Stirring Intensity Research Articles

Improving compositional homogeneity of CF53 steel products by modifying their solidification structure and F-EMS intensity

In this article, based on the mechanism of stirring induced solute washing, the solidification characteristics of CF53 steel for camshafts were systematically studied through industrial casting tests and numerical simulations, focusing on the impact of solidification structure and final electromagnetic stirring (F-EMS) on solute distribution homogeneity in the core area of the bloom casting. The results indicate that excessive columnar crystal development, coupled with inappropriate use of F-EMS, can lead to significant negative segregation in the bloom, resulting in the formation of “white bands” in the following rolling bar products. Compared with weak stirring, strong stirring can affect solutes at deeper levels between dendrites. By reducing superheat and casting speed, expanding the equiaxed crystal zone in the bloom's centre, and carefully controlling the stirring intensity of F-EMS to position the molten steel washing in the equiaxed crystal zone, along with maintaining a maximum tangential velocity of 0.0041 m/s, a substantial improvement in solute distribution homogeneity within the bloom's core area was achieved. The carbon range can be reduced from 0.093% to 0.032%. These findings offer a theoretical foundation and practical suggestions for enhancing the quality of CF53 steel bloom castings and their hot-rolled bar products used in camshaft manufacture.

Evaluating the Potential of Modified Mango Leaves as a Biosorbent for the Removal of Mercury (II) Ion and Congo Red from Wastewater

The discharge of harmful metallic elements from industrial byproducts has resulted in notable environmental and public health risks. The aim of this study was to investigate the effectiveness of mango leaves as a cost-effective adsorbent in eliminating Hg (II) ions from industrial effluents. Experimental procedures were carried out under controlled conditions at ambient temperature to evaluate the influence of pH, contact duration, initial metal levels, adsorbent quantity, and temperature on the adsorption mechanism. The most favorable pH for optimal Hg (II) ions adsorption was identified at pH 7. The adsorption process displayed swift kinetics in the initial 30 minutes of contact, leading to a removal rate exceeding 90%, with equilibrium achieved after 70 minutes of stirring. Analysis of kinetics revealed a significant correlation coefficient for a pseudo-second-order kinetic equation. The absorption of Hg (II) ions escalated with increased stirring intensity and decreased adsorbent amount. The interaction between Hg (II) ions, Congo red, and mango leaves was analyzed employing Langmuir, Freundlich, and BET isotherm models. The equilibrium data was best fitted by the Langmuir model, presenting a correlation coefficient of 0.98 and a maximum adsorption capacity of 28.40 mg/g. These results underscore the potential of mango leaves as an affordable bio adsorbent for addressing heavy metal pollution in wastewater.

Insight into the Effect of Nanobubbles on Fine Muscovite Powder Flotation in Different Dodecylamine Concentrations and Stirring Intensities: Kinetics and Mechanism

Flotation-introduced nanobubbles were expected to be an efficient and economical method to recover fine muscovite. This study aimed to explore the mechanism of the change appearing in flotation after introducing nanobubbles through micro-flotation, particle vision and measurement, flotation kinetics, and induction time measurement. The results of micro-flotation, which respectively feed muscovite or muscovite pretreated with nanobubbles in different concentrations of dodecylamine (DDA), were fitted with four flotation kinetic models using Origin. Different methods were used to examine how the introduction of nanobubbles affected the flotation process. The results showed that nanobubbles improved both the flotation rate and recovery of muscovite. Nanobubbles played different roles in different stirring intensities. At low stirring intensity, nanobubbles did not perform well. In suitable stirring intensity, nanobubbles helped particles aggregate and improved the collision probability between bubbles and minerals. However, at high stirring intensity, shear forces caused by ultra-high fluid velocities could disrupt particle aggregation.

Emulsion properties and plugging performances of active crude oil enhanced by amphiphilic Janus nanosheets

Inadequate strength and stability of active crude oil emulsions stabilized by conventional surfactants always lead to a limited plugging rate of plugging agents. Thus, to address this issue, the synthesis of amphiphilic Janus nanosheets was effectively carried out for enhancing the system performances and subsequently characterized. Based on the outcomes of orthogonal tests, an assessment was conducted on the nanosheet and surfactant formulations to optimize the enhancement of emulsion properties. The experimental demonstration of the complex system has revealed its remarkable emulsifying capability, ability to decrease interfacial tension and improve rheological behavior at high temperature (80 °C) and high salinity (35,000 ppm) conditions. Involving probable mechanism of the system performance enhancement is elucidated by considering the synergistic effect between surfactants and nanosheets. Furthermore, variables including water-to-oil ratio, salinity, temperature and stirring intensity during operation, which affect the properties of prepared emulsions, were investigated in detail. The efficacy and stability of the complex system in obstructing medium and high permeability cores were demonstrated. Notably, the core with a high permeability of 913.58 mD exhibited a plugging rate of 98.55%. This study establishes the foundations of medium and high permeability reservoirs plugging with novel active crude oil plugging agents in severe environments.

