长链离子液体临界胶束浓度研究

采用毛细上升法测定[Cn MIm]Br(n=12,14,16)3种长链离子液体与十二烷基硫酸钠(传统阴离子表面活性剂)的表面张力,通过表面张力拐点得到临界胶束浓度。结果表明,长链离子液体与传统表面活性剂临界胶束浓度相当;在临界胶束浓度下,长链离子液体表面张力相差不大,且都略小于传统表面活性剂,则其表面活性优于传统阴离子表面活性剂。     

长链离子液体临界胶束浓度研究

采用毛细上升法测定[Cn MIm]Br(n=12,14,16)3种长链离子液体与十二烷基硫酸钠(传统阴离子表面活性剂)的表面张力,通过表面张力拐点得到临界胶束浓度。结果表明,长链离子液体与传统表面活性剂临界胶束浓度相当;在临界胶束浓度下,长链离子液体表面张力相差不大,且都略小于传统表面活性剂,则其表面活性优于传统阴离子表面活性剂。     

离子液体表面活性剂的合成与应用(Ⅵ)——离子液体表面活性剂的界面张力

离子液体表面活性剂在油/水界面吸附,降低界面张力。随着疏水烷基链长的增加,降低表面张力的能力增大。吡啶基表面活性剂比咪唑基表面活性剂具有更高的疏水性和降低界面张力能力。在高浓度无机盐存在下,离子液体表面活性剂降低界面张力的能力提高,界面张力可达10~(-2)mN/m,优于传统表面活性剂。     

“拉环法测定液体表面张力”实验讨论

在物理化学实验中,液体表面张力的测定是必修的实验之一,特别是表面张力仪法测定液体的表面张力。文章对＂拉环法测定液体表面张力＂这一实验的原理进行阐述分析。经过实验教学中的观察实践,指出了学生容易在液体表面张力值的确定上产生疑问。文中正是针对这个疑问,结合电压随时间的变化图和吊环所受液体表面张力示意图进行分析讨论,给出了详细的解释,为学生答疑解惑。     

离子液体型表面活性剂的研究进展

离子液体型表面活性剂是一种功能性离子液体,具有离子液体的特性,还具有双亲特性.简述了离子液体型表面活性剂的制备方法,在此基础上,重点综述了离子液体型表面活性剂的表面吸附、临界胶束浓度、表面张力等表面性能;同时介绍了离子液体型表面活性剂在微乳液聚合和酶催化反应中的应用,并对离子液体型表面活性剂的发展方向进行了展望.     

松香蒸馏过程中,脂液、松香表面张力的测定

一、液体的表面张力处在液体表面层的分子受液体内层邻近分子的引力要比从空气分子方面所受的引力大。因此,要使液体形状改变而表面增大时,必须消耗功。这个沿着表面本身并与表面平行、有一种力图使表面缩小的张力称为表面张力。其单位是尔格/平方厘米或达因/厘米。     

含胺功能基团离子液体表面活性剂的合成及性能

本文研究了三种含胺功能基团的离子液体表面活性剂的合成方法,并利用红外光谱仪和滴体积法对其官能团结构和水溶液表面张力进行表征.结果表明,表面活性剂在波数1338、1234、1465和3142cm-1处具有咪唑环的C-N、C-H特征吸收峰,具备离子液体的结构特征.表面张力等温曲线证实,随着碳链的增长,临界胶束浓度(CMC)...     

氯盐离子液体水溶液的物理化学性质

离子液体是一类新型表面活性剂,研究离子液体+水体系的物性具有重要的意义。为此,本文测定了不同浓度和温度下［Bemim］［Cl］（氯化-1-甲基-3-苄基咪唑）,［C_nmim］［Cl］（氯化-1-甲基-3-烷基咪唑, n=4,14,16）,［BeiQu］［Cl］（氯化-N-苄基异喹啉）,［C_miQu］［Cl］（氯化-N-烷基异喹啉, m=4,8）等氯盐离子液体水溶液的密度、动力黏度、表面张力等物化性质。氯盐离子液体水溶液密度的变化趋势为咪唑类>异喹啉类。离子液体水溶液的黏度随着温度的升高而减小,随着浓度的升高而升高。在等温条件下,阳离子取代基相同时,离子液体水溶液的表面张力的变化趋势为咪唑类<异喹啉类。     

