Paraffinic-naphthenic Hydrocarbons Research Articles

A comparison of results of determining the hydrocarbon group-type composition of petroleum samples obtained using various test methods of open-column liquid chromatography

The hydrocarbon group-type composition (so-called SARA-composition) is one of the main characteristics of oil, providing an information about its chemical nature and determining the quality of the obtained petroleum products. In world laboratory practice, data on the hydrocarbon group-type composition of petroleum feedstock are widely used to assess its colloidal stability and compatibility with crude oil, reactivity in various conversion processes, predicting physical properties, etc. Traditionally, the hydrocarbon group-type composition is determined in accordance with standard and research chromatographic methods that differ significantly from each other, which often leads to obtaining incomparable analytical results. In this paper, a comparative analysis of the results of determining the hydrocarbon group-type composition obtained in accordance with two test methods within the open-column liquid chromatography method is carried out for various of petroleum samples of Russian origin (commercial oils of different classes and two petroleum products). Using the standard test method ASTM D4124 (method B) and the research test method developed by JSC VNII NP, the content of identical hydrocarbon groups in the maltene part of petroleum samples was determined: saturated hydrocarbons (SH) and paraffinic-naphthenic hydrocarbons (PNH), naphthenic aromatic (NAH) and aromatic hydrocarbons (AH), polar aromatic hydrocarbons (PAH) and resins (R), respectively. It is shown that with an increase the density and viscosity of petroleum samples, the content of less polar groups (SH and PNH) in their composition decreases and the content of more polar groups (PAH and R) obviously increases, and there is no pronounced distribution pattern of the NAH and AH groups. Statistical processing revealed insignificant differences in the results for «heavy and viscous» oils, despite the large error of those obtained according to the research test method. Obtaining comparable results justifies the use of both test methods not only for the analysis of high-boiling petroleum products, but also for the analysis «heavy and viscous» oil samples.

THE IMPACT OF FRACTIONAL COMPOSITION OF GAS OIL ON THE YIELD AND QUALITY OF CATALYTIC CRACKING PRODUCTS

The impact of the depth of selection of narrow gas oil fractions of Azeri-Chirag-Guneshli oils on the yield and quality of catalytic cracking products was studied. The impact of fractional and group hydrocarbon composition on the main directions of cracking is analyzed. 5 types of gas oil fractions selected in the range of 200-360, 200-410, 200-440, 200-460, and 200-500°C were used as feedstock for catalytic cracking. The results of catalytic cracking of narrow gas oil fractions of Azeri-Chirag-Guneshli oils indicate a nonlinear nature of the dependences on the boiling point limits. The highest total yield of light oil products was obtained by cracking gas oil fractions boiling in the range of 200-410 and 200-440°C, reaching 60.5 and 60.8%, respectively. At the same time, the main contribution to this indicator was made by the gasoline fraction (31.5-33.2%). It was based on paraffin-naphthenic hydrocarbons. The yield of the diesel fraction changed symbiotically with the increasing weight of the fractional composition of the raw material, reaching maximum values of 9.9% during the cracking of the gas oil fraction, boiling in the range of 200-500°C. Based on a comparison of the ratio of iso-butane to iso-butylene, it was concluded that the cracking of gas oil at 200-440°C was accompanied by a significant contribution of bimolecular hydrogen transfer reactions.

