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1.
The influence exerted by copolymers of the C9 fraction of liquid pyrolysis products of petroleum raw materials with maleic anhydride and by their esterification products, added to paper pulp, on the main paper properties was examined.  相似文献   

2.
The presence and absence of alkane isomers in petroleum and petroleum derivatives depend on the complexity of these structures. It was assumed that the more complex the structure is the less probable it is that that the molecule can be detected in any petroleum derivative. Complexity is a vague concept, which has not been defined in quantitative terms yet, and therefore there is no experimental method, which could be used to determine ‘complexity’. Mass spectrometry and infrared spectroscopy in combination with gas chromatography were used to identify the various structural isomers of alkanes in petroleum ether. The isomers were categorised in quantitative terms by using topological indices and linear discriminant analysis. It was found that alkanes possessing a more complex, highly branched structure are less probable to be detected in petroleum ether than isomers with a simpler backbone structure. It was proposed that the experimental ‘measure’ of the complexity of isomeri should be proportional to 1/Ci , where Ci , denotes the concentration of isomeri in a (primary) petroleum derivative.  相似文献   

3.
Recent results on the surface modification of petroleum cokes and their electrochemical properties as anodes of secondary lithium batteries are summarized. The surface of petroleum coke and those heat-treated at 1860-2800 °C were fluorinated by elemental fluorine (F2), chlorine trifluoride (ClF3) and nitrogen trifluoride (NF3). No surface fluorine was found except only one sample when ClF3 and NF3 were used as fluorinating agents while surface region of petroleum coke was fluorinated when F2 was used. Transmission electron microscopic (TEM) observation revealed that closed edge of graphitized petroleum coke was destroyed and opened by surface fluorination. Raman spectra showed that surface fluorination increased the surface disorder of petroleum cokes. Main effect of surface fluorination with F2 is the increase in the first coulombic efficiencies of petroleum cokes graphitized at 2300-2800 °C by 12.1-18.2% at 60 mA/g and by 13.3-25.8% at 150 mA/g in 1 mol/dm3 LiClO4-ethylene carbonate (EC)/diethyl carbonate (DEC) (1:1, v/v). On the other hand, main effect of the fluorination with ClF3 and NF3 is the increase in the first discharge capacities of graphitized petroleum cokes by ∼63 mAh/g (∼29.5%) at 150 mA/g in 1 mol/dm3 LiClO4-EC/DEC.  相似文献   

4.
The influence of a thin spreading solvent film (ethanol, diethyl ether, and three fractions of petroleum ether boiling at 30–60 °C, 60–90 °C, and 90–120 °C) on the properties of hexadecan-1-ol (C16H33OH) monolayers at the air—water interface was studied. The specific evaporation resistance and the surface pressure were determined to describe the spreading behavior of the C16H33OH monolayers. The physical properties of the solvents and the images obtained in an atomic force microscope were examined. The time of establishing the equilibrium spreading surface pressure of monolayers can be reduced using a more volatile solvent with a lower boiling point and a lower relative density. The influence of the monolayer nature on water evaporation corresponds to the order of changing the solvent spreading rate: petroleum ether (30–60 °C) > diethyl ether > ethanol > petroleum ether (60–90 °C) > petroleum ether (90–120 °C). The monolayers formed upon petroleum ether (30–60 °C) spreading form a film with a less deficient and relatively planar surface. When ethanol is used as a spreading solvent, water evaporation is accelerated rather than retarded, while petroleum ether (30–60 °C) is more appropriate for this purpose.  相似文献   

5.
Herein, we report the transformation of β‐monomethyl itaconate, an inexpensive and biorenewable alternative to petroleum feedstocks, to the high‐value monomer α‐methylene‐γ,γ‐dimethyl‐γ‐butyrolactone (Me2MBL) through a selective addition strategy. This strategy is also applied to the synthesis of α‐methylene‐γ‐butyrolactone (MBL, tulipalin A), a monomer that can be polymerized to give materials with desirable properties (high decomposition temperature, glass transition temperature, and refractive index). Subsequent polymerization of both Me2MBL and MBL through reversible addition‐fragmentation chain‐transfer polymerization generates well‐defined poly(Me2MBL) and poly(MBL) (PMBL). Physical characterization of poly(Me2MBL) shows good physical properties comparable with known PMBL materials. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2730–2737  相似文献   

6.
A gas chromatographic (GC) method for the determination of petroleum hydrocarbons (PH) in the boiling range from 175°C to 525°C (C10?C40 alkane) in soil was evaluated. The extraction was carried out using minimal amounts of acetone and heptane, prior to a clean up with silica gel. The extraction procedure was tested by means of standard solutions of petroleum products and soil samples. The clean up procedure did not have any significant effect on the amounts of petroleum hydrocarbons present and hydrocarbons of natural origin were removed effectively. The recovery of the extraction and clean up procedure for petroleum products in soil was greater than 90%. The standard deviation for the repeatability was estimated to be less than 10% based on multiple analyses of homogenized soil samples. The detection limit for soil was determined to be 10 mg/kg dry matter. Comparing the GC method with the widely used infrared spectrometry (IR) method in combination with a Soxhlet-extraction using Freon-113, the results obtained are equivalent.  相似文献   

