Titanium Production Research Articles

Structure, properties, production and photocatalytic processes of titanium (IV) oxide

Structure, properties, production and photocatalytic processes of titanium (IV) oxide

The size and temperature effect on titanium Ti7 cluster in β-TiCl3 medium

In the Kroll process, the reduction process results in the production of intermediates such as titanium trichloride (TiCl3) and titanium dichloride (TiCl2). There has been experimental work on developing a continuous reduction process using TiCl3 and TiCl2. However, more investigations still need to be done to understand these mediums and their interactions. In this paper, we will be investigating one TiCl3 polymorph as a potential medium for titanium production. We employ the DL_POLY code to understand the effect of temperature on the Ti7 cluster using a stable β-TiCl3 medium. It was observed from the total energies that the system is stable at 50 – 700 K. The diffusion coefficient results showed that the Ti7 nanocluster diffuses faster than Ti and Cl at 1300 – 2000 K.

Ba2+ ions adsorption by titanium silicate

This paper is devoted to the adsorption capacity of titanium silicate toward Ba2+ cations. Titanium silicate can be synthesized from titanium production waste by sol-gel synthesis, which is of additional benefit to environmental protection. The determination of the surface area of the adsorbent was performed by the method of low-temperature N2 adsorption-desorption isotherm. The elemental composition of titanium silicate was also investigated by XRF and EDS analysis. The dependence of the adsorption values of Ba2+ on the duration of interaction, the equilibrium concentration of adsorbate, and the acidity of the solution has been investigated. The adsorption theories of Langmuir, Freundlich, and Dubinin-Radushkevich were applied to the equilibrium adsorption of barium ions. The experimentally measured maximal adsorption value of Ba2+ ions is 144 mg/g. Barium is adsorbed onto titanium silicate by the mechanism of physical adsorption, this is indicated by the value of the adsorption energy equal to 0.947 kJ per mole, which was calculated using the D-R equation. This may be useful for researching the possibility of adsorbent regeneration.

A novel low‐energy approach to leucoxene concentrate desiliconization by ammonium bifluoride solutions

AbstractBACKGROUNDDespite the large reserves of titanium ores, their treatment by basic approaches to obtain titanium products is not always economically feasible due to various factors. One of these problems is the high content of silicon in the ores.RESULTSThe paper considers the desiliconization of a leucoxene concentrate with an aqueous solution of ammonium bifluoride. It was found that at 80 °C the main impurities, such as silicon and iron, pass into solution in the form of corresponding ammonium–fluorine complex compounds.CONCLUSIONSThe degree of desiliconization was up to 99%. Aluminium reacts with ammonium bifluoride, but is almost not leached into solution due to its low solubility. Titanium does not react due to its relatively higher reaction Gibbs energy among other metals in reaction with ammonium bifluoride. The content of titanium oxide in the calcined leaching residue was 85.52 wt%. The resulting residue corresponds to the raw material used in industry for the production of titanium dioxide pigment or titanium metal by the chlorine method. Iron and silicon can be precipitated from the leaching solution. Furthermore, the resulting filtrate can be evaporated in order to regenerate and reuse ammonium bifluoride. © 2022 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).

Determining the thermoplastic deformation mechanism of titanium reduction reactors and recommendations to increase the reactor service life

The object of research reported in this paper is the stressed-strained state of reactors when producing titanium sponge by the magnesium thermal method, taking into consideration the conditions of their operation and the physical and mechanical properties of the materials. The problem considered is the plastic deformation of the reactor in the process of reducing titanium tetrachloride. To solve this task, an axisymmetric geometric model of the reactor was built using a CAD module of the Comsol Multiphysics software package. For the calculation, the Nonlinear Structural Materials module was used. Owing to the method of finite elements, the critical parameters for the formation of the plastic deformation band of the reactor were determined. Modeling the process of thermoplastic deformation of the reactor under the conditions of obtaining titanium sponge has made it possible to determine the temperature gradient in the upper part of the reactor wall, which leads to local plastic deformation of the wall. The solution to the problem of continuing the reactor service would be to prevent overheating (overcooling) of the reactor wall within the resulting temperature. The physical and mechanical parameters of the material of the reactor wall, necessary to prevent the occurrence of an annular band of plastic deformation, have also been determined. It was shown that at ∆T˃∆Tcrit=60 °C, the walls of a 10-ton reactor during the reduction of titanium tetrachloride with magnesium perceive plastic deformation whose maximum value can reach Deformation mechanisms that lead to a change in the shape of the side wall of reactors of magnesium-thermal production of sponge titanium under the action of a heterogeneous temperature field have been determined. The proposed technological solutions are to eliminate local changes in diameter in the upper part of the reactor wall. This will make it possible not only to increase the life of the reactors but will reduce the flow of alloy components into the titanium sponge of nickel, chromium, and iron