Możliwość produkcji materiałów wtórnych z odpadów węglowodorowych

The utilisation and processing of crude oil sludge is one of the major global challenges. Therefore, it is necessary to justify the following scientific solutions in the field of oil sludge utilisation and processing worldwide: the study of the physicochemical properties of oil sludge in order to obtain construction grade bitumen; detection of dispersion of solid particles in the composition of oil sludge; development of the optimal technological parameters for the process of obtaining construction grade bitumen from oil sludge; establishing a correlation dependence between process efficiency and the environment, the content of light fractions in the sludge composition, the process temperature. In this work, oil sludge was diluted with a solvent in a ratio of 70:30, with light naphtha used as a solvent. A laboratory distillation column was used to separate the sludge into fractions, and the chemical composition of the oil sludge was investigated. Oil sludge consists of asphaltenes up to 4.2–4.5%, resins up to 21.0%; paraffin-naphthenic hydrocarbons up to 41.2%; monocyclic aromatic hydrocarbons up to 4.6%; bi- and tricyclic aromatic hydrocarbons up to 5.8%; polycyclic aromatic hydrocarbons up to 9.7%. The paper also presents the results of the change in the viscosity and density of the distillate fractions separated during the distillation of diluted oil sludge. Density and viscosity were measured using an areometer and a VPZh-4, respectively. One of the main components of the oil sludge is water. A series of experiments were conducted to determine the water content using the Dean and Stark method. In addition, the sulphur content in oil sludge diluted with solvents – light and heavy naphtha, heavy gas oil – was determined.

Use of carbon black as a modifier for petroleum bitumen

The problem of recycling worn-out tires and recycling of solid carbon-containing residue from the pyrolysis of tires is considered. The possibility of processing carbon black from the pyrolysis of tires into a high-quality concentrate, which can serve as a raw material for modifying petroleum bitumen, has been shown. The nature of the interactions occurring between the components of carbon black and the matrix of petroleum road bitumens has been studied. The chemical interaction of carbon black with the bitumen matrix through unsaturated C=C bonds has been proven. The introduction of carbon black as a modifying additive leads to a significant change in the physical, mechanical and rheological properties of the resulting bitumen binder systems. Based on spectrometric studies, an assessment is made of the structural changes occurring in the original and modified bitumen during the production of modified bitumen binders. It has been established that with such modification, diffusion of aromatic hydrocarbons occurs from the bitumen component into the modifier particles. During the modification process, six-membered cyclic aromatic compounds are formed in the bitumen part, the composition of paraffin-naphthenic hydrocarbons changes, and sulfur compounds are formed that “transfer” from the modifier particles to the bitumen. Thus, in this study, the phenomenon of mutual diffusion between bitumen and CBWT modifier was confirmed using IR spectroscopy.

ИСПОЛЬЗОВАНИЕ ГИДРОКРЕКИНГА ПРИ ПЕРЕРАБОТКЕ СВЕРХВЯЗКОЙ НЕФТИ АШАЛЬЧИНСКОГО МЕСТОРОЖДЕНИЯ

The high necessity of development of innovative technologies for heavy oil processing is caused by decreasing reserves and increasing volumes of conditioned oil and gas fields in the world. One of the alternatives to primary processing of heavy oils, implemented at the fields, can be technologies based on extraction processes to obtain deasphalted oil. The present study is aimed at studying the products of various stages of hydrotreating of heavy high-sulfur deasphalted oil from the Ashalchinskoye field (Tatarstan, Russia) in the presence of aluminocobaltmolybdenum and aluminoplatinum catalysts. Conversion of deasphalted heavy oil on aluminocobaltmolybdenum catalyst in the hydrocracking process led to changes in the properties and composition of distillate fractions. Decrease in the content of bicyclic aromatic hydrocarbons, increase in the amount of monocycloaromatic and paraffin-naphthenic hydrocarbons, decrease in refractive indices, density and viscosity of distillate fractions were found. The revealed regularities in the composition of hydrotreating products testify to the hydrogenation reactions of polycyclic aromatic compounds, naphthene rings splitting, decomposition of long paraffin chains and their isomerization. It was shown that sulfur compounds contained in different fractions of deasphalted heavy oil differ in their stability to transformation reactions under conditions of catalytic hydrogenation on aluminocobalt-molybdenum catalyst. The second stage of hydrogenation on aluminoplatinum catalyst allowed to reduce the sulphur content in the final product to 0.035 % wt. The obtained data on the composition and technological properties of products of catalytic hydrotreating of heavy deasphalted oil from Ashalchinskoye field indicate the possibility of using widely available aluminocobaltmolybdenum catalysts in processing to obtain high quality hydrocarbon feedstock for petrochemical processes.