Study on the synergistic effect of electromagnetic stirring and mechanical reduction on the improvement of the internal homogeneity of high-carbon steel billet

The synergistic effect of electromagnetic stirring (EMS) and mechanical reduction on the improvement of the internal homogeneity has been studied during the continuous casting of high-carbon steel billet. Plant trials were conducted with different parameters both for mold electromagnetic stirring (M-EMS) and final electromagnetic stirring (F-EMS), at the same casting condition and with a unified mechanical reduction process. As the stirring intensity of EMS increases, both the initiation and termination of columnar to equiaxed transition occur at an earlier timing. The results also indicate that, EMS could result in a decline trend for the compactness of the casting billet to a certain extent, especially in the pure equiaxed crystal zone at the core part of the billet. Under the proper intensity setting of M-EMS and F-EMS, the crack susceptibility of the high-carbon steel billet was markedly decreased by enlarging the mixed crystal zone, which is not arrayed with distinct directionality while featured with a relatively high compactness. The effect of EMS on the solidification behavior, and therefore on the crack susceptibility of the high-carbon steel billet was further explained with the numerical simulation. Consequently, a superior inner quality of high-carbon steel billet was successfully achieved with the effective synergy of EMS and mechanical reduction.

Marine microalgae Schizochytrium demonstrates strong production of essential fatty acids in various cultivation conditions, advancing dietary self-sufficiency

IntroductionPolyunsaturated fatty acids (PUFAs) are essential nutrients that humans obtain from their diet, primarily through fish oil consumption. However, fish oil production is no longer sustainable. An alternative approach is to produce PUFAs through marine microalgae. Despite the potential of algae strains to accumulate high concentrations of PUFAs, including essential fatty acids (EFAs), many aspects of PUFA production by microalgae remain unexplored and their current production outputs are frequently suboptimal.MethodsIn this study, we optimized biomass and selected ω-3 PUFAs production in two strains of algae, Schizochytrium marinum AN-4 and Schizochytrium limacinum CO3H. We examined a broad range of cultivation conditions, including pH, temperature, stirring intensity, nutrient concentrations, and their combinations.ResultsWe found that both strains grew well at low pH levels (4.5), which could reduce bacterial contamination and facilitate the use of industrial waste products as substrate supplements. Intensive stirring was necessary for rapid biomass accumulation but caused cell disruption during lipid accumulation. Docosahexaenoic acid (DHA) yield was independent of cultivation temperature within a range of 28–34°C. We also achieved high cell densities (up to 9 g/L) and stable DHA production (average around 0.1 g/L/d) under diverse conditions and nutrient concentrations, with minimal nutrients required for stable production including standard sea salt, glucose or glycerol, and yeast extract.DiscussionOur findings demonstrate the potential of Schizochytrium strains to boost industrial-scale PUFA production and make it more economically viable. Additionally, these results may pave the way for smaller-scale production of essential fatty acids in a domestic setting. The development of a new minimal culturing medium with reduced ionic strength and antibacterial pH could further enhance the feasibility of this approach.

Effect of the Main Operating Variables on Efficiency of Treating Industrial Flue Gases Using Potash and Yellow Phosphorus

Fossil energy is considered as an important source of energy used in different types of industries. However it emits a great amount of flue gases. Some components of flue gases such as SOx and NOx can cause negative environmental impacts. Acid rains, increasing greenhouse effects and causing humans health problem (for Respiratory system) are some of them. A bench scale experiments using: 2900 ppm SOx, 550 ppmNOx , 1L deionize water, 0.5 g P4, and 10 g MOP were conducted in order to investigate the effects of operating conditions in removing process. These conditions are: emulsion temperature, yellow phosphorus weight, and the emulsion stirring intensity. Optimum conditions for removing process are (55oc, 1743 rpm, using 0.5 g P4). It was also observed that emulsion’s pH and oxygen concentration are declined with reaction time, but they have a positive correlations with removing efficiency, whereas efficiency increasing when rising emulsions temperature and stirring intensity. The obtained results identified the optimum conditions to get the highest efficiency for removing SOx and NOx from flue gases to eliminate their environmental impact

