Cuprous chromite

Cupric chromite Cuprous chromite Cuprous oxide... 

The intermediate precipitate obtained by the reaction of copper nitrate with ammonium dichromate and ammonia has been shown to be Cu(0H)NH4Cr04,122 and the decomposition of the precipitate to give the catalyst to be formulated as in eq. 1.6, by an X-ray diffraction study by Stroupe, although the catalysts obtained by decomposition at sufficiently controlled low temperature (350°C) are amorphous.123 Catalysts previosly used in liquid-phase hydrogenation below 300°C often show crystalline cupric chromite to have been largely reduced to the cuprous chromite... 

Cuprous Chromite, CUaO.CrjOj, yields steel-blue crystals, density 5-24. ... 

Among the cuprous compounds which have been studied by X-ray methods, linear coordination is quite rare but it does occur in cuprite, Cu20 (100), which is isostructural with argentous oxide, and in cuprous chromite (33) and ferrite (127). In these three linearly coordinated oxide structures,... 

J. F. Persoz obtained cuprous chromite, CuCr02, by calcining cupric chromate in a crucible exposed to the reducing action of the furnace gases, and extracting the product with hydrochloric acid and L. and P. Wohler obtained it by heating one of the basic cupric chromites with an excess of cupric oxide above 900°, and... 

Cuprous oxide is also reduced violently by electropositive metals as discovered in an accident which occurred with aluminium. With chromium (III) oxide the reaction enables one to make copper chromite, which is a very common catalyst. The activity of copper chromite is such that it frequently combusts at the end of the reaction. 

Catalyst, alumina, 34, 79 35, 73 ammonium acetate, 31, 25, 27 copper chromite, 31, 32 36, 12 cuprous oxide-silver oxide, 36, 36, 37 ferric nitrate, hydrated, 31, 53 piperidine, 31, 35 piperidine acetate, 31, 57 Raney nickel, 36, 21 sulfuric acid, 34, 26 Catechol, 33, 74 Cetylmalonic acid, 34, 16 Cetylmalonic ester, 34,13 Chlorination, by sulfuryl chloride, 33, 45 ... 

K. Fischbeck and E. Einecke found that the cathodic polarization of ferrous, cuprous, calcium, and magnesium chromites produces chromic acid, whilst the other chromites are unaffected, and natural chrome ironstone behaves in a like manner, but other commercial chromites are reduced on cathodic polarization, and yield chromic acid on anodic polarization. Chromites behave as an intermediate electrode. 0. Unverdorben observed that chromyl fluoride, prepared by heating a mixture of fluorspar, lead chromate, and sulphuric acid, when passed into water, furnishes an aq. soln. of this oxide. The soln. was treated with silver nitrate, and the washed precipitate of silver chromate decomposed by hydrochloric acid. A. Mans said that anhydrous sulphuric acid or fuming sulphuric acid is not suited for the preparation because of its volatilization with the chromyl fluoride. 

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