Influence of group chemical composition of highly viscous oil residues on quality of petroleum road bitumens

The Kalamkas deposit’s oil and its distillation products were studied, and research results on residues and road grade bitumen compositions obtained by oxidation of heavy oil residuest are presented. The atmospheric residue of Kalamkas oil (350 Со) was subjected to vacuum distillation with the selection of gas oil fractions boiling to 380, 400 and 420 Со. Samples of residues were subjected to oxidation in a laboratory installation, which is a batch cube at constant operating conditions. The residues from different depths of gas oil fractions are characterized by different group chemical compositions. The group composition of the residues changes, the content of paraffinnaphthenic hydrocarbons decreases from 29.4 to 23.3% wt. and the proportion of heavy aromatic hydrocarbons increases from 26.8 to 27.8% wt. The content of asphaltenes (from 7.7 to 12.4% wt) and resins (from 17.4 to 22.5% wt) also increases. The ratio of asphaltenes and resins increases from 0.44 to 0.55. With an increase in the depth of selection of gas oil fractions to 420°C, the degree of aromaticity, the ratio of the amount of aromatic hydrocarbons to paraffin-naphthenic ones, increases to 1.79. Road grade bitumens produced from the vacuum distillation residues of Kalamkas oil fuel oil using direct oxidation technology of raw materials have the best performance characteristics if they are obtained from residues boiling in the range of 380–400°C. Residues boiling above 380-400 Со can serve as raw materials for the production of oxidized road bitumen of BND70/100 grade according to ST RK 1373 - 2013.

Study into the effect of plasticizer nature on the properties of polymer-bitumen compositions via fluorescence microscopy

The paper studies how the nature of the plasticizer affects the properties of polymer-bitumen compositions using the fluorescence microscopy. The current petroleum road bitumen used for the construction of road, bridge, and airfield pavements does not meet the requirements for cracking/heat resistance, elasticity, and adhesion to the mineral material surface. Pavement performance characteristics can be significantly improved by introducing thermoplastic elastomers, plasticizers, and surfactants into the composition of petroleum road bitumen. The best results were obtained when using a block copolymer of styrene and butadiene, industrial oil, and cationic surfactant on the basis of polyaminoamides and polyaminoimidazolines. The choice of industrial oil as a plasticizer is attributed to its good compatibility with bitumen and polymer, as well as its high flash point (200 °С). The content of paraffin-naphthenic hydrocarbons in industrial oil is over 70%. Although industrial oil is produced in large quantities, an acute shortage of this petrochemical product is observed due to its wide application; thus, intensive studies are underway to replace industrial oil in the composition of the polymer-bitumen binder. It is proposed to use heavy gas oil produced via catalytic cracking and delayed coking, heavy pyrolysis tar, solvent-extracted oil, and tall oil as plasticizers in the creation of the polymer-bitumen binder. In this connection, the effect of proposed plasticizers on the colloidal structure of the polymer-bitumen binder was studied using the method of fluorescence microscopy. Initial polymer-bitumen binders were produced at ANHK (Angarsk) according to GOST R 52056-2003 Polymer-Bitumen Road Binders Based on Styrene-Butadiene-Styrene-Type Block Polymers. The group composition of the plasticizers under study was determined. It was shown that in order to obtain a polymer-bitumen binder resistant to stratification, plasticizers having a content of aromatic compounds of over 60% are required.

STUDY OF AMINOESTERS OF SYNTHETIC PETROLEUM ACID PRODUCED BY AEROBIC OXIDATION OF NAPHTHEN-PARAFFIN HYDROCARBONS, AS CORROSION INHIBITORS

