C60大量、快速分离和电喷雾电离质谱检测

本文用配合沉淀和活性炭吸附相结合的方法，从高级富勒烯含量较高的混合物中，大量、快速分离Ｃ６０，并用电喷雾电离质谱对分离产物进行检测     

富勒烯C60的柱色谱分离法研究

本文提出了由Ｃ（６０）、Ｃ（７０）及少量高级富勒烯混合物（来自电弧汽化石墨所形成的碳灰）中分离出纯度为９９．９％Ｃ（６０）的两种改进的、简便价廉的柱色谱分离法．第一种方法用中性氧化铝作固定机以石油醚与甲苯（Ｖ／Ｖ＝９２．５／７．５）混合液作流动相；另一种方法以活性炭与硅胶作固定相，以甲苯作流动相，柱顶氮压约为０．０１ａｔｍ．本文尚将这两种方法与文献报道的两种相近的方法分别进行了比较．     

锆和铪的色谱分离

 介绍了用二甲基硅酮作固定相的毛细管气相色谱法分离三氟乙酰丙酮合锆和三氟乙酰丙酮合铪的混合物及乙酰丙酮合锆和乙酰丙酮合铪的混合物。用Ｃ＿（１８）键合固定相的反相高效液相色谱法分离上述β－二酮合锆和铪的混合物；讨论了色谱分离中的问题。     

用于富勒烯分离的高效液相色谱固定相

用于富勒烯分离的高效液相色谱固定相陈德朴，郁鉴源，廖沐真，黄贺生，刘凤英，刘梦林（清华大学化学系，北京，１０００８４）（清华大学现代应用物理系）关键词Ｃ_（６０）、Ｃ_（７０）分离，固定相，高效液相色谱目前有关富勒烯的研究是国际上一个非常活跃的研究领域...     

2,4,6-三硝基苯酚改性锆镁复合氧化物固定相分离富勒烯的色谱性能研究

 制备了用于分离C60和C70的2,4,6-三硝基苯酚改性锆镁复合氧化物高效液相色谱固定相,并用元素分析仪、红外光谱仪和比表面积分析仪等对其进行了表征。考察了流动相中甲苯含量和柱温对C60和C70分离的影响。同时考察了以甲苯为流动相,在348 K的柱温下,该固定相分离富勒烯混合物(含3%高富勒烯)的情况。结果表明,2,4,6-三硝基苯酚改性锆镁复合氧化物固定相对富勒烯有较强的保留,并表现出较强的温度关系,提高柱温能提高固定相对富勒烯的分离能力,并具有用于富勒烯制备分离的潜力。     

高富勒烯的富集方法研究

高富勒烯的含量很低，在总的富勒烯混合物中仅点１％左右，将其分离出来一般要经过提取、富集、高效液相色谱分离三个步骤。目前，高富勒烯的富集用得较多是Ｄｉｅｄｅｒｉｃｈ等采用的方法［１～４］，他们将富勒烯混合物在三根中性氧化铝柱中，用正己烷和甲苯（９５／５...     

激光解吸电离质谱法分析富勒烯

论述了用激光解吸电离谱法分析富勒烯。因在电离过程中富勒分子不发生裂解，因此这种方法可直接用于富勒烯混合物的分析而勿需任何预分离。还给出了用本法分析较大、较稳定富勒烯分子的质谱图。     

高富勒烯的提取,分离和分析

采用二硫化碳重结晶富勒烯混合物或二硫化碳二次抽提烟灰以提取高富勒烯（ｈｉｇｈｅｒｆｕｌｅｒｅｎｅｓ，Ｃｎ，ｎ＞７０）。产物经高效液相色谱分析，高富勒烯的含量从１％分别提高到４％和６％；经激光飞行时间质谱证明，产物中除含主要成分Ｃ６０和Ｃ７０以外，还含有Ｃ７６、Ｃ７８、Ｃ８２、Ｃ８４以及更高碳原子的富勒烯。     

色谱法分离纯化富勒烯的研究进展

富勒烯是近年来研究较多的碳笼结构高分子化合物,基分离、纯化是影响该研究领域进展的关键因素。色谱法是目前分离富勒烯的重要手段,本文概述了该法在富勒烯分离、纯化中的应用,着重讨论了高效液相色谱固定相的发展。     

C_（60），C_（70）液相色谱分离方法的研究

 较系统地考察了不同柱系统及不同流动相组成下Ｃ＿（６０），Ｃ＿（７０）的保留规律。在实验的基础上，提出了分离Ｃ＿（６０），Ｃ＿（７０）的最佳柱系统及流动相组成。并在此分离条件下，对高分子量的富勒烯组分进行了分离。     

Temperature effect in separation of fullerene by high-performance liquid chromatography

Summary The effect of column temperature, especially at low temperatures, on the separation of fullerenes on monomeric and polymeric octadecyl silica (ODS) bonded phases has been studied. Decreasing the column temperature induces an increase in selectivity. The best temperature for the separation of fullerenes was determined for both types of ODS phase with n-hexane eluent. The selectivity for higher fullerenes on monomeric phases becomes similar to that on polymeric phases to low temperature. It has been found that as the carbon content of monomeric phases is increased, the selectivity also becomes similar to polymeric phases.     

Fast separation and quantification of C60 and C70 fullerenes using thermostated micro thin-layer chromatography.