Impact of the industrial environment on the health of workers in titanium and magnesium production

The results of a study of the health status of employees of metallurgical enterprises under the conditions of exposure to rare earth elements (on the example of employees of titanium and magnesium production) are presented. 107 workers (men) of the observation group exposed to harmful production factors and 72 employees of the administrative apparatus without exposure to harmful production factors were examined. An analysis of the working conditions of workers, research on the content of rare earth elements in the air of the working area and in bioassays, and a sociological survey were carried out. The general clinical, biochemical, immunological parameters of the blood of workers in the titaniummagnesium production were studied. A functional study of the cardiovascular, respiratory, digestive, and nervous systems was performed. According to the results obtained, the final class of working conditions at the workplace corresponded to classes 3.1–3.3. Exceeding the MPC of rare earth elements and estimated safe exposure levels have not been identified. An increase in the content of europium, which can replace calcium and magnesium in the body, was found in the workers of the observation group. The revealed dysfunction of the autonomic nervous system and impaired adaptation of the body are formed as a result of exposure of workers in the titanium-magnesium production to a harmful production environment. Exposure of chemicals in workers causes a change in humoral immunity in the form of hyperproduction of IgA, and with an experience of more than 5 years, activation of cellular immunity (increased absolute phagocytosis, CD16+56+ and CD3+25+). Recorded changes in the parameters of rhinomanometry and spirography in the observation group may indicate the presence of the process of aseptic inflammation in the airways under the combined effect of irritating chemicals and rare earth elements. Low-symptomatic or asymptomatic liver damage, characterized by non-specific structural changes (hepatomegaly, increased echogenicity) and a laboratory symptom complex of a simultaneous increase in AlAt and AsAt, LDH. The emerging dysfunction of the cardiovascular and respiratory systems is transformed into cardiorespiratory and hepatopulmonary pathology, increasing the risk of sudden death. The combined impact of production factors «rejuvenates» the age of formation of production-related and occupational diseases, contributes to the loss of professional working capacity by employees even before retirement age.

Effect of fibre laser welding parameters on the microstructure and weld geometry of commercially pure titanium

The primary purpose of the study was the metallurgical characterization of laser welds. The weldability of commercial production of pure titanium and titanium alloy (CP-Ti) has also been examined. In this research, the laser fibre method was used to weld sheets of pure titanium, and then microscopy and scanning electron microscopy were used to study the changes in the microstructure, the depth of weld penetration and the width of the weld area with changing welding parameters. The results proved that increasing the laser power significantly increases the depth of weld penetration and weld width. When the heat input is increased, the shape of the weld pool changes from a V shape to an hourglass shape. It was also observed that the depth of the crater formed increases with the increase in the laser power due to the increase in the melting and evaporation of the weld metal. Increasing the welding speed also has a negative impact on the weld geometry because it reduces the heat input and absorption of laser energy by the weld metal and thus reduces the melting of the metal. The microstructure of the fusion zone consists of acicular α. Fine grains formed in the weld centre at low heat input; the granules became columnar-like. Since commercially pure titanium contains a small amount of beta-phase stabilizers, the cooling rate is extremely high for martensite to occur. In the future, it is recommended to study the effect of changing welding parameters on the mechanical properties of pure titanium because of its great importance in industrial and medical applications. Studying the effect of changing laser power and welding speed on the metallurgical properties of pure titanium, and consequently its effect on the mechanical properties of welds.

