• Bulletin of the Korean Chemical Society
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• v.9 no.1
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• pp.15-17
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• 1988

Titanium tetrachloride is purified using adsorption column packed with activated silica gel. When 120 ml of titanium tetrachloride was passed through an adsorption column filled with 7 g silica gel, iron content in titanium tetrachloride has been reduced from 7 ppm to less than 1 ppm, and aluminum from 46 ppm to 11 ppm, while silicon content being unchanged at about 60 ppm.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.4
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• pp.166-169
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• 2018

$TiO_2$ nanoparticles were prepared under high temperature and pressure conditions by precipitation from titanium tetrachloride ($TiCl_4$) and titanium isopropoxide (TTIP). $TiO_2$ powders were obtained in the temperature range of $150^{\circ}C{\sim}190^{\circ}C$ for 4 h. The microstructure and phase of the synthesized particles were studied by TEM and XRD. TEM and X-ray diffraction pattern shows that the synthesized particles were crystalline. The average sizes of the synthesized particles from titanium tetrachloride and titanium isopropoxide were below 20 nm and 10 nm, respectively. The average size of the synthesized particles increased with increasing reaction temperature. The effects of synthesis parameters, such as the reaction temperature and pH value are discussed.

• Journal of the Korean Chemical Society
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• v.18 no.6
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• pp.408-414
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• 1974

The direct reactions of titanium tetrachloride with piperidine and diphenylamine in dichloromethane have been studied by examining the isolated reaction products. In the reaction with piperidine, titanium tetrachloride undergoes both addition and substitution reactions as in the following: $TiCl_4+C_5H_{10}NH{\to}TiCl_4{\cdot}C_5H_{10}NH$$TiCl_4+C_5H_{10}{\to}TiCl_3{\cdot}NC_5H_{10}+HCl$ The addition reaction is relatively fast and completed in minutes whereas the substitution reaction is very slow. The both reaction products coprecipitated with piperidine hydrochloride formed during the substitution reaction were isolated and characterized. The reaction with diphenylamine resembles to the above reaction but the addition compound could be obtained in pure crystal form.

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.263-264
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• 2003

• Korean Journal of Metals and Materials
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• v.50 no.10
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• pp.745-751
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• 2012

The Kroll process for magnesium reduction of titanium tetrachloride is used for mass production of titanium sponge. The present study was conducted in a lab scale reactor to develop a better understanding of the mechanism of titanium sponge formation in the Kroll reactor with respect to reaction degrees and the feeding rate of $TiCl_4$. The $MgCl_2$ produced during the initial stage of the reaction was not sunk into the molten magnesium, but covered the surface of the molten magnesium. As a result, subsequently fed $TiCl_4$ reacted with Mg exposed on the edge of molten $MgCl_2$ in the crucible. Therefore, titanium sponge grew toward the center of the crucible from the edge. The temperature of the molten magnesium increased remarkably with the increasing feeding rate of $TiCl_4$. Consequently, fed $TiCl_4$ reacted at the upper side of the crucible with evaporated Mg, and produced titanium on the upper surface of the crucible wall, which increased considerably with the feeding rate of $TiCl_4$.

• Korean Journal of Materials Research
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• v.4 no.5
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• pp.541-549
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• 1994

The crystallization behavior and structural change of amorphous $PbTiO_{3}$ precursors prepared by coprecipitation method were investigated by XRD, Raman spectra, TEM, and RDF. The precursors were prepared at $45^{\circ}C$ and pH of 9 from a mixed solution of lead nitrate and titanium tetrachloride derived using $H_2O_2$ or $NH_4NO_3$ as an ion stabilizer. The activation energy and temperature for crystallization of the coprecipitate prepared using $NH_4NO_3$ as an ion stabilizer were lower than that derived from the solution containing $H_2O_2$ stabilizer. The amorphous coprecipitate transformed to transient phase and then to crystalline $PbTiO_{3}$. Average interatomic distances of amorphous states decreased with increasing heat-treatment temperature.

• Journal of Korean Society on Water Environment
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• v.31 no.6
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• pp.619-624
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• 2015

This study experimentally determined the effect of titanium tetrachloride (TiCl₄) concentration ([TiCl₄]) (0.25-0.55 mM) and initial pH (3-11) on phosphorus (P) removal in synthetic wastewater (2 mg P/L). The P removal efficiency increased when [TiCl₄] increased. The P removal efficiency showed a parabolic trend with an inflection point at pH 7. At the molar ratio of TiCl₄ and P>6.2, the P removal efficiency was over 90% and the residual P concentration was less than 0.2 mg/L. Within the design boundaries, the complete P removal could be achieved at 7.0≤initial pH≤8.5 and 0.43≤[TiCl₄]≤0.55 mM. The final pH was over 5.8 at initial pH≥7.7 and [TiCl₄]≥0.35 mM. The results showed that TiCl4 was effective in P removal in water so that it could be an alternative chemical for P removal.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.115-115
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• 2011

