Separation and analysis of six fractions in low temperature coal tar by column chromatography

The low temperature coal tar(CT)is taken as the raw material,and the extraction and column chromatography are used for detailed and accurate characterization in this paper.The n-heptane soluble fraction(CT-HS)and insoluble fraction(CT-HI)were obtained by n-heptane Soxhlet extraction.The extraction rate of CT-HS reached 92.79%(mass),which indicated that there are few heavy compounds in it.Further,different solvents(methylbenzene,benzene,ethyl acetate,methylbenzene-ethanol)were used to elute CT-HS by chromatographic column to obtain five fractions(saturates,aromatics,heteroatoms,phenolics and resins,named CT-SA,CT-AR,CT-HE,CT-PH,CT-RE,respectively).The yields of CTSA,CT-AR,CT-HE,CT-PH,CT-RE are 42.12%,10.43%,2.19%,9.50%and 6.63%(mass),respectively.Gas chromatography-mass spectrometry analysis of eluting components show that alkanes are the main components in CT,followed by polycyclic aromatics,and the corresponding fractions are CT-SA and CT-AR,respectively.The relative content of aliphatics in CT-SA is 76.93%,and the relative content of aromatics in CT-AR is 75.05%.This separation technology effectively separates and enriches different components in CT,and the activation energy required for the pyrolysis process of a single eluting fraction is lower than that of CT,which is expected to provide an important reference for the separation,analysis and conversion of complex oil products such as coal-oil co-processing products,coal tar and other complex heavy carbon oil products.

Separation and purification of deoxynivalenol(DON) mycotoxin from wheat culture using a simple two-step silica gel column chromatography

Deoxynivalenol（DON） is a type B trichothecenes mycotoxin produced by several Fusarium species, often found in foodstuffs for humans and animals. DON is in great demand for the toxicological researches both in vivo and in vitro. In this work, wheat culture was inoculated with a Fusarium graminearum PH-1 strain for DON production. The solvent system for crude extraction was acetonitrile-water（84：16, v/v）. A simple two-step silica gel column chromatography was employed to separate the DON mycotoxin from wheat culture, combined with preparative high performance liquid chromatography（preparative HPLC） to purify the compound. The solvent system for the second silica gel column chromatography was methylene chloride-methanol（17：1, v/v）, which provided a good elution effect selected on thin layer chromatography（TLC）. The target compound was identified by HPLC, and the chemical structure was confirmed by mass spectrometry（MS） and ~1H and ^（13）C nuclear magnetic resonance（NMR） spectroscopy. A total of 433 mg of purified DON was obtained from 1 kg of wheat culture, with a purity of 99.01%. The study had provided an easy-operating and cost-effective method to isolate an expensive compound in a simple way.

Separation of liquefied product of Salix psammophila by column chromatography and structure analysis of its components

The liquefied product of Salixpsammophila wood was separated by thin-layer chromatography （TLC） and column chromatography, and its structure was identified by nuclear magnetic resonance （NMR） spectra in our study. The separation result indicates that the sample of liquefied S. psammophila contained at least two categories of components. The structure of the main components was guaiacyl C-1, C-2 of the hydroxyphenyl propane, i.e., the aromatic nucleus protons of lignin. Degradation and polycondensation reactions occurred when the S. psammophila wood was liquefied in phenol. Polycondensation reactions occurred among the depolymerization products from cellulose, the aromatic depolymerization products from lignin and the products of the displacement reactions between phenoxide ion and cellulose.

