Steam as a carrier gas in capillary chromatography

The use of water as a carrier gas in capillary gas chromatography has been considered. Steam and helium have been compared as a mobile phase for separation of alkanes (using the example of chromatograms of diesel fuel) and polyaromatic compounds (SE-30 and HP-5 capillary columns). Steam has been shown to have an advantage. The peak resolution values calculated for the pair of C₁₈/iso-C₂₀ compounds are 4.4 for steam and 3.9 for helium. The Van Deemter relations have been measured and it has been shown that a significantly lower viscosity of steam compared to helium allows for analysis of substances in a wide range of linear velocities with good selectivity. Steam has been shown to hold promise for chromatographic determination of hydrocarbons.     

油田气组分的分析方法——多维色谱法

早期由于色谱柱及分析仪器比较落后以及分离、检测手段的局限，油田气的组分分析操作烦琐、费力、费时且易产生误差。为此，介绍了油田气组分检测的一种新方法--填充柱和毛细管混合色谱柱的多维色谱系统。该方法在Agilent 6890气相色谱仪上配有TCD与FID双检测器、2个电子阀、3根填充柱及1根毛细管柱。在分析油田气时，样品首先被予柱分离为轻质和重质两部分：轻质部分包括乙烷、甲烷和空气，继续在填充柱中进行分离，并在TCD检测器上得到检测；而重质部分的丙烷及更重质烃类组分则被反冲到毛细管柱进行分离，并在FID上得到检测。该方法的突出特点是只注射一次样品，就能实现油田气中轻烃类、非烃类和重质烃类的分离和检测。该方法具有准确度高、精度高、工作效率高等优点。     

人工燃气组份的色谱分析法

介绍用改进的色谱分析法，分析人工燃气全组份。用一台色谱仪，一个ＴＣＤ检测器，一个ＦＩＤ检测器，两根填充柱及一根毛细管柱，以氩气为载气，采用标准样品对照法进行定性分析，峰面积外标法进行定量分析。利用本法可在一次进样时很好地分离检测并计算出１９种组份的体积分数，缩短分析时间。该法操作简便、稳定、可靠、精确度高、重复性好。     

类异戊二烯烷烃非对映异构体的色谱—质谱分离及条件优化研究

运用GC-MS对准噶尔盆地煤样及孤岛稠油样中的饱和烃生物标志化合物进行分析,首次检测到了丰富的无环类异戊二烯烷烃类化合物:iC₁₈(2,6,10-三甲基十五烷)、Pr(2,6,10,14-四甲基十五烷)和Ph(2,6,10,14-四甲基十六烷)及其非对映异构体。并考察了色谱柱类型、长度、程序升温等对类异戊二烯烷烃非对映异构体分离效果的影响,同时确定了程序升温色谱分离类异戊二烯烷烃非对映异构体的最佳条件,对样品中的降姥鲛烷、姥鲛烷、植烷与其非对映异构体进行了分离,对姥鲛烷、植烷的分离度最高可分别达0.7及0.9。      

一种多功能气相色谱仪在天然气分析中的应用

介绍了一种多功能的气路流程,可用于天然气中无机和有机组分的分析,采用两根填充柱和一根石英毛细管柱组成的一种多维的天然气分析系统。通过在不同时间,采用六通阀和十通阀的切换进样实现了天然气中各组分完全分离的目的。采用毛细管分析柱和FID检测器,使系统对烃类组分的分离和检测范围得到极大的改善,从而增加了系统的应用范围。     

工业气相色谱的模拟蒸馏技术在汽油馏程分析中的应用

气相色谱的模拟蒸馏技术要点是 :采样量少 ;程序升温 ;毛细管柱分离样品 ;得出样品各组分保留时间与沸点的校准曲线 ,符合ASTM D2 887 72T标准。将该标准转化为GB 2 2 5 77的标准 ,应用于汽油的馏程分析。     

气相色谱法测定1,2,4-三甲基苯纯度及其烃类杂质的研究

本工作采用气相色谱仪,从色谱典型操作条件的确定、测量结果准确度和精密度的确认对测定1,2,4-三甲基苯纯度及其烃类杂质进行研究。方法推荐键合/交联聚乙二醇玻璃毛细管色谱柱,使用氢离子化(FID)检测器,柱温采用分阶的升温程序     

Monolithic capillary columns for analysis of permanent gases and light hydrocarbons

Monolithic capillary columns based on divinylbenzene and ethylene glycol bis(acrylate) polymers were applied toward the analysis of permanent gases and light C₁-C₂ hydrocarbons by gas chromatography. It was shown that columns on the basis of the ethylene glycol bis(acrylate) polymer demonstrate better separating ability and make it possible to separate all components of the standard mixture at room temperature except the N₂/O₂ pair. The columns on the basis of divinylbenzene exhibit lower selectivity but make it possible to perform rapid analysis of the standard mixture with an analysis time less than 2 min.     

