重质油和焦油的族组成分析

本文采用高效液相色谱、气相色谱、过滤一称重联合分析法对含有溶剂的焦油、重质油的烃族组成进行了分析。给出样品的烷烃、芳烃、非烃和沥青质四大烃族组成，还给出了样品芳烃分布。     

薄层色谱-火焰离子检测技术在重质油族组成分析中的应用

报道了ＴＬＣ－ＦＩＤ技术在重质油族组成分析中的应用。在本文提供的方法下,可对重质油中族组成（饱和烃,芳香烃写,胶质等）进行有效分离和检测。方法的重复性优于经典柱色谱。该技术居有快速,准确,样品及溶剂用量少等特点。在给定试验条件下,原油的种类和实际点样量不影响ＦＩＤ的响应值。     

薄层色谱-氢火焰离子检测分析重质油的族组成

报道了薄层色谱—氢火焰离子检测法在重质油的族组成分析中的应用。方法可有效分离和检测重质油的族组成(饱和烃、芳香烃、胶质等)。该方法具有快速、准确、样品及溶剂用量少等特点。在一定试验条件下，原油的种类和实际点样量不影响氢火焰离子检测的响应值。     

棒状薄层色谱/氢火焰检测法在石油重质油烃组成分析上的应用

在石油重质油的烃组成分析中,液固色谱,质谱和高效液相色谱等已被广泛采用。但是,这些方法均存在着一些缺点,如分析时间长、定量困难等。棒状薄层色谱/氢火焰检测(TLC/FID)法则较好地克服了上述缺点。本文扼要叙述了TLC/FID法的分析原理、试验技术和在石油重质油烃组成分析中的应用实例,并对该技术的发展前景提出了看法。     

探讨薄层色谱在窄馏分重油族组成分析中的应用

建立了快速测定窄馏分重质油族组成的薄层色谱/氢火焰检测(TLC/FID)法.用两种展开剂可以将试样很好的分成饱和烃、芳烃、胶质和沥青质.本方法与经典的柱色谱法有较好的对应关系.     

红外光谱法研究重质油分子的轻度热转化

为了从分子水平快速经济地分析重质油在热转化过程中的变化规律，利用四种模型化合物萘、四氢萘、十氢萘和正庚烷组成的混合体系来模拟重质油及其热转化缩合产物分子的基本组成，研究其红外吸收特性与平均分子参数（亚甲基和甲基的数目之比 N CH2/NCH3、芳氢率faH、芳香环系氢碳原子比NHar/NCar等）的关系。将重质油焦化重蜡油馏分进行轻度热转化，利用不同强度的系列溶剂将热转化产物的重质馏分顺序分离成系列溶剂族组分，将这些族组分进行红外分析。结果表明，混合物系列模拟体系的〖ＷＴＢＸ〗f〖ＷＴＢ１〗aH同其红外吸收在2750cm－1～3100cm－1的3000cm－1～3100cm－1强度分率（S3000~3100/S2750~3100）之间存在良好的线性关系，同时NCH2/NCH3 同2920cm－1和2960cm－1处的吸光度比值A2920/A2960之间也存在良好的线性关系。依据这些关系式可以合理解释重质油分子在热转化过程中分子结构的变化规律。随着重质油热转化的进行，NCH2/NCH3 饱和烃分子先增大后减小，芳香性族组分分子则持续降低；faH或NHar/NCar芳香性族组分分子呈现升高的趋势。     

气-液色谱联合分析煤油共炼产物族组成

建立了一项可以直接分析溶液中焦油和重质油族组成的方法。以高效液相色谱(HPLC)配以气相色谱(GC)完成分析检测。分析了煤油共处理(煤油共炼)中，各种原煤、不同催化剂、不同煤油比及操作条件对产品族组成的影响。     

应用TLC/FID分析重质油的族组成

〕本工作建立了应用薄层色谱氢焰扫描分析超临界抽提重质油族组成的方法,样品从分离到检定仅需一小时,并且可同时进行十个样品的分析。定量线性关系良好,准确度在薄层色谱允许误差范围之内。     

重质油分子化学结构分析及性质预测

对重质油HVGO基本物性和化学结构进行了详细分析和研究.利用实验得到的核磁共振氢谱、相对分子质量、红外光谱等数据,采用改进的Brown-Ladner方法,获得重质油的化学平均结构为C24H38S0.33N0.04.并采用分子动力学与密度泛函相结合的方法,获得重质油平均分子的最可几空间构象,分析其相关电子性质可知,苯环的电子云密度较大,较易被吸附在分子筛催化剂表面,发生催化反应,由此建议加工此类重质油的催化剂应采用具有梯级孔道分布的催化剂以保证裂解性能和产品选择性.     

