SOLUBILITY STUDIES OF PARAFFIN WAXES IN SELECTED PETROLEUM FRACTIONS AND TOLUENE

Solubility studies of paraffin waxes with melting point range of 43^°C to 57^°C in two undefined petroleum fractions and Toluene have been carried out. An Attempt was made to develop a correlation for predicting the solubility of the waxes in these solvents. The one parameter ideal solubility law expression has been successfully used to represent the experimental data.     

CHARACTERISATION OF PARAFFIN WAXES BY DSC AND HIGH TEMPERATURE GC

ABSTRACT

Paraffin waxes of different crude oil sources were characterised using Differential Scanning Calorimetry, and High Temperature Capillary GC techniques. The carbon number distribution of the waxes were determined by calibrating the GC with standard n-paraffins blend. The δH_s?s transition obtained in DSC. thermogram of the waxes were correlated with its normal paraffin content. This correlation was further validated by obtaining n-paraffins content through High Temperature GC technique.     

CHARACTERISATION OF PARAFFIN WAXES BY DSC AND HIGH TEMPERATURE GC

Paraffin waxes of different crude oil sources were characterised using Differential Scanning Calorimetry, and High Temperature Capillary GC techniques. The carbon number distribution of the waxes were determined by calibrating the GC with standard n-paraffins blend. The δH_s-s transition obtained in DSC. thermogram of the waxes were correlated with its normal paraffin content. This correlation was further validated by obtaining n-paraffins content through High Temperature GC technique.     

石油馏分及产品中元素硫的示波极谱测定

提出了采用示波极谱法测定馏分油及石油产品元素硫的方法,支持电解液是含有０．５ｍｏｌ／Ｌ醋酸和０．３ｍｏｌ／Ｌ醋酸铵体按比为１：１的甲苯－甲醇溶液。在此介质中,饱和甘汞电极的峰电位为－０．６１Ｖ。该方法灵敏度高,当元素硫浓度为０．１ｍｇ／Ｌ,时仍可以看到明显峰电流;精密度和准确度较好,对１ｍｇ／Ｌ元素硫的测定,标准偏差为０．０２;元素硫浓度在０￣４ｍｇ／Ｌ浓度范围与极谱峰电极呈线性关系。     

石油馏分的假组分处理方法

本文提出了一种从馏分恩氏蒸馏数据和总体密度对石油度馏分进行假组分切割和物性估算的方法。该方法用显式关联直接将恩氏蒸馏转换成实沸点蒸馏数据和计算出馏分斩中平均沸石，然后用积分法切割假组分。文中给出了数值计算步骤和例题。     

氢气在石油馏分中溶解度的测定

在温度为２２～２５０℃和压力为２～ １２ ＭＰａ条件下,测定了氢气在甲苯、正庚烷、汽油、柴油、蜡油和常压渣油馏分中的溶解度。结果表明,氢气在甲苯、正庚烷和石油馏分中的溶解度随温度和压力的提高而增加,也随馏分沸点的上升而增加,但氢气在常压渣油中的溶解度小于在蜡油和柴油中的溶解度。     

石油重馏分油临界性质预测方法的研究

重馏分油在达到其临界点前已发生热分解，因而不能测得其临界性质（临界温度和临界压力），经研究提出预测重馏分油临界性质的一种方法。选用监界温度高于６９１．８５Ｋ的已知的临界性质的８个纯烃，分别与苯配成不同组成的二元混合物，用半封闭管法测定混合物的监界性质，将此混合物与苯的临界性质和苯在混合物中的含量等数据，经数学处理得到纯烃临界性质的方法计算值的方法。将重馏分油视为虚拟发掺入苯，测定该混合物临界性质，     

石油磺酸盐中极性组分的协同效应

采用硅胶柱层析法将两种石油磺酸盐分别分离成不同极性组分,在加醇和无醇条件下考察了石油磺酸盐不同极性组分及其复配体系的相行为和超低界面张力。将不同极性组分按一定比例复配,在加醇条件下可形成中相微乳液,且可获得较高的增溶参数和超低界面张力。在无醇条件下,石油磺酸盐单独组分均不能形成中相微乳液,合理复配两种或三种不同极性组分,不但可以形成中相微乳液且可获得较高的增溶参数和超低界面张力,相行为参数随复配比例的变化而变化。在上述实验的基础上提出石油磺酸盐是由不同极性组分组成的复杂表面活性剂,其不同极性组分间存在协同效应,极性在协同效应中起着重要作用。建议根据不同极性组成比例来监控石油磺酸盐产品质量。     

CRYSTALLINITY AND AVERAGE CARBON NUMBER OF PETROLEUM WAXES BY X-RAY DIFFRACTION

ABSTRACT

Crystallinity and average carbon number of different petroleum waxes have been determined by means of X-ray diffraction. The effect of oil and polymers, viz, polyethylene (PE) and ethylene vinyl acetate (EVA) co-polymer on the crystallinity and average carbon number of petroleum waxes have also been studied. Crystallinity data has been correlated with composition and properties of the waxes.     