From 7-dehydrocholesterol to vitamin D3: Optimization of UV conversion procedures toward the valorization of fish waste matrices

Vitamin D, a fat-soluble steroid, has increasingly taken a central role due to its crucial role in human health. It is estimated that about 40% of worldwide population are vitamin D deficient. The fish industry produces significant quantities of waste daily, with consequent high environmental impact. The aim of this work is to place a first brick for the fish waste reuse as a source of vitamin D3 extracts to be used for nutraceutical purposes. For this purpose, an UV conversion method for transforming the 7-dehydrocholesterol, highly present in fish, in vitamin D3 has been optimized. The UV wavelength, exposure time, temperature, stirring, and UV intensity were optimized using a surface response design tool. The optimized treatment was applied to five fish species with different fat percentages and the results were very promising reaching vitamin D3 levels >10 times higher than the pre-treatment ones.

OPTIMISATION OF MOGAR GRAIN COOKING METHOD FOR PRODUCTION OF FOOD CONCENTRATE «TALCAN»

The possibility of using mogar grain for the production of food concentrates based on the traditional national dish "Talkan" is considered. "Talkan" is a national food concentrate that has been used for centuries as a staple food for long-distance trekking by representatives of various cultures. Traditionally, talkan is prepared from various cereals, especially millet, wheat and barley. Adding boiling water and butter makes a hearty porridge, and adding butter and sugar makes a delicious dessert.The difficulty lies in the careful handling and preparation of the mogar grain. When cooked intensively, the grain can easily overcook, resulting in all the valuable nutrients being leached into the broth. In addition, improperly prepared mogar can burn during further roasting. To determine the optimal parameters of mogar hydrothermal treatment and to create a high-quality food concentrate based on the national dish "Talkan", a complex experiment was conducted using modern methods of experiment planning.The experiment tested a number of variables including temperature limits and duration of cooking, as well as temperature, duration and intensity of stirring during drying and roasting of mogar. The study showed that the most favourable conditions for mogar grain include cooking at an initial temperature of 15-20 °C for about 60 minutes, gradually reaching 100°C.The established methods of hydrothermal treatment served as a basis for the development of specialised equipment for the preparation of mogar grain to produce tulkan.

Numerical Investigations of Stirring Induced Flow on Solidification and Interface Behavior in Continuous Casting Mold With Bifurcated Nozzle

Abstract Electromagnetic stirring (EMS) is a technique that has the potential to improve steel quality with fine microstructure by fragmentation of dendrites and enhancing the inclusion removal. The success of implementing the EMS lies in the selection of key input parameters such as position, frequency, and current density of the stirrer. In the present study, an integrated mathematical model consisting of liquid steel solidification and two phase interface is numerically developed with the use of EMS. The enthalpy porosity and volume of fluid (VOF) model are adopted for numerical modeling analysis of solidification and interface level fluctuation, respectively. The results reveal that on moving EMS downwards decreases the maximum magnetic field value, widens the mushy zone, and promotes the stability of the interface. Current intensity and frequency are seen to have the opposite effect on stirring intensity and interface fluctuation. With an increase in frequency, both stirring intensity and interface level fluctuations decrease while the high liquid fraction region increases. Moreover, current density enhances the swirling flow intensity and homogenizes the liquid fraction, thereby promoting equiaxed grain formation. Interface fluctuation is seen to increase with current density.

Imiquimod Solubility in Different Solvents: An Interpretative Approach.

Imiquimod (IMQ) has been successfully formulated to date mainly as semi-solid lipophilic formulations for topical application. In this study, we investigated the solubility of IMQ in solvents suitable for developing innovative formulations in the form of powder obtained, for instance, by spray drying; thus, water, ethanol, methanol, acetone, acetonitrile, and dimethyl sulfoxide were tested at different temperatures. Temperature variations, stirring intensity, and the contact time between IMQ and the solvent greatly affected the evaluation of IMQ equilibrium solubility. The attainment of the solid-liquid equilibrium requires 13 days starting from solid IMQ and 2 days from a cooled-down supersaturated IMQ solution. A correlation between IMQ solubility and the solubility parameters of solvents was not found. IMQ solutions in water, ethanol, methanol, acetonitrile, and dimethyl sulfoxide were neither ideal nor regular. The Scatchard-Hildebrand equation does not apply to IMQ solutions because of association phenomena due to intermolecular hydrogen bonds and/or π-stacking, as supported by the hyperchromic effect that was very pronounced in highly polar solvents, such as water, with the increase in temperature. Finally, IMQ solubility values measured in acetone cannot be considered reliable due to the reaction with the solvent, leading to the formation of new molecules.

