Copper ammonium molybdates

Molybdenum is also recovered as a by-product of copper and tungsten mining operations. The metal is prepared from the powder made by the hydrogen reduction of purified molybdic trioxide or ammonium molybdate. 

Similarly, copper(II) 1,8,15,22-tetraazaphthaIocyanine can be made from copper(II) chloride, pyridine-2,3-dicarboxylic acid, and urea in the presence of a catalytic amount of ammonium molybdate(VI), heated to 210DC for 4-5 hours, in a yield of 52%.459... 

The first example of a heterogeneously catalyzed hydroamination of an alkene appeared in a 1929 patent in which it is claimed that NHj reacts with ethylene (450°C, 20 bar) over a reduced ammonium molybdate to give EtNH2 [24]. An intriguing reaction was also reported by Bersworth, who reacted oleic acid with NH3 in the presence of catalysts like palladium or platinum black or copper chromite to give the hydroamination product in quantitative yields [25]. However, this result could not be reproduced [26]. 

Drinking water with Mo as ammonium molybdate. Basal diet with 13 mg copper/kg and 2900 mg sulfur/kg... 

Modras (51) reported spot test reactions to differentiate hydralazine from closely related drugs. Reagents used were aqueous copper (I) chloride, aqueous ammonium molybdate, iodine in potassium iodide solution, aqueous cobalt (II) nitrate, alcoholic ninhydrin, and alcoholic bromophenol blue. The tests were performed on paper or on Silica Gel G. 

The reactants are phthalic anhydride, urea and copper(n) chloride, which are heated in a high-boiling aromatic solvent such as 1,2,4-trichlorobenzene, nitrobenzene or m-dinitrobenzene in the presence of a catalyst, usually ammonium molybdate. The solvent also acts as a heat-transfer medium. On heating to 120 °C an exothermic reaction begins and this temperature is maintained for about an hour. The temperature is then raised to 160-180 °C and kept constant for 6-12 hours. During this time ammonia and carbon dioxide are evolved, together with some solvent the reaction is complete when ammonia evolution ceases. The remaining solