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Biomass heavy oil, a renewable green energy source, has been extensively explored for its preparation process and material properties. This study examined the applicability of biomass heavy oil integrated into matrix asphalt. Bio-asphalt samples were prepared using polymer-modified asphalt I-C as the matrix asphalt, blended with straw liquid oil, straw solid oil, and castor liquid oil. The low-temperature performances of these samples were assessed. First, the effects of bio-oil on the fundamental performance of asphalt were analyzed through three-component tests, encompassing a short-term aging test and a temperature scanning test based on dynamic shear rheometry. Subsequently, the effects of the chemical composition of bio-asphalt on its fundamental performance were examined through four-component tests, including SARA, gel-permeation chromatography (GPC), and gray entropy correlation. The glass transition temperature (Tg) was considered a parameter for evaluating the low-temperature properties of the bio-asphalt binders. The bending-beam rheometry (BBR) low-temperature creep test and the binder fracture energy (BFE) full-section fracture energy test revealed that adding bio-oil reduces Tg of the matrix asphalt. The integrated creep flexural parameter Jc and the BFE fracture energy density values indicated that the low-temperature fracture-resistant properties of bio-asphalt surpass those of the matrix asphalt. Furthermore, the low-temperature cracking resistance of the bio-asphalt samples was determined through the BFE test. Gray entropy correlation analysis of the low-temperature performance indicators of bio-asphalt revealed that the BBR test is suitable for evaluating low-temperature performance only up to − 12 °C. In summary, the bio-asphalt mixtures demonstrate exceptional fatigue resistance under low-temperature service conditions. Therefore, bio-oil emerges as an effective candidate for enhancing the low-temperature performance characteristics of matrix asphalt.

This study explores the impact of butadiene rubber (BR) crystallization on the low-temperature properties of butadiene/silicone (VMQ) rubber blends (BR/VMQ) designed for Martian applications. Two types of BR, semi-crystalline high-cis Buna CB24 and amorphous Buna CB550, were blended with VMQ, and their mechanical and thermal properties were evaluated. Kinetics of vulcanization, static mechanical properties, dynamical mechanical analysis, thermal shrinkage, and differential scanning calorimetry were utilized. The research demonstrates that the semi-crystalline BR improves mechanical properties but induces greater shrinkage at low temperatures. Conversely, using amorphous BR provided more consistent mechanical properties across the Martian temperature range and reduced material shrink by 6.71% for samples with carbon black, by 8.36% for samples with silica, and by 11.63% for unfilled samples. Future research will be required to evaluate the impact of volume change on the sealing properties of the BR/VMQ blends.

The use of depressant additives is the most effective and cost-effective way to improve the low-temperature properties of diesel fuels, like the cloud point, cold filter plugging point and pour point. However, the effectiveness of depressant additives depends on the composition of the diesel fuel and the content of certain groups of hydrocarbons in it. In this work, the effect of adding individual hydrocarbons of various groups and structures on the effectiveness of depressant additives is studied. This study is carried out on model aromatic (toluene, tetralin) and n-paraffin hydrocarbons (cetane, heptadecane, heneicosane, docosane) in various concentrations. It is shown that the most negative effect on the depressant additives’ effectiveness is due to the content of the most polar aromatic hydrocarbons and light n-paraffins in the composition of diesel fuel, and the most positive effect is exerted by the content of heavy n-paraffins in small quantities. It is proposed to involve small concentrations (1–3% vol.) of heavy n-paraffin hydrocarbons (heneicosane, docosane) to increase the effectiveness of the depressant additive. It has been established that for the more effective action of the depressant, it is necessary to take into account the content and structure of individual hydrocarbons in the diesel fuel’s composition.