ИССЛЕДОВАНИЕ ТЕПЛООБМЕНА В АППАРАТАХ С ПЕРЕМЕШИВАЮЩИМ УСТРОЙСТВОМ

This study was carried out with the aim of in-depth analysis of heat transfer processes in chemical and heat apparatuses that use mixing devices. The mixing process plays a key role in various industries, including chemical production, food processing and many others. Mixing is important for uniform distribution of components in reactors, tanks and apparatus, which in turn affects product quality and process efficiency. Heat exchange is a vital element in numerous technological processes and holds a significant role in enhancing efficiency and conserving energy across various industries. This study began with a thorough review of the literature. Further experiments were carried out, including work with different types of apparatuses and stirring devices, with different stirring intensity. Digital prototypes were chosen as the method of research and the ANSYS software package was used. The purpose of this study is to analyze the efficiency of heat transfer in such apparatuses, as well as to identify the factors affecting the intensity of heat transfer. This study addresses following problems: heating water in an apparatus with a stirrer, determining the critical temperature and time to reach steady-state in different mixtures. The study of heat transfer in apparatus with a mixing device is a critical element for optimizing production processes and increasing energy efficiency. According to calculations, faster achievement of the steady-state regime is observed, which indicates more efficient heating of the liquid when using a turbine stirrer. Mathematical calculations confirm that when stirring a mixture of water and glycerin, compared to stirring pure water, a slower and less efficient heating process occurs, due to the higher viscosity of glycerin. This study serves as an important contribution to the field of heat transfer and provides valuable guidelines for further developments and applications.

ABSORBTION KINETICS OF CARBON DIOXIDE BY LITHIUM CARBONATE AQUEOUS SOLUTION

The kinetics of absorption (chemisorption) of carbon dioxide by an aqueous solution of lithium carbonate at a temperature of 293 K and in the pressure range 8.0·103 – 3.2·104 Pa was studied. Lack of inhibition of the reaction by dissolving carbon dioxide, i.e. the occurrence of the reaction in the kinetic region was proven by conducting experiments to establish the dependence of the process rate on the intensity of stirring the solution. The voltage supplied to the stirrer motor was determined, starting from which the kinetic curves of CO2 absorption merged with each other, i.e. the rate of CO2 absorption ceased to depend on the intensity of mixing - the so-called maximum absorption rate. The effect of lithium carbonate concentration on the absorption rate was studied at a constant carbon dioxide pressure of 1.6·104 Pa. It was found that the initial reaction rate was practically independent on the initial concentration (zero order reaction). However, as the reaction product accumulated, it slowed down: the zero order of the reaction passed into the first. The dependence of the reaction rate on carbon dioxide pressure was determined at the same initial concentration of lithium carbonate solution 0.2027 M and different pressures. It was found that with increasing pressure the rate of the process increased linearly. First order on carbon dioxide concentration was observed. To explain the observed patterns, a diagram of the reaction mechanism is proposed, from which the kinetic equation was derived. The effective absorption rate constants were calculated. Based on the proposed reaction mechanism, the inhibition of absorption by the reaction product is explained. Its addition shifts the absorption-chemical equilibrium, thereby reducing the concentration of hydrogen ions. The resulting kinetic equation can serve as the basis for calculating and optimizing the operation of industrial carbon dioxide absorbers.

Preparation of composite coagulant for the removal of microplastics in water.

