Yield Of Fraction Research Articles

Development of correlations between deasphalted oil yield and Hansen solubility parameters of heavy oil SARA fractions for solvent deasphalting extraction

Solvent deasphalting (SDA) is a heavy oil upgrading process that selectively extracts deasphalted oil (DAO) and rejects asphaltenes. In this study, a quantitative analysis was conducted to predict DAO yields in the SDA process using relative energy difference (RED); the RED was calculated from Hansen solubility parameters (HSPs) of the feedstock and extraction solvent along with the extraction conditions, such as temperature and solvent-to-oil ratio (SOR). SDA extraction experiments were performed in a continuous bench-scale unit using vacuum residue (VR) and a mixture of bunker C fuel oil (BC) and VR as feedstocks. The HSPs of saturate, aromatic, resin, and asphaltene fractions derived from the VR and BC were measured using solubility tests, wherein the fractions were dissolved in 37 different solvents. Finally, simple and accurate correlations between the DAO yield and corresponding modified RED were acquired and used to explain the effects of temperature and SOR on the DAO yield.

ИССЛЕДОВАНИЯ ВЛИЯНИЯ ТЕХНОЛОГИЧЕСКИХ ПАРАМЕТРОВ НА ГРАНУЛОМЕТРИЧЕСКИЕ ХАРАКТЕРИСТИКИ СУБМИКРОННОГО ОКСИДА АЛЮМИНИЯ В α-ФОРМЕ

Experimental studies of the influence of technological parameters of grinding alumina raw materials in a ball mill on the kinetics of the grinding process and the granulometric characteristics of activated alumina in the α-form have been carried out. It is found that the use of spherical grinding bodies leads to the formation of a specific four-modal granulometric composition with maxima: 0.5; 4.0; 50.0 and 400.0 microns, respectively. The disadvantage of using spherical grinding bodies is the uneven distribution of the introduced intensifier additive (PEG), which in turn causes adhesion of fine particles and the appearance of aggregates. This is especially pronounced at n = 100 rpm. When using grinding bodies of cylindrical shape, on the contrary, there is a tendency towards a bimodal nature of the distribution of particles with maxima in the regions of 0.4 and 4 μm, respectively, regardless of the rotation speed of the drum (n). The use of cylpebs does not provoke agglomeration of the fine particle fraction, which is observed in the case of spherical grinding bodies. When analyzing the kinetics of grinding alumina raw materials, two main stages of the process are identified. The first stage corresponds to the active fragmentation of large initial aggregates into constituent crystallites by the cleavage mechanism. The second stage corresponds to a change in the grinding mechanism from crushing to abrasion. It is found that carrying out the grinding process for 10 hours using cylindrical grinding bodies at n = 100 rpm and φ = 0.35 provides a high yield of the submicron fraction of the target product (1 μm) - up to 20 wt. %.

Investigation of the process of extraction of a highly starchy fraction of rye flour by air classification

The article provides an overview of the current state of the application of solid-phase methods for separating the structure of grain and leguminous raw material into constituent components, as one of the most relevant areas of environmental protection and reducing the amount of wastewater from enterprises processing agricultural raw materials. The main direction of research on the production of protein concentrates from leguminous raw materials (peas, beans, chickpeas, lupine) by the method of air classification is noted. Among grain crops, rye stands out as having a more balanced amino acid composition compared to wheat and the largest starch grains up to 60 microns, which improves the aero-dynamic separation of grain flour into protein and starch fractions. Тherefore, rye flour was the object of research in this work. The research area included the development of a method for determining the starch content in the heavy fraction of rye flour from the yield of its light protein fraction and its starch content using an installation with variable parameters of a two-chamber disperser and a vortex classifier. The results of experiments on the separation of the mass of the initial rye flour into heavy starch and light protein fractions with a given ratio of starch and protein are theoretically justified and experimentally confirmed. The dependences of the starch content in the heavy fraction on the number of cycles of its recycling are established. With variable parameters of grinding rye flour, determined by the speed of the working bodies of the dispersant from 70 to 100 m/s, the time of grinding and recirculation of the heavy fraction of 30 s and the tangential speed of the classifier rotor of 15 m/s, stable results were obtained for the separation of starch and protein. Тhe yield of the heavy fraction of 72 % with a starch content of 85 % and the yield of the light fraction of 28 % with a mass fraction of protein of at least 26 %.

