The reduction of stannic oxide with carbon

Padilla, R.; Sohn, Hong Yong

doi:10.1007/bf02653980

Cited by 61 publications

(56 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…(1)- (3). For the metallic oxide-carbon (or carbides) reduction system, it is generally believed that indirect reactions prevail during the whole course of the reduction 9,[22][23][24][25][26][27] and a coupling phenomenon of carbon gasification and metal oxide reduction takes place.…”

Section: Theoreticalmentioning

confidence: 99%

Carbothermic Reduction of Synthetic Chromite with/without the Addition of Iron Powder

Teng

Wang

et al. 2016

ISIJ Int.

View full text Add to dashboard Cite

Carbothermic reduction of chromite is an important industrial process for extracting chromium from the chromite. To have a better understanding of the effect of iron on the carbothermic reduction of chromite, the reduction of synthetic chromite (FeCr 2 O 4 ) by graphite with/without the addition of iron powder was investigated in this paper by Thermogravimetric Analysis (TGA) in argon atmosphere. The fractional reduced samples were examined by SEM/EDS and XRD analysis, and the reduction process was thermodynamically and kinetically evaluated. The experimental results show that the iron powder addition enhances the reduction of FeCr 2 O 4 and this effect increases when increased amounts of iron powder are added. This phenomenon is attributed to the in situ dissolution of chromium into the iron and mixed carbide (Cr,Fe) 7 C 3 , which can decrease the activity of the nascent chromium formed by the reduction of the FeCr 2 O 4 . The experimental results indicate that the reduction of FeCr 2 O 4 with up to 80 wt.% iron powder addition is likely to be a single-step process and the kinetic analysis suggests that the reduction reaction is likely to be either (a) chemical reaction at the surface of FeCr 2 O 4 or (b) diffusional dissolution of the product (FeCr 2 ) into the iron/alloy particles or the mixed control of (a) and (b).

show abstract

Section: Theoreticalmentioning

confidence: 99%

Carbothermic Reduction of Synthetic Chromite with/without the Addition of Iron Powder

Teng

Wang

et al. 2016

ISIJ Int.

View full text Add to dashboard Cite

show abstract

“…[12,13,14] Consequently, it is conceivable that mixtures of MoS 2 -C can react at high temperatures forming gaseous species such as CS 2 and CS in equilibrium with condensed phases. In the temperature range of interest, 700 ЊC to 1400 ЊC, the stable molybdenum solid phases that can be found are MoS 2 , Mo 2 S 3 , Mo, MoC, and Mo 2 C. [15,16] Therefore, the direct reduction of molybdenite by carbon will be governed by the prevailing chemical equilibrium between these phases and the reaction kinetics.…”

Section: Mos 2 -C Systemmentioning

confidence: 99%

Reduction of molybdenite with carbon in the presence of lime

Padilla

Ruiz

Sohn

1997

Metall Mater Trans B

Self Cite

View full text Add to dashboard Cite

The thermodynamics of the MoS 2 -C-CaO system has been studied in order to understand the carbothermic reduction of molybdenite in the presence of CaO. Kinetic studies were also conducted with mixtures of MoS 2 ϩ C ϩ CaO in the temperature range of 900 ЊC 1200 ЊC. The reduction of MoS 2 with carbon in the presence of lime proceeds through the direct oxidation of MoS 2 by CaO to form intermediate molybdenum oxidized species, MoO 2 and CaMoO 4 , which subsequently undergo reduction by CO to yield mixtures of Mo, Mo 2 C, and CaS. Complete conversion of MoS 2 can be obtained at 1200 ЊC in less than 20 minutes for molar concentrations of MoS 2 :C:CaO ϭ 1:2:2. The kinetic model ln (1 Ϫ X) ϭ kt was used to determine the rate constants. The activation energy found for the temperature range studied was 218.8 kJ/mol.

show abstract

“…[1][2][3] At the present time, approximately 2 tonnes of carbon dioxide are reported to be generated for the production of 1 tonnes of tin metal. 4) In general, the carbon dioxide is well known to be a major gas of the greenhouse gases.…”

Section: Introductionmentioning

confidence: 99%

Reduction of SnO<SUB>2</SUB> with Hydrogen

et al. 2011

View full text Add to dashboard Cite

This study deals with the reduction of tin oxide by hydrogen in the temperature range of 773$1023 K and the hydrogen partial pressure of 30:4$101:3 kPa. It aims to investigate the kinetics of the reaction between tin oxide and hydrogen. The hydrogen reduction of tin oxide is to be related with the efforts to extract tin metal with decreasing the emission of carbon dioxide which causes global warming. The experiments were carried out under isothermal condition in hydrogen atmosphere using TGA equipment. The reduction rate of tin oxide to tin metal by hydrogen was found to be relatively fast under the whole conditions until the reduction ratio of SnO 2 approaches to about 0.95. As an example, at 1023 K under a hydrogen partial pressure of 101.3 kPa, almost 100% of tin oxide was reduced to tin metal in 10 min. The nucleation and growth model yielded a satisfactory fit to these experimental data. The reaction was first order with respect to hydrogen partial pressure and had an activation energy of 62.5 kJ/mol (15.0 kcal/mol).

show abstract

The reduction of stannic oxide with carbon

Cited by 61 publications

References 14 publications

Carbothermic Reduction of Synthetic Chromite with/without the Addition of Iron Powder

Carbothermic Reduction of Synthetic Chromite with/without the Addition of Iron Powder

Reduction of molybdenite with carbon in the presence of lime

Reduction of SnO<SUB>2</SUB> with Hydrogen

Contact Info

Product

Resources

About