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1.
Selective refining of heavy vacuum gas oil and a combined fraction of light and heavy vacuum gas oils to remove aromatic and organoelement compounds and heavy metals by five-step countercurrent extraction with N-methylpyrrolidone or dimethylacetamide in the presence of heptane containing 1 wt % toluene was studied.  相似文献   

2.
Russian Journal of General Chemistry - Changes in the chemical composition of the vacuum gas oil in a mixture with heavy coker gas oil in the presence of industrial and laboratory...  相似文献   

3.
A raffinate meeting the requirements for the hydraulic oil body was obtained from the 225-290°C fraction of low-paraffinicity oil by extraction refining with aqueous methyl Cellosolve in the presence of pentane.  相似文献   

4.
A raffinate meeting the requirements for the transformer oil body was obtained from the 300-350°C fraction of low-paraffinicity oil by five-step countercurrent extraction of aromatic hydrocarbons and organoelement compounds with aqueous methyl Cellosolve in the presence of pentane.  相似文献   

5.
Russian Journal of Applied Chemistry - The results of one-step extraction treatment of delayed coker heavy gas oil from the Gazpromneft–Omsk Oil Refinery to remove sulfur- and...  相似文献   

6.
This communication reports the beneficial effects of co-gasification of biomass and residual oil to produce syngas. In this regard, various blends of glucose (a biomass surrogate) to vacuum gas oil (VGO) have been employed to investigate the synergic effects on the gasification process. The non-isothermal co-gasification experiments were conducted in a thermogravimetric analyzer at different heating rates and gasifying agents. The analysis showed that the co-gasification rate increased with the increase of glucose content in the feedstock. The presence of the oxygen in the biomass molecules helped the overall gasification process. The maximum gasification rate of 42.70 wt/min (DTGmax) was observed with 25 wt% glucose containing sample. The use of gasifying agents appeared to have some influence, especially during high temperature gasification of the glucose-VGO blends. At a same gasification temperature, the co-gasification rate of glucose-VGO blends were found to be 125.7 wt/min and 98.59 wt%/min for N2 and CO2, respectively. The kinetics of the co-gasification of glucose-VGO blends was conducted based on modified random pore model using TGA experimental data and implemented in MATLAB. The estimated activation energy and rate constants were found to be consistent to the observed co-gasification rates. The apparent activation energies of co-gasification of VGO/biomass blends with different weight percentages shows values ranging 60.56–48.25 kJ/mol. The kinetics analysis suggested that the addition of biomass helped to increase the reaction rate by lowering the activation energy required for accomplishing the reactions compared with petroleum carbonaceous feedstocks. The reaction rate constants isotherms are plotted to show that the k-values are exhibiting similar trends at moderate heating rates between 20 and 60 °C/min. This remark arises due to the nature of the reactions involved which are considered to be inherently similar in this range of heating rate.  相似文献   

7.
Russian Journal of Applied Chemistry - The MPF-NiMoS catalyst prepared in situ by decomposition of the thio salt [N(n-Bu)4]2[Ni(MoS4)2] in pores of an ordered mesoporous phenol-formaldehyde polymer...  相似文献   

8.
生姜挥发油的提取及其化学成分的气相色谱-质谱分析   总被引:9,自引:0,他引:9  
本文对生姜挥发油的提取先采用水蒸气蒸馏法,然后对馏出液用已醚萃取,得到提取物Ⅰ,经GC/MS检测鉴定出40种化合物。对乙醚萃取后的馏出液选用乙酸乙酯进一步提取,用GC/MS检测还鉴定出28种化合物,提取出的挥发油重量占总油量39%。  相似文献   

9.
微波辅助提取GC-MS分析莪术挥发油成分   总被引:3,自引:0,他引:3  
1引言 莪术是我国传统中药材,是一种有效的抗癌中药,在防治恶性肿瘤特别是早期宫颈癌方面有较好的疗效.据<本草纲目>记载:莪术辛、苦、温,归肝、脾经,具有行气破血、消积止痛之功效,被称为血中之气药.莪术根茎中含挥发油约1%~2.5%,为多种倍半萜类,其中莪术醇和榄香烯以及莪术酮和莪术二酮具有抗肿瘤、抗病毒的疗效.微波辅助提取具有设备简单、适用范围广、萃取效率高、节省时间和溶剂、污染小等诸多优点,应用范围已从最初的环境样品分析迅速扩展到食品、化工和农业等领域.本研究以莪术为原料,采用微波萃取法提取挥发油,通过紫外分光光度法监测其含量变化,用气相色谱-质谱法(GC-MS)分析最优提取工艺条件下所得挥发油成分,为进一步开发莪术药用价值提供依据.  相似文献   