7.
《Analytical letters》2012,45(9):1623-1632
Abstract

A new procedure based on closed vessel Microwave-Induced Combustion (MIC) technique is proposed for the decomposition of petroleum coke and further determination of sulfur by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The procedure is based on sample ignition by microwave radiation using closed quartz vessels pressurized with oxygen and use of NH4NO3 as an ignition aid. The nature and concentration of absorbing/refluxing solution were studied, as well as the operational parameters related to MIC technique. Results were compared with those obtained by conventional wet digestion in closed vessels, certified reference materials (agreement was better than 98%), and also using ion chromatography for S determination.  相似文献   

8.
Pyrolysis is claimed as an alternative method to improve the quality of the products obtained from materials of a hydrocarbon nature such as coal and residues from petroleum distillation. Appearance of synergy in the production of light olefins and aromatic compounds during the co-pyrolysis of coal and petroleum residues has been previously stated. The aliphatic fraction of the petroleum residue (PR) previously studied, might play an important role in the occurrence of the synergy in coal/PR co-pyrolysis reactions. For that reason, different mixtures of Samca coal and a model aliphatic compound (C50), have been co-pyrolysed at 900 °C and atmospheric pressure in a Pyroprobe 1000 CDS. Three different weight ratios coal/PR (70:30, 50:50, 40:60) were studied. Important synergetic effects were observed for the production of light olefins, specially ethylene, after the co-pyrolysis of the three mixtures, but the most intense effects appeared for the 50:50 one. Synergy in the evolution of small aromatic compounds was also observed when 70:30 mixtures were pyrolysed, but the synergy for these compounds disappeared when the ratio of pentacontane in the mixture was increased. These effects are similar to those observed when mixtures of Samca coal and PR were co-pyrolysed in the same experimental conditions, and so that, it can be concluded that the aliphatic fraction of PR is the one that leads the mechanism of the co-pyrolysis process.  相似文献   

9.
碳一化工路线制备乙二醇研究进展   总被引:1,自引:0,他引:1  
宋河远  靳荣华  康美荣  陈静 《催化学报》2013,34(6):1035-1050
乙二醇(EG)是一种重要的化工原料,主要用来生产新型聚酯纤维.近年来由于我国聚酯产业发展迅速,极大的推动了对乙二醇的需求.碳一化工路线以资源丰富、价格便宜的天然气或煤为原料合成乙二醇,有着诱人的工业化前景.综述了以合成气为原料合成乙二醇的研究进展,包括合成气直接合成法、甲醛羰化法、CO偶联法、甲醛氢甲酰化法以及甲醛缩合法等.  相似文献   

10.
Given increasing environmental issues due to the large usage of non‐biodegradable plastics based on petroleum, new plastic materials, which are economic, environmentally friendly, and recyclable are in high demand. One feasible strategy is the bio‐inspired synthesis of mineral‐based hybrid materials. Herein we report a facile route for an amorphous CaCO3 (ACC)‐based hydrogel consisting of very small ACC nanoparticles physically cross‐linked by poly(acrylic acid). The hydrogel is shapeable, stretchable, and self‐healable. Upon drying, the hydrogel forms free‐standing, rigid, and transparent objects with remarkable mechanical performance. By swelling in water, the material can completely recover the initial hydrogel state. As a matrix, thermochromism can also be easily introduced. The present hybrid hydrogel may represent a new class of plastic materials, the “mineral plastics”.  相似文献   

11.
CO2 enhanced oil recovery (CO2-EOR) has become significantly crucial to the petroleum industry, in particular, CO2 miscible flooding can greatly improve the efficiency of EOR. Minimum miscibility pressure (MMP) is a vital factor affecting CO2 flooding, which determines the yield and economic benefit of oil recovery. Therefore, it is important to predict this property for a successful field development plan. In this study, a novel model based on molecular dynamics to determine MMP was developed. The model characterized a miscible state by calculating the ratio of CO2 and crude oil atoms that pass through the initial interface. The whole process was not affected by other external objective factors. We compared our model with several famous empirical correlations, and obtained satisfactory results—the relative errors were 8.53% and 13.71% for the two equations derived from our model. Furthermore, we found the MMPs predicted by different reference materials (i.e., CO2/crude oil) were approximately linear (R2 = 0.955). We also confirmed the linear relationship between MMP and reservoir temperature (TR). The correlation coefficient was about 0.15 MPa/K in the present study.  相似文献   