Effect of varying fraction of polypropylene waste on co-pyrolysis of Delonixregia and Polyalthialongifolia leaves

Non-catalytic co-pyrolysis of Delonix Regia (DR) wood and Polyalthia Longifolia (PL) leaves and varying fractions of polypropylene (PP) has been carried out at 600 ​°C in a tubular reactor. The fractions of PP varied in order to have 0 ​wt.%, 10 ​wt.%, 30 ​wt.% and 50 ​wt.% of it in the feed while the composition of DR and PL maintained constant and equal to each other so that to study the effect of PP on co-pyrolysis of two lignocellulosic biomass waste materials. The feed materials, along with the products (bio-oil and biochar) have been extensively characterized for their physicochemical and fuel properties. In addition, extensive advanced material characterization techniques such as Fourier Transform Infrared Spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), etc. have been utilized for analysis purposes. The properties of bio-oil reported in this work are of the organic phase only of the liquid product. The average calorific value of organic fraction of bio-oil is increasing from 22.556 ​MJ/kg to 34.06 ​MJ/kg with increasing wt.% of polypropylene (PP) in co-feed from 0 ​wt.% to 50 ​wt.% respectively, while the calorific value of biochar is showing mixed trend. Density of organic phase decreases from 973 ​kg/m3 to 816 ​kg/m3 with increasing the fraction of PP, while pH display opposite trends i.e., increasing from 4.31 to 4.97 which are close to commercial fuel properties. FTIR confirm the presence of functional groups of alkanes, aromatics, alcohols, phenols, aliphatic, ketone, ethers, etc. in organic fraction of bio-oil; and also confirmed by proton NMR. Further it is also confirmed that fraction of alkanes and aliphatic in bio-oil samples increases with PP fraction in the co-feed. The main finding of this work indicates that the fraction of PP in co-feed improved the physicochemical, chemical and fuel potential of the organic phase of liquid product. However, the trend of yield of organic fraction of liquid is not as expected and the reason could be the presence of leaves of PL because often the yield of liquid product is very low when leafy biomass used as feed.

Hydrotropic Cloud Point Extraction of Lipids from Microalgae: A New Pathway for Biofuels Production

The solubilization of fatty acids by small amphiphiles such as butyl ethylene glycol, butyl or pentyl diethylene glycol, and hexyl triethylene glycol, also called hydrotropes, was demonstrated by the determination of their phase diagram. They were thus applied for the passive extraction at room temperature of lipids from Dunaliella salina microalgae. The extraction yield of the lipidic fraction (mainly coming from glycolipids), could reach up to 81%, depending of the nature of the hydrotrope and its concentration. In addition, their cloud point properties allow the easy separation of the organic fraction, and their low boiling points allow their recovery with a lower energetic cost than the energetic content of the solubilized lipids. They can also directly be used for the transesterification of the lipids to give the corresponding fatty esters, which may be used as biofuels.

Sowing date as a response to ecological conditions in maize seed production

The environment protection, energy, and resources preservation are especially pronounced under present climate changes. In agriculture, these changes are recognised as drought, high temperatures, occurrence of stormy winds and hail. The aim of this study was to determine variations in seed morphology that are a result of different sowing dates in relation with agro- ecological conditions of maize (Zea mays L.) cultivation. The material used for the study encompassed three inbred lines (G1, G2, G3) sown every 10 d on five sowing dates (T1, T2, T3, T4, T5) starting from 1 April to 10 May, during 2 yr (Y1: 2018, Y2: 2019). The following physical properties of seeds were estimated: width (W), length (L), thickness (Tk), ratio of small (SF) to large fraction (LF) and grain yield (GY). The width was the highest in all three inbreeds on T4 (1.00, 1.03, 0.99 cm, respectively); T5 was the least favourable date for L (1.09, 1.12, 1.09 cm, respectively) while Tk was the lowest in G1 (0.51 cm) and G2 (0.51 cm) sown on T1. The most significant differences in the formation of physical properties occurred in seeds sown on T5 (p ≤ 0.05). The highest differences were observed in width between T5-T4 (-0.223 cm), in length between T5-T2 (-0.309 cm) and in thickness between T5-T3 (-0.129 cm). Later sowing dates favoured LF (85.2%) in comparison to SF (14.7%). Seed size variability participated with 50% in yield formation (R2 ≥ 0.5).