兖州煤与催化裂化油浆共处理及其重质产物组成性质的初步研究

采用石家庄催化裂化油浆和兖州煤共处理，考察了反应条件对兖州煤转化及产物分布的影响，并应用棒状薄层色谱分析了共处理重质产物族组成的变化规律。结果表明，催化裂化油浆与兖州煤共处理，可大大提高兖州煤的转化率，共处理既可得到部分轻质油品，又可得到相当量的重质产物。ＴＬＣ／ＦＩＤ分析表明，催化裂化油浆与兖州煤共处理的重质产物与商用高等级道路沥青族组成近似，重质产物可用于制备高等组道路沥青。     

PLS方法辅助TLC/FID技术测定石油沥青的族组成

测定了不同来源的渣油、不同改性工艺沥青的薄层色谱图，提取了谱图特征变量，以偏最小二乘方法为数学工具，通过经典柱色谱法取得基础数据，建立渣油沥青的薄层色谱(TLC)-族组成模型。采用该模型预测待测样品的族组成，并与经典柱色谱法的测定结果相比，饱和烃质量分数、芳烃质量分数和胶质质量分数的相关系数分别为0．9765，0．9901和0．9937。测定结果与经典柱色谱法的测定结果相一致。     

棒状薄层色谱/氢火焰法分析磺化酞菁钴的组成

研究建立了一种采用棒状薄层色谱／氢火焰离子检测（TLC／FID）对磺化酞菁钴组成进行定性、定量分析的方法。用薄层色谱并结合质谱分析 表明工业磺化酞菁钴中含有一磺化酞菁钴的两种同分异构体,二磺化酞菁钴的5种同分异构体及三磺化酞菁钴;用棒状薄层色谱／氢离子火焰检测方法可以对磺化酞菁钴中各组分进行定量分析。该方法操作简便,测定时间短,灵敏度高,可用于磺化酞菁钴工业合成的产品质量控制。     

Analysis of biodiesel conversion using thin layer chromatography and nonlinear calibration curves

Biodiesel (BD) is a fuel produced by the (trans)esterification reaction between the components of vegetable oil (or animal fat) and an alcohol. The presence of several substrates complicates analytical separation of the mixture, yet understanding of the complex reaction kinetics requires acquisition of a large body of data. The two well-established methods of gas chromatography (GC) and HPLC are time consuming and expensive when analyzing multiple samples. Additionally, it is not always possible to record all the reactants on one elution profile. We examined applicability of thin layer chromatography (TLC) for this purpose, where the detection was based on either flame ionization detector (FID) or a modified staining procedure. The suggested staining method gave no background and appeared well suited for quantitative analysis. The relevant calibrations are presented, and the general principles of analysis of nonlinear responses are discussed. Several experimental samples were produced by enzymatic conversion of rapeseed oil to BD. One reaction step resulted in 85-95% conversion (6h). The second step (after removal of glycerol and water) increased the yield to 97-98%. All components of the mixtures were separated and quantified. Relation of the BD contents measured by TLC and GC gave the values of 1.03±0.07 (TLC-staining) and 0.95±0.04 (TLC-FID), indicating applicability of the TLC-methods.     

Separation of paralytic shellfish poisoning toxins on Chromarods-SIII by thin-layer chromatography with the Iatroscan (mark 5) and flame thermionic detection.

Thin-layer chromatography (TLC) on Chromarods-SIII with the Iatroscan (Mark-5) and a flame thermionic detector (FTID) was used to develop a rapid method for the detection of paralytic shellfish poisoning (PSP) toxins. The effect of variation in hydrogen (H2) flow, air flow, scan time and detector current on the FTID peak response for both phosphatidylcholine (PC) and PSP were studied in order to define optimum detection conditions. A combination of hydrogen and air flow-rates of 50 ml/min and 1.5-2.0 l/min respectively, along with a scan time of 40 s/rod and detector current of 3.0 A (ampere) or above were found to yield the best results for the detection of PSP compounds. Increasing the detector current level to as high as 3.3 A gave about 130 times more FTID response than did flame ionization detection (FID), for PSP components. Quantities of standards as small as 1 ng neosaxitoxin (NEO), 5 ng saxitoxin (STX), 5 ng B1-toxins (B1), 2 ng gonyautoxin (GTX) 2/3, 6 ng GTX 1/4 and 6 ng C-toxins (C1/C2) could be detected with the FTID. The method detection limits for toxic shellfish tissues using the FTID were 0.4, 2.1, 0.8 and 2.5 micrograms per g tissue for GTX 2/3, STX, NEO and C toxins, respectively. The FTID response increased with increasing detector current and with increasing the scan time. Increasing hydrogen and air flow-rates resulted in decreasing sensitivity within defined limits. Numerous solvent systems were tested, and, solvent consisting of chloroform: methanol-water-acetic acid (30:50:8:2) could separate C toxins from GTX, which eluted ahead of NEO and STX. Accordingly, TLC/FTID with the Iatroscan (Mark-5) seems to be a promising, relatively inexpensive and rapid method of screening plant and animal tissues for PSP toxins.     

