Copper-chromite composition

When it is desirable to use a weak black, bone black may be substituted for carbon. It is manufactured by calcining animal bones and contains approximately 85% calcium phosphate and calcium carbonate. Black iron oxide (Fe O is stable up to 150°C. Copper chromite black (Cu(Cr02)2) is iuert to all but mbberlike compositions and has been calcined to 600°C. 

Modification of the burning rates, pressure exponents, and temp coefficients of burning rate of the fluorocarbon composites has been accomplished with copper, lead, tin, sodium, ammonium and potassium fluoborates sodium, potassium, lithium, lead, copper and calcium fluorides potassium and ammonium dichromate lead and zinc stearate cesium carbonate potassium and ammonium sulfate copper chromite oxides of magnesium, copper and manganese boron zinc dust and carbon black (Ref 75)... 

Horton (H9, H10) has obtained additional acoustic-admittance data for a series of composite propellants. At a given frequency, decreasing the mean oxidizer particle size increases the acoustic admittance and thereby the tendency for instability. Horton also investigated the effects on the acoustic admittance of the incorporation of traces of copper chromite, a known catalyst, for the decomposition of ammonium perchlorate, lithium fluoride (a burning-rate depressant), and changes in binder these data are difficult to analyze because of experimental errors. 

Gombustion catalysts are needed to obtain complete combustion of AN composite propellants. Ghromium compounds such as chromium trioxide (Gt203), ammonium dichromate ((NH4)2Ct207), and copper chromite (CuCr204) are known to... 

This was followed by Taback s (94) study of the effect of copper chromite catalyst additives. In general, the results of these investigations fitted the Summerfield relation remarkably well over the range 1—100 atm. (Figures 3 and 6). Moreover, the effects of propellant composition and oxidizer particle size on the constants a and b, respectively, were consistent with qualitative predictions from the theory. Similar results have since been obtained by Yamazaki (101), Marxman (18), and the group at ONERA (8, 52, 64) in France (Figure 7). An alternative to the above equation has been proposed by Penner et al. (68)—i.e., (1/r)2 = (a/p)2 + (b/pm)2. A systematic survey (91) of all available data shows that when... 

The catalysts (lead and copper salts of aromatic acid in combination with carbon black) which were effective for DB and RDX-CMDB propellants were also found effective for dinitropiperazine (DNP) containing CMDB propellants [259]. Copper chromite (CC) and ferric oxide which are generally used for ballistic modification of composite propellants are also effective for CL-20-based aluminized CMDB propellants. However, CC is a better BRM [260]. 

Copper chromite is the reaction product of copper oxide and chromium oxide. It is an important catalyst for the burning of rocket propellants and pyrotechnical compositions. 

Figure 1. Total surface area and theoretical copper chromite surface area of samples fired 1 hr at 600°C as a function of composition...

Copper-chromite type catalysts supported by alumina or graphite and promoted with barium were used for the one step synthesis of tertiary fatty amines (R2NCH3 or RN(CH3)2) from nitrile, methanol and hydrogen. The surface composition of the catalysts was studied by XPS and by adsorption experiments. A correlation was found between the selectivity and the presence of a well-dispersed CUC1O2 phase, stabilized with barium. Moreover the elements influencing the stability of the copper catalysts were also studied and we remarked the effect of the promoter or/and of the support on the variation of the copper surface area in the presence of water or ammonia. These modifications were examined in relation with the change of the catalytic properties with time-on-stream. 

Copper chromite, CuCr204, was prepared by thermal decomposition of copper-chromium hydroxycarbonate in air at 900 C. The hydroxycarbonate was coprecipitated fiom a solution of the metal nitrates at constant pH and temperature. The chemical composition of the sample was confirmed by AAS method. 

Phase composition of the samples treated in H2. No noticeable change in the X-ray pattern of copper chromite is observed upon in situ reduction with H2 up to - 200°C. The rise in T is accompanied by the appearance of the Cu metal phase, with particle size of 100 A. The quantity of copper increases witb rising T, and at T = 320°C, the degree of reduction reaches 50% (taken per total... 

Supported copper-chromium oxide catalysts. The non-modified support after its thermal treatment at 773 K, if coated with a 7% (Cu+Cr) mixture, seems to contain a series of spinel-type phases on the base of the support and copper chromite structures as well. Then diffractogramms of the sample are characterized by distorted lines of the support only. After thermal treatment at 1273 K, there coexist a-Al203 with the increased cell parameter and aluminium-copper-chromium spinel with a = 8.098 A, which is typical for Cu(Ali 8Cro.2)04 composition. No lines of copper (+1), i.e. Cu2Cr204 and CU2AI2O4, are observed. 

When Adkins tried to modify the Lazier recipe and make a copper chromite hydrogenation catalyst, he found that an active black cupric oxide was produced instead of the red oxide claimed by Lazier. Adkins and Folkers subsequently suggested modifications to the recipe, including the addition of barium, magnesium, or calcium oxides to stabilize the black oxide form, which was more active. Atypical recipe and catalyst composition is shown in Table 3.11. 

This is a grey-black or black copper compound with composition CuCt204 (also termed cupric chromite). It is also a component in a brown-black or black copper-chromium oxide pigment mentioned in the pigment hterature and said to be a mixture of CuCr204 and CuO. 

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