Thermocracking of a heavy fraction of the oil residue in a mixture with shale

The process of tar thermal cracking in a mixture with crushed oil shale to obtain components of motor fuels and raw materials for the process of thermal cracking is investigated in this paper. The optimization results of technological parameters (shale concentration, temperature, and duration) are presented and the material balance (mass.%) of the process is made. It was found that during single-stage processing under relatively mild conditions (5 MPa, 425C, feed space velocity of 1.0 h-1), a deep destruction of tar is achieved (the yield of the gasoline fraction from boiling point to 200C is ~12 wt.%; medium distillates with boil. point 200370C-43-44 mass.%; raw materials for thermal cracking with boil. point above 370C ~15-16 wt.% on per the original tar). The generating coke-like products and the V and Ni contained in the raw materials are deposited on the mineral part of the shale and removed from the reaction zone with the liquid products of the process.

Hydrodynamic activation of heavy oil residues

Objectives. Recently, there has been a tendency to increase the volume of high-viscosity heavy oils in the total volume of oil produced. The processing of these oils requires new technological approaches. This task is closely related to the need to increase the depth of oil refining. Among the approaches proposed to solve these problems, mechanochemical activation, which is based on the cavitation effect produced by ultrasonic or hydrodynamic methods, has been suggested. This study evaluated the effects of cavitation in increasing the depth of oil refining.Methods. Straight-run and “secondary” oil products were used as raw materials: vacuum gas oil, catalytic cracking gas oil, and fuel oil. Activation was carried out in a high-pressure disintegrator. The principle of operation was to compress the oil product and then pass it through a diffuser. When the oil was passed through the diffuser, there was a sharp pressure release to atmospheric pressure, which caused cavitation in the hydrodynamic flow. The pressure gradient on the diffuser and the number of processing cycles ranged from 20 to 50 MPa and 1 to 10, respectively. The density, refractive index, and the fractional composition of petroleum products were determined using standard and generally accepted methods.Results. This paper reports the influence of mechanochemical activation of petroleum products on their physical and chemical characteristics. An increase in the pressure gradient and the number of processing cycles leads to a decrease in the boiling point of the petroleum products and their density and an increase in the yield of fractions that boil off below 400 °C. The yield of the fractions with boiling points of 400–480 °C and the remainder were reduced. The density and refractive index of fractions with boiling points up to 480 °C decreased, and the density of the residue increased. The effects of cavitation (an increase in the yield of fractions with boiling points up to 400 °C and a decrease in the density of the petroleum products) increased with increasing pressure gradient and the number of processing cycles.Conclusions. The changes in the density, boiling point, and the yield of fractions increased with increasing the pressure from 20 to 50 MPa and the number of hydrodynamic cavitation cycles from 1 to 5. Increasing the number of processing cycles to more than five had little additional effect. The effects of cavitation increased with increasing initial density of the oil product. The average molecular weight of these fractions was estimated from the densities and boiling points of individual fractions of the petroleum products. The calculation confirmed the assumption regarding the course of cracking reactions of petroleum products under the influence of cavitation and indicates the course of the compaction processes.

Effect of cell density on the biological titer and yield of 146S fraction of foot-and-mouth disease virus O in cell suspension

Foot-and-mouth disease (FMD) is a highly infectious disease of cattle and other cloven-hoofed animals, causing huge economic losses annually worldwide. This disease is endemic in Pakistan where the serotypes of the foot-and-mouth disease virus (FMDV) are A, O and ASIA-1. At present, trivalent FMDV vaccines are being used to prevent FMD but the current production process is laborious and is unable to fulfill the needs of the meat and dairy industries. To meet the vaccine needs of Pakistan, the conventional method of using adherent cell lines to produce the vaccine could be replaced by suspension cell cultures which produce higher yields in less time and less volume. Therefore, the aim of this study was to investigate and optimize some of the factors that affect viable cell density and subsequent virus yield. The relationship between the yield of the 146S fraction and the TCID50 of the virus preparations obtained was also evaluated as a mean to control and check the quality of the vaccine product. The results provided optimized conditions for vaccine production using cell suspensions and showed that there was a linear relationship between TCID50 and 146S fraction yield. Either TCID50 or the 146S fraction yield, or both could be used as parameters for quality monitoring during vaccine production. Using TCID50 reduced the number of steps involved in virus production while measuring 146S fraction yield was useful for quality control. However, more studies are required to evaluate the relative effectiveness of vaccines produced by virus cultures using either TCID50 or 146S fraction as quality monitoring tools.