Permeability of C<Subscript>1</Subscript>–C<Subscript>3</Subscript> hydrocarbons through MDK membranes under nonisothermal conditions at lower temperatures

The presented nonisothermal technique for investigation of membrane gas separation (using MDK-1 membrane as an example) demonstrates possibilities of rapid assessment of the separation power of commercial membranes for both individual components and various mixtures in the temperature range of?20 to +40°C. The efficiency of the membrane process under these conditions (cross-flow membrane module model) for separation of propane–methane mixtures has been evaluated. It has been shown that the permeability of methane decreases with a decrease in temperature in the Arrhenius coordinates and the propane permeability increases. The separation selectivity in the mixture decreases by more than twofold in comparison with the ideal selectivity. Nevertheless, a significant improvement of separation has been observed at lower temperatures, with the recovery of the desired product and its purity being variable in a wide range depending on the practical goal. The nonisothermal technique is supposed to be useful for rapid selection of conditions (temperature, pressure, components to be separated) for efficient application of polymeric membranes for separation of hydrocarbon-containing mixtures that are close in composition to real gas sources.     

工业糠醛气相色谱分析方法的改进

用GB／T1926．2—88方法分析测试工业糠醛含量时，存在色谱柱分离效率较低，柱温高易造成组分裂解，定性和定量误差较大等问题，采用蒸馏切取窄馏分，并用双柱、多柱以及气相色谱-质谱联用定性技术，同时使用键合型中等极性毛细管柱，使工业糠醛中的各组分得到满意的分离，保证了定性的可靠性，共计定性出17种组分；保证了定量的准确性，糠醛的相对标准偏差为0．05％，回收率为89．6％～95．2％。     

轻烃组分在Al2O3色谱柱的不可逆吸附研究

研究了Al2O3/KCl,Al2O3/S,Al2O3/M 3种Al2O3毛细管色谱柱对轻烃组分分析的不可逆吸附行为,定量考察了柱温、载气流速、进样量等对C3~C4烃类组分在不同类型Al2O3色谱柱上不可逆吸附的影响。结果表明：不同类型Al2O3毛细管色谱柱对轻烃组分的不可逆吸附存在明显差异,烷烃和单烯烃的不可逆吸附现象不明显,炔烃和二烯烃等极性较强的组分存在一定程度的不可逆吸附,其中丙二烯、1,2-丁二烯和丙炔等组分在S型与M型Al2O3色谱柱上的不可逆吸附最为显著。温度和载气流速影响不可逆吸附的程度,进样量对不可逆吸附没有明显的影响。不可逆吸附导致部分炔烃和二烯烃组分测定的相对质量校正因子高于理论值,对这些组分的定量造成影响,采用校正面积归一法定量有利于提高分析结果的准确性。     

毛细柱气相色谱—傅里叶变换红外联用技术及其应用研究

考察了光管温度和尾吹等因素对气相色谱－傅里叶变换红外光谱联机检测的影响，以烷基酚混合物为分析样品，得出了ＧＣ／ＦＴＩＲ操作的最佳条件。光管温度越低，强度越高，噪以降停样品组成不太复杂时，用中粗毛细柱，载气流量在２ｍｌ／ｍｉｎ左右时。可不加尾吹。     

新型气相色谱固定相十二烷基苯磺酸锌的研究

制备了以十二烷基苯磺酸锌作为固定相的填充柱及其毛细管柱 ,并对它们的柱性能和分离能力进行了研究。试验表明 ,用十二烷基苯磺酸锌作为色谱固定相的填充柱对烷烃、芳烃、酯类、酮类有较好的分离能力 ;而用十二烷基苯磺酸锌作为固定相的毛细管柱对强极性物质 ,如羧酸、芳香酸、醇、酚等有较好的分离能力     

Hybrid Gas Separation Membranes Containing Star-Shaped Polystyrene with the Fullerene (C<Subscript>60</Subscript>) Core

A physicochemical study of novel hybrid polymer membranes based on polyphenylene oxide with a star-shaped modifier incorporated into the matrix has been conducted, and the transport properties of the membranes in the gas separation process have been studied. Poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) has been selected as the polymer matrix because of the low cost and high mechanical strength of this material. Star-shaped macromolecules (up to 5 wt %) containing six polystyrene arms grafted onto a fullerene(C₆₀) central core have been used as the filler. The structure and physical properties of the resulting membranes have been characterized by scanning electron microscopy, membrane density measurements, differential scanning calorimetry, and thermogravimetric analysis. Film surface has been studied by contact angle measurements. The gas separation properties of the membranes have been studied by the barometric method for the following individual gases: H₂, O₂, N₂, and CH₄. Data on the separation properties have been plotted as a Robeson diagram to compare with published data. It has been shown that the incorporation of star-shaped polystyrene into the PPO matrix leads to an improvement of the separation efficiency for selected gas pairs and an increase in selectivity compared with that of the unmodified membrane.     