Separation of Inorganic Anions Using Methacrylate-Based Monolithic Column Modified with Trimethylamine in Ion Chromatography Capillary System

Methacrylate-based monolithic column was prepared in fused-silica capillary (80 ′ 0.32 mm i.d.) by in situ polymerizetion reaction using glycidyl methacrylate as monomer;ethylene dimethacrylate as crosslinker;1-propanol, 1,4-butanediol, and water as porogenic solvents. The monolith matrix was modified with trimethylamine to create strong anion exchanger via ring opening reaction of epoxy groups. The morphology of the monolithic column was studied by using Scanning Electron Microscope (SEM). This column had good mechanical stability and permeability. The effects of various mobile phases for separation of inorganic anions were investigated. Iodate, bromate, nitrite, bromide, and nitrate were separated within 11 min using100 mMpotassium chloride as mobile phase and detected at 210 nm. This method showed good precision of retention time, acceptable linearity and good sensitivity. Under the optimum condition, the RSD of the retention time was in the range of 1.09%-1.75% (n = 6). The calibration curve showed linear relationships between the peak area and the concentration. The limits of detection (LOD) and the limits of quantitation (LOQ) were between 0.08-0.18 mM and 0.26-0.61 mM, respectively. This method was applied to the determination of inorganic anions in tap water and ground water samples.

Research Progress on the Separation of Alkaloids from Chinese Medicines by Column Chromatography

Alkaloids have a variety of bioactivities and great development value in the fields of pharmaceuticals, cosmetics and health food. Column chromatography is a common method for preparing alkaloids. In this paper, the research status of the separation and purification of alkaloids from Chinese medicines by column chromatography is reviewed, and the factors that influence the refining of alkaloids via a macroporous adsorption resin, ion exchange resin and silica gel are summarized. The thermodynamic and kinetic modeling methods for the static adsorption of adsorbents are also reviewed in this paper. It is suggested that the modeling method of the column chromatography process be deeply studied to establish a more stringent quality control method for sampling liquid and to strengthen the online detection of the chromatography process to improve the refining effect of alkaloids.

Group separation and analysis of a carbon disulfide-soluble fraction from Shenfu coal by column chromatography

A carbon disulfide-soluble fraction (CDSSF) from Shenfu coal was separated into five fractions by silica-gel column chromatography using hexane and n-hexane/ethyl acetate binary eluent. The five fractions include four clear group fractions and a nonpolar fraction. All the fractions were analyzed by GC/MS. A total of 204 compounds were detected from the original CDSSF and its further separated fractions, with 173 compounds more than those detected by studying the original CDSSF directly. The results demonstrate a clear group separation by column chromatography in coal organic components and a more accessibility to coal components compared with the solvent extraction only.

Optimization of Preparative Separation and Purification of Total Polyphenols from Sargassum tenerrimum by Column Chromatography

Polyphenols from the ethanol extracts of Sargassum tenerrimum (ST) with potent antiallergic effects were studied to optimize separation process through column chromatography. The adsorption and desorption characteristics of three widely used adsorbents: macroporous resin, silica gel, and polyvinylpolypyrrolidone (PVPP), were critically evaluated respectively and studied for the optimization of preparative separation of polyphenols. Static operations on these adsorbents showed that macroporous resin had the best adsorption and desorption capability among the three adsorbents. Dynamic adsorption and desorption with macroporous resin packed column were also conducted to optimize the parameters such as: with the optimal values shown in brackets, the concentration of extract solution (4 times diluted), pH value (6?7), adsorption speed (3 BV h-1, bed volumes/per hour), concentration of ethanol (80%), elution speed (3 BV h-1) and elution volume (7 BV). The chromatographic process so optimized gave a purity of 62.43% from the crude polyphenols, providing a promising basis for large scale preparation of bioactive polyphenols upon further scaling up tests.

Column Chromatography: A Facile and Inexpensive Procedure to Purify the Red Dopant DCJ Applied for OLEDs

DCJ, one of the DCM derivatives, has been used as a laser dye and a red emitter or a red dopant for OLED devices in recent decade. 4-(dicyanomethylene)-2-methyl-6-(julolidyl-9-enyl)-4H-pyran (DCJ) containing julolidine group has been synthesized for use as a red fluorescent dye molecule in organic light-emitting di- odes (OLEDs). In this paper, we reported a facile, simple and inexpensive procedure of purification of DCJ without necessity of HPLC analysis. The maximum absorption, emission, quantum efficiency are increasing in DCJ with the electron-donating of julolidine group.