Dairy productivity of holstein cattle with different genotypes of the kappa-casein gene (CSN3)

The purpose of research was to study the polymorphism of the CSN3 gene and its effect on milk yield, fat and protein mass fractions in milk, as well as on the lactation curve characteristics in the first lactation of Holstein cows. The experiment was carried out on the biological material of 146 cows of of Integrated Agricultural Production Centre “Stud farm named after Lenin” of the Atninsky district of the Republic of Tatarstan in the laboratory of agrobiological research of Tatar Research Institute of Agriculture of FRC KazanSC of RAS. DNA diagnostics by PCR-RFLP method of the CSN3 gene testified that the livestock under study is genetically diverse. The herd contains animals of all genotypes: АA – 41,1%, АВ – 47,9%, ВВ – 11,0%. The frequency of occurrence for allele A was 0.651, for allele B – 0.349. The genetic equilibrium in the population is not disturbed, the chi-square criterion is below the critical value. The analysis of milk productivity indicators of cow-heifers with different genotypes of the CSN3 gene shows the superiority of animals with the AB genotype in milk yield per standard lactation (6908.5 kg), with the BB genotype in the content of the protein mass fraction (4.05%) and protein yield (267.8 kg). Individuals with the AA genotype are characterized by an increased mass fraction and milk fat yield (3.65% and 244.4 kg). Cows have different lactation curves depending on the genotype of the CSN3 gene.

Steam explosion pretreatment of coffee husks: a strategy towards decarbonization in a biorefinery approach

AbstractBACKGROUNDCoffee husks (CH) are an abundant lignocellulosic residue that can be converted into biofuels and bioproducts through sustainable and economical processes in a biorefinery approach. For that, steam explosion (SE) pretreatment stands out as a technique to overcome its recalcitrant nature and enable byproduct valorization. In this study, solid and liquid fractions were separated after pretreatment for saccharification and biogas production, respectively. The research relevance relies on the contribution to environment decarbonization and monetization of decarbonization credits (CBIO) generated from the production of renewable fuel from waste biomass under different operational conditions (with and without pretreatment).RESULTSLiquid hydrolysate generated by SE condition at 210 °C and 15 min led to the highest biomethane production (292 NmL CH4 g CODfed−1). Similarly, high‐severity pretreatment also favored the enzymatic hydrolysis yield of the solid fraction (49%). In terms of environment decarbonization, SE promoted not only a lower carbon intensity when compared to the process without any pretreatment (3.8 vs. 6.4 g CO2eq MJ−1), but also increased the monetization of decarbonization credits by 175%, which represented a potential revenue of US $1 481 330.CONCLUSIONHigh temperatures of SE pretreatment of CH at 210 °C were able to promote biogas production and fermentable sugars. In addition, the process reduced carbon emissions and increased the revenue from CBIO commercialization. Therefore, SE proved to be a sustainable and economic alternative for consideration in new green businesses from lignocellulosic residues such as CH. © 2021 Society of Chemical Industry (SCI).

