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In the production of sulfuric acid, sulfur cake—a waste product of the sulfur purification process—is formed in large quantities, which requires its disposal and use. For its use in composite materials, modification is necessary to convert sulfur into a polymer form. The aim of the study was to develop a method for modifying sulfur cake—a waste product of sulfuric acid production—for its disposal. Available reagents—styrene, glycerol, and oleic acid—were tested as modifiers in the work. The sample compositions consisted of 100% sulfur cake (no. 1) and its mixtures: 97% sulfur cake + 3% styrene (no. 2), 97% sulfur cake + 3% glycerol (no. 3), 97% sulfur cake + 3% oleic acid (no. 4), 95% sulfur cake + 3% styrene, 1% glycerol, and 1% oleic acid (no. 5). Modification of sulfur cake was carried out at a temperature of 140 °C for 30 min. The composition, crystal structure, and thermal properties of the samples of the original and modified sulfur cake were studied using X-ray phase and X-ray structural analyses, IR spectroscopy, differential scanning calorimetry, differential thermal and thermogravimetric analysis. The optimal modifier for sulfur cake was a mixture of styrene, glycerol, and oleic acid, which led to the formation of acetal (polyoxymethylene) and an improvement in the structure due to a decrease in the content of impurities. Modification of sulfur cake with styrene resulted in the appearance of a CAr–S bond band at 571 cm−1, and modification with oleic acid a C–S band in the region of 694 cm−1 in the IR spectra. The results of differential scanning calorimetric analysis showed an increase in the heat of fusion of sulfur by 12.45 J/g in the samples of sulfur cake modified with glycerol and styrene. Modification of sulfur cake with oleic acid and a mixture of reagents resulted in the appearance of a third peak with maxima at 244.2 and 264.0 °C, which demonstrated a significant effect of the indicated additives on the thermal behavior of the sulfur cake. Proposed schemes for modifying sulfur cake with styrene and oleic acid are presented. [ABSTRACT FROM AUTHOR]

Oil sludge is one of the main pollutants generated by the oil industry. Due to serious pollution and increasing oil production, problems arise every year in the effective treatment of oil sludge. The current study examines the composition and physicochemical characteristics of oil sludge, as well as traditional and new methods for processing oil sludge. With the tightening of environmental protection requirements, oil sludge quality reduction, recycling, and harmless treatment technologies will become necessary in the future. The primary task was to determine the composition of tank oil sludge, separate it from mechanical impurities, and study the influence of ultrasonic treatment and subsequent atmospheric distillation on the extract. The separation of the concentrate and the composition of the tank oil sludge, using an extracted mixture of hexane and benzene, are considered. The use of modern SEM methods, elemental analysis, NMR analysis, IR, ultrasound, and GC–mass spectrometry made it possible to characterize the organic part of reservoir oil sludge and its distillation products. First, 300 g of tank oil sludge was preheated and mixed with 300 mL of solvent (hexane:benzene = 1:1). After mixing with the solvent, the result mixture was filtered. Then, it was placed in an ultrasonic bath and exposed to ultrasound at a frequency of 100 kHz for 30 min. After processing, it was extracted in a Soxhlet apparatus at a temperature of 65 °C to isolate the extract. The resulting extract was analyzed on a gas chromatograph with mass detection. The composition of the extract was as follows (in %): hexane—83.99; total hydrocarbon isomers—7.12; n-hydrocarbons—2.52; benzene—6.37%. At a temperature of 85 °C, the benzene yield was 65.85%. It has been established that the fractions obtained through the distillation of oil sludge at temperatures of 65–85 °C have improved dissolving capacity. It has also been shown that the use of these fractions promotes an increase in the content of hydrocarbon isomers by 12–13% in the extract composition. [ABSTRACT FROM AUTHOR]

Since ancient times, many scientists and doctors have used various herbs to treat diseases. Conventional drugs often have side effects, and pathogens are becoming resistant to these types of drugs. In such circumstances, the study of traditional medicinal plants is an effective and logical strategy for finding new herbal medicines. One such herb is Plantago major, a perennial plant in the Plantaginaceae family that is found throughout the world. The Plantago major plant has been used as a medicine for the treatment of various diseases. Studies have shown that plant extracts of Plantago major exhibit antimicrobial, antiviral, and anti-inflammatory effects, and have wound-healing properties. This review collects and presents the results of various studies of Plantago major plant extracts with antimicrobial, antiviral, antifungal, anti-inflammatory, and wound-healing properties, which demonstrate a wide range of therapeutic possibilities of Plantago major plant extracts and have a huge potential for use as a medicinal raw material. [ABSTRACT FROM AUTHOR]

