Chromite Fines

Refractory-grade chromite is used for manufacturing magnesia-chrome bricks used in the extractive metallurgy of platinum group metals. Foundry sands made of chromite fines are used for making mould used for casting nonferrous metals. 

Zhu Deqing, et al, Sintering behaviours of chromite fines and the consolidation mechanism Int. J. Miner. ProceM,86(2008),58-67. 

Zhu Deqing Li Jian, Fan Xiaohui, et al, Literature review of the agglomeration of chromite fines Sintering and Pelletizing,29(2)(2004),27-30. 

PROCESS OPTIMIZATION BY RESPONSE SURFACE METHOD EOR SINTERING OF CHROMITE FINES BY MICROWAVE... 

This experiment uses the South African chromite fines as sintering raw material, particles smaller than 75gm. Add bentonite as binder and its accessing amount is decided by the response surface methodology design experiment. Sintering the feed in microwave field after blend well. 

According to the obtained analysis results of Table IV and V, the above model can accurately predict the compressive strength and shatter strength of chromium sintered ore from microwave sintering chromite fines experiment in the experimental study level range of impact factor. 

Central composite design experiment and response surface analysis indicate that sintering temperature, sintering time, and binder addition amount have an impact on the strength of chromite fines sintered products, and the regression formulas are ... 

Jia Zhenhai, Pretreatment technology of Chromite Fines[J]. )Feiro-Alloys 1989, (3)) 39 —40. 

Wei Wen et al., Direct reduction process and dedicated crucible of chromite fines by microwave [P]. (Chinese Patent 102051482, 2010.12.17). 

Tai TW and Lessing PA. Modified resin-intermediate of perovskite powders. Part II. Processing for fine, nonagglomerated strontium-doped lanthanum chromite powders. J. Mater. Res. 1992 7 511-519. 

To continue the process, the fatty methyl esters are phase-separated from the glycerin (or glycerol—same thing, just to keep you on your toes), washed with water to remove any trace amounts of methanol and glycerin and dried. In a second reaction, the methyl esters are hydrogenated to get the fatty alcohols (in the southeast corner of Figure 15—2). The catalyst is usually a mixture of cupric chromite and cupric oxide in the form of a finely divided powder. Conversion of the triglycerides is about 95%. 

The hydrogenation of carbonyl groups in compounds containing ethylenic bonds to obtain the corresponding unsaturated alcohols is a very important reaction in the fine chemicals field. Extensive work has been carried out to develop heterogeneous catalysts for these reachons, copper chromite being one of the first systems studied [69, 70]. Transihon metals are widely used catalysts for these reachons. 

Chromiumflll) oxide is amphoteric. Although insoluble in water, it dissolves in acid to produce hydrated chromium ion, [Cr(H20)6] +. It dissolves in concentrated alkah to yield chromite ion. When heated with finely divided aluminum or carbon it is reduced to chromium metal ... 

MgO, and sulfur and phosphorus content. In some operations high-grade ore is selectively mined, hand sorted and screened, and sold as lump and fines. More commonly the high-grade lump material is removed by hand, and the reminder is crushed and ground before beneficiation. LIBS may be used for chromite sorting and Mg, Al, Si contents evaluation (Fig. 8.12). 

Preparation of Potassium Chromate. (Perform one experiment on each table.) Melt a mixture of 1 g of potassium carbonate, 1 gof potassium hydroxide, and 2 g of potassium nitrate in an iron crucible by heating with the flame of a burner. While stirring the melt with an iron wire, introduce 1 g of finely comminuted chromite or -0.8 g of chromium oxide into the crucible. Roast the mixture for 5-10 minutes on a blowpipe. Treat the cooled melt with water. Filter the solution and evaporate it until a crystalline film appears. What is the composition of the formed crystals Why was potassium carbonate introduced into the reaction Write the equation of the reaction. 

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