Determination of optimal conditions for processing oil bottom sediments using electrohydraulic effect

Currently, there is an interest in effective technologies that cause minimal environmental harm, have low financial costs and allow you to obtain products with high added value. One of the ways to increase the yield of light and medium fractions from oil bottom sediments is to use the electrohydraulic effect. The electrohydraulic phenomenon is a new industrial method of converting electrical energy into mechanical energy, which occurs without the influence of intermediate mechanical links, with high efficiency. Statistical processing of experimental data was carried out with the identification of the optimal mode of the electrohydraulic effect on the destruction of the oil bottom sediment. The influence of various factors is shown (duration of contact, distance between electrodes, amount of added catalyst, capacitance of capacitor and value of applied voltage). The use of the generalized equation made it possible to determine the following optimal conditions for the destruction of the oil bottom sediment using electrohydraulic treatment: duration 7 min, distance 8 mm, amount of added catalyst 1.5 %, capacitance 0.3 μF, applied voltage 14 kV. In terms of the significance of the coefficient (tr), it should be noted that the dominant factors are the distance between the electrodes and the amount of added catalyst. The individual chemical composition of the light and medium fractions of the original oil residue and the processed oil residue was determined. Comparison of the individual chemical composition of fractions up to 200 °С and 200–300 °С, obtained from the oil bottom sediment and from the hydrogenated product, allows to conclude that the electrohydraulic effect has an effective effect on the destruction of the organic mass of the oil bottom sediment. The optimal conditions for electrohydraulic treatment of the oil residue aere established and it is shown that it is possible to utilize the oil bottom sediments

Effects of Lower Temperature on Expression and Biochemical Characteristics of HCV NS3 Antigen Recombinant Protein

The nonstructural antigen protein 3 of the hepatitis C virus (HCV NS3), commonly-used for HCV ELISA diagnosis, possesses protease and helicase activities. To prevent auto-degradation, a truncated NS3 protein was designed by removing the protease domain. Firstly, it was overexpressed in E. coli by IPTG induction under two different temperatures (25 and 37 °C), and purified using affinity chromatography to attain homogeneity above 90%. The molecular mass of purified protein was determined to be approx. 55 kDa. While lowering the temperature from 37 to 25 °C, the yield of the soluble fraction of HCV NS3 was increased from 4.15 to 11.1 mgL−1 culture, which also improved the antigenic activity and specificity. The protein stability was investigated after long-term storage (for 6 months at −20 °C) revealed no loss of activity, specificity, or antigenic efficacy. A thermal stability study on both freshly produced and stored HCV NS3 fractions at both temperatures showed that the unfolding curve profile properly obey the three-state unfolding mechanism. In the first transition phase, the midpoints of the thermal denaturation of fresh NS3 produced at 37 °C and 25 °C, and that produced after long-term storage at 37 °C and 25 °C, were 59.7 °C, 59.1 °C, 55.5 °C, and 57.8 °C, respectively. Microplates coated with the fresh NS3 produced at 25 °C or at 37 °C that were used for the HCV ELISA test and the diagnosis outcome were compared with two commercial kits—Abbott HCV EIA 2.0 and Ortho HCV EIA 3.0. Results indicated that the specificity of the HCV NS3 produced fresh at 25 °C was higher than that of the fresh one at 37 °C, hence showing potential for application in HCV ELISA diagnosis.

FRACTIONATION OF OIL OF A NEW LINE OF SUNFLOWER SEEDS

The main methods of obtaining fractionated oils and fats have been analysed. They involve three essentially different processes of fractionation of acylglycerols: dry fractionation, aqueous fractionation with a detergent, and solvent fractionation. Considerable attention has been paid to determining the conditions for fractionation of sunflower oil modified in its fatty acid composition. It has been emphasised that using stearic sunflower oil free from trans fatty acids as a source of fats is a topical task. The practical importance of complex research on fractional crystallisation of stearic sunflower oil has been substantiated. The experiments have allowed establishing the fatty acid and triacylglycerol composition of the oil of the new line of sunflower seeds of the saturated type Х114В (stearic type). The structure of its acylglycerols has been mathematically determined. Data have been obtained that besides the increased stearic acid content (9.1% of the total fatty acids), the oil under study also contains a significant amount of the disaturated–monounsaturated fraction of acylglycerols (6.16%). The method of fractionating sunflower oil of the stearic type, which has been scientifically substantiated, involves one-stage fractional crystallisation from the melt. The conditions of fractional crystallisation have been experimentally established: the crystallisation temperature range (+6 – +9°С), the crystallisation time (38 days), and the cooling rate (≈0.0051°С/s). The target fraction of sunflower oil of the stearic type has been obtained. It differs from the original oil in its fatty acid and acylglycerol composition. The yield of this oil fraction was 24.57%. It has been found that the fatty acid composition of this fraction has a content of palmitic acid increased by 0.9% and that of stearic acid higher by 3.3%, while its linoleic acid content decreased to 41.9%. The total amount of saturated fatty acids in the target fraction sample is 19.8% of all fatty acids. It has been found that the proportion of disaturated–monounsaturated acylglycerols in the target fraction increases by 3.27%. The resulting target fraction will be useful in flour and confectionery technologies as a substitute for fats containing trans fatty acids