The use of depressant additives is the most common method for producing diesel fuels with improved low-temperature properties. However, the depressants effectiveness largely depends on the composition of the diesel fuel, in particular on the content of n-paraffinic hydrocarbons, which to the greatest extent determine the low-temperature properties of the fuel. The work revealed the regularities of the n-paraffins addition influence on the depressant additives effectiveness. It was found that the addition of n-paraffins to blends of diesel fuels with depressants in low concentrations (0.05–0.50% wt.) enhances the depressants effectiveness in relation to the cold filter plugging point: maximum at 6–16 °C depending on the diesel fuel sample. It is shown that the effect is observed for DF of various compositions, various depressants, and also n-paraffins of various compositions. It was established that the positive effect of adding n-paraffins increases with the heavier added n-paraffins. Recommendations have been developed for obtaining diesel fuels with improved low-temperature properties and enhancing the depressant additives effectiveness: for a sample of straight-run diesel fuel F1, it is recommended to use a blend of fuel, depressant A1 and 0.50% wt. n-paraffins, separated from heavy gasoil; for a sample of straight-run diesel fuel F2, it is recommended to use a blend of fuel, depressant A2 and 0.50% wt. n-paraffins, separated from heavy gasoil or a blend of fuel, depressant A1 and 0.05% wt. n-paraffins, separated from highly paraffinic oil fraction. The revealed patterns and the developed recommendations will allow increasing the production of low-freezing DF brands, and also offer a resource-efficient option for using heavy gas oil fractions. The results obtained in the work contribute to expanding the understanding of the mechanism of interaction between diesel fuel hydrocarbons and the active ingredients of depressant additives.

The process of hydrogen-free upgrading of diesel fraction on ZSM-5 type zeolite catalyst was implemented at the laboratory catalytic unit under the conditions of varying the process temperature. The composition and characteristics of the feedstock diesel fraction and the obtained upgrading products were investigated. The obtained diesel fraction upgrading products were tested for compliance with the standards. The directions of hydrocarbon transformations in the process of upgrading on a zeolite catalyst were considered. The influence of the upgrading process temperature on the composition and characteristics of the obtained products was estimated. For the first time, the optimal technological parameters for the implementation of the upgrading process on a zeolite catalyst from the perspective of the production of arctic diesel fuel were determined.

As high brittleness limits the application of all epoxy resins (EP), here, it can be modified by high-performance thermoplastic poly(ether nitrile ketone) containing phthalazinone structures (PPENK). Therefore, the influence of different PPENK contents on the mechanical, thermal, and low-temperature properties of EP was comprehensively investigated in this paper. The binary blend of PPENK/EP exhibited excellent properties due to homogeneous mixing and good interaction. The presence of PPENK significantly improved the mechanical properties of EP, showing 131.0%, 14.2%, and 10.0% increases in impact, tensile, and flexural strength, respectively. Morphological studies revealed that the crack deflection and bridging in PPENK were the main toughening mechanism in the blend systems. In addition, the PPENK/EP blends showed excellent thermal and low-temperature properties (−183 °C). The glass transition temperatures of the PPENK/EP blends were enhanced by approximately 50 °C. The 15 phr of the PPENK/EP blends had a low-temperature flexural strength of up to 230 MPa, which was 46.5% higher than EP. Furthermore, all blends exhibited better thermal stability.

The European Union requirements related to the quality parameters for fatty acid methyl esters (FAMEs) are gathered in the standard EN 14214:2012 + A2:2019 that also includes reference to low-temperature properties. This paper presents studies on the obtaining of modified FAMEs, featuring improved low-temperature properties. Investigated fatty acid methyl esters (FAMEs) were subjected to a solvent dewaxing process with a methyl ethyl ketone and the mixture of methyl ethyl ketone—Toluene. It was found that the application of a process carried out under conditions similar to solvent dewaxing, used as a standard procedure for oils dewaxing and slack waxes of petroleum origin deoiling usually used in refinery industrial installations, allows us to achieve the intended goal. The modification of three different types of FAME by the dewaxing process with MEK-TOL and MEK solvents allows for the improvement of low-temperature properties of the obtained modified FAME, consistent in obtaining reduced cloud points, flow points and CFPP. The tests of fatty acid profiles show a clear increase in the content of glycerides of saturated acids in the separated sludge, as compared to the charges from the dewaxing process, which confirms that the selectivity of the dewaxing process is maintained for the atypical raw material, which are fatty acid methyl esters.