In this work, a composite flocculant (polyferric titanium sulfate-polydimethyldiallylammonium chloride [PFTS-PDMDAAC]) with a rich spatial network structure was prepared for the treatment of simulated wastewater containing polystyrene (PS) micro-nanoparticles. Characterization results showed that the surface of the PFTS-PDMDAAC was a three-dimensional network polymer of chain molecules that exhibited good thermal stability and formed an amorphous polymer containing multiply hydroxyl-bridged titanium and iron. When n(OH- ):n(Fe) = 1:2, n(PO4 3- ):n(Fe) = 0.35, n(Ti):n(Fe) = 1:8, n(DMDAAC):n(Fe) = 5:100, and the polymerization temperature is 60°C, the prepared composite flocculant has the best effect. The effects of dosage, pH, and agitation intensity on the flocculation properties of PFTS-PDMDAAC were also studied. The optimal removal rates of PS-μm and haze by PFTS-PDMDAAC were 85.60% and 90.10%, respectively, at a stirring intensity of 200 rpm, a pH of 9.0, and a PFTS-PDMDAAC dosage of 20 mg/L. The flocs produced by the PFTS-PDMDAAC flocculation were large and compact in structure, and the flocculation mechanism was mainly based on adsorption bridging. Kaolin played a promoting role in the process of PS-μm removal by PFTS-PDMDAAC floc and accelerated the formation of large and dense flocs. This study provided a reference for the coagulation method to remove micro-nanopollutants in the actual water treatment process. PRACTITIONER POINTS: A composite flocculant with rich spatial network structure (PFTS-PDMDAAC) was prepared. PFTS-PDMDAAC can effectively remove micro-nano polystyrene (PS) in wastewater. The floc produced by PFTS-PDMDAAC is large and compact in structure. The flocculation mechanism of PFTS-PDMDAAC is mainly adsorption bridging.

Vibrations Analysis of Bubble Evolution in Liquids of Varying Physical Properties

In recent years there is an attempt to control the gas stirring intensity in metal-making ladles with the aid of vibration measurements. Understanding better the induced vibrations in two-phase flows can substantially improve the existing models for gas stirring control. In this work, highly sensitive accelerometers were used for the vibration measurements in a liquid metal alloy; Sn–40 wt pctBi alloy at 200 °C and water at 20 °C. The examination of the liquids was conducted in the ladle mockup integrated into the Liquid Metal Model for Steel Casting facility at Helmholtz-Zentrum Dresden Rossendorf. Single bubbles were generated in the respective liquids by controlled argon injection at low flow rates in the range of 0.01 to 0.15 NL min−1 through a single nozzle installed at the bottom of the ladle. Obtained results demonstrate differences between the induced vibrations in the examined liquids in terms of the magnitude of the root mean square values of vibration amplitude and the shape of the resulting curves with increasing flow rate. Furthermore, continuous wavelet transform reveals variations in the duration and vibrational frequency of the evolved bubble phenomena. The findings suggest that differences in the physical properties of the examined liquids result in variations in the vibrations induced during bubble evolution.

Optimization of the method of hydrothermal treatment of mogar grain for production of food concentrate "Talkan"

The possibility of using mogar grain for the production of food concentrates based on the traditional national dish "Talkan" is considered. "Talkan" is a national food concentrate for Republic of Kazakhstan, which has been used as a staple food in long-distance trekking by various cultures for centuries. Traditionally, talkan is prepared from various cereals, particularly millet, wheat and barley. When boiling water and oil are added, it turns into a hearty porridge, and when oil and sugar are added, it becomes a delicious dessert. The difficulty lies in the careful handling and preparation of the mogar grain. During intensive cooking, the grain can easily overcook, resulting in all the valuable nutrients being leached into the broth. In addition, improperly prepared mogar can burn during further roasting. To determine the optimal parameters of mogar hydrothermal treatment and to create a high-quality food concentrate based on the national dish "Talkan", a complex experiment was conducted using modern methods of experiment planning. A number of variables were tested during the experiment, including temperature limits and duration of cooking, as well as temperature, duration and intensity of stirring during drying and roasting of mogar. The study showed that the most favourable conditions for mogar grain involve cooking at an initial temperature of between 15–20 °C for about 60 minutes, gradually reaching 100 °C. The drying and roasting processes are best carried out for 25 minutes, with a layer thickness of 25 mm and a surface temperature of 250 °C. The determined of hydrothermal treatment serve as a basis for the design of specialised equipment for preparation of mogar grain for the purpose of making Talkan

Monitoring effects of hydrodynamic cavitation pretreatment of sodium oleate on the aggregation of fine diaspore particles through small-angle laser scattering