Catalytic Co-Cracking of Used Cooking Oil Methyl Ester and Polystyrene Waste for Gasoline-Rich Biofuel Over Mesoporous Al-MCM-41 Catalyst

Used cooking oil and packaging foam are typical waste materials that are abundantly available as household and fast food restaurant waste with high energy content, thus representing potential feedstock for conversion into an alternative energy source. In this study, catalytic co-cracking was examined at 300°C in atmospheric pressure to generate fuel products with gasoline-like properties from a mixture of used cooking oil biodiesel and polystyrene pyrolysis oil. Mixture of ceramic powder and Al-MCM-41 was used as catalyst in comparison to a pristine mesoporous aluminosilicate material. The product distribution of produced biofuel wes analyzed by gas chromatography – mass spectrometry. Experimental results exhibit that catalytic co-cracking process generated up to 64,6 – 67,2% yield of liquid hydrocarbon. The product distribution and the quality of the resulting biofuel were significantly affected by Si/Al ratio of the catalyst. Pristine Al-MCM-41 with lower Si/Al ratio was more favored for the enrichment of gasoline range fraction (C7–C12) which give 88,98% yield, while Al-MCM-41/ceramic with higher Si/Al ratio only give 32,84% yield of gasoline fraction. Moreover, lower oxygenate compound with better stability of biofuel was also obtained using pristine Al-MCM-41 catalyst. The produced biofuel blend by both catalysts indicated promising physical properties including higher calorific value (53,2 and 52,4 MJ/kg) and higher-octane number (RON 99,8 and 95,5) than commercial gasoline.

Study of preceramic compositions based on modified polycarbosilane and polyorganosilazanes

Ceramic matrix composites (CMC) exhibit increased crack resistance and resistance to mechanical and thermal shock impacts retaining at the same time the valuable properties of monolithic ceramics. Therefore, they are widely used as parts of heat-loaded elements of aviation and rocket technology, in nuclear power industry, etc. LPI-method (liquid polymer infiltration) of CMC production is based on the impregnation of a skeleton of ceramic fibers with an organosilicon polymer, formation of a preceramic matrix by polymer technology, and subsequent high-temperature pyrolysis resulting in formation of a reinforced ceramic matrix. Ceramics obtained from polymer precursors have a predominantly amorphous structure which determines its high thermal stability. Moreover, introduction of the nanosized particles of carbides, borides and nitrides of refractory metals (Zr, Ti, Hf) into the matrix of a ceramic composite stabilizes its amorphous structure up to temperatures of 1500 - 1600°C. We present the results of studying the preceramic compositions based on polycarbosilane and polyorganosilazanes modified with Hf and Ta atoms. It is shown that introduction of the modifying additives Hf and Ta into the polyorganosilazane composition shifts the curing interval of the compositions towards lower temperatures. The yield of the gel fraction is 73.3 and 82.7 wt.%, respectively. The weight loss of pyrolysate samples heated to 1400°C in air does not exceed 0.5%. The physical and mechanical properties, as well as the thermal oxidative stability of novel ceramic composite materials obtained on the base of the studied compositions and carbon reinforcing filler are analyzed. It is shown that the density of CMC samples increases by 1.5 times with an increase in the number of impregnation cycles and reaches the maximum value of 1950 kg/m3 with five impregnation cycles of the filler with a composition based on polyorganosilazane modified with Ta. The results obtained can be used in the development of new CMCs.

