Lime-scavenged reduction of molybdenite

Prasad, P. M.; Mankhand, T R; Rao, P.

doi:10.1016/0892-6875(93)90059-v

Cited by 17 publications

(9 citation statements)

References 19 publications

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“…Prasad et al [26] did not report finding any calcium molybdate in phase identification of their reacted samples as analysis by XRD at 1173 K. They used high grade and low-grade molybdenite concentrate with commercial grade lime in the form of fine powders for the reaction. It is quite possible that their reaction conditions were such to avoid the molybdate phase region; either because the fine powder reactants and the gases were ultra-dry or contact between water vapor and the powders was negligible.…”

Section: Introductionmentioning

confidence: 96%

Reaction kinetics of direct hydrogen reduction of molybdenum disulfide in the presence of lime: A single pellet experimental investigation

Afsahi

Kumar

Sohrabi

et al. 2014

Chemical Engineering and Processing: Process Intensification

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Section: Introductionmentioning

confidence: 96%

Reaction kinetics of direct hydrogen reduction of molybdenum disulfide in the presence of lime: A single pellet experimental investigation

Afsahi

Kumar

Sohrabi

et al. 2014

Chemical Engineering and Processing: Process Intensification

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“…The preceding reaction appears to be an appropriate sumers [10,11] who found that it is indeed feasible to achieve the mation of two successive solid-gas reactions [2] and [3] simultaneous reduction-carburization of MoS 2 resulting in (Table I). From a thermodynamic viewpoint, the reductionthe formation of 98 pct purity molycarbide.…”

Section: Introductionmentioning

confidence: 99%

Kinetics of the direct synthesis of molycarbide by reduction-carburization of molybdenite in the presence of lime

Prasad

Mankhand

Rao³

et al. 2002

Metall Mater Trans B

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Kinetic studies were conducted on the carbon monoxide reduction of molybdenite in the presence of lime. Contrary to the expectation that the MoS 2 (s) ϩ CaO (s) ϩ CO (g) reaction will result in metal formation, molycarbide was found to form and no Mo was detected in the product. This is explained on the basis of thermochemical considerations, which indicate that the Mo 2 C formation is more feasible by eight orders of magnitude. The effects of quantity of lime in the charge, CO flow rate, temperature (1123 to 1298 K), and time of reduction have been studied. Kinetic analysis reveals that the results on the MoS 2 (s) conversion to Mo 2 C (s) fit into a modified parabolic rate law. Based on the thermochemical calculations and experimental findings, the probable reaction scheme has been identified. Molycarbide appears to form by a three-successive solid-gas reaction path consisting of (1) metal formation by the MoS 2 (s) ϩ CO (g) reaction followed by (2) in-situ carburization of Mo metal by CO (g), and finally (3) the scavenging of the COS (g) by lime, resulting in CaS (s). The latter two reactions drive the overall reaction forward. Further, out of these three consecutive reactions, progress of the overall MoS 2 ϩ CaO ϩ CO reaction seems to be governed by the intrinsic kinetics of the first one. Calcium molybdate, which forms as a transitory phase, plays a significant role by modifying the linear kinetics of the MoS 2 (s) ϩ CO (g) to one of parabolic nature.

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“…No references were found on modeling for CMCs, though experimental studies o ing process have been reported. Studies o derived SiC ceramic 25 and SiC/SiC c shown that porosity decreases and mecha prove with the increasing number of PIP show that increasing pyrolysis temperatu tration of SiC fillers in polycarbosilane improved mechanical properties in two-d SiC (C/SiC) composites fabricated using Starting with pyrolysis of a "cured prepreg-based composite, each processin process involves infiltration of a precera porous ceramic preform followed by a py which the polymer is converted into ceram cess modeling is focused on these two ste Modeling of infiltration of liquids in well-studied subject, especially in the where it is used to model seepage of wa soils and rocks. 29,30 The physics of resin under pressure is similar to the seepage pr lar approaches have been used also to mod into a mold containing fiber mats.…”

Section: Introductionmentioning

confidence: 99%

A novel sulfur‐emission free route for preparing ultrafine MoSi₂ powder by silicothermic reduction of MoS₂

2021

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The extraction of metal from sulfide mineral is usually accompanied by the emission of sulfur-containing gas (e.g., SO 2 ), which will cause serious pollution to the environment. In this work, a sulfur-emission free route for preparing ultrafine molybdenum disilicide (MoSi 2 ) powder by silicothermic reduction of MoS 2 with the desulfurization agent of lime was proposed. The internal MoS 2 -Si mixture is wrapped in an external desulfurization layer composed of lime. After the reaction is completed, the prepared MoSi 2 can be easily separated from the desulfurization layer by using a non-chemical method. In addition, when the reaction temperature is higher than 1000°C, almost all S in MoS 2 is transformed to sulfurcontaining gas SiS, which can be fully captured by lime to generate CaS, Si, and CaSiO 3 . For the raw material with a MoS 2 :Si molar ratio of 1:4, after reacting at 1000, 1100, and 1200°C for 2 h, the average grain sizes of the obtained MoSi 2 powder are approximately 100, 300, and 800 nm, respectively. Moreover, when the reaction time is prolonged from 2 to 6 h at 1000°C, the average grain size of the acquired MoSi 2 powder is about 200 nm, and the residual sulfur content is about 0.12%. This work provides a new insight to extract metals or metal compounds from sulfide ores without releasing sulfur-containing gas.

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Lime-scavenged reduction of molybdenite

Cited by 17 publications

References 19 publications

Reaction kinetics of direct hydrogen reduction of molybdenum disulfide in the presence of lime: A single pellet experimental investigation

Reaction kinetics of direct hydrogen reduction of molybdenum disulfide in the presence of lime: A single pellet experimental investigation

Kinetics of the direct synthesis of molycarbide by reduction-carburization of molybdenite in the presence of lime

A novel sulfur‐emission free route for preparing ultrafine MoSi₂ powder by silicothermic reduction of MoS₂

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Lime-scavenged reduction of molybdenite

Cited by 17 publications

References 19 publications

Reaction kinetics of direct hydrogen reduction of molybdenum disulfide in the presence of lime: A single pellet experimental investigation

Reaction kinetics of direct hydrogen reduction of molybdenum disulfide in the presence of lime: A single pellet experimental investigation

Kinetics of the direct synthesis of molycarbide by reduction-carburization of molybdenite in the presence of lime

A novel sulfur‐emission free route for preparing ultrafine MoSi2 powder by silicothermic reduction of MoS2

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A novel sulfur‐emission free route for preparing ultrafine MoSi₂ powder by silicothermic reduction of MoS₂