Assessment of Titanium Carbide Chlorination by Statistical Design

Abstract

In present study, the effects of the process parameters on chlorination of Titanium Carbide (TiC) was studied. Besides that, process parameters were investigated by using experimental design of experiment (DOE) and statistical analysis. The chlorination of the samples was carried out at temperatures between 400 to 500°C. Effects of three parameters, namely temperature, soaking time, and molar ratio of potassium permanganate (KMnO4) to hydrochloric acid (HCl) were investigated. The interaction, on the rate of chlorination of TiC were statistically evaluated by using DOE. The weight loss (wt. %) was the main response taken into account in this paper. The results of the experimental design indicated that the main significant factor for chlorination of TiC was higher temperature, soaking time and higher molar ratio of KMnO4 to HCl. DOE results have demonstrated that the highest extent of chlorination obtained at the highest weight loss (wt. %) was about 54.59 wt. % at 500°C with a soaking time of 180 minutes and KMnO4 to HCl molar ratio of 0.17 respectively. The amounted to a titanium extraction of about 96.39 %. On the other hand, the lowest wt. lost was 30.76 wt. % and this was obtained at 500°C for 120 minutes with KMnO4 to HCl molar ratio of 0.09 respectively. The results obtained from this work will be employed as a guide for the future studies on chlorination of nitrided/carburized Malaysian ilmenite or titanium oxycarbonitride. The final aim was to produce TiCl4 at low temperatures (≤500°C) using the latter samples. The experimental values are in good agreement with calculations from the statistical model.

Extraction of titanium from low-iron nitrided Malaysian ilmenite by chlorination

“…The data obtained in this study has validated the previous findings by Venable and Jackson in 1920 18 that showed when excess acid was used in the reaction between KMnO4 and HCl, manganese dioxide (MnO2) was formed instead of producing chlorine gas. On the other hand, at higher KMnO4 : HCl molar ratio, studies by Ahmadi, E. et al 2 Figure 2 shows the XRD patterns for nitrided Malaysian ilmenite and the residues resulted after the chlorination process of the samples at different conditions. It can be shown that, TiN (ICSD# 98-000-5755) main peak at (002) plane decreased as the molar ratio of KMnO4: HCl and soaking time increased.…”

“…The pellets were then chlorinated in a tube furnace under flowing N2 gas as a carrier gas (20 cc/min) at 500ºC for 30, 45 and 60 minutes. The details for the chlorination experiments have been publicationed elsewhere 2,8 . Aluminum powder was used as a catalyst to speed up the reaction between hydrochloric acid and potassium permanganate to generate significant amounts of chlorine gas.…”

“…In the low-temperature chlorination process, impurities do not react with chlorine gas to any significant extent or may become chlorinated at very slow rate 8 . Thus selective chlorination of titanium oxycarbonitride not only decreases the chlorine gas usage but also reduces the waste generation, and makes the present route more feasible and sustainable 1,2,7 . TiOxCyNz can be produced from the carbothermal reduction and nitridation (CTRN) of ilmenite (FeTiO3) 2,4,9 .…”

“…Thus selective chlorination of titanium oxycarbonitride not only decreases the chlorine gas usage but also reduces the waste generation, and makes the present route more feasible and sustainable 1,2,7 . TiOxCyNz can be produced from the carbothermal reduction and nitridation (CTRN) of ilmenite (FeTiO3) 2,4,9 . In this paper, the optimum conditions for TiCl4 formation from the chlorination process of TiOxCyNz powder and chlorine gas generation from the reaction between HCl and KMnO4 were investigated.…”

“…Chlorination process is a crucial step in titanium tetrachloride (TiCl4) and highly purified titanium dioxide (TiO2) pigment production 1,2 . Recently, titanium oxycarbonitride (TiOxCyNz) was used as an intermediate phase for TiCl4 production instead of the conventional chlorination using high titanium dioxide (TiO2) feedstocks [3][4][5][6][7] .…”