常用临界胶束浓度的测定方法

1)表面张力法:表面张力测定法适合于离子表面活性剂和非离子表面活性剂cmc的测定,无机离子的存在也不影响测定结果。在表面活性剂浓度较低时,随着浓度的增加,溶液的表面张力急剧下降,当达到cmc后,表面张力的下降则很缓慢或停止。     

匀染剂O通过鉴定

匀染剂O是一种非离子表面活性剂,它在极稀薄的浓度下,可显著的降低水的表面张力和水与油、液体与固体间的界面张力,从而显示出优异的乳化渗透、净洗、分散、发泡和增溶等作用。它在水中溶解时不发生电离作用,在酸、碱、盐水溶液中稳定、可     

微波法离子液体介质中纳米TiO2光催化剂制备及催化活性

以钛酸丁酯为前驱物,在离子液体1-丁基-3-甲基咪唑六氟磷酸盐、水和无水乙醇组成的混合溶剂中,采用溶胶-凝胶法和微波干燥,制备了纳米TiO₂光催化剂,并用XRD、TG和IR对催化剂结构进行了表征。以甲基橙为模拟污染物,高压汞灯为光源,考察了离子液体用量、焙烧温度、微波功率和微波干燥时间等对TiO2光催化剂活性的影响。结果表明,在n（［Bmim］PF₆）∶钛酸丁酯）=3.0、焙烧温度550 ℃、微波干燥功率210 W和微波干燥时间20 min条件下,离子液体介质中用微波干燥所得的纳米TiO₂催化剂具有较高的光催化活性,90 min使甲基橙降解率达97.8%,表明离子液体的存在抑制了TiO₂由锐钛矿相向金红石相的转变,并起增大TiO₂比表面积及表面羟基含量的作用     

Experimental and modeling study for the removal of formic acid through bulk ionic liquid membrane using response surface methodology

Abstract

In this study, formic acid removal from its aqueous solutions through bulk ionic liquid membrane (BILM) was investigated. Tributyl phosphate (TBP) as a carrier in imidazolium-based ionic liquids was used. D-optimal design based on response surface methodology has been applied to investigate the effect of various operating factors. Initial formic acid concentration, TBP concentration, and NaOH concentration were selected as numerical factors, and ionic liquid type was chosen as a categorical factor. The model equations were obtained to determine BILM process behavior. The removal efficiencies, represented by the extraction and stripping efficiencies, were calculated from the experimental data. The highest removal efficiencies were determined at higher concentration values of TBP and NaOH. All ionic liquids studied in this study had good transport selectivity for the removal of formic acid. The design study showed that BILM is an effective method for the removal of formic acid from the water.     

离子液体-水体系循环使用对白松木质素提取的影响

使用氯代丁基咪唑盐离子液体的水溶液分离白松中的木质素。在[C₄min]Cl/H₂O质量比为6∶4,混合液与白松质量比为10∶1,提取温度150℃下,提取白松木质素。离子液体-水可多次循环用于提取白松木质素,溶剂体系循环使用对木屑失重率、木屑残渣综纤维素含量和离子液体木质素提取率均有影响。通过UV和FT-IR分析提取物的结构,并与磨木木素比较,证明提取物中有木质素的特征官能团。通过SEM分析观察提取木质素前后木屑表面的变化,发现提取后木屑表面出现了大量纹孔,纹孔膜消失。     

固载离子液体聚合物的制备及其二氧化碳吸附性能

分别采用溶液聚合法和表面引发反向原子转移自由基聚合法(ATRP),在硅胶表面接枝离子液体聚合物,并对其进行了FTIR、TG和SEM表征。研究了固载离子液体聚合物样品的CO2吸附性能和CO2/N2的选择性能,探讨了CO2在固载离子液体聚合物上的吸附热力学和动力学行为。结果表明:由ATRP法制备的固载离子液体聚合物,其接枝量远大于溶液聚合法;而溶液聚合法制备的样品具有较发达的孔结构,在273 K、0.1 MPa时,样品的CO2吸附量达4.54%(1.03 mmol/g);固载离子液体聚合物较空白硅胶具有更优的CO2/N2选择性,且循环使用性良好;CO2在固载离子液体聚合物上的吸附为物理吸附;与离子液体聚合物相比,CO2在固载离子液体聚合物中的扩散效率更高。     