10.
Cold-pressed plant oils are of high interest to consumers due to their unique and interesting flavors. As they are usually only pressed at low temperatures and filtered, without further processing stages (as refining), they preserve their character that originates from the plant the oil was extracted from. Coriander cold pressed oil is gaining popularity as a novel product, obtained from its fruits/seeds; due to the high amount of terpenes, it has very characteristic flavor. A novel, vacuum-assisted sorbent extraction (VASE) method was used to extract terpenes from coriander cold pressed oil. Optimal parameters were determined. The profile of compounds extracted using VASE was compared with that of classic hydrodistillation method. Moreover, 17 monoterpene hydrocarbons and alcohols were identified with β-linalool as the main compound, followed by α-pinene, γ-terpinene, camphor, sylvestrene, β-pinene, and o-cymene. Differences were noted between profiles of terpenes after hydrodistillation and VASE extraction. For 8 out of 17 terpenes, VASE was used for their quantitative analysis. Regarding simplicity of the method, small sample requirement (200 mg) and short extraction time (5 min), VASE combined with GC/MS is well suited for characterization of terpenes in such matrix as plant oils.  相似文献   

11.
利用核磁共振氢谱测定了重柴油中芳烃抽提流程各控制点的组分,绘制了油/N-甲基吡咯烷酮(NMP) 和水/NMP体系的标准曲线,发现由此可以计算油品的组成。结果表明,该法可用于生产工艺控制流程中。最后对 溶剂的循环利用作出了评价。  相似文献   

12.
采用气相色谱-原子发射光谱检测器(GC-AED),建立了同时测定减压馏分油(初馏~523℃)中碳、硫收率随沸点变化的色谱模拟蒸馏分析方法.优化了减压馏分油模拟蒸馏的色谱条件和光谱条件.以C5~C40正构烷烃为试样,建立了正构烷烃的沸点与保留时间的校正曲线,进而得到硫色谱图的保留时间与沸点之间的校正曲线.扣除空白实验下碳、硫的基线后,采用自行研制的切片积分软件,得到减压馏分油中碳、硫的收率随沸点变化的关系曲线,并将碳的模拟蒸馏计算结果与ASTMD2887标准方法进行了对比,结果具有较好的一致性.已将该方法用于催化裂化原料中碳、硫分布随沸点变化的研究中.  相似文献   

13.
轻质油品非加氢脱硫技术*   总被引:5,自引:0,他引:5  
日益严格的环保法规,对生产低硫、超低硫清洁油品技术提出了更高的要求。传统的加氢脱硫技术存在投资大、运行成本高等问题,因此开发成本低、操作条件温和的非加氢脱硫技术成为一种趋势。本文综述了目前轻质油品非加氢脱硫的相关技术,主要包括氧化脱硫、吸附脱硫和生物脱硫等技术的研究进展;简要介绍了萃取脱硫、络合脱硫、催化裂化脱硫、烷基化脱硫、膜分离脱硫及离子液体脱硫等技术;同时对轻质油品非加氢脱硫技术的应用前景进行了展望。  相似文献   

14.
微波辅助提取-气相色谱质谱联用测定肉桂中的挥发油   总被引:1,自引:0,他引:1  
利用非极性溶剂微波辅助提取(NPSMAE)-气相色谱质谱联用研究了肉桂中的挥发油成分, 并测定了挥发油中的主要成分肉桂醛(Cinnamaldehyde)的含量. 考察了NPSMAE提取溶剂的种类、提取温度、提取时间及固液比等对测定的影响, 同时将NPSMAE与超声波辅助提取(UAE)及水蒸气蒸馏(HD)等方法进行了比较. 结果表明, 与常规提取方法相比, NPSMAE具有提取时间短、提取产率高等优点, 是一种实用的中药挥发油提取方法.  相似文献   