Nowadays in the world, due to the constant desire for recycling, many countries are considering the use of recycled plastics on roads. Modification of bitumen for roads in Kazakhstan is considered one of the most suitable and popular approaches. This paper presents the results of research on the modification of bitumen by recycled plastics from waste materials. The paper describes the details of the use of plastic waste as bitumen modifiers, with a specific focus on recycled plastics and how they can potentially be used to enhance bitumen performance and the road durability. The main physical and mechanical characteristics of the modified bitumen were determined after routine tests, penetration and plasticity, softening temperature, brittleness temperature on Fraas and microscopic analysis. The morphology of the modified bitumen was studied using scanning electron microscopy. The results confirm that the modified bitumen complies with the requirements for polymer-bitumen binder of Kazakhstani standards and is suitable for the production of modified bitumen by its physical and chemical characteristics. [ABSTRACT FROM AUTHOR]

In this study, we aimed to select the optimal solvents for the removal of asphaltene–resin–paraffin deposits. The effectiveness of various solvents was determined based on the asphaltene–resin–paraffin deposits (ARPDs) of the Zhanaozen (Ozen) crude oil field. These deposits affect the geological, physical, and technological conditions of the oil field, thus influencing its development. According to the results, we found that the most effective composite solvent is a composition comprising a 50% gasoline fraction and a 50% kerosene fraction. This composition showed mass loss of deposits of 97.7% and a dissolving power of 93.5 g/cm3 after 5 h. We confirmed the effectiveness of this composition by the paraffinic type of the deposits, which is explained by the high content of paraffin in the oil from the Zhanaozen field. Aromatic solvents showed a relatively low dissolving power compared with aliphatic solvents, which also confirms the low content of resins and asphaltenes in the ARPD. [ABSTRACT FROM AUTHOR]

This paper considers the effect of aging processes on viscoelastic characteristics of vacuum residue oxidation products modified with crumb rubber. Viscoelastic properties were compared to original bitumen raw material-vacuum residue and vacuum residue oxidation products during short-term and long-term aging. The complex shear modulus of the vacuum residue and its oxidation products decreased with an increase in temperature. Short-term aging resulted in increased shear modulus for all samples.The vacuum residue oxidation product modified with crumb rubber had the maximum values of the rutting parameter and fatigue parameter. There was an expansion of the temperature range of plasticity: for the vacuum residue oxidation product with crumb rubber, its value was 67.2 °C. The curves of the black diagram of the modified vacuum residue oxidation product are shifted towards smaller phase angles with the increase in the shear modulus, which indicates the increase in the stiffness and elasticity of the rubber bitumen binders. The vacuum residue oxidation product modified with crumb rubber corresponded to the rubber bitumen binder of the grade RBB 60/90, according to its physical and mechanical indicators. [ABSTRACT FROM AUTHOR]

Contamination of soil and water with petroleum during its extraction, collection, transportation, storage and preparation occurs frequently, and purification of oil spills is one of the pressing environmental problems of oil producing organizations. There are a large number of methods for utilization oil spills. The sorption method in combination with bioremediation is capable of effectively purification of petroleum contaminated soils. The paper shows the possibility of using a carbonized mixture of shungite from the Koksu deposit (Kazakhstan) with rice husk as a sorbent and carrier of microorganism strains. The physicochemical properties and elemental composition, as well as the microstructure of carbonized samples were established. The maximum sorption capacity of carbonized sorbents when purifying the soil samples from oil from the Karazhanbas field was 1.86 g/g after 60 days. The carbonized samples with microorganism strains immobilized on them showed a degree of oil destruction reaching 90%. [ABSTRACT FROM AUTHOR]

In the paper, bulk property and chemical composition of Kazakhstan vacuum residuum were characterized. Sulfides and thiophenes were selectively isolated from the residuum and characterized by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Molecular weights of the sulfur compounds were varied from 150 to 800 Da and S1, S2, O1S1, O2S1, N1S1 class species were assigned in the heavy oil derived methylsulfonium. Vanadyl porphyrins characterized by positive-ion electrospray ionization and FT-ICR MS, which showed that etioporphyrins (ETIO) (CnH2n-28N4V1O1, corresponding to DBE = 17) and deoxophylloerythroetioporphyrins (DPEP) (CnH2n-30N4V1O1, corresponding to DBE = 18). It should be noted that the vanadyl porphyrins were most abundant. [ABSTRACT FROM AUTHOR]