高含硫天然气脱水工艺技术研讨

根据中国石油天然气集团公司和中国石油天然气股份有限公司立项开展的《高含硫化氢天然气田勘探开发安全生产配套技术研究——含硫气田天然气集输工艺技术专题研究》成果,结合罗家寨高酸性气田开发中三甘醇、低温分离、分子筛脱水三种工艺技术方案进行专项论证。介绍了高含硫天然气脱水工艺的特点及解决的主要关键技术难题。所推荐的分子筛脱水工艺技术已经成功应用在工程建设中,可为类似高酸性气田的开发建设提供借鉴。     

苯酚中有机杂质含量的测定

采用毛细管气相色谱内标法测定苯酚中的有机杂质,通过用不同极性的两根毛细管柱作比较,不同的分析要求可以采用不同的毛细管柱,对苯酚的生产和用户的质量控制具有一定的指导作用,为制定企业标准苯酚中有机杂质指标提供一定的理论依据。     

High purification of gases by the hybrid gas hydrate-membrane method

A combination of membrane separation with gas hydrate crystallization has been proposed for enhancing the efficiency of separation and purification of gass. A mathematical model of a hybrid gas hydrate-membrane method has been derived. The results of calculation of the degree of separation by this method for different process conditions are presented. It has been shown that the use of gas hydrate crystallization in membrane technology can preclude the concentration of impurities in the high-pressure compartment of a membrane element and thereby significantly improve the gas separation and purification efficiency.     

Investigating the Effect of Capillary Number on Performance Prediction of an Iranian Fractured Gas Condensate Reservoir

Abstract

Gas condensate reservoirs are one of the most complicated reservoirs in which the special thermodynamic behavior of reservoir fluid leads to condensate buildup instead of gas expansion, when the reservoir pressure drops below dew point pressure. To justify the phase behavior of such reservoirs, several models have been proposed. One of the models is a capillary number model that has a considerable effect on the shape of relative permeability curves. Taking account of capillary number is shown to improve the performance prediction of gas condensate reservoirs that otherwise is poorly predicted. In pressures below dew point pressure, velocity and surface tension between gas and oil increases more rapidly in the vicinity of the well compared with other parts of the reservoir, which results in condensate saturation reduction and gas relative permeability improvement. The authors model a fractured gas condensate reservoir with and without taking capillary number into consideration; the performance prediction results are compared to the actual results. The model with capillary number included is shown to be able to predict the performance with a greater accuracy than the case without capillary number.     

Total Reflux Operating Mode of Apparatuses of a Membrane Column Type during High Purification of Gases to Remove a Highly Permeable Impurity

Performance of a three-module membrane column in high gas purification processes to remove highly permeable impurities has been experimentally evaluated using the separation of the CH₄/CO₂ binary gas mixture (CO₂ content of 1 vol %) as an example. The time to reach the steady-state regime in a total reflux operating mode has been determined for two configurations, the three-module membrane column (TMC) and the continuous membrane column (CMC) proposed by Hwang with colleagues. The influence of the efficiency of removal of the highly permeable impurity on the degree of purification of the low-permeability target component has been shown. The obtained product purity has appeared to be 99.997 or 99.93% at the recovery rate of 15 or 81%, respectively. It has been demonstrated that the three-module membrane column hold promise for use in high gas purification.     

控制冷凝法对烟气中三氧化硫冷凝分离效率研究

目的研究不同操作参数和烟气工况对控制冷凝法分离烟气中SO₃效率的影响,以避免因烟气中SO₃质量浓度过高导致装置腐蚀穿孔并产生高盐污水。 方法利用自主研发的烟气中SO₃控制冷凝效率评价装置研究了不同操作参数和烟气工况对烟气中SO₃冷凝分离效率的影响。 结果烟气流量和烟气中SO₃质量浓度变化对SO₃冷凝分离效率有明显影响,冷凝系统末端引入石英过滤棉可以明显地消除烟气中SO₃质量浓度变化对SO₃冷凝分离效率的影响。在烟气取样管路的温度高于酸雾露点并且冷凝管温度介于酸雾露点和水蒸气露点之间时,烟气取样管路保温温度、冷凝管温度变化对烟气中SO₃冷凝分离效率几乎没有影响。烟气中SO₂质量浓度变化对烟气中SO₃冷凝分离效率几乎没有影响。 结论建立的SO₃冷凝分离方法对烟气中SO₃的分离效率大于95%。 