离子液体中电沉积钴-银软磁薄膜

使用离子液体(EMIC)和乙二醇的混合液作为电解液,电沉积制备钴-银软磁薄膜。研究发现,乙二醇能够有效地解离离子液体,从而增加电解液中氯离子和钴配合物的浓度。增大电解液中乙二醇的体积,有利于加快钴的沉积速率,提高钴-银薄膜中钴的质量分数,从而提高钴-银薄膜的比饱和磁化强度。随着乙二醇的体积的增大,钴-银薄膜从颗粒状逐渐转变为枝晶状,矫顽力逐渐增大。     

Use of Ionic Liquid in Fabrication, Characterization, and Processing of Anodic Porous Alumina

Two different ionic liquids have been tested in the electrochemical fabrication of anodic porous alumina in an aqueous solution of oxalic acid. It was found that during galvanostatic anodization of the aluminum at a current density of 200 mA/cm², addition of 0.5% relative volume concentration of 1-butyl-3-methylimidazolium tetrafluoborate resulted in a three-fold increase of the growth rate, as compared to the bare acidic solution with the same acid concentration. This ionic liquid was also used successfully for an assessment of the wettability of the outer surface of the alumina, by means of liquid contact angle measurements. The results have been discussed and interpreted with the aid of atomic force microscopy. The observed wetting property allowed to use the ionic liquid for protection of the pores during a test removal of the oxide barrier layer.     

Effects of bmim[PF6] treatments with different concentrations on microbial activity of <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis>

To study the role of ionic liquid as a solvent in whole cell biocatalyst, it is necessary to probe the effects of ionic liquid treatments on microbial activity. In this paper, Saccharomyces cerevisiae was selected as a test bacterium to study the effects of bmim[PF6] ionic liquid in different concentration on yeast activity through determining the growth curve, sugar degradation curve, microbial activity, colonial morphology and cell morphology. The results revealed that the growth of yeast is inhibited strongly in low concentration ionic liquid, while the lethal effect is feeble in high concentration ionic liquid. This result was totally different from that of supercritical CO₂ treatment or high concentration benzene methanol treatment which would lead most yeast to death.     

Biocatalytic production of ricinoleic acid from castor oil: augmentation by ionic liquid

Abstract

In present study involving castor oil hydrolysis catalyzed by porcine pancreas lipase, organic solvent, and ionic liquid were applied to augment production of ricinoleic acid. Toluene was the best organic solvent (30.18% hydrolysis in 2?h). In presence of 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF₆]), an ionic liquid, the optimal conditions were, 0.12?g ionic liquid/g oil, 4?mg enzyme/g oil, 2?g buffer/g oil, pH of 8, and 2.5?h. Under this condition, ricinoleic acid recovery was 43.41 and 52% at 25?°C and 35?°C, respectively. Organic solvent concentration, enzyme concentration, buffer concentration and time had significant impacts on lipase catalyzed hydrolysis in the presence of organic liquid; whereas, pH and speed remained insignificant. In hydrolysis involving ionic liquid, time had most important effect on ricinoleic acid production. Interaction between enzyme and buffer concentration was most significant. Interactions of ionic liquid concentration with all other variables were also significant besides buffer concentration–time interaction.     

烯丙基哌啶类离子液体的合成与物化性能研究

以哌啶、溴代正丁烷和烯丙基溴为原料,采用两步法合成出了烯丙基哌啶类离子液体,并用红外光谱（IR）对产物进行了分析表征。同时考察了其在不同溶剂中的溶解性能及导电性能。结果表明,离子液体在水、乙醇、乙酸、丙酮中可以较好的溶解,而在乙醚、正己烷中基本不溶;离子液体的电导率随浓度的增大和温度的升高而增大。     

室温离子液体[BMIm]PF_6中纳米银的制备及结构表征

在微波条件下合成了1-丁基-3-甲基咪唑六氟磷酸盐([BMIm]PF6)离子液体,用红外光谱对其结构进行了表征。用该离子液体作为反应介质,采用硼氢化钠为还原剂制备了金属银纳米微粒,用X射线衍射、扫描电子显微镜、傅立叶红外光谱和热分析对纳米银的结构和形貌进行了表征。结果表明,所制备的纳米银具有立方相结构,粒径约为10 nm;离子液体不但作为反应的溶剂而且还作为修饰剂,包覆在银纳米微粒的表面,从而阻止了银纳米微粒的团聚。