12.
The utilization of associated petroleum gas via power generation in modern gas piston engines or gas turbines involves some difficulties due to a significant content of heavy C5+ hydrocarbons which are prone to detonation and soot and tar formation. Two pretreatment technologies were described for associated petroleum gas utilization via power generation. Selective oxycracking of heavy hydrocarbons in associated petroleum gas allows their conversion to lighter and high octane molecules. The conversion of associated petroleum gas into syngas with the use of volumetric radiant matrix not only enables utilization of associated petroleum via power generation but also opens prospects for its complete utilization with production of synthetic liquid hydrocarbons via Fischer-Tropsch synthesis route.  相似文献   

13.
Mold fluxes develop important functions during steel continuous casting process. To obtain a free-defect product the melting rate of mold flux is an important property to be controlled. The melting rate depends on the reactivity of carbonaceous material added to these powders as carbon source. In this article, the decomposition kinetic of two carbonaceous materials added to mold flux: petroleum coke and synthetic graphite, was analyzed. By measuring mass loss at different heating rates the decomposition reaction was determined on both types of materials. Applying several kinetic models of non-isothermal decomposition, the average activation energy E = 48 kJ/mol to mold powder with 15 wt% coke and E = 67 kJ/mol to one with 15 wt% graphite was determined. A first order of reaction (n = 1) associated to the decomposition process was assumed to both types of materials. The lower activation energy presented by mold powder-15 wt% petroleum coke indicated a higher reactivity of this material. A higher level of variation of E and n values with decomposition degree and temperature observed in the powder with petroleum coke was associated to a less thermally stable material along with a more complex degradation process.  相似文献   

14.
“Total petroleum hydrocarbons” (TPHs) or “petroleum hydrocarbons” (PHCs) are one of the most widespread soil pollutants in Canada, North America, and worldwide. Clean-up of PHC-contaminated soils and sediments costs the Canadian economy hundreds of million of dollars annually. Much of this activity is driven by the need to meet regulated levels of PHC in soil. These PHC values are legally required to be assessed using standard methods. The method most commonly used in Canada, specified by the Canadian Council of Ministers of the Environment (CCME), measures the total hydrocarbon concentrations in a soil by carbon range (Fraction 1: C6–C10; Fraction 2: C10–C16, Fraction 3: C16–C34: and Fraction 4: C34+). Using the CCME method, all of the materials extractible by a mixture of 1:1 hexane:acetone are considered to be petroleum hydrocarbon contaminants. Many hydrocarbon compounds and other extractible materials in soil, however, may originate from non-petroleum sources. Biogenic organic compounds (BOCs) is a general term used to describe a mixture of organic compounds, including alkanes, sterols and sterones, fatty acids and fatty alcohols, and waxes and wax esters, biosynthesized by living organisms. BOCs are also produced during the early stages of diagenesis in recent aquatic sediments. BOC sources could include vascular plants, algae, bacteria and animals. Plants and algae produce BOCs as protective wax coating that are released back into the sediment at the end of their life cycle. BOCs are natural components of thriving plant communities. Many solvent-extraction methods for assessing soil hydrocarbons, however, such as the CCME method, do not differentiate PHCs from BOCs. The naturally occurring organics present in soils and wet sediments can be easily misidentified and quantified as regulated PHCs during analysis using such methods. In some cases, biogenic interferences can exceed regulatory levels, resulting in remediation of petroleum impacts that are not actually present. Consequently, reliance on these methods can trigger unnecessary and costly remediation, while also wasting valuable landfill space. Therefore, it is critically important to develop new protocols to characterize and differentiate PHCs and BOCs in contaminated sediments. In this study, a new reliable gas chromatography–mass spectrometry (GC–MS) method, in combination with a derivatization technique, for characterization of various biogenic compounds (including biogenic alkanes, sterols, fatty acids and fatty alcohols) and PHCs in the same sample has been developed. A multi-criteria approach has been developed to positively identify the presence of biogenic compounds in soil and sediment samples. More than thirty sediment samples were collected from city stormwater management (SWM) ponds and wetlands across Canada. In these wet sediment samples, abundant biogenic n-alkanes, thirteen biogenic sterols, nineteen fatty carboxylic acids, and fourteen fatty alcohols in a wide carbon range have been positively identified. Both PHCs and BOCs in these samples were quantitatively determined. The quantitation data will be used for assessment of the contamination sites and toxicity risks associated with the CCME Fraction 3 hydrocarbons.  相似文献   

15.