Investigation of MAO Coatings Characteristics on Titanium Products Obtained by EBM Method Using Additive Manufacturing.

Coatings with a thickness from 27 to 62 µm on electron beam melted Ti-6Al-4V have been formed by micro-arc oxidation (MAO) in a silicate-hypophosphite electrolyte. MAO tests in the anode-cathode mode (50 Hz) with an anode-to-cathode current ratio of 1:1 and sum current densities 10 and 20 A/dm2 were carried out. The duration of the MAO treatment was 30 and 60 min. The effect of the processing parameters on the structural properties of the MAO treated coatings was studied. The current density and treatment time significantly affect the coating thickness and surface roughness. The values of these characteristics increase as the current density increases. The effect of thermal cycling tests on surface morphology, thickness and roughness, and elemental and phase composition of MAO coatings was analyzed. After 50 cycles of thermal cycling from +200 °C to −50 °C, no cracking or delamination of coatings was observed. Coatings formed in 30 min at a current density of 20 A/dm2 turned out to be the best in terms of such indicators as surface morphology, thickness, and roughness.

Minimizing pest aluminum in magnesium for the production of high-purity titanium

It is practically difficult to find titanium sponges with low and stable aluminum impurities on the market even though it is the precondition to prepare high-purity titanium. Analysis indicates that almost all the aluminum impurities in the titanium sponge are inherited from the magnesium used to reduce titanium tetrachloride. However, it remains elusive for decades why magnesium produced through the silicothermic reduction method contains a high content of aluminum impurities with large fluctuations. By recourse to thermodynamic calculations and comparative experiments, we demonstrate that fluorite, a material used as a catalyst in the silicothermic reduction method to produce magnesium, is the chief culprit for the pest aluminum and propose a mechanism to rationalize the observed phenomena. Our findings indicate that one practical way to produce qualified magnesium for the production of high-purity titanium is to abandon fluorite during the production of magnesium with the silicothermic reduction method.

Production and characterization of titanium based metal matrix composites: a review

Titanium alloys are regarded as high strength and lowdensity alloys. It has wide range of applications such as in biomedical and automobile because of its high strength, low density, biocompatibility and good corrosion resistance. Titanium alloys can be produced by adding elements like aluminium, vanadium, molybdenum, zirconium etc. The powder metallurgy method is widely used method for production of titanium alloys because of its low cost of production. In this study, Ti6Al4V based composites synthesized by adding various reinforcements through powder metallurgy method are considered and the results from these studies are reported.

TITANIUM IN JEWELLERY AND COSTUME JEWELLERY

The article deals with the peculiarities of the use of titanium in jewellery and costume jewellery. It is shown, under what conditions products, where titanium is used, are jewellery, and under what conditions, costume jewellery. Advantages and disadvantages of titanium jewellery and peculiarities of its design, production and operation are considered. It is shown that for several years leading jewellery brands have been successfully using titanium for production of advanced collections. Some examples are given. Contemporary Russian jewellers also keep up with the leading jewellery brands, demonstrating pieces made of titanium of advanced design. It is shown that though fashion for titanium products is not widespread, but unique items of titanium jewellery are more often gaining their admirers.

Fluoroammonium method for processing of cake from leaching of titanium-magnesium production sludge

We present the results of the physical and chemical properties of cake from nitric-acid leaching of titanium production sludge. It was found that all silicon in the cake is in the form of quartz, albite, sillimanite, sodium aluminosilicate. In total, these minerals make up the majority of the cake 60.24%. Titanium is presented in the form of rutile, titanium aluminum oxide, which in total is 35.56%. Iron is part of sillimanite and hematite, the total content of which is about 4.2%. The optimal parameters of fluoroammonium processing of cake were determined: silicon distillation into sublimates at 300°С for 6 hours, sublimation of titanium in the form of titanium tetrafluoride at 800°С for 2 hours. The process of alkaline hydrolysis of sublimates of fluoride compounds and cinder was carried out. Purification of impurities and calcination of hydrated titanium dioxide were carried out. The resulting titanium and silicon dioxide products contain: 96.2% TiO2, 88 % SiО2, respectively; a niobium-containing intermediate product with a content of 11.6 % Nb2O5 was also obtained.