15.
研究采用气质联用测定了超临界CO2萃取的艾叶挥发油的主要成分。实验以挥发油中含量较高的石竹烯氧化物(12.01%)为标准物,以二甲亚砜为内标,采用气相色谱程序升温的方法对艾叶油微胶囊进行石竹烯氧化物含量测定。二甲亚砜和石竹烯氧化物的出峰时间分别为4.75和14.68min,且与其它组分完全分离,空白微胶囊在两者对应出峰位置处无干扰;线性范围为1.2~19.2mg/L;精密度、重现性和回收率均符合分析的要求。艾叶油微胶囊的平均包封率为97.6%。结果表明:所建方法可靠、准确、稳定,可用于艾叶挥发油微胶囊包封率的测定来控制微胶囊质量。  相似文献   

16.
One Hundred Fifty-Seven nm photodissociation of singly protonated peptides generates unusual distributions of fragment ions. When the charge is localized at the C-terminus of the peptide, spectra are dominated by x-, v-, and w-type fragments. When it is sequestered at the N-terminus, a- and d-type ions are overwhelmingly abundant. Evidence is presented suggesting that the fragmentation occurs via photolytic radical cleavage of the peptide backbone at the bond between the alpha- and carbonyl-carbons followed by radical elimination to form the observed daughter ions.  相似文献   

17.
Russian Journal of Applied Chemistry - The main problems of the development of heavy oil fields and the ways of their solution are considered. The modern nontraditional methods for extracting heavy...  相似文献   

18.
The Fischer–Tropsch heavy fraction is a potential feedstock for transport-fuels production through co-processing with fossil fuel fraction. However, there is still the need of developing new and green catalytic materials able to process this feedstock into valuable outputs. The present work studies the co-hydrocracking of the Fisher–Tropsch heavy fraction (FT-res.) with vacuum gas oil (VGO) at different ratios (FT-res. 9:1 VGO, FT-res. 7:3 VGO, and FT-res. 5:5 VGO) using phonolite-based catalysts (5Ni10W/Ph, 5Ni10Mo/Ph, and 5Co10Mo/Ph), paying attention to the overall conversion, yield, and selectivity of the products and properties. The co-processing experiments were carried out in an autoclave reactor at 450 °C, under 50 bars for 1 and 2 h. The phonolite-based catalysts were active in the hydrocracking of FT-res.:VGO mixtures, presenting different yields to gasoline, diesel, and jet fuel fractions, depending on the time of reaction and type of catalyst. Our results enable us to define the most suitable metal transition composition for the phonolite-based support as a hydrocracking catalyst.  相似文献   

19.
本文采用多柱自动切换气相色谱仪和真空全脱气装置对变压器和互感器用油中的气体进行了系统的分析,除可测定油中的氢、甲烷、乙炔、乙烯、乙烷、二氧化碳和一氧化碳等气体外,还可根据不同需要测定氮、氧以及C3和C4烃的含量。本方法已用于诊断变压器和互感器内部变化及故障。  相似文献   

20.
A method based on dynamic headspace vacuum transfer in trap extraction, followed by gas chromatography coupled with a mass spectrometer (DHS-VTT-GC-MS), was validated for the fast quantitation of 1,4-dichlorobenzene (p-dichlorobenzene; PDCB) and thymol residues in beeswax. The quantitation limits (LOQ) were 0.05 mg/kg (PDCB) and 0.25 mg/kg (thymol). Recoveries above 80% were obtained for PDCB concentrations between 0.05 and 10 mg/kg and for thymol concentrations between 0.25 and 200 mg/kg. Analysis of beeswax samples showed a good correlation between the results obtained by DHS-VTT-GC-MS analysis and those of a previous method based on SPE extraction followed by gas chromatography and triple- quadrupole mass spectrometry (GC-MS/MS) (R2 = 0.9770 for PDCB and 0.9666 for thymol). However, the sample preparation and chromatography were much shorter using the DHS-VTT-GC-MS method. Forty comb foundations samples produced in Switzerland in 2019 and 2021 were analysed using DHS-VTT-GC-MS. Fourteen samples contained PDCB above the LOQ of 0.05 mg/kg, ranging up to a maximum of 1.53 mg/kg. The mean concentration of the positive samples was 0.22 mg/kg. All samples contained thymol residues ranging between 3.9 and 84.4 mg/kg with mean and median concentrations of 22.7 mg/kg and 17.4 mg/kg. Residue levels of PCDB and thymol in Swiss beeswax were substantially below those measured 20 (PDCB) and 10 (thymol) years ago, respectively.  相似文献   

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