Patents dealing with the production of motor fuel components by hydrodeoxygenation of renewable raw materials based on fatty acid triglycerides are analyzed. Various methods of using sulfide catalysts in hydrodeoxygenation of fatty acid triglycerides and of their mixtures with petroleum fractions are described. The ways to overcome problems that arise in hydrodeoxygenation, based on using sulfide catalysts differing in the active component and support composition, are considered. For example, the use of supported MoS2 catalysts free of Co and Ni ensures the conversion of fatty acid triglycerides along the “direct hydrodeoxygenation” pathway to avoid the formation of carbon oxides and related process problems. The use of sulfide catalysts on zeolite-containing supports allows synthesis of products with improved low-temperature properties due to isomerization (or mild hydrocracking) of С15–С18 alkanes formed by hydrodeoxygenation of fatty acid triglycerides.

  相似文献   

16.
The aromatization of light alkenes in liquefied petroleum gas (LPG) with and without dimethyl ether (DME) addition in the feed was investigated on a modified ZSM-5 catalyst. The results showed that under the given reaction conditions the selectivity of alkenes to high-octane gasoline blending components was markedly enhanced and the formation of propane and butanes was greatly suppressed with the addition of DME. It was also found that the distribution of C5+ components was changed a lot with DME addition into the LPG feed. The formation of branched hydrocarbons (mainly C6?C8 i-paraffin) and multi-methyl substituted aromatics, which are high octane number gasoline blending components, was promoted significantly, while the content of n-paraffins and olefins in C5+ components was decreased obviously, indicating that in addition to the oligomerization, cracking, hydrogen-transfer and dehydrogenation-cyclization of alkenes, the methylation of the formed aromatics and olefins intermediates also plays an important role in determining the product distribution due to the high reactivity of surface methoxy groups formed by DME. And this process, in combination with the syngas-to-methanol/DME technology, provides an alternative way to the production of high-octane gasoline from coal, natural gas or renewable raw materials.  相似文献   

17.
The world polymer industry claims over 2 million tons per year, though most synthetic polymers use petroleum feedstocks, there is a growing effort to prepare polymers from renewable raw materials concerning the depleting fossil fuel resources. In this short review, we would like to emphasize the potential that CO2 based polymers, polycarbonates and polyurethanes from copolymerization of CO2 and epoxides, have to mitigate the above concerns, where the newly developed metal catalyst systems allow not only their high efficient synthesis, significant advances have been achieved in stereo-controlled copolymerization. It is also noteworthy that the physical and chemical properties of CO2 based polymers may be tailored, which help to pave the way from their lab curiosities to practical application, as new applications have been realized such as biodegradable disposal bags, and hydrolysis and oxidation resistant water borne adhesives.  相似文献   

18.
A simplified equation relating water droplet size distribution to crystallization temperature, determined from differential scanning calorimetry (DSC) curves of aqueous emulsions of petroleum is reported in this article. A series of water-in-oil (W/O) emulsions was prepared by dispersion of water in different Mexican crude oils; in a classical DSC experiment, these emulsions were submitted to a regular heating and cooling cycle within temperatures including freezing and heating of dispersed water. The Z-average diameters of the water drops (D dz) were estimated this way and correlated with petroleum composition.  相似文献   

19.
Abstract

Vegetable oil based environmentally friendly polyurethane-TiO2 nanocomposite coatings have been synthesized by using sunflower oil derived diol, toluene diisocyanate and TiO2 nanoparticles. The chemical structure was confirmed by FTIR and NMR techniques while physico-chemical testing was carried out by standard laboratory methods. Physico-mechanical and anticorrosive tests of the coatings (in different corrosive media) have been investigated by standard methods. In addition to this the morphology and thermal stability behavior of the coatings have been carefully investigated by different techniques like XRD, TEM, TGA/DTG and DSC. The comparison of the performance of nanocomposites with the respective virgin polyurethane coatings reveals that the dispersion of nanoTiO2 enhanced the mechanical, corrosion and thermal stability behavior of the polymer. The synthesized nanocomposites can be used safely upto 250–275?°C. These sunflower oil derived polyurethane nanocomposites can be used in the world of protective coatings, as an alternative of petroleum derived corrosion protective coating materials.  相似文献   

20.
The co-pyrolysis of a petroleum residue with two different sources of titanium (tetrabutyl-ortotitanate (TBO) or titanium carbide nano-powder) was carried out to obtain mesophase pitches containing TiO2 or TiC nanoparticles. Co-pyrolysis is an appropriate technique to achieve a good dispersion and low particle size. In the case of TBO, TiO2 nanoparticles (5–20 nm) are observed, which are forming aggregates, the largest of them being 1–2 μm. In the case of TiC nano-particles, they are more difficult to disperse and larger aggregates are formed, although the final material is rather homogenous. The chemistry of pyrolysis for the production of doped and undoped mesophase pitches has been followed by means of solvent insolubility, XRD, XPS, FTIR and elemental analysis. They show evidences of promotion of the formation of mesophase in the presence of the titanium-containing particles, especially in the presence of TiO2. The final materials can be of great value as precursors to produce high density titanium doped graphites for nuclear and space applications.  相似文献   

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