Analysis of the effect of toxic chemicals on the physiological parameters of experimental animals

Titanium and its alloys are widely used in modern supersonic aircraft and rockets, submarines and ships, in the chemical and food industries, as well as in other areas of modern technology. In the process of obtaining titanium from ore, workers may be exposed to titanium metal dust (Ti) and titanium dioxide (TiO2), highly toxic chemical compounds – gaseous titanium tetrachloride (TiC14), its hydrolysis products, chlorine and phosgene vapors. The study of the influence of titanium produc-tion conditions on the body was carried out at the Ust-Kamenogorsk Titanium and Magnesium Plant (JSC UKTMP) of Kazakhstan, one of the largest enterprises for the production of titanium. To study the behavioral reactions of rodents under the influence of harmful components of the production of magnesium, titanium and their compounds, the «Open field» test was carried out. This test refers to methods that study conditionally unconditioned reflexes. Sexually mature white rats of the Wister line, weighing 180-220 g, were used as a model object; experimental animals were placed on the territory of three main workshops. The motor and emotional behaviors of experimental animals were studied. The assessment of motor activity indicators was determined using such indicators as locomotion and standing, and emotional activity was determined by the number of grooming and boluses (urination and defecation). As a result of the experiment, a unidirectional change in physiological parameters was revealed in animals that were on the territory of JSC «UK TMP» shops, and the quantitative characteristics of physiological processes were different – more pronounced in shop No. 1 (Shop «Magnesium») and less – in shop No. 3 (Shop «Titanium Sponge»).Key words: titanium-magnesium production; experimental animals, physical activity, emotional ac-tivity.

A novel moldless porous titanium formulae for dental post system: Part 1 – Development and characterization

Titanium production using mold sintering is a time-consuming and costly technique. This study aimed to develop a formula for moldless porous titanium that can be used for dental post systems in dentistry. Three different percentages of titanium powder (size ≤ 150 µm) were selected as follows: 85 wt% titanium powder (G1), 90 wt% titanium powder (G2), and 95 wt% titanium powder (G3). The titanium powder was mixed with a wax binder and then subjected to furnace heating in two heating environments (air and argon). A total of 36 samples were prepared for testing the compressive and flexural strengths. A scanning electron microscope (SEM) was used to investigate the morphology of the samples. The results were presented as means and standard deviations in Mega Pascal. Differences between the mixtures were explored using the Kruskal-Wallis test (α < 0.05). The compression test revealed a higher value for G1 compared with other groups (17.66 ± 3.06 MPa for G1, 14.78 ± 3.40 MPa for G2, and 17.49 ± 3.08 MPa for G3), with no significant difference (P = 0.241). Similarly, the flexural test showed a higher value for G1 compared with other groups (5.76 ± 4.04 MPa for G1, 2.18 ± 0.38 MPa for G2, and 5.18 ± 1.14 MPa for G3), with a significant difference (P = 0.004). The SEM showed a porous surface with a good melting appearance of the particles outside and inside the samples. A 85% titanium powder and 15% wax binder can be used as a promising mixture for moldless use in developing porous titanium dental posts.

СУЧАСНИЙ СТАН МІНЕРАЛЬНО-СИРОВИННОЇ БАЗИ РОЗСИПНИХ РОДОВИЩ ТИТАНУ УКРАЇНИ

The current state of titanium deposits in the world and Ukraine's place in the world of titanium ore reserves are analyzed. The list of leading countries in terms of reserves of loose titanium-zirconium ores and the dynamics of production is given. There is no regularity of the ratio of countries in terms of reserves and countries in terms of production. A map of the countries to which Ukraine exports titanium raw materials and the dynamics of titanium dioxide prices over the past 5 years are presented. The list of available mining enterprises for enrichment and production of titanium products within Ukraine is given. The general characteristic of the mineral resource base of titanium of Ukraine with the map of the current state of ilmenite and complex zircon-ilmenite placers of the Ukrainian Placer Province is provided.

