@article{Bondarenko_Matviichuk_2017, title={COMPUTER MODELING OF CHEMICAL EQUILIBRIUMS IN WO3–H2O SYSTEM}, url={https://etars-journal.org/index.php/journal/article/view/103}, DOI={10.33070/etars.4.2017.06}, abstractNote={<p>Detail investigation of equilibrium chemical reactions in WO<sub>3</sub>–H<sub>2</sub>O system using computer program FacktSage with the aim to establish influence of temperature and quantity of water on formation of compounds of H<sub>2</sub>WO<sub>4</sub> and WO<sub>2</sub>(OH)<sub>2</sub> as well as concomitant them compounds, evaporation products, decomposition and dissociation, that are contained in the program data base were carried out. Calculations in the temperature range from 100 to 3000 °С were carried out. The amount moles of water added to 1 mole of WO<sub>3</sub> was varied from 0 to 27. It is found that the obtained data by the melting and evaporation temperatures of single-phase WO<sub>3</sub> are in good agreement with the reference data and provide additionally detailed information on the composition of the gas phase. It was shown that under heating of 1 mole single-phase WO<sub>3</sub> up to 3000 °С the predominant oxide that exist in gaseous phase is (WO<sub>3</sub>)<sub>2</sub>. Reactions of it formation from other oxides ((WO<sub>3</sub>)<sub>3</sub> and (WO<sub>3</sub>)<sub>4</sub>) were proposed. It was established that compound H<sub>2</sub>WO<sub>4</sub> is stable and it is decomposed on WO<sub>3</sub> and H<sub>2</sub>O under 121 °C. Tungsten Oxide Hydrate WO<sub>2</sub>(OH)<sub>2</sub> first appears under 400 °С and exists up to 3000 °С. Increasing quantity of Н<sub>2</sub>О in system leads to decreasing transition temperature of WO<sub>3</sub> into both liquid and gaseous phases. It was established that adding to 1 mole WO<sub>3</sub> 26 mole H<sub>2</sub>O maximum amount (0,9044–0,9171 mole) WO<sub>2</sub>(OH)<sub>2</sub> under temperatures 1400–1600 °С can be obtained, wherein the melting stage of WO<sub>3</sub> is omitted. Obtained data also allowed to state that that from 121 till 400 °С WO<sub>3</sub>–Н<sub>2</sub>O the section in the О–W–H ternary system is partially quasi-binary because under these temperatures in the system only WO<sub>3</sub> and Н<sub>2</sub>O are present. Under higher temperatures WO<sub>3</sub>–Н<sub>2</sub>O section becomes not quasi-binary since in the reaction products WO<sub>3</sub> with Н<sub>2</sub>O except WO<sub>3</sub> and Н<sub>2</sub>O, there are significant amounts of WO<sub>2</sub>(OH)<sub>2</sub>, (WO<sub>3</sub>)<sub>2</sub>, (WO<sub>3</sub>)<sub>3</sub>, (WO<sub>3</sub>)<sub>4</sub> and a small amount of atoms and other compounds. <em>Bibl. 12, Fig. 6, Tab. 5.</em></p&gt;}, number={4}, journal={Energy Technologies & Resource Saving}, author={Bondarenko, V.P. and Matviichuk, O.O.}, year={2017}, month={Dec.}, pages={35-48} }