This study focused on the purification of ethylene from acetylene using a catalyst made of cobalt deposited on a carbon-containing material, such as clay. Cobalt catalysts with different mass fractions were carbonized at a temperature of 550 °C, activated with 5% and 10% nitric acid and tested for the hydrogenation of acetylene to ethylene. The physicochemical properties were investigated by means of X-ray powder diffraction (XRD), scanning electron microscope (SEM) and TG/DSC. The reaction products were analyzed using a Chrom-3700 gas chromatograph and gas chromatography–mass spectrometry (Agilent 7890A/5975C). The conversion of a 7% Co/CL-10 catalyst, carbonized at 550 °C, was 82% at 100 °C, and reached 95% at 140 °C. Side reactions were activated when the temperature rose above 140 °C, which reduced the ethylene yield. The carbonized catalysts exhibited more activity than traditional impregnated catalysts that had not been subjected to carbonization. This paper outlines a simple method for preparing Co/CL-10 catalysts with high catalytic activities for the selective hydrogenation of acetylene, using the carbonization process on a chemically-activated carrier clay. [ABSTRACT FROM AUTHOR]

Featured Application: Modification of the thermorheological properties of bitumen binder by incorporation of alkylated silica nanoparticles. A study on the effect of silica nanoparticles (SNPs) dispersion in bitumen is herein reported. First, the size of the nanoparticles was finely tuned by controlling the experimental conditions during their synthesis, obtaining spherical SNPs with diameter ranging from 95 up to 900 nm. Subsequently, SNPs were embedded with peripheral amine groups by using APTES (3-aminopropyltriethoxysilane) as functionalized agent (NH2@SNP), and ultimately long alkyl chains were grafted by reacting the free amine with an alkylated aldehyde (C14N@SNP). All SNPs (ca. 1 wt%.) were dispersed in bitumen to probe their effect on the rheological properties of bitumen. No significant change in the thermorheological properties of bitumen was observed upon varying the size of the SNPs. Slight improvement was observed when using NH2@SNPs, while the best results were obtained by using C14N@SNPs, showing the crucial role that hydrophobic substituents play in bitumen binders which leads to significant improvements. [ABSTRACT FROM AUTHOR]

Demetallization and desulfurization of vacuum residuum from the Pavlodar Petrochemical Plant (Kazakhstan) was carried out by adsorbents based on zeolite modified with titanium compounds and vanadium oxide. The process was carried out at a temperature of 320-360°C for 1 to 3 hours at atmospheric pressure. The results of determining the physico-chemical characteristics of the modified adsorbents showed that, after modification, their specific surface area increases, but the specific pore volume decreases. The maximum degree of demetallization is observed when using an adsorbent based on zeolite modified with titanium oxides and vanadium oxides. The change in the structure of vanadylporphyrins in vacuum residuum composition after the demetallization process is determined. After demetallization etioporphyrins have C27-C32 with a center of mass at C29, phylloporphyrins have C28-C34, after treatment at 360 °C, the center of mass shifts towards an increase in the number of carbon atoms C31. [ABSTRACT FROM AUTHOR]

The paper presents the results of thermal cracking of natural bitumens of the Beke and Munaily Mola oil sand deposits (Kazakhstan). The data obtained show that the high-molecular components of the bitumen of the Munaily Mola deposit are more easily cracked than those of the Beke deposit. The cracking of natural Beke bitumen in a medium of water vapor, acetonitrile and isopropanol is studied at different temperatures and pressures. The effect of the heterogeneous additive - nano-sized copper (II) oxide on the cracking efficiency of natural bitumen components is identified. The total yield of gas and coke is 3.2%, while the distillate fractions is 40.8 mass % in case of cracking of the Beke natural bitumen in a flow reactor. [ABSTRACT FROM AUTHOR]

The purpose of the work is demetallization and desulfurization of heavy oil residues using adsorbents. Optimal parameters of the demetallization and desulfurization processes of heavy vacuum fraction of Pavlodar Petrochemical Plant LLP in the presence of a zeolite adsorbent containing vanadium oxide xerogel were established: temperature 340 °C, pressure 1 atm., bulk feed rate 1 h−1. As a result of the process the extraction degree of vanadium, nickel and iron were 90, 70 and 60%, respectively, and the sulfur content decreased from 1.97 to 1.36%. Composition of the chemical adsorbent for demetallization and desulfurization of heavy vacuum fraction is established, too. Content of vanadium, iron and sulfur increase in composition of the adsorbent after treatment of heavy vacuum fraction, which confirms its high adsorption capacity regarding to metals and sulfur. [ABSTRACT FROM AUTHOR]