Characterization of Functional Groups of Asphaltenes in Vacuum Residues Using Molecular Modelling and FTIR Techniques

Asphaltenes are components of crude oil, and their average chemical structures are characterized with difficulty. This study shows that simple Fourier transform infrared (FTIR) analysis spectroscopy could be adapted to the determination of aromatic hydrogens in asphaltenes and resins and elucidation of their average molecules. The work demonstrates the existence of a linear correlation in the infrared (IR) intensities of the symmetric and asymmetric aromatic hydrogens in methyl substituted arenes, in the 2,900 to 3,100 cm^-1 region and of the out-of-plane deformation in the 700 to 900 cm^-1 region.     

傅里叶变换红外光谱技术在润滑油监测中的应用综述

傅里叶变换红外光谱技术是油液监测体系中一项重要的技术手段,傅里叶红外光谱技术可以追踪润滑油中化学官能团变化,使得对润滑油的整体质量评估更加完善和准确,从而为是否换油或采取其他措施提供参考。傅里叶红外光谱能够提供积炭、水分、乙二醇、氧化程度、硝化程度、添加剂含量等重要信息,这些信息正是新油逐渐劣化的重要指标;从检测效率来看,目前红外光谱最快的检测速度达到120个样品/小时,完全可以满足大型工矿企业数目众多的设备油液监测需求;定量红外光谱技术已经开发出多种与油样状态相关的多种方法,能够确定油样中的酸、碱及水分等含量。在油品分析中心实验室,这些方法避免了ASTM滴定方法程序的繁杂,扩展了红外光谱技术的总体适用性。论文对基于红外光谱技术的状态监测进行了综述,对该技术已经取得的成绩、未来的发展方向进行了总结,并以加强红外在润滑油分析方面的应用为目的,讨论了最新的定量红外光谱技术、红外光谱存在的问题等内容。     

大港减渣超临界萃取物的FTIR分析

通过大量的溶剂选择性实验,选取对大港减渣的16个超临界萃取物都具有优异溶解性能的环己烷为良性溶剂,并对每个萃取物分别进行KTIR分析,探索大港减渣所含基团的规律性。分析结果表明,不同大港减渣超临界萃取物的红外光谱图有一定的类似性,说明其含有的基团接近;大港减渣超临界萃取物含有10余种官能团,其中烷烃的含量最大;不同萃取物中同一种基团的含量不同。     

Classification of petroleum origin and integrity by FTIR

A method was developed for classifying petroleum into four types according to their origin and integrity: marine, non-marine, degraded and thermally transformed. The method was based on the relative proportions of functional groups measured by FTIR spectroscopy. Twenty-one petroleum samples were used for model calibration and six for validation, which were pre-classified. Aliphatic functional group absorption maxima were used at 2919, 2856, 1457 and 1376 cm^?1, as well as at 1700  and 811 cm^?1 for aromatic groups, and at 1152 and 1030 cm^?1 for polar groups (sulphonyl and ether, respectively). Using hierarchical cluster and discriminate analyses, three canonic functions were obtained that classified the samples according to their origin and integrity, with a prediction efficiency of 100%, for both calibration and validation. The canonic functions derived from the discriminate analysis had correlation coefficients of 0.994, 0.900, and 0.867, among the variables studied and the classification factor. The method is efficient for the proposed classifications and can be useful for a range of applications.     

Transesterification Reaction of Waste Cooking Oil and Chicken Fat by Homogeneous Catalysis

In the last years, biodiesel production has been on a steady increase due to it is renewable and biodegradable fuel. The process to obtain biodiesel can be carried out using different raw materials. It is conlmonly performed by transesterification reaction of vegetable oils with methanol and using a homogeneous or heterogeneous catalyst. This work seeks to compare the results produced in transesterification of wasted cooking oil and chicken fat by homogeneous catalysis with NaOH. Due to in each case triglyceride comes from different raw materials, operation conditions differ slightly, which is more evident in the values used for the temperature. For chicken fat was used temperature variations between 35 ℃ and 55 ℃, varying catalyst in percentages between 0.3% and 0.7% with a molar ratio 6：1 in all cases and a reaction time of I h. Likewise, the conditions used in the tmnsesterification process of waste cooking oil were temperature between 50 ℃ and 60 ℃ with a molar ratio 6/1 and 9/1 for alcohol and oil, and catalyst percentage between 0.5% and 0.7% by weight. The yields obtained were between 78% and 94%, or 83% and 95%, for chicken fat and wasted cooking oil, respectively.     

