Thermodynamic Analysis of Extraction of Synthetic Rutile from Modified Slag

Abstract

In this work, a new technique of modified-alkali leaching−dilute acid washing for extracting synthetic rutile from high-titanium slag is proposed. Most of the Ti components are enriched into the rutile phase during the modification, and rutile can be separated by alkali leaching−dilute acid washing. Thermodynamic analyses of the reactions occurring during the alkali leaching−dilute acid washing process were performed to provide a theoretical basis for rutile extraction from the modified slag. The calculated thermodynamic results suggest that it is possible to use the alkali leaching−acid washing process to separate rutile from the impurities in the modified slag. The structure of the glass phase, which contains almost all of the impurities, requires relatively high alkalinity to be destroyed, and the impurities of the slag, including Fe 2 O 3 , CaO, MgO, and MnO, can be removed easily with dilute acid after the alkali leaching stage. The technique is low in cost and obtains synthetic rutile for the chlorination process.

A Clean Process to Prepare High-Quality Acid-Soluble Titanium Slag from Titanium Middling Ore

“…The feasibility of the alkali leachingdilute acid washing process was evaluated by means of thermodynamic analysis. According to the relevant investigations [18][19][20][21][22][23][24], binary potential pH diagrams for Si-H2O, Al-H2O, Mg-H2O, V-H2O, Ca-H2O, Fe-H2O and Mn-H2O systems have been reported. It was found that Al2O3, MgO, V2O5, VO2, CaO, FeO and MnO could be leached by dilute acid, and SiO2 could be leached by alkali.…”

“…According to the relevant literature [24] and Figure 3, it can be seen that SiO 2 and Al 2 O 3 in the slag can be theoretically leached by alkali. Thus, the TiO 2 content in the slag, SiO 2 extraction ratio and Al 2 O 3 extraction ratio were determined by chemical analysis.…”

“…The feasibility of the alkali leaching-dilute acid washing process was evaluated by means of thermodynamic analysis. According to the relevant investigations [18][19][20][21][22][23][24] The objective of this study is to prepare high-quality acid-soluble titanium slag by a direct reduction-magnetic separation-alkali leaching-dilute acid washing method and simultaneously realize the comprehensive utilization of titanium middling ore. For optimizing leaching conditions, the effects of operating parameters on TiO 2 content and impurity oxides extraction ratios in the titanium slag were investigated. In order to understand the leaching mechanism, the chemical and phase compositions of low-grade titanium slag, the cake after alkali leaching and the cake after alkali leaching-dilute acid washing were determined by chemical analysis and XRD technology.…”

Decomposition characteristics of compound additive and effect of roasting atmosphere on vanadium extraction from stone coal

“…[11][12][13] Most of these additives would be decomposed and release gasses during roasting. [14,15] Therefore, the roasting atmosphere includes not only oxygen but also the decomposition gas of additives. [16] However, the investigations on the decomposition characteristics of additives and the effect of the gasses decomposed from additives on vanadium recovery were seldom involved.…”

Co-modification and Crystalline-control of Ti-bearing Blast Furnace Slags

“…The separated rutile from slags can be further treated through hydrochloric acid leaching method for TiO 2 white pigment production or used as raw materials in titanium metallurgy. [10][11][12][13] The most important considerations of SCPS method are the selection and formation of Ti-enriched phases. The primary crystalline phase of the industrial Ti-BF slags is perovskite, the crystallization behaviors of which have been studied by many researchers.…”