石油磺酸盐组分的结构与性能关系

 以绥中低凝环烷基馏分油为原料, 以三氧化硫为磺化剂, 在单管降膜式磺化反应器中合成了石油磺酸盐NPS. 采用溶剂萃取法将NPS按平均相对分子质量的不同分离为若干组分, 采用元素分析、¹H-NMR及¹³C-NMR表征各组分的分子结构, 并测定了它们的界面张力、临界胶束浓度(CMC)和在孤岛地层砂上的吸附量. 采用室内模拟驱油实验考察了NPS各组分的驱油性能. 结果表明, NPS的界面化学性质与其分子结构密切相关. NPS浓度在CMC左右, 其吸附量达到最大值; NPS各组分的界面活性和吸附性质有较大差异. NPS各组分的驱油效率不同, NPS与Na₂CO₃、NaOH、NaCl及Na₂SO₄等电解质复配后, 油-水界面张力降低, 驱油效率大大增加.     

CRYSTALLINITY AND AVERAGE CARBON NUMBER OF PETROLEUM WAXES BY X-RAY DIFFRACTION

Crystallinity and average carbon number of different petroleum waxes have been determined by means of X-ray diffraction. The effect of oil and polymers, viz, polyethylene (PE) and ethylene vinyl acetate (EVA) co-polymer on the crystallinity and average carbon number of petroleum waxes have also been studied. Crystallinity data has been correlated with composition and properties of the waxes.     

海洋石油管线结蜡规律的实验研究

在石油生产和集输的过程中,由于降温作用,石蜡从原油中淅出,并附着在设备和管道内部,限制流量,因而造成产能损失。尤其是在深海采油过程中,降温作用剧烈,结蜡的危害更加严重。结蜡的机理是温差作用下的分子扩散。世界范围内最普遍的清蜡办法是使用清蜡器（清蜡球）,而清蜡频率的确定还是处在摸索阶段。为了优化清蜡频率,准确预测结蜡的速度是必要的。在项目中,利用一台新型设备对一现场的原油进行了结蜡速度的测试。实验结果表明,对于不同尺寸的管道,在既定的温度条件下,该原油流速相同,则结蜡速度相同;而增大剪切力可降低结蜡速度。     

土壤中分段石油烃热脱附行为研究

采用管式炉模拟土壤中石油烃热脱附过程,考察了加热温度、保持时间以及负压条件对土壤中分段石油烃热脱附过程的影响,为实际石油烃污染土壤修复工作提供理论依据。结果表明：提高加热温度、延长保持时间以及提供负压条件均对提高土壤中总石油烃去除率产生积极作用;常压下,在250℃保持2 h与300℃保持1 h的条件下,土壤中总石油烃去除率均达到97%以上,总石油烃残留量低于GB 36600—2018《土壤环境质量建设用地土壤污染风险管控标准》中第一类用地风险筛选值;当温度为150℃时,土壤中C₁₀～C₁₆,C₁₇～C₂₈,C₂₉～C₄₀段石油烃组分在1 h内的去除率均低于40%;当温度高于250℃时,土壤中C₁₀～C₁₆和C₁₇～C₂₈段的石油烃组分可被快速有效去除;C₂₉～C₄₀段石油烃组分受加热温度和保持时间变化影响明显,因此提高重质石油...     

COMPOSITIONAL ANALYSIS OF PETROLEUM WAXES BY ZEOLITE MOLECULAR SIEVE-GCMS

ABSTRACT

To investigate the composition of petroleum waxes, studies were carried out on the extraction of normal paraffins from petroleum waxes by zeolite molecular sieve type 5A. Time required for adsorption of different molecular weight n-paraffins from standard mixture and petroleum waxes has been ascertained. Un-adsorbed part of the waxes has been investigated by GC-MS technique. Recovery of adsorbed hydrocarbon from molecular sieve was done by supercritical fluid extraction.     