Determination of Five Organic Acids in Radix Isatidis by Column Partition Chromatography and Capillary Zone Electrophoresis

Aim To determine five organic acids in Radix lsatidis. Method The extraction method and the column partition chromatographic conditiom were studied. Then a capillary zone dectrophorefic method was set up for the determina-tion. Results The linear ranges of quinazolinone acid, n-anthranilic acid, benzoic acid, salicylic acid, and syringic acid were 5.52 - 92.0μg·mL^-1 , 5.12 - 102μg·mL^-1 , 2.28 - 84.4μg·mL^-1, 4.78 - 159 μg·mL^-1, and 1.74- 87.0μg·mL^-1 respectively. Conclusion The established method is accurate and simple.

Determination of petroleum sulfonates in crude oil by column-switching anion-exchange chromatography

A column-switching anion-exchange chromatography method was described for the separation and determination of petroleum monosulfonates （PMS） and petroleum disulfonates （PDS） in crude oil that was simply diluted with the dichloromethane/methanol （60/40）. The high performance liquid chromatography （HPLC） system consisted of a clean-up column and an analytical column, which were connected with two six-port switching valves. Detection of petroleum sulfonates was available and repeatable. This method has been successfully applied to determine PMS and PDS in crude oil samples from Shengli oil field.

Identification of Glyphosate Herbicide with Ion Chromatographic Column Switching Method

[Objective] The paper was to establish the method for quantitative analysis of glyphosate herbicide and identification of salt type. [Method] Using ion chromatographic column switching method,cations( sodion,ammonium ion,potassium ion,dimethonium ion and isopropylamine ion) and glyphosate anion in glyphosate salt were determined with Thermo IonP ac SCS1 cation exchange column and Thermo IonP ac AS14 anion exchange column,and external standard method was used for quantification. [Result] Various components showed good linear relationship within the linearity range,and the correlation coefficient r was greater than 0. 999; the relative standard deviation of retention time and peak area were less than 0. 13% and 1. 22%,respectively; the recovery was 98. 22%-99. 97%.[Conclusion] The method is precise,accurate and simple,and can be used to determine the active ingredients of glyphosate herbicide.

Simultaneous enantioseparation and simulation studies of atenolol,metoprolol and propranolol on Chiralpak^■IG column using supercritical fluid chromatography

Enantioseparation of threeβ-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate)immobilized chiral stationary phase using supercritical fluid chromatography(SFC).The effect of organic modifiers(methanol,isopropanol and their mixture),column temperature and back pressure on chiral separation ofβ-blockers was evaluated.Optimum chromatographic separation with respect to resolution,retention,and analysis time was achieved using a mixture of CO_(2) and 0.1%isopropyl amine in isopropanol:methanol(50:50,V/V),in 75:25(V/V)ratio.Under the optimized conditions,the resolution factors(Rs)and separation factors(a)were greater than3.0 and 1.5,respectively.Further,with increase in temperature(25-45℃)and pressure(100-150 bars)there was corresponding decrease in retention factors(k),a and Rs.However,a reverse trend(a and Rs)was observed for atenolol with increase in temperature.The thermodynamic data from van’t Hoff plots revealed that the enantioseparation was enthalpy driven for metoprolol and propranolol while entropy driven for atenolol.To understand the mechanism of chiral recognition and the elution behavior of the enantiomers,molecular docking studies were performed.The binding energies obtained from simulation studies were in good agreement with the elution order found experimentally and also with the free energy values.The method was validated in the concentration range of 0.5-10μg/m L for all the enantiomers.The limit of detection and limit of quantitation ranged from 0.126 to 0.137μg/m L and 0.376-0.414μg/m L,respectively.The method was used successfully to analyze these drugs in pharmaceutical preparations.

