Kinetic study of the isothermal and non-isothermal chlorination of a scheelite–wolframite concentrate with chlorine and sulphur dioxide

Non-isothermal coal char gasification with CO 2 in a micro fluidized bed reaction analyzer and a thermogravimetric analyzer

“…The non-isothermal gasification of char is usually 68 conducted by exposing a sample to a programmed reaction tem- 69 perature variation, which reveals the gasification behavior of char 70 under different temperatures and clarifies the relationship 71 between heating rate and reaction characteristics [9]. Compared 72 with the isothermal method, the non-isothermal method is simple 73 and easy because of avoiding the change of chemical and physical 74 properties of the tested sample, and providing useful information 75 via fewer experiments [10][11][12]. However, due to the dependence 76 of heating rate, the experimental data tested from non- 77 isothermal method are always difficult to analyze, resulting in 78 obvious deviation in kinetic parameters [13].…”

Kinetic study of Hubnerite (MnWO4) chlorination

“…They have been working mainly with Wolframites, including a wide range of the ratio of divalent metals (Fe/Mn + Fe-WO 4 (s)), and Scheelite (CaWO 4 (s)). In a previous paper, Menéndez et al [16] submitted a study about the main kinetic aspects of the isothermal and non-isothermal chlorination of a Scheelite ± Wolframite concentrate with chlorine and sulphur dioxide. On that occasion, they proposed a rate equation based on a diffusion mechanism with spherical symmetry, which was determined with both methods.…”

Intrinsic Kinetics of Chlorination of WO3 Particles With Cl2 Gas Between 973 K and 1223 K (700 °C and 950 °C)

“…[10] Some work on the extraction of tungsten from mineral ores by chlorination has been published. [13][14][15][16] It is estimated that, approximately one third of tungsten consumption worldwide originates from reclaimed tungsten, with this percentage being much higher in market economy countries. [11] The increased availability of contaminated powder or mixed-up sintered scrap requires the development of chemical methods for the recovery of the individual constituents.…”