This article presents the results of research in the field of synthesis of amino esters obtained on the basis of mono, di, triethanolamine and synthetic petroleum acid in a molar ratio of 1:1.The structure and structure of the obtained substances were confirmed by IR spectroscopy. The inhibitor-bactericidal effect of amino esterson the corrosion process has been studied. The inhibitory effect of the synthesized amino esters on CO2 steel corrosion at concentrations of 25, 50, and 100 mg/L was studied. Samples T-1, T-2, T-3 at a concentration of 25 mg/l for 20 hours showed an inhibitory effect of 40,36…74,15%, respectively, at a concentration of 50 mg/l, respectively 79,96…92,04 %, at a concentration of 100 mg/l, respectively, 98,09…99,59%. In order to study the antimicrobial activity of the obtained amino esters, their solutions were prepared in various media (isopropyl alcohol 60%) at five different concentrations (5; 50; 500; 600; 700 mg/l) and their effect on the vital activity of sulfate-reducing bacteria (SRB) was studied at 30…32 °C for 15 days. It has been established that at a concentration of 600 mg/l, the synthesized amino esters exhibit a 95,2…100% bactericidal effect, and at a concentration of 700 mg/l, they exhibit a 100% bactericidal effect, completely suppressing the vital activity of bacteria. The synthesized complexes exhibit a higher bactericidal effect even at low concentrations. Thus, the bactericidal and CO2-corrosion-inhibiting properties of amino esters synthesized on the basis of synthetic petroleum acid obtained in the process of aerobic oxidation of paraffin-naphthenic hydrocarbons isolated from the diesel fraction (boiling range 190…330 °C) in the presence of transition-metal-modified nanosized γ-Al2O3 catalyst, and ethanolamines.

The Influence of Stream Treatment on the Activity of Iron-Pillared Montmorillonite in Vacuum Gas Oil Cracking

This study considers the influence of stream treatment on the activity if iron-pillared montmorillonite in vacuum gas oil cracking and the change in its physical-chemical characteristics. Stream treatment was demonstrated to result in a decreased specific surface area and iron and silicon content, as well as in the strengthening of the catalysts. After stream treatment, gasoline and gas yield is reduced and raw material conversion decreases. Before stream treatment, the proportion of aromatic hydrocarbons in cracking gasoline does not exceed 24.1%, while the isoparaffin content is 24,5%. After stream treatment, the aromatization of gasoline increases and the content of paraffin-naphthenic hydrocarbons decreases. The main component of cracking gases is butane-butylene fraction with a content equal to about 40% before stream treatment, which remains unchanged after processing.

Influence of parameters of delayed asphalt coking process on yield and quality of liquid and solid-phase products

Paper studies the effect of excess pressure during delayed coking of asphalt, obtained by propane deasphaltization of tar, on yield and physical and chemical properties of hydrocarbon fuels' components and solid-phase product – petroleum coke. Asphalt was coked at a temperature of 500 °C and excess pressure of 0.15-0.35 MPa in a laboratory unit for delayed coking of periodic action. Physical and chemical properties of raw materials and components of light (gasoline), medium (light gasoil), and heavy (heavy gasoil) distillates obtained during experimental study were determined: density, viscosity, coking ability, sulfur content, iodine number, pour points, flash points, fluidity loss and fractional composition. Quantitative group hydrocarbon and microelement compositions and properties of obtained samples of petroleum coke (humidity, ash content, volatiles' yield, sulfur content, etc.) were also studied. Comparative assessment of their quality is given in accordance with requirements of GOST 22898-78 “Low-sulfur petroleum coke. Specifications”. In addition, patterns of changes in excess coking pressure on yield and quality indicators of distillate products and petroleum coke were revealed. With an increase in excess pressure of coking process from 0.15 to 0.35 MPa, content of paraffin-naphthenic hydrocarbons in light and heavy gasoils of delayed coking decreases. Common pattern in asphalt coking is an increase in yield of coke and hydrocarbon gas with an increase in excess pressure from 0.15 to 0.35 MPa.

Heavy Oil Hydroconversion in the Presence of Ultrafine Catalyst

The hydroconversion of heavy oil in the presence of an in situ synthesized catalyst (MoS2) is studied. It is shown that ultrafine aggregates of amorphous components and crystalline particles of molybdenum sulfide with a particle diameter of 20–70 nm are formed from catalyst precursor (ammonium paramolydbate) emulsion under hydroconversion conditions in a medium of heavy oil. The kinetic characteristics of the hydroconversion of heavy oil and separate groups of its components—paraffin-naphthene hydrocarbons, aromatic hydrocarbons, resins, and asphaltenes—are determined.

