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1.
研究了云南沱茶在不同浓度、温度、pH条件下, 自水溶液中吸附Ce(Ⅳ) 离子的特性, 并分别讨论了阴离子表面活性剂十二烷基硫酸钠(SDS), 阳离子表面活性剂氯代十六烷基吡啶(CPC) 和非离子表面活性剂聚乙二醇辛基苯基醚(OP) 对沱茶吸附Ce(Ⅳ) 离子的影响, 结果表明, 在一定条件下, 沱茶对铈(Ⅳ) 的吸附量可达7.95 mg*g-1, 吸附规律符合Langmuir等温方程, 计算了吸附热, 对沱茶吸附Ce(Ⅳ) 离子的机理进行了讨论.  相似文献   

2.
赵振国  顾惕人 《化学学报》1987,45(7):645-650
测定了15℃和30℃时炭黑自水和环己烷中吸附非离子型表面活性剂TritonX-100和Triton X-305的等温线;计算了吸附过程的标准热力学函数;测定了石墨/水/环己烷和石墨/水/空气的接触角与表面活性剂浓度的关系, 分析所得结果,可得结论:在炭黑/水或石墨/水界面上,Triton型表面活性分子形成单分子吸附层,分子以憎水的iso-C8H17C6H4基团附着在表面,而以亲水的聚氧乙烯链伸入水相的方式取向;在炭黑/环已烷或石墨/环己烷界面上,分子是通过聚氧乙烯链吸附到表面上的,当浓度增加时分子在表面可能通过聚氧乙烯链间的相互作用而发生聚集,即可能形成表面反式胶团。  相似文献   

3.
人血白蛋白制品中超痕量铝的测定   总被引:1,自引:0,他引:1  
建立了浊点萃取石墨炉原子吸收光谱法测定人血白蛋白样品中超痕量铝的新方法。探讨了溶液酸度、络合剂的种类及浓度、非离子表面活性剂的浓度、平衡时间及温度等因素对浊点萃取过程的影响。以1-(2-吡啶偶氮)-2-萘酚为络合剂,Triton X-114为非离子表面活性剂,浊点萃取分离富集10mL样品溶液,Al(Ⅲ)的富集倍数为34.8,在最佳工作条件下,铝的检出限为0.06μg/L;样品测定的相对标准偏差(n=7)为3.6%,加标回收率95.6%~98.4%。方法适合人血白蛋白样品中超痕量铝的分析测定。  相似文献   

4.
非离子表面活性剂浊点的研究进展   总被引:16,自引:0,他引:16  
莫小刚  刘尚营 《化学通报》2001,64(8):483-487
综述了非离子表面活性剂浊点的理论模型,介绍了非离子表面活性剂的浓度与外加无机电解质、极性有机物,表面活性剂、聚合物对浊点的影响规律和机理,以及在常压下浊点高于100℃时非离子表面活性剂的浊点估测方法。  相似文献   

5.
通过阴阳离子表面活性剂复配,在实际油水体系中获得了超低界面张力.通过在阴离子表面活性剂分子结构中加入乙氧基(EO)链段,以及采用阴阳离子加非离子型表面活性剂的三组分策略,有效解决了混合表面活性剂在水溶液中溶解度问题.进而研究了阳离子表面活性剂结构、非离子表面活性剂结构、三者组分配比、表面活性剂总浓度等因素对油水界面张力的影响,从而在胜利油田多个实际油水体系中获得了较大比例范围和较低浓度区域的油水超低界面张力,部分体系甚至达到了10-4 mN·m-1.由于阴阳离子表面活性剂间强烈的静电吸引作用,相关体系具有很好的抗吸附能力.经过石英砂48 h吸附后,体系仍然具有很好的超低界面张力.  相似文献   