The stability of three phases of TiCl3: a molecular dynamics approach

Titanium is produced commercially by the Kroll process, which involves the magnesiothermic reduction of titanium tetrachloride (TiCl4). However, this is not suitable for developing a continuous reduction process. Recently, there have been attempts to develop a new continuous titanium production process by magnesiothermic reduction of other subchlorides such as titanium trichloride. In this study, the DL_POLY code was employed to investigate the influence of temperature on TiCl3 (α, β, γ). We found that the γ-phase is ordered, and all phases are spontaneous at 50 – 2000 K. The order of stability is β &gt; α &gt; γ, in agreement with other reported work. These findings suggest that TiCl3 might be used as a potential medium in the titanium production process.

Features of modeling a polymer implant for closing a defect after decompressive craniotomy

Individual polymer implants are widespread for bone reconstruction after decompressive craniectomy. Despite the availability of customized titanium products, various specialists and hospitals prefer polymer implants. To compare the methods of modeling and manufacturing the polymethylmethacrylate implants and identify the features affecting the quality of reconstruction. We analyzed 14 patients with extensive skull defects after installation of polymethyl methacrylate implants. Software used for modeling of individual implants by different specialists was compared. Satisfactory reconstruction result was obtained in all cases. There were no infectious complications. The authors outlined certain important aspects for modeling of individual polymer products: local use of anatomical thickness of the implant, leaving safe spaces, prevention of temporal retraction, template-based resection before reconstruction. To date, skull defect closure with polymeric materials remains relevant, and even has certain advantages over customized titanium products.

The Current Progress of the Titanium Preparation by Electrolysis in the Room-Temperature Ionic Liquid Electrolytes

Titanium is a beneficial metallic material due to its excellent properties. However, the large-scale application of titanium is inhibited by the high production cost of the Kroll process. To address this challenge, researchers have proposed many new strategies based on electrochemical technology over the past decades. Those electrochemical methods show potential practical value to replace the Kroll process. Nevertheless, many of them are conducted in high-temperature melts, limiting the rapid development of those methods. Accordingly, room-temperature electrolysis in ionic liquid electrolytes was employed in titanium production. At present, there is no systematic and in-depth summary on room-temperature titanium electrolysis, although many pathways in room-temperature melts have been reported. In this review, we briefly outline the development of the titanium electrolysis methods firstly and summarize the room-temperature titanium electrolysis in ionic liquid electrolytes. Furthermore, we have discussed the fundamental mechanisms and key challenges occurring in room-temperature titanium electrolysis. Finally, we proposed the opportunities and research direction on room-temperature titanium electrolysis. We hope this review will be a valuable roadmap for room-temperature titanium electrolysis.

Titanium: An Overview of Resources and Production Methods

For several decades, the metallurgical industry and the research community worldwide have been challenged to develop energy-efficient and low-cost titanium production processes. The expensive and energy-consuming Kroll process produces titanium metal commercially, which is highly matured and optimized. Titanium’s strong affinity for oxygen implies that conventional Ti metal production processes are energy-intensive. Over the past several decades, research and development have been focusing on new processes to replace the Kroll process. Two fundamental groups are categorized for these methods: thermochemical and electrochemical. This literature review gives an insight into the titanium industry, including the titanium resources and processes of production. It focuses on ilmenite as a major source of titanium and some effective methods for producing titanium through extractive metallurgy processes and presents a critical view of the opportunities and challenges.

Induction-thermal action effect on the surface area of titanium products

The changes in the surface area of titanium samples occurring during induction heat treatment (IHT) were studied. The dependence of the surface area of titanium samples on the exposure temperature was revealed. When a titanium sample was heated to a temperature of 1000 °C in the air at an exposure time of 60 s, there was a 45-fold area increase. The assessment of the porosity of the formed coating is carried out. The number of pores increased with increasing temperature from 374 to 1029 pieces. Accordingly, the average pore size decreased by 40%.