach to the development of novel anti-AD lead candidates. The biological profile of the newly developed CNSL derivatives towards validated AD targets will be discussed together with the role of these molecular targets in the context of AD pathogenesis. 相似文献
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A.R.R MenonA.I Aigbodion C.K.S Pillai N.M MathewS.S Bhagawan 《European Polymer Journal》2002,38(1):163-168
Natural rubber (NR) has been modified with 5-15 phr each of cashewnut shell liquid (CNSL) and cashewnut shell liquid-formaldehyde (CNSLF) resin with a view to studying the processability characteristics of the mixes and physicomechanical properties of their vulcanizates. The plasticizing effect of these additives in NR was shown by the reduction in melt viscosity and power consumption during mixing in a Brabender Plasticorder compared to that of unmodified NR. Despite the reduction in chemical crosslink density, the vulcanizates containing 15 phr of CNSL and 5-10 phr of CNSLF showed higher tensile and tear strengths and elongation at break. The higher values of activation energy for thermal decomposition of the vulcanizates containing 15 phr each of CNSL (301 kJ/mol) and CNSLF (372 kJ/mol) than that of the unmodified NR vulcanizate (177 kJ/mol) indicate improvement in thermal stability of NR vulcanizates in presence of the modifiers. 相似文献
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Tejas S. Gandhi Mayank R. Patel Bharatkumar Z. Dholakiya 《Research on Chemical Intermediates》2014,40(3):1223-1232
Cashew nut shell liquid (CNSL) is a natural aromatic organic oil consisting of phenolic compounds with interesting structures. Extraction of CNSL was performed in a Soxhlet apparatus. The major (90 %) component of CNSL is anacardic acid, which is easily decarboxylated to cardanol (10 %) by use of conventional methods. In this paper we describe a three-step synthesis of Mannich polyols for rigid foams. The first step is synthesis of N-(2-hydroxyethyl)-1,3-oxazolidine (the Mannich precursor) by condensation of paraformaldehyde and diethanolamine. The second step involves synthesis of the Mannich base phenolic ring of cardanol by reaction with N-(2-hydroxyethyl)-1,3-oxazolidine. The third step is alkoxylation. The synthesized polyols were characterized by FTIR and 1H NMR spectroscopy and thin-layer chromatography. 相似文献
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《Physics and Chemistry of Liquids》2012,50(5):652-660
The desulphurised experiment of an organic physical solvent of dimethyl sulphoxide (DMSO) mixed with a relatively small amount of Mn(II) catalyst, based on the novel desulphurisation technology using the organic solvent as absorbent, is studied. Results indicate that Mn(II) plays a significant catalytic role. Compared with pure physical solvent of DMSO, the purification efficiency of SO2 with a small amount of catalyst has been much improved, and its absorption and reaction mechanism by liquid absorption with catalysed reaction are discussed. 相似文献
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离子液体双水相萃取分离苋菜红的研究 总被引:12,自引:0,他引:12
建立了由亲水性离子液体四氟硼酸1-丁基-3-甲基咪唑([Bmim]BF4)和NaH2PO4形成的双水相体系萃取分离苋菜红的新方法.研究了盐的浓度、离子液体浓度、溶液酸度、其它共存物质对苋菜红萃取率的影响.结果表明,NaH2PO4加入量在2~2.5 g,离子液量在1.0~2.0 mL,苋菜红溶液量在1.5 mL,溶液酸度在pH 4~6范围,离子液体双水相体系对苋菜红有较高的萃取率(E%>90).用加入无机离子、不同类型表面活性剂和吸收光谱探讨了离子液体与苋菜红之间的作用. 相似文献