The process of water-based foaming of bitumen produces binders that can be incorporated in cold recycled asphalt mixes and pavement upper structural layers made of half-warm mix asphalt prepared at 100–130 °C. During the foaming process, cold water and air act on hot bitumen (160–170 °C), which results in the explosive vaporization of water leading to changes in the binder structure. The impact of foaming on the properties of bitumen 70/100 was evaluated by investigating the binder characteristics before and after foaming. Determination of two foaming parameters, maximum expansion and half-life, was followed by measurements of penetration at 25 °C, softening point, Fraass breaking point, and dynamic viscosity at 60, 90, and 135 °C. Rheological and low-temperature tests were also performed before and after foaming bitumen 70/100. The Bending Beam Rheometer method was applied to determine the low temperature stiffness modulus. A DHR-2 rheometer was used to determine the dynamic modulus and phase angle of the tested binder. The Black and master curves before and after foaming were plotted in the 2S2P1D model and the model parameters were analysed. Analysis of the test results confirmed the effects of the foaming process on the basic, low-temperature, and rheological characteristics of the bitumen.

The tests and analyses presented in the paper are related to the 20/30, 35/50 and 50/70 penetration grade road bitumens as well as the asphalt binders obtained through modification of the 35/50 and 50/70 bitumens. The latter were modified by adding to it 3%, 5% and 7% of the Gilsonite natural asphalt and 15%, 25% and 35% of the Trinidad Epuré Z 0/8 natural asphalt. The aim of the study was to assess the changes in the functional and rheological properties of the road bitumens that were modified by adding to them the Gilsonite and Trinidad Epuré natural asphalts. The modified asphalt binders were subjected to the laboratory simulated short-term and long-term aging, where two methods, designed as part of the Strategic Highway Research Program, were used, i.e. the Rolling Thin Film Oven Test and the Pressure Aging Vessel, respectively. The study of the asphalt binders both those that were subjected to aging and those unaged includes thermal susceptibility (the Penetration Index) and resistance to cracking at low temperatures by tests carried out using the Bending Beam Rheometer. The analysis of the results revealed that the unfavourable impact of the aging process on the asphalt binder properties is limited if a suitable amount of the natural asphalt is used as a modifier.

A major global effort is currently underway to reduce dependence on petroleum products and minimize the impact of their derivatives on the environment. Plant oils are being investigated as a potential source of environmentally favorable lubricants given their combination of biodegradability, renewability and excellent lubrication performance. Low oxidation and thermal stability, poor low-temperature properties and a narrow range of available viscosities, however, limit their potential application as industrial biolubricants. The chemical modification of plant fatty acid structures has great potential for improving the physicochemical and friction-reducing properties of these compounds. This paper presents the thermo-oxidation, friction-reducing and physicochemical properties of a series of diester compounds derived from ricinoleic acid as biolubricant basestocks. The results indicated that among the synthesized ricinoleic acid-based diester compounds, octyl 10,12-dihydroxy-9-behenoxystearate 16 has the lowest pour point (−53.26 °C), while octyl 10,12-dihydroxy-9-octyloxystearate 10 has the highest onset temperature (128.98 °C) and the lowest volatile loss and quantity of insoluble deposits (68.78% and 77.25%, respectively). The friction-reducing results indicate an improvement occurred in the presence of longer mid-chain esters and an increased polarity in the ester functional group. The data indicate that some synthesized derivatives have significant potential as environmentally friendly biolubricant basestocks.

Low‐temperature magnetization of hematite within the basal plane has been studied in a collection of natural crystals by means of torque magnetometry. Comparison between the torque curves at room temperature and at 77 K allows identification of a weak ferromagnetic moment constrained within the basal plane at temperatures well below the Morin transition. Annealing the samples produces the expected reduction of the weak ferromagnetic moment, but there is also a relationship between the ferromagnetic moment before and after annealing. Low‐temperature measurements after the annealing experiment reveal the presence of a weak ferromagnetic moment that survives the annealing. This observation suggests the magnetic structure of natural hematite crystals below the Morin transition can still be a carrier of magnetization.