红外光谱测定固体酸催化剂表面酸性

利用固体酸催化剂吸附吡啶表征固体酸催化剂的性质,以测定其表面酸性部位的类型(L酸、B酸)、强度和酸量。采用抽真空系统、红外光谱(fTIR)方法,根据固体酸催化剂红外光谱的峰面积计算B酸、L酸的含量。     

FTIR法测定含氰废气中的氮氧化物

建立了一种通过FTIR测定含氰废气中氮氧化物的方法,采用经典最小二乘法建立了含氰废气中氮氧化物的定量分析模型,优化了方法的分析条件,考察了方法的精密度与准确度,并对实际试样进行了分析.实验结果表明,在扫描范围650～4000 cm-1、分辨率0.5 cm-1、扫描次数64次、扫描时间为1 min条件下,各组分的相关系数...     

Stabilization Studies of Middle Distillate Fuels: Structural Composition of Insoluble by FTIR Spectroscopy

For reducing the supply-demand gap of diesel fuel, blending of cracked stocks is essential with straight run products. This enhances the instability problem. This problem can be reduced using various stabilization procedures. In the present paper blends of cracked stocks light cycle oil (LCO) with straight run gas oil (SRGO) were stabilized by methanol extraction and hydrostabilization techniques. The insoluble from these fuels as such and their blends were stabilized and characterized using FTIR spectroscopy.     

Stabilization Studies of Middle Distillate Fuels: Structural Composition of Insoluble by FTIR Spectroscopy

Abstract

For reducing the supply-demand gap of diesel fuel, blending of cracked stocks is essential with straight run products. This enhances the instability problem. This problem can be reduced using various stabilization procedures. In the present paper blends of cracked stocks light cycle oil (LCO) with straight run gas oil (SRGO) were stabilized by methanol extraction and hydrostabilization techniques. The insoluble from these fuels as such and their blends were stabilized and characterized using FTIR spectroscopy.     

GC/FTIR法和GC/MS法联合分析裂解碳五馏份的组成

在两根分离机理完全不同的色谱柱上，即ＨＰ－１０１柱（分配色谱）和Ａｌ３Ｏ２／ＫＣｌＰＬＯＴ柱（吸附色谱），对乙烯装置裂解碳五产品进行了较完全的分离，联合使用毛细管气相色谱－傅立叶红外光谱法和毛细管气相色谱－质谱法进行定性，在氢火焰离子化检测器上得到归一化的定量结果。同时，也推出了两种能分析单体烃及其二聚物组份的裂解碳五组成的色谱方法。     

固体香精组成的剖析

采用红外及色—红联用技术分析固体香精组成，用面积归一法定量，方法简便快速，重复性良好。     

聚合物驱油田采出水生化处理的表征

用GC／MS和GC／FTIR分析了聚合物驱油田采出水及其生物膜法生化处理水中可被XAD系列树脂富集的有机组分，并用超滤技术测定COD的分子量分布。结果表明：两次采集的生化处理进水的COD为102及117mg/L，其中树脂可吸附的COD分别占74．1％及74．8％；生化处理出水的COD为67．5及66．9mg/L，其中树脂可吸附的COD分别占66．4％及68．5％。生化处理进水中树脂可吸附的有机物包括脂肪烃、苯系数、多环芳烃、苯酚类化合物及未知结构的有机酸，其中未知结构有机酸的含量较高。该废水经生化处理后，残余有机物主要为未知结构的有机酸。生化处理对大分子及悬浮性COD的去除效果较好。     

磷改性斜发沸石的组成和结构表征

采用焙烧法、微波法固固相同晶取代反应对斜发沸石骨架进行磷改性 ,并用化学分析、XRD、FT -IR和2 9Si、2 7Al、3 1 PMASNMR等手段对其化学组成和骨架结构进行表征。结果表明 ,通过骨架脱Al或占据晶格空穴 ,P进入沸石骨架形成八面体硅的Si(Oct)—O—P结构及Si端位磷氧基团 ;也可以通过Si、Al、P结构重排形成Al—O—P结构。由于P的进入 ,沸石骨架扭曲 ,矿样结晶度降低 ,主衍射峰位移。但是 ,磷改性并未破坏斜发沸石的基本骨架结构 ,仍属于斜发沸石单斜晶系。由于微波对矿样有较强的穿透能力 ,微波法骨架上P的同晶取代效果优于焙烧法。     

Structural Characterization of Asphaltenes and Ethyl Acetate Insoluble Fractions of Petroleum Vacuum Residues

Asphaltenes and insoluble fractions of vacuum residues (VRs) of two Indian crude oils (viz. Heera and Jodhpur) of different specific gravity were obtained by precipitation of VRs in n-hexane, n-heptane, and ethyl acetate, and also by subsequent reprecipitation of n-heptane and ethyl acetate soluble fractions by n-pentane. The effect of various solvents on average molecular structure of asphaltenes and insolubles was studied using nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared spectroscopy (FTIR), and size exclusion chromatography (SEC). The asphaltenes and insolubles of Jodhpur VR have higher amounts of high molecular weight species with a high concentration of condensed and substituted aromatic rings, branched and/or short alkyl side chains, oxygen and nitrogen functionalities, compared to that of Heera VR. Ethyl acetate insolubles comprise a higher number of substituted aromatic structures, branched aliphatic structures, complex average unit structures, nitrogen and oxygen functionalities, and high molecular weight (MW) species as compared to hexane and heptane asphaltenes. Heptane insolubles consist of more naphthenic rings condensed with aromatic rings than C6A and EAI.     