Hydrodynamic cavitation (HC) enhanced fine particle aggregation could be largely due to the generation of tiny bubbles and their role in bridging particles. However, the lack of adequate characterizations of aggregates severally limits our further understanding of the associated aggregation behaviors. In this study, the aggregation of fine diaspore particles was comparatively investigated in sodium oleate (NaOl) solutions with and without HC pretreatment through the small-angle laser scattering (SALS) technique in a shear-induced aggregation (SIA) system. Results showed that HC pretreatment caused the formation of bulk nanobubbles (BNBs), which significantly modified the particle interactions and thereby modified the size and mass fractal dimension (Df) of aggregates under different SIA conditions. Although HC pretreatment did not noticeably alter the gradual change trend of aggregate size and structure characteristics under specific variables, BNBs bridging facilitated the aggregation process towards the diffusion-limited cluster aggregation model, resulting in the formation of larger but looser aggregates. This effect was more pronounced under relatively high NaOl concentrations. Apart from BNBs, the aggregation was also affected by cavitation bubbles formed during shear cavitation, which was more significant under high stirring intensity conditions (i.e., 1800 rpm) than the low stirring intensity conditions (i.e., 600 rpm).

Dielectric barrier discharge plasma-modified chitosan flocculant and its flocculation performance

The flocculation performance of chitosan can be enhanced by grafting modification to overcome its disadvantages of poor water solubility. In this study, chitosan was modified by dielectric barrier discharge plasma and polymerized with acrylamide and aluminum chloride to synthesize a new chitosan-based flocculant, namely, chitosan–acrylamide–aluminum chloride (CA-PAC). After optimizing the synthesis conditions of CA-PAC, the best conditions were as follows: discharge time of 3 min, discharge power of 50 W, polymerization temperature of 60 °C, polymerization time of 3 h, total monomer concentration of 100 g/L, and m(AlCl3):m(CA) ratio of 2:1. Characterization was performed through SEM, XPS, FTIR, XRD, TG and 1H NMR. Results showed that the preparation of CA-PAC was successful. The influences of flocculant dosage, pH, and stirring intensity on flocculation efficiency were investigated. The removal efficiency of turbidity was 94.1 %. The investigation of the flocculation mechanism revealed that CA-PAC mainly relied on charge neutralization or the synergic action of electric neutralization, bridging, and roll–sweep under acidic and neutral conditions, but it depended on the joint action of adsorption bridging and net sweeping under alkaline conditions. This study provides new ideas for the preparation and development of modified chitosan and broadens its application in water treatment.

Establishment and Verification of the Kinetics Model of Uranium Continuous Dissolution by Using Discrete Element Method

Continuous dissolution of spent fuel is indeed one of the key technologies that can significantly improve the efficiency and stability of spent fuel reprocessing. The China Institute of Atomic Energy designed a prototype rotary drum dissolver, and the dissolution behavior of UO2 pellets in the dissolver was calculated using the Discrete Element Method. A kinetic equation was established to model the dissolution behavior, considering variables such as temperature, nitric acid concentration, and stirring intensity. The calculations showed that complete pellet dissolution took about 10 h in the continuous reaction, compared to 6 h in the batch dissolution experiment due to the gradual decrease in nitric acid concentration. A 16 h continuous dissolution experiment confirmed the calculated results, with a deviation of 10.8% between the simulation and experiment in terms of the mass of dissolved pellets. It was also found that it takes approximately 30 h to reach equilibrium in the continuous rotary dissolver, with a nitric acid concentration of 2.8 mol/L and a uranium concentration of 243 g/L at equilibrium.

Suspension oligomerization of C9 hydrocarbon fraction initiated by aliphatic N-substituted aminoperoxides

We investigated the production of petroleum resins by suspension oligomerization of С9 hydrocarbon fraction initiated by aliphatic aminoperoxides. The reaction mixture consisted of a dispersion medium (water), a dispersed phase (C9 fraction), an initiator, which is soluble in the dispersed phase, and a suspension stabilizer. In the range of variables studied, reaction temperature (313–353 K) and initiator concentration (0.032–0.096 mol/l) do not have a significant effect on the oligomers yield. The process conditions most influencing the course of suspension oligomerization of the С9 fraction are as follows: stirring intensity (Re=2290–13450) with the correlation index of 0.88, reaction time (30–240 min) with the correlation index of 0.87 and the ratio of dispersed phase to dispersed medium (1:1–1:4) with the correlation index of –0.91. The correlation between the yield and bromine number (correlation index of –0.82) confirmed the passage of oligomerization reaction via the unsaturated bonds of the monomer. The hydrocarbon resins obtained by low-temperature suspension oligomerization were mainly cooligomers of styrene and its derivatives. As a result of suspension oligomerization at low temperatures, products were obtained which were characterized by a light color (color index of 10–20 mg I2/100 ml), a molecular weight of 505–530 and a softening point of 347–354 K.