6.
指示离子方波伏安法测定阳离子表面活性剂   总被引:1,自引:0,他引:1  
在非电活性的阳离子表面活性剂十二烷基二甲基苄基氯化铵(1227)中加入镉(Ⅱ),1227浓度对镉(Ⅱ)峰电流明显影响,镉(Ⅱ)作为指示离子,可测定微量阳离子表面活性剂的浓度。影响机理为配离子CdCl+和1227的阳离子(R+)都在阴极上吸附,CdCl+吸附使峰电流增大,R+吸附使峰电流减小。CdCl+吸附快,R+吸附慢。利用Oring 7.0拟合出1227存在下镉(Ⅱ)的还原峰电流数学模型。通过Origin 7.0非线性拟合出了CdCl+与R+的吸附常数和促进因子,对复杂吸附过程峰电流可进行定量计算。该方法为相对标准偏差(n=5)为2.2%,加标回收率为96.8%。  相似文献   

7.
非离子表面活性剂的加溶作用有助于正负离子表面活性剂的溶解,在恰当比例时,能基本保持其表面活性;正负离子表面活性剂与非离子表面活性剂之间的相互作用很弱,容易形成接近“理想”的混合胶团;恒定非离子表面活性剂浓度时,随正负离子表面活性剂浓度增加,溶液的浊点也增加;超过临界胶团浓度后浊点下降。  相似文献   

8.
利用阴阳离子表面活性剂复配技术,在克拉玛依油田实际油水体系中获得了超低界面张力.通过添加非离子保护剂的第三组分,阴阳离子表面活性剂混合体系在克拉玛依油田回注水体系中的溶解度大大提高.确定了相关体系能够获得超低界面张力的表面活性剂的浓度和混合的比例范围,在克拉玛依油田的多个实际油水体系中获得了具有较大复配比例和较低表面活性剂浓度的实际配方,其中部分体系油水界面张力可接近10-4mN·m-1.同时,这类阴阳离子表面活性剂混合体系具有很好的抗吸附能力,在石英砂吸附72 h后体系依然呈现优良的超低界面张力.  相似文献   

9.
膨胀石墨对油亲和吸附分析   总被引:13,自引:0,他引:13  
膨胀石墨对油亲和吸附分析曹乃珍沈万慈温诗铸(清华大学,北京100084)金传波(山东省临沂电大,临沂276000)关键词膨胀石墨油吸附膨胀石墨表面和内部有许多网络状的孔,表面积较大,因而有很好的吸附能力[1],特别对于较大的非极性有机分子有较强的吸附...  相似文献   

10.
卟啉类的光电极在分子固体液体接界光伏打电池工作中已得到研究。本文用阴离子型表面活性剂在固体表面上的特性吸附等温线来分析此种离子浓度对数函数与光伏打效应增长的关系,并研究了表面活性剂烷基链长、极性基、阳离子型表面活性剂及非离子型表面活性剂对光伏打效应增强的影响。内Helmholtz层结构与参量变化对光伏打效应也起重要作用。  相似文献   

11.
The shape of expanded graphite is a netted and hollow structure.It is very easy to adsorb molecules and adsorption power is better. The research has proved:the expanded graphite had its ability to adsorb weigh oil etc. The capacity of adsorptive materials has been expressed by the iodimetric adsorption value, but the iodimetric adsorptive value of expanded graphite has not been reported until so far.The paper measures the iodimetric adsorption value by the iodimetry, and the apparatus is used easily and simply. The operation is not more difficult and the accuracy is higher, and the reagent is usual.  相似文献   

12.
A method is described for the determination of non-ionic surfactants in the concentration range 0.05–2 mg l-1.Surfactant molecules are extracted into 1,2-dichlorobenzene as a neutral adduct with potassium tetrathiocyanatozincate(II) and the determination is completed by atomic absorption spectrometry. With a 150-ml water sample, the limit of detection is 0.03 mg l-1(as Triton X-100).The method requires a single phase separation step, is applicable, without modification, to fresh, estuarine and sea-water samples and is relatively free from interference by anionic surfactants; the presence of up to 5 mg l-1 of anionic surfactant (as LAS) introduces an error of no more than 0.07 mg l-1 (as Triton X-100) in the apparent non-ionic surfactant concentration.  相似文献   

13.
本文研究了胶束介质对邻苯二胺的酶催化氧化产物2,3-二氨基吩嗪的光谱性质的影响,发现胶束介质对其吸收光谱影响很小,非离子表面活性剂对其荧光具有强烈的增敏作用,荧光量子效率可提高近十倍。进一步研究表明,非离子表面活性剂对2,3-二氨基吩嗪的增敏原因在于其增溶作用及给电子效应。  相似文献   