基于在线柱切换液相色谱技术的红霉素软膏含量测定研究

目的建立在线柱切换高效液相色谱法测定红霉素软膏中主药含量的方法,为相关制剂的质量控制提供有效手段。方法样品经80℃提取后直接进样,柱切换系统下,采用C_(18)(50 mm×2.1 mm,5μm)色谱柱初步分离,2.5 min后转入C_(18)(150 mm×2.1 mm,5μm)柱进行分析,流速0.2 mL·min^(-1),柱温35℃。结果红霉素在1~100μg·mL^(-1)范围内线性关系良好(r=0.9994);平均加样回收率大于96.9%;日内和日间精密度小于1.29%(n=6)。结论本研究改进样品提取方法,并通过在线柱切换完成目标组分的净化和富集,该方法操作简单、准确灵敏、稳定性好,可用于红霉素软膏的含量测定。

柱前衍生-高效液相色谱法测定巴戟天中氨基酸含量及营养价值评价

建立柱前衍生-高效液相色谱法测定巴戟天中氨基酸含量,采用氨基酸比值系数法评价其营养价值。采用盐酸水解法制得巴戟天氨基酸供试品溶液,以异硫氰酸苯酯和三乙胺为柱前衍生化试剂,采用高效液相色谱法,使用Ultimate Amino Acid色谱柱(4.6 mm×250 mm,5μm)以0.1 mol/L无水乙酸钠-乙腈为流动相,梯度洗脱,柱温40℃,检测波长为254 nm,测定氨基酸含量;通过氨基酸比值、氨基酸比值系数、氨基酸比值系数分等评价其营养价值,并采用系统聚类和主成分分析对其进行分类分析。结果表明,15种氨基酸线性关系良好,相关系数r≥0.9996。16份巴戟天氨基酸总含量为17.87~102.15 mg/g,均检测到15种氨基酸,其中包含6种必需氨基酸,占总氨基酸含量的14.15%~32.06%;8种药用氨基酸,占总氨基酸含量的45.20%~56.31%。限制氨基酸为苏氨酸和亮氨酸,氨基酸比值系数分为33.87~61.31。不同巴戟天样品氨基酸组成相关性显著;主成分分析提取2个主成分,累计方差贡献率为97.085%,可将16批巴戟天分为三类。该实验测定方法简单有效,可同时分离测定15种氨基酸,精密度与重复性良好,有较高的药用价值,可为巴戟天的品质分析和资源开发利用提供参考。

荔枝草中乙酸乙酯层化学成分分析

目的:对荔枝草的乙酸乙酯层进行化学成分研究。方法:采用硅胶柱色谱、中压快速色谱和Sephadex-LH凝胶色谱等方法进行分离纯化,运用波谱手段、理化性质和文献对照进行各单体化合物的结构鉴定。结果:从荔枝草的乙酸乙酯层分离出2个单体化合物,分别鉴定为泽兰黄酮和高车前素。结论:采用中压色谱能从荔枝草乙酸乙酯萃取层中快速大量提取泽兰黄酮和高车前素,该方法省时、简便、高效,值得推广应用。

气相色谱-质谱法测定酒店空气中7种苯系物

试验运用气相色谱-质谱法测定扩建装修酒店空气中7种苯系物,采用活性炭管采样和二硫化碳解吸,同时对质谱参数和色谱柱进行优化。结果表明,色谱柱能有效分离苯系物中7种待测组分,实现各组分峰完全分离。苯系物具有良好线性关系,相关系数R^(2)>0.999,检出限介于0.60~2.20μg/L,加标回收率为93.9%~98.2%,相对标准偏差为1.8%~4.0%,准确度和精密度良好。苯系物质量控制样品测定表明,该方法符合质控范围。气相色谱-质谱法可用于检测酒店空气中7种苯系物,方法准确可靠,灵敏度高。

高温煤焦油中稠环芳烃和氮杂环芳香族化合物的分离富集

煤焦油是高附加值稠环芳烃的主要来源,甚至是某些芳香族化合物的唯一来源。先用纯石油醚,再用乙酸乙酯体积分数为5%和30%的石油醚/乙酸乙酯混合溶剂依次作为洗脱剂,采用柱层析法对高温煤焦油的石油醚萃取物洗脱,得到洗脱液1-3(E_(1)-E_(3))。在E_(1-6)和E_(1-10)中富集到5种四环稠环芳烃,其中荧蒽在E_(1-10)中相对含量达71.02%。此外,在E_(2-2)中富集到6种酚类和9种氮杂环芳香族化合物,在E_(3-2)中富集到7种1~4环的氮杂环芳香族化合物。