Morphology and grafting in polybutylacrylate-polystyrene core-shell emulsion polymerization

The morphology of polybutylacrylate–polystyrene (PBA–PS) core-shell latex particles prepared by seeded emulsion polymerization was investigated as a function of the addition method of styrene (St). The thin layer chromatography/flame ionization detector (TLC–FID) technique was used to characterize the morphology of the core-shell latexes. It was found that grafting PS to the PBA core occurs during seeded emulsion polymerization. The percentage of grafting depended on the method of addition of St, being greatest for the batch reaction, less for the preswollen batch reaction, and least for the semibatch reaction. Upon aging the PBA core-polymer migrated out of the latex particles with a low degree of grafting to form dumbellshaped particles, whereas the PBA–PS core-shell particles with a high degree of grafting remained spherical because of the emulsifying ability of graft copolymer.     

Organic fuelled flames in selective ionization detectors for chromatography

Summary The selectivities of two flame-based ionization detectors identified as a Remote FID (RFID) and a Flame Thermionic Ionization Detector (FTID) have been improved by introducing methane as a fuel for the flame. Both the RFID and FTID feature a detector struture in which the ionization polarizer and collector are located several centimeters downstream of an oxygen-rich flame, rather than immediately adjacent to the flame as in a flame ionization detector. The RFID detects long-lived negative ions produced in the flame by the combustion of lead, tin, phosphorus, or silicon compounds. The FTID re-ionizes and detects neutral electronegative products generated by combustion of nitrogen, halogen, or phosphorus compounds. An organic-fuelled RFID can detect 1 pg Pb (Sn, P)/sec with a selectivity of the order of 10⁶ versus hydrocarbons. An organic fuelled FTID is applicable to detection of compounds at nanogram and higher levels. FTID selectivity for PCB compounds in a transformer oil matrix is of the order of 10⁵1. The improved selectivity achieved by using an organic-fuelled flame is also applicable to the detection of phospholipid and other non-volatile N, P, or Cl compounds using an FID/FTID detector accessory for a TLC/FID analyser.     

Photoionization assessment of C3-C5 alkadienes and alkenes in urban air.

Hydrocarbons from samples of traffic-polluted urban air were separated by gas chromatography on an aluminium oxide column and assessed simultaneously by photoionization detection (PID) and flame ionization detection (FID) after effluent splitting. The 10.2 eV photoionization detector selectively detects alkadienes and alkenes but not alkanes and alkynes in the C3-C5 region. The maximum PID/FID response ratio for alkadienes and alkenes is also obtained in this region. The analytical system as a whole is particularly favourable for the C3-C5 alkenes. Analytical data are given for propadiene, 1,3-butadiene, propene, butenes and pentenes.     

Process parameters and their effect on grafting reactions in core/shell latexes

The grafting of methyl methacrylate (MMA) onto polybutadiene (PB) latexes prepared by seeded emulsion polymerization at 50°C was investigated as a function of: (a) initiator concentration used in the secondary polymerization, (b) monomer-to-polymer ratio, (c) the specific surface area of the seed latex, and (d) the degree of conversion. The thin layer chromatography/flame ionization detection (TLC/FID) technique was used to determine the proportion of graft copolymer in the core/shell latex, It was found that grafting PMMA onto PB depended upon the concentration of initiator, decreasing as the concentration was increased. The amount of grafting increased with increasing specific surface area of the seed latex, while the molecular weight of the acetone-soluble graft copolymer decreased. The amount of graft copolymer was found to decrease concurrently with increasing monomer-to-polymer ratio and degree of conversion. These results suggest a hydrogen abstraction mechanism in the formation of graft PB–PMMA through a chain transfer process.