Thermostated micro planar chromatography was applied for systematic separation studies of C60 and C70 fullerenes using n-alkanes as mobile phases on TLC and HPTLC plates coated with polyamide, silica gel, aluminum oxide as well as two types of octadecylsilica (C18) sorbents. Retention data were collected at constant temperature at 20 degrees C (+/-0.05 degrees C) using an unsaturated chamber mode with an eluent, such as n-pentane, n-hexane and n-heptane. The separation results under both saturated and unsaturated chamber modes for selected mobile/stationary phases were also examined, and several parameters, including separation factor (alpha) and resolution (R(S)), were compared with data obtained with high-performance liquid chromatography conditions. Interestingly, C60/C70 fullerenes separation performed on HPTLC plates with a developing distance of 45 mm was better for those observed on a 25 cm length analytical HPLC column under similar conditions to that on carbon coverage of the stationary phase, n-hexane as the mobile phase and separation temperature (R(S) = 1.84 and 1.68 for HPTLC, and HPLC, respectively). Moreover the advantage of the planar chromatographic separation of fullerenes studied is a short elution time of less than 6 min. Furthermore, the reported separation protocol shows a capability for the evaluation of fullerenes quantity in commercial samples.     

Separation and identification of higher fullerenes in soot extract by liquid chromatography-mass spectrometry

Summary Two-step liquid chromatographic separation (LC) has been applied to soot extract and the identification of higher fullerenes has been accomplished by LC-MS measurements using an ESI interface. The first separation step is preparative-scale LC using a 50 mm i.d. column packed with monomeric octadecylisilica (ODS) because elution is mainly controlled by relative molecular mass. 39 batches of five fractions each were collected and then as the second separation step each fraction was analysed by analytical-scale LC using a conventional column of a polymeric ODS phase which can elute fullerenes according to shape and structure. This stationary phase can also separate many isomers of higher fullerenes, consequently the existence of several higher fullerenes larger than C₈₆ has been confirmed and their UV-Vis spectra were obtained by the photodiode array detection system coupled to the analytical LC.     

Surfactant coated fullerenes C60 as pseudostationary phase in electrokinetic chromatography

In the present paper, surfactant coated fullerenes C(60) (SC-C(60)) have been proposed as a novedous pseudostationary phase to improve separation of different aromatic compounds. The target analytes were beta-lactams antibiotics, non-steroidal anti-inflammatory drugs and amphenicols. In all cases, the analytes interacted with the pseudostationary phase producing an important enhancement on resolution. The results were compared with those obtained with surfactant coated carbon nanotubes (single-walled and multi-walled nanotubes), showing that in the proposed conditions, fullerenes C(60) were advantageous as interactions between the analytes and the pseudostationary phase were more effective. Finally, the procedure was applied to pharmaceuticals and urine samples, with satisfactory results.     

Use of cerium oxide (CeO(2)) as a packing material for the chromatographic separation of C(60) and C(70) fullerenes

Cerium oxide (CeO₂) was tested as a packing material in liquid chromatography for the separation of C₆₀ and C₇₀ fullerenes. The separation of C₆₀ and C₇₀ fullerenes could be achieved within 20 min by using pure n-hexane as the mobile phase. Furthermore, some higher fullerenes could also be separated in less than 40 min. The peak area was reproducible to a large extent. The separation of fullerenes by liquid chromatography on CeO₂ is shown to be an effective method for their isolation in large amounts. The column efficiency of the CeO₂ column was compared with commercial silica gel and ODS columns. The main advantage of the CeO₂ column is its ability to separate large amounts of fullerenes (C₆₀ and C₇₀) in toluene.     

In-situ carbonizing of coal pitch on the surface of silica sphere as quasi-graphitized carbon stationary phase for liquid chromatography

A novel chromatography stationary phase with a quasi-graphitized carbon modified shell has been developed. Coal pitch was directly carbonized on the surface of porous silica with in-situ carbonization. The carbonized coal pitch coating exhibits some degree of graphitization with a 78 nm-thick layer on the surface of silica and a 0.5 nm-thick layer on the inner surface of the mesopores. Based on the special structure of the graphitized carbon coating, the novel stationary phase can provide multiple interactions such as hydrophobic interaction, π-π interaction and dipole-dipole interaction. The novel composite material exhibited unique separation selectivity and excellent separation efficiency for polar compounds, including imidazoles, nucleosides and pesticides. Besides, the packed column also exhibited great repeatability with the RSDs of the retention time of nucleosides between 0.07%-0.50% (n = 5). Finally, satisfied result was achieved in the separation of fullerenes on the new column, suggesting the great potential in the industrial-scale purification of fullerenes.     

HPLC separation of fullerenes on two charge-transfer stationary phases

Two charge-transfer stationary phases were prepared by immobilizing p-nitrobenzoic acid and naphthyl acetic acid onto silica. The nitrophenyl moiety and the naphthyl moiety were grafted to silica gel through the spacer of aminoalkyl silanes. The HPLC separation of C60, C70, and higher fullerenes on the new stationary phases was also studied. The influence of mobile phase and column temperature on the separation of C60 and C70 was examined, respectively. The retentions of C60 and C70 on the two stationary phases increased with decreasing toluene content in the mobile phase or with increasing column temperature. Higher fullerenes can be separated well using toluene as the mobile phase on the stationary phase of p-nitrobenzoic acid-bonded silica.     

Ordered mesoporous carbon as an efficient and reversible adsorbent for the adsorption of fullerenes

An ordered mesoporous carbon, CMK-3, was synthesized using a mesoporous siliceous material, SBA-15, as the template. CMK-3 was characterized and used for the adsorption of fullerenes C60 and C70. It was found that the adsorption capacity of CMK-3 is 4 times higher than that of activated carbon. The adsorption equilibrium isotherms of C60 and C70 on CMK-3 were studied for both single and binary systems. The reversibility of fullerene adsorption on CMK-3 was also explored. The results showed that CMK-3 is an effective and reversible adsorbent for the separation of fullerenes by adsorption.