毛细管顶空气相色谱法高灵敏监测花生大豆根瘤生物固氮能力

建立了测定花生和大豆根瘤菌生物固氮能力的毛细管顶空气相色谱法,利用固氮酶还原乙炔气体为乙烯的经典方法,实现了高浓度乙炔中痕量乙烯的高灵敏分析。利用顶空进样方式,分离柱采用HP-PLOT Q毛细管色谱柱,程序升温,采用氢离子化检测器,对乙烯标准气体进行了定量分析。乙烯检测范围宽为0.125~30000μmol/mol,相关系数为0.9996,检测限(LOD)为0.0341μmol/mol,检出限优于已有报道。该方法检测精密度好,5次检测的相对标准偏差为2.32%。乙烯样品的回收率为95.8%~110%,相对标准偏差为1.54%~3.47%。同时,对乙烯和实际样品进行检测时,与GDX-502填充柱的传统气相色谱法的测定结果一致,表明所建立的乙烯顶空气相色谱法具有较高的可靠性。此外,该方法分析时间缩短至3 min,利用自动进样方式,检测通量大,适用于花生和大豆根瘤菌中固氮能力的快速准确测定,能满足花生和大豆生物固氮研究中乙炔还原法测定乙烯的需求。

FCC催化剂组元上轻柴油裂化反应焦炭的结构组成

结合柱色谱层析分离、GC/MS和场解析质谱(FDMS)技术,建立了一种可萃取焦的分离检测方法,并考察了不同FCC催化剂组元轻柴油裂化反应焦炭的组成结构。结果表明,在较低反应温度下(400～460℃),Y型沸石上的焦炭含较大比例的可萃取焦,USY沸石的可萃取焦所占比例低于REY沸石的,表明USY沸石上焦炭的分子缩合度高于REY沸石;较高反应温度下(520℃),沸石上的焦炭中95%以上以高缩合度不可萃取焦状态存在。基质上的焦炭中,仅在较低的反应温度下(400℃)含有很少量可萃取焦,焦炭缩合度远高于沸石组分上的焦炭。可萃取焦以多环芳烃(3～8环结构,烷基侧链碳数不大于8)为主要组分;不可萃取焦呈无定形状态,nH/nC比在0.3～0.5之间。

大豆油脱臭馏分重相组分中甾醇酯的柱层析法分离提取

为减少甾醇酯的生产工序,提高大豆油脱臭馏分重相组分中总甾醇得率,采用柱层析法直接分离提取甾醇酯,通过单因素试验考察吸附剂种类、上样量、洗脱剂比例和柱长直比(填料高度与直径比)对甾醇酯产品纯度和得率的影响,确定最佳工艺条件,并对最佳工艺条件下分离提取的甾醇酯产品进行傅里叶红外光谱表征,以及甾醇组成和脂肪酸组成测定。结果表明,柱层析法分离提取甾醇酯的最佳工艺条件为吸附剂为硅胶(粒径50~75μm),上样量0.5 g,洗脱剂比例为正己烷、乙醚、冰乙酸体积比95∶5∶1,柱长直比16∶1。在最佳工艺条件下,甾醇酯产品纯度为(89.90±0.94)%,得率为(96.15±1.49)%;傅里叶红外光谱分析证实提取的产品中含甾醇酯,甾醇酯上的甾醇组成主要为β-谷甾醇、豆甾醇、菜油甾醇,脂肪酸组成主要为亚油酸、油酸、棕榈酸、硬脂酸和亚麻酸。综上,柱层析法无需复杂工序,即可实现大豆油脱臭馏分重相组分中甾醇酯的有效回收。