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1.
Materials (Basel) ; 16(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36837047

RESUMO

Unsaturated C4 hydrocarbons are abundant in various petrochemical streams. They can be considered as a potential feedstock for the steam-cracking process, where they must be co-processed with C6 and higher (C6+) hydrocarbons of primary naphtha fractions. Co-pyrolysis experiments aiming at the comparison of different C4 hydrocarbon performances were carried out in a laboratory micro-pyrolysis reactor under standardized conditions: 820 °C, 400 kPa, and 0.2 s residence time in the reaction zone. C4 hydrocarbons were co-pyrolyzed with different co-pyrolysis partners containing longer hydrocarbon chain to study the influence of the co-pyrolysis partner structure on the behavior of C4 hydrocarbons. The yields of the pyrolysis products and the conversion of C4 hydrocarbons were used as the performance factors. A regression model was developed and used as a valuable tool for quantifying the inhibition or acceleration effect of co-pyrolysis on the conversion of co-pyrolyzed hydrocarbons. It was found that the performance of different C4 hydrocarbons in co-pyrolysis is substantially different from the separate pyrolysis of the individual components.

2.
Polymers (Basel) ; 14(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35215580

RESUMO

ORLEN Unipetrol's Steam Cracking unit processes a wide range of hydrocarbons from gases to heavy oils produced in refinery processes. Due to the heavy feedstock, the Steam Cracking unit can produce very valuable hydrocarbons such as cyclopentadiene and dicyclopentadiene in addition to ethylene, propylene and benzene. These hydrocarbons can be obtained and used as very profitable monomers for many other chemical applications. ORLEN Unipetrpol, in cooperation with the University of Chemistry and Technology in Prague, has developed a technology for the isolation of technical dicyclopentadiene of both medium purity grades and high purity grades. Making DCPD grades will add considerable value to the raw C5 by-product stream from the Steam Cracker pyrolysis gasoline. The capacity of the new existing DCPD unit is expected to be in the range of 20-26 thousand metric tons per year, depending on the derivative product portfolio and purity of the DCPD. The construction of the unit started in September 2020, and production is expected to be launched in the second half of 2022.

3.
Materials (Basel) ; 14(19)2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34639994

RESUMO

In this paper, the fuel properties of mixtures of diesel fuel and ethanol and diesel fuel and butanol in the ratio of 2.5% to 30% were investigated. The physicochemical properties of the blends such as the cetane number, cetane index, density, flash point, kinematic viscosity, lubricity, CFPP, and distillation characteristics were measured, and the effect on fuel properties was evaluated. These properties were compared with the current EN 590+A1 standard to evaluate the suitability of the blends for use in unmodified engines. The alcohols were found to be a suitable bio-component diesel fuel additive. For most physicochemical properties, butanol was found to have more suitable properties than ethanol when used in diesel engines. The results show that for some properties, a butanol-diesel fuel mixture can be mixed up to a ratio of 15%. Other properties would meet the standard by a suitable choice of base diesel.

4.
Polymers (Basel) ; 13(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34578034

RESUMO

Dicyclopentadiene (DCPD) modified unsaturated polyester resins (UPRs) are mostly used for hulls, decks, and bathroom facilities. Main advantages of these polymers over orthophthalic or isophthalic polyesters are their relatively low shrinking, reduced styrene emission, lower cost, and fast curing in thin layers. On the other hand, once cured, these materials are more brittle and have lower glass transition temperatures and lower chemical resistance due to their different chemical constitutions. DCPD UPRs with standard grades are usually produced with high-quality DCPD (over a 85% purity) using the so-called "water process", a synthesis consisting of two reaction steps. An adduct of maleic anhydride with DCPD is firstly formed with water, and then, it reacts with the other esterification monomers such as acids and glycols. DCPD raw materials used in this study were prepared by a unique distillation process developed by ORLEN Unipetrol and University of Chemistry and Technology, Prague. This technology allows producing a wide spectrum of DCPD quality by adjusting the content of another norbornene dimer: methyl dicyclopentadiene (MeDCPD). The influence of MeDCPD on unsaturated polyester properties was examined throughout this study. It has been discovered that in low concentrations, MeDCPD had a slight influence on flexural mechanical properties whereas its concentrations up to 65% led to a softer and brittle material. Nevertheless, by adjusting the unsaturation degree, it has been shown that MeDCPD may be successfully implanted in UPR formulation.

5.
Materials (Basel) ; 14(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199859

RESUMO

This paper focuses on the evaluation of the fuel properties of Fischer-Tropsch diesel blends with conventional diesel. Incorporating this advanced fuel into conventional diesel production will enable the use of waste materials and non-food materials as resources, while contributing to a reduction in dependence on crude oil. To evaluate the suitability of using Fischer-Tropsch diesel, cetane number, cetane index, CFPP, density, flash point, heat of combustion, lubricity, viscosity, distillation curve, and fuel composition ratios using multidimensional GC × GC-TOFMS for different blends were measured. It was found that the fuel properties of the blended fuel are comparable to conventional diesel and even outperform conventional fuel in some parameters. All measurements were performed according to current standards, thus ensuring the repeatability of measurements for other research groups or the private sector.

6.
Materials (Basel) ; 14(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200359

RESUMO

The aim of the article is to determine the properties of fuel mixtures of Fischer-Tropsch naphtha fraction with traditional gasoline (petrol) to be able to integrate the production of advanced alternative fuel based on Fischer-Tropsch synthesis into existing fuel markets. The density, octane number, vapor pressure, cloud point, water content, sulphur content, refractive index, ASTM color, heat of combustion, and fuel composition were measured using the gas chromatography method PIONA. It was found that fuel properties of Fischer-Tropsch naphtha fraction is not much comparable to conventional gasoline (petrol) due to the high n-alkane content. This research work recommends the creation of a low-percentage mixture of 3 vol.% of FT naphtha fraction with traditional gasoline to minimize negative effects-similar to the current legislative limit of 5 vol.% of bioethanol in E5 gasoline. FT naphtha fraction as a biocomponent does not contain sulphur or polyaromatic hydrocarbons nor benzene. Waste materials can be processed by FT synthesis. Fischer-Tropsch synthesis can be considered a universal fuel-the naphtha fraction cut can be declared as a biocomponent for gasoline fuel without any further necessary catalytic upgrading.

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