PHASE TRANSITIONS IN PETROLEUM WAXES DETERMINED BY INFRARED SPECTROSCOPY

In the present paper attempts have been made to study the phase transition temperatures in petroleum waxes by infrared spectroscopy and the resulting data were correlated with phase transition temperatures obtained by differential scanning calorimetry (DSC).     

CATALYTIC CRACKING OF RESIDUAL PETROLEUM FRACTIONS

Arabian Light crude oil vacuum bottoms has been fractionated into five high-boiling fractions by wiped film evaporation, and the fractions subjected to catalytic cracking in a fixed-fluidized bed using a commercial equilibrium cracking catalyst. Density, aromaticity, and heteroatom content generally increased with boiling point, as did metals content except for vanadium and iron which demonstrated possible bimodal distributions. The cracking response of these fractions showed increasing yields of dry gas and coke, with decreasing gasoline yields, as a function of increasing apparent boiling point as would normally be expected. Surprisingly, however, local maxima were observed for wet gas yield and total conversion, with local minima for cycle oil and slurry yields, in the region of the 1200-1263°F (650-680°C) middle fraction. All fractions showed significant response to cracking, with coke yields generally being the only negative factor observed.     

COMPOSITIONAL ANALYSIS OF PETROLEUM WAXES BY ZEOLITE MOLECULAR SIEVE-GCMS

To investigate the composition of petroleum waxes, studies were carried out on the extraction of normal paraffins from petroleum waxes by zeolite molecular sieve type 5A. Time required for adsorption of different molecular weight n-paraffins from standard mixture and petroleum waxes has been ascertained. Un-adsorbed part of the waxes has been investigated by GC-MS technique. Recovery of adsorbed hydrocarbon from molecular sieve was done by supercritical fluid extraction.     

CATALYTIC CRACKING OF RESIDUAL PETROLEUM FRACTIONS

ABSTRACT

Arabian Light crude oil vacuum bottoms has been fractionated into five high-boiling fractions by wiped film evaporation, and the fractions subjected to catalytic cracking in a fixed-fluidized bed using a commercial equilibrium cracking catalyst. Density, aromaticity, and heteroatom content generally increased with boiling point, as did metals content except for vanadium and iron which demonstrated possible bimodal distributions. The cracking response of these fractions showed increasing yields of dry gas and coke, with decreasing gasoline yields, as a function of increasing apparent boiling point as would normally be expected. Surprisingly, however, local maxima were observed for wet gas yield and total conversion, with local minima for cycle oil and slurry yields, in the region of the 1200–1263°F (650–680°C) middle fraction. All fractions showed significant response to cracking, with coke yields generally being the only negative factor observed.     

CHARACTERIZATION OP VANADIUM COMPOUNDS IN SELECTED CRUDES II. ELECTRON PARAMAGNETIC RESONANCE STUDIES OP THE FIRST COORDINATION SPHERES IN PORPHYRIN AND NON-PORPHYRIN FRACTIONS

We applied electron paramagnetic resonance spectroscopy (EPR) to heavy petroleum fractions to characterize the first coordination sphere around the vanadyl +2 ion. The fractions were generated using a modified porphyrin extraction procedure. For the residual oil from the extraction, which contains the non-porphyrin metals, the first coordination sphere was dominated by 4N and N O 2S for Boscan, Beta, Morichal, and Arabian Heavy crudes. Maya had distinctively different parameters.

These findings are significant for determining the overall structure of metal-containing compounds in heavy crude oils. We discuss the difference between the porphyrin and non-porphyrin behavior, possible blogenic precursors, and some process implications.     

CHARACTERIZATION OP VANADIUM COMPOUNDS IN SELECTED CRUDES II. ELECTRON PARAMAGNETIC RESONANCE STUDIES OP THE FIRST COORDINATION SPHERES IN PORPHYRIN AND NON-PORPHYRIN FRACTIONS

ABSTRACT

We applied electron paramagnetic resonance spectroscopy (EPR) to heavy petroleum fractions to characterize the first coordination sphere around the vanadyl +2 ion. The fractions were generated using a modified porphyrin extraction procedure. For the residual oil from the extraction, which contains the non-porphyrin metals, the first coordination sphere was dominated by 4N and N O 2S for Boscan, Beta, Morichal, and Arabian Heavy crudes. Maya had distinctively different parameters.

These findings are significant for determining the overall structure of metal-containing compounds in heavy crude oils. We discuss the difference between the porphyrin and non-porphyrin behavior, possible blogenic precursors, and some process implications.