Nano hybrid superlattices consisting of organic and inorganic components have great potential for creation of new types of functional material by utilizing the wide variety of properties which differ from their constituents. They provide the opportunity for developing new materials with new useful properties. Herein, we fabricated new type of organic-inorganic nano hybrid superlattice thin films by a sequential, self-limiting surface chemistry process known as molecular layer depostion (MLD) combined with atomic layer deposition (ALD). An organic layer was formed at $150^{\circ}C$ using MLD with repeated sequintial adsorption of Hydroquinone and Titanium tetrachloride. A $TiO_2$ inorganic nanolayer was deposited at the same temperature using ALD with alternating surface-saturating reactions of Titanium tetrachloride and water. Using UV-Vis spectroscopy, we confirmed visible light absorption by LMCT. And FTIR spectroscopy and XPS were employed to determine the chemical composition. Ellipsometry and TEM analysis were also used to confirm linear growth of the film versus number of MLD cycles at all same temperature. In addition, p-n junction diodes domonstrated in this study suggest that the film can be suitable for n-type semiconductors.

• Resources Recycling
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• v.32 no.2
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• pp.19-32
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• 2023

A novel method for the synthesis of titanium hydride powder from titanium tetrachloride via the magnesiothermic reduction in an hydrogen gas atmosphere was investigated. To examine the influence of temperature on the formation of titanium hydride, the reduction was conducted at 1023~1123 K under 1 atm of hydrogen gas atmosphere for approximately 30 min. Subsequently, the titanium hydride powder was sintered by maintaining the temperature for 0~120 min, and the decrease in the oxygen concentration of the powder was investigated. The experimental results showed that TiH_1.924 was produced at 1023 K, whereas mixtures of TiH_1.924 and TiH_1.5 were produced at 1073 K and 1123 K. In addition, the hydrogen concentration in the powder decreased with increasing temperature. The concentration of oxygen in the powder decreased with increasing temperature and sintering time owing to the decrease in the specific surface area of the powder. The minimum concentration of oxygen was 0.246 mass% when the mixture of TiH_1.924 and TiH_1.5 was obtained at 1073 K and a sintering time of 120 min.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.15-17
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• 1957

1. Preparation of Titanium tetrachloride; The following precesses were strictly followed as the preliminary step to obtain pure $TiOCl_2$, titanyl chloride; First, pure Titanium Oxide mixed with carbon is rolled into pills. After drying up perfectly, these pills are heated at 900∼1000${\circ}C$. And then the pills are subjected to the flow of $Cl_2$ gas in a quartz tube heated to 900-1000${\circ}C$. Thus Titanium tetrachloride is obtained. 2. Preparation of $TiOCl_2$ ; Yellowish trobrown solution is made by pouring 80 g of conc. HCl (sp.gr. 1.19) to 45 gr of Titanium tetrachloride (approx. 2 times of theoretical amount). Then this solution is kept settled for 5-days in a desiccator filled with phosphorous pentoxide at room temperature. As the colorless amorphous solid thus obtained is washed with aceton, 36.5 g of the pure salt are obtained. 3. Determination of composition. The analysis of the sample taken from the deposit desiccated gives the following data; (A) Qualitative analysis; a) $Ti(OH)_4$ is precipitated by adding NaOH in water solution of the salt. b) Adding $AgNO_3$ solution, the water solution of the salt gives white precipitate of AgCl. c) When acid and $H_2O_2$ are added, the solution turns its color to redish brown (This proves that $TiO^{++}$ was converted into $TiO^{++}$ by oxidation of $H_2O_2$. (B) Quantitative analysis; a) $Ti(OH)_4$ precipitated by $10{\%}$ NaOH isalitatsubjected consecutively to the filtration and ignition in porcelain crucible at approx. 1000${\circ}C$. , then $TiO_2$ thus formed is weighed and calculated into Ti content. b) Chlorine involved in water solution of the salt is determined by Vorhardt method. Result: The values obtained from previous analysis, devied by their atomic weight gives the following composition: Ti : Cl = 1 : 2 Therefore $TiOCl_2$ should be given as its molecular formula. 4. Summary. When $TiCl_4$ is additated into conc. HCl, $TiO^{++}$ formed exists as a stable form, and forms $TiOCl_2$. However $TiOCl_2$ is unstable to heating. When the temperature is raised to $65{\circ}C$the decomposition of the solution is accelerated, and gives $TiO_2$ aq. $TiOCl_2$ in addition is highly hygroscopic.