Catalytic deoxygenation by H2-free single-step conversion of free fatty acid feedstock over a Co-Ag carbon-based catalyst for green diesel production

A family of activated carbon-supported Co-Ag catalysts, synthesised through incipient wetness impregnation, have been evaluated for the deoxygenation of palm fatty acid distillate (PFAD) and inedible feedstocks (jatropha oil and waste cooking oil) to green diesel. High deoxygenation efficiency and conversion of PFAD to hydrocarbon liquid products through decarboxylation/decarbonylation (deCOx) is observed, with Co(10wt.%)-Ag(5−20wt.%)/AC exhibiting the greatest hydrocarbon (C8–C20) fractions yield of 92 % and 95 % (C15+C17) selectivity after 120 min reaction at 350 °C. These results suggested the synergistic effect between the active metals, Co-Ag, and the activated carbon support, creating acid-base Brönsted sites, which significantly facilitated the selective deCOx pathway of the fatty acid. The catalyst Co(10wt.%)-Ag(10wt.%)/AC was capable of deoxygenation the PFAD over eight cycles. Thus, it can be believed a potentially promising catalyst for the production of green diesel, at the same time providing economic opportunities and added value to the palm oil industry.

Crack formation dynamics investigation of in a solid body under the surfactant influence

A method for estimating crack formation in a solid is proposed. The necessity the crack formation dynamics investigation is substantiated. Based on the Rebinder effect, a method for controlling the cracking nature using surfactants is proposed. The destruction by impact and explosion of samples pre-treated with water and surfactant is considered. It is established that pre-treatment of glass plates with surfactant solution shows a more uniform cracks distribution on impact, which may be the basis for the assumption that the surfactants use in blasting will significantly improve the crushing quality and reduce the oversized fractions yield. When examining the samples, which were saturated with surfactant solution, it is seen that the cracks system only increased after the explosion, small cracks appeared, which connect large ones. In the case of water use, we also see an increase in cracking, but it is not as intense and uniform as in the case of surfactants previous use. This result also confirms the fact that the pre-saturation of the medium with a surfactant solution before the pulse loads contributes to a more uniform crushing in the future and provides a basis for experiments on three-dimensional models in this direction.

Non-Catalytic Dissolution of Biochar Obtained by Hydrothermal Carbonization of Sawdust in Hydrogen Donor Solvent

The production of fuel hydrocarbons from CO2-neutral raw materials is a promising task at present. The thermal dissolution of biochar obtained by the method of hydrothermal carbonization of sawdust was studied. The dissolution of biochar in tetralin (hydrogen donor solvent) was studied at different temperatures (350–450 °C) and with two types of dilution of the mixture with tetralin: 1/3 and 1/4. The process proceeded without a catalyst. It was found that the samples subjected to thermal dissolution at temperatures of 425–450 °C had the highest conversion and yield of liquid products. The reaction temperature also had a significant effect on the composition of liquid products. It was found that an increase in the reaction temperature led to a significant increase in benzenes, both in the direct and in the hexane fraction. A benzene yield of more than 50% was observed for both fractions at a temperature of 450 °C. It was also suggested that the possible positive effect of abietates on the homogenization of the reaction mixture contributed to high conversion in the process. The biochar/tetralin ratio effects the yield and composition of the liquid products as well. An increase in the tetralin concentration in the mixture during thermal dissolution led to an increase in the conversion and yield of hydrocarbon fractions for fuel purposes. This is undoubtedly due to the large amount of elemental hydrogen involved in the hydrogenation of the reaction mixture.

The Masteralloy Concept for Sintered Steels - New Impetus for a Classical Approach

Among the various alloying techniques used in powder metallurgy, the masteralloy concept has been known for a long time. However, its use for production of ferrous precision parts has been hampered by several obstacles such as poor output of the useful fine fractions, high tool wear and slow homogenization kinetics of the alloy elements in the matrix. On the other hand, the masteralloy concept is particularly interesting for introducing cost-effective alloy elements such as Cr, Mn and Si since the masteralloy approach at least alleviates the problems caused by the high oxygen affinity of these elements. In the present study it is shown that recent developments have given a boost to this classical concept, one of these developments being powder manufacturing by high pressure water atomization which dramatically increases the yield of fine masteralloy fractions. The other progress is availability of thermodynamic software that enables defining masteralloy compositions with low melting range and thus fast homogenization also at moderate sintering temperatures. Combined, these new developments open the door for implementation of the masteralloy route in large scale PM parts production.