Characterization of Pegmatoid from Dimension Stones Tailings for Application as Ceramic Raw Material

Exploitation and processing of pegmatoids at Brazil＇s northeast （Serido region-RN State） aiming further use as dimension stone produces mass losses ranging between 30%-90%. The tailings are predominantly composed by feldspar, quartz, muscovite and other Fe-bearing silicates such as biotite and amphiboles, suitable for ceramic production. The recovery of these elements depends on mica＇s remotion to levels under 2.0%, preferentially by dry methods due the scarce amount of water prevailing at Serido region. This paper presents results from pegmatite tailings characterization from Serido region showing the potentially application as raw material for ceramic production. To do it, a new technological route must be developed to fit it as main component to white ceramic industry, considering the properties required by ceramic industries.     

The Structural Characterization of Saturate,Aromatic, Resin,and Asphaltene Fractions of Batiraman Crude Oil

Abstract

The structural characterization of fractions of Batiraman crude oil, which is the heavy crude oil from a field in the southeastern part of Turkey, was investigated. Batiraman crude oil and its saturate, aromatic, resin, and asphaltene (SARA) fractions were seperated. Treatment of crude oil with n-heptane provided the separation of asphaltene. Maltene was collected by evaporating the n-heptane from the filtrate. Then, maltene was separeted into saturates, aromatics, and resins by SARA technique. Maltene was separated into saturate, aromatic, and resin fractions using column chromatography. SARA fractions were quantified on a weight percent basis. Fractions of Batiraman crude oil were characterized by elemental analysis, proton nuclear magnetic resonance (¹H NMR) analysis, electrospray ionization mass spectrometry (ESI-MS), and Fourier transform infrared (FTIR) spectroscopy techniques.     

Characterization and Drying of Green Mint

Mint is a medicinal and aromatic plant. It is very important for the pharmacopoeia, perfumes, confectionery and liquor industry. Some green mint leaves without rods are used as samples. Physical and mechanical properties of the sample such as the desorption isotherms, the density and volumetric withdrawal are determined. The kinetics of drying, where it follows the changes of the water content of the sample as a function of the drying time for the three temperatures 30, 40 and 50℃, is also presented and discussed.     

Characterization of the hard anodizing layers formed on 2014-T3 Al alloy,in sulphuric acid electrolyte containing sodium lignin sulphonate

The properties of hard anodizing layers formed on 2014 Al alloy in sulphuric acid electrolyte containing sodium lignin sulphonate were investigated. The corrosion behavior of 2014 Al alloy has been studied using potentiodynamic polarization technique. Anodic layers morphology and composition were examined by scanning electron microscope, energy dispersion X-ray (EDX), X-ray diffraction (XRD) and Fourier infrared spectroscopy (FTIR). The results showed that the corrosion resistance has been enhanced after hard anodizing of 2014 Al alloy. Addition of lignin sulphonate to the sulphuric acid electrolyte significantly improved the corrosion resistance of the anodized 2014 aluminum alloy by adsorption on copper-intermetallic phases. Adsorption of sodium lignin sulphonate on oxide surface has been confirmed by SEM, EDX, and FTIR. Phenolic and carboxylic groups in sodium lignin sulphonate are functional groups, which are responsible of complex formation on oxide surface. The morphology of the hard anodizing layer is non-homogenous due to the high copper content of 2014 Al alloy. Addition of sodium lignin sulphonate resulted in the formation of anodic layers with more homogeneity and fewer cracks.     

Rheological Properties and Composition of Some Vacuum Distillates Derived from Indian Crudes

Abstract

Three vacuum distillates boiling range 400°C–530°C derived from Bakrola, Dholka, and PY-3 crudes of Gujarat region (India) were subjected to urea adduction to isolate n-paraffin components from them. The deparaffinized base oils obtained after removal of n-paraffin components from the distillate fractions were further fractionated into various hydrocarbon-type constituents viz iso + cyclo paraffins, aromatics, and polar components by column chromatography. The influence of various hydrocarbon-type components thus separated on rheological characteristics (pour point and viscosity temperature behavior) of deparaffinized base oil was investigated. This study was done by preparing base oil blends by adding separated hydrocarbon-type constituents in various concentrations to different base oils and characterizing them. The effect of change of solvent matrix on the rheological characteristics was also determined. The study demonstrated the role of solid n-paraffins for variation in pour point and viscosity temperature behavior of the waxy distillate fractions.