14.
In this report we have studied micellization process of anionic, cationic and non-ionic surfactants using N,N-dimethylaminonapthyl-(acrylo)-nitrile (DMANAN) as an external fluorescence probe. Micropolarity, microviscosity, critical micellar concentration of these micelles based on steady state absorption and fluorescence and time resolved emission spectroscopy of the probe DMANAN show that the molecule resides in the micelle-water interface for ionic micelles and in the core for the non-ionic micelle. The effect of variation of pH of the micellar solution as well as fluorescence quenching measurements of DMANAN provide further support for the location of the probe in the micelles.  相似文献   

15.
Tsubouchi M  Tanaka Y 《Talanta》1984,31(8):633-634
The solvent extraction of non-ionic surfactants with sodium hydroxide and tetraphenylborate has been studied, and a method developed for the determination of non-ionic surfactants by two-phase titration. A hydrophobic indicator system was used. The method is valid only when the concentration of anionic surfactant in the sample solution is lower than 1 x 10(-4)M.  相似文献   

16.
A method based on the separation of non-ionic surfactants (NS) in the PTFE capillary trap with final determination by the indirect adsorptive stripping tensammetry has been developed. The method is suitable for NS determination in river water, raw and treated sewage within the range of 2-10,000 μg l−1. The sample volume varies between 0.1 and 50 ml depending on NS concentration, and the time necessary for a single determination is approximately 15 min. This is several orders of magnitude better than determination with the recommended BiAS method. In environmental samples, recoveries ranges from 81 to 95% and precision ranges from 3 to 10%.  相似文献   

17.
A radiometric method for the determination of non-ionic surfactants of ethylene oxide type has been elaborated. The principle of the method is the formation of an associate133Ba-non-ionic surfactant — dicarbolide and its extraction into a mixture nitrobenzene-chloroform /41/. The extracted activity of133Ba is proportional to the non-ionic surfactant concentration in the sample. The factors influencing the determination of non-ionic surfactants in the real waste solution after washing have been studied. The possibility of the determination of non-ionic surfactants by the calibration graph method and by the method of standard addition was verified.  相似文献   

18.
《Analytical letters》2012,45(11):567-576
Abstract

A novel procedure for the analysis of non-ionic surfactants is reported. The method relies on extraction of a cobaltithiocyanate adduct from an aqueous sample into a benzene phase. The amount of cobalt extracted was determined by atomic absorption and correlated linearly with the corresponding surfactant concentration in the aqueous specimen. Relevant pollution levels in the Atlantic Ocean were estimated rapidly with a precision and accuracy of 10% or better.  相似文献   

19.
Two synthetic pathways have been elaborated to prepare new series of highly fluorinated sulfamates with excellent yields. Surface tension measurements at the air/water interface showed that these compounds constitute new excellent non-ionic surfactants exhibiting high surface activity in the range of the best non-ionic fluoro surfactants already described in the literature. The most important feature of this work is that, in comparison with the classical non-ionic fluoro surfactants, these sulfamates are easily synthesized in a monodisperse form from classical and relatively non-toxic starting materials. The critical micelle concentration (CMC), the maximum surface excess concentration (Γ) and the minimum area per molecule (a) have been calculated from the surface tension measurements on surfactant aqueous solutions. Relationships have been established between the length of both the fluorinated tail and hydrocarbon spacer linking the hydrophobic tail to the hydrophilic head, and the interfacial properties.  相似文献   

20.
Cationic, anionic and non-ionic surfactants adsorb readily from aqueous solution on to Amberlite XAD 4. The ionic surfactants cause the pH of the solution in contact with the resin to differ from that in the bulk of solution, cationic surfactants increasing the interfacial pH and anionic surfactants decreasing it. This causes a shift in the pH transition interval of a co-adsorbed pH indicator when measured with respect to the bulk solution. The quantity of ionic surfactant adsorbed tends to a constant value (presumably monolayer coverage) with increasing solution concentration, this amount being a function of the individual surfactant, whereas non-ionic surfactants readily form multilayers. Significant adsorption occurs when the surfactant possesses at least 14 carbon atoms.  相似文献   

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