Hydrocarbons in the Products of Oxidative-Hydrolytic Transformation of Sapropelites

The qualitative and quantitative composition of hydrocarbons formed during oxidative-hydrolytic treatment of Kuzbas and Mongolian sapropelic oil shales under hydrous pyrolysis conditions was determined by chromato-mass spectrometry. It was shown that oxidative-hydrolytic transformations of the organic mass of these sapropelites at 400°C in aqueous-alkaline solution are due to the extent of 30-40% to the formation of paraffinic-naphthenic hydrocarbons, primarily normal C10- C31 alkanes and normal C14- C28 alkenes. It was found that, in contrast to the anhydrous pyrolysis products, the destructive oxidation-hydrolysis products contain more monounsaturated olefins with the double bond in a different position. The composition of the hydrocarbon biomarkers confirms the marine origin of the original biomass of the studied oil shales.

Change of the composition parafinnaphthenic hydrocarbon fraction in biological purification of water of oil

Investigated are changes in the composition of paraffin-naphthenic hydrocarbons (PNH) in purifying water by the preparation Ekolan-M of crude oil. The main components of PNH are n-alkanes C9–C30 and iso-alkanes C8–C17. The absence in the purified water of iso-alkanes C9 and the presence in it of a small amount of n-alkanes C22–C26, whose concentration decreased compared with the initial one by 150–234 times is an evidence of nearly complete utilization by microorganism of the preparation of these fractions of hydrocarbons.

Synthesis and properties of bitumen from the residues of ‘charcoal oil’

For the first time, the liquid road bitumen is obtained from the residues formed after hydrogenation of charcoal of ‘Karazhyra’ mine field. According to the values of physical–mechanical indicators, obtained bitumen corresponds to the bitumen of mark MG70/130. Chemical composition of obtained bitumen: 64% mass, paraffin–naphthene hydrocarbons; 13·48% mass, asphaltenes; 21·75% mass, resins. The viscous road oil bitumen is obtained by oxidation of liquid road bitumen, corresponding to bitumen of mark BND130/200 in terms of physical–mechanical indicators.

Chemical transformations of components of raffinates from selective refining of sulfurous crude oils in the process of hydrotreating in production of base oils of API group II

Variation of the chemical composition and properties of raffinates from selective refining of sulfurous crude oils in the course of hydrofining in the presence of a zinc-modified catalyst was studied. In hydrofining of the raffinate obtained at the N-methylpyrrolidone: distillate weight ratio of 1.2: 1 at 360°C, “light” aromatic hydrocarbons (n D 20 = 1.4900–1.5100) start to undergo hydrogenation with the formation of high-index paraffin-naphthene hydrocarbons. At the same temperature, tetra-, penta-, and hexacyclic naphthenes undergo active hydrodecyclization with the formation of high-index mono-, bi-, and tricyclic structures. From the hydrogenizates obtained at 360 and 380°C, after dewaxing, base oil samples were obtained with the sulfur content of 0.020–0.024 wt %, content of saturated compounds of 91.2–91.4 wt %, and viscosity index of 88–91, meeting the requirements of API group II. There are prospects for further improving the quality of the hydrogenizates by varying the hydrofining process parameters (decreasing the space velocity to 0.5–0.75 h−1, increasing the hydrogen circulation factor).

Influence of the hydrocarbon composition of diesel fuels on their performance characteristics

The influence of different groups of diesel hydrocarbons on the physicochemical properties and performance characteristics of diesel fuels has been considered. The parameters to be evaluated have been cetane number, cetane index, diesel index, pour point, and cold filter plugging point. It has been shown that the hydrocarbon group composition, which reflects only the amount of arenes and paraffinic-naphthenic hydrocarbons, gives insufficient information for prediction of the performance properties of fuels. A more detailed study of the hydrocarbon composition of each group of compounds—the ratio of mono-, bi-, polycyclic arenes, the concentration and the ratio of high- and low-melting-point n-alkanes and isoalkanes—has made it possible to reveal the influence of each group on individual fuel characteristics.

Poisoning effect of nitrogen compounds on the transformation of model hydrocarbons and real feed under catalytic cracking conditions

The effect of the content and nature of nitrogen compounds on the distribution of target products in transforming model hydrocarbons under cracking conditions over equilibrium zeolite-containing catalyst was studied. Using cracking of n-undecane as an example, a nearly 50% drop in the conversion and in yields of propane-propene (PPF) and butane-butene fractions (BBF) was observed when the pyrrol content in the feed was raised to 3000 ppm of nitrogen. Increasing the nitrogen content in the feed led to a nonlinear reduction in the rate constants of n-undecane cracking. It was found that the dependence of the yields of PPF, BBF, and isobutane in BBF on the conversion remained constant upon the cracking of n-undecane with various of nitrogen compounds; poisoning was likely to proceeds only because the acidic sites of the catalyst were blocked. The high poisoning effect of pyrrol and indole upon the cracking of n-undecane and decalin (strong proton donors) was observed along with the formation of ammonia. Quinoline exhibited high poisoning ability in the catalytic cracking of cumene with low [H]-donor activity. Quinoline poisoned catalysts to a greater degree than indole, during the catalytic cracking of non-hydrofined vacuum gasoil with a high content of aromatic structures. Indole exhibited the highest poisoning ability in processing heavy hydrocracking residue which was rich of paraffin-naphthene hydrocarbons.

Hydrogenation processes for white-oil production from Ashal’cha heavy crude

It is shown that high-quality commercial-grade white oils can be obtained from heavy high-sulfur Ashal’cha field oil by hydrogenation processes using commercial aluminum-cobalt-molybdenum and aluminum-platinum catalysts. It is found that the 354-376 °C fraction of the oil contains organo-sulfuric compounds that are most resistant to hydrogenolysis, which must be taken into account in producing the white oils. It is established that in terms of a number of characteristics, concentrates of paraffinic-naphthenic hydrocarbons correspond to white oils suitable for perfumery and the pharmaceutical industry.

Influence of the chemical composition of oxidation feedstock on the yield of black furnace oil, a byproduct of the manufacturing of air-blown asphalts

The effect of the chemical composition of short residues, a feedstock for the manufacturing of airblown asphalt on the yield of the byproduct black furnace oil was studied. It was shown that paraffin-naphthene hydrocarbons present in short residues are the major source of the formation of black furnace oil. It was found that the paraffin-naphthene hydrocarbons remaining unreacted during the oxidation of asphalts make up a considerable portion of the black oil produced upon asphalt manufacturing.

Catalytic cracking in presence of activating additive

The results of the catalytic cracking of vacuum distillate of Baku oils (Table 2) show that with increase of the additive content the yield of the cracking gases differs little and the coke yield first decreases and then increases. The minimum coke content on the catalyst (1.6 wt.%) is attained at the optimal additive content of 2 wt.%. The yield of the benzine fraction and light gas oil in this case is slightly higher than the yield from the starting stock and the selectivity with respect to benzine (the ratio of the yield of the benzine fraction to the stock conversion degree) rises from 64.5 to 67.8 %. The coke formation diminishes due to increased benzine and gas oil yield. The minimum content of unsaturated and the maximum content of paraffin-naphthene hydrocarbons in the benzine fraction corresponds to the ,optimum additive content in the stock (2 %), which bears evidence of more intense redistribution of hydrogen atoms in the molecules of the compounds representing the cracking products (Table 3). The results of the catalytic cracking in presence of the activating additive can be explained by the change in the kinetic stability of the stock. It is known that upon addition of aromatized activating additives to vacuum distillates the curves of the structural viscosity of the mixtures obtained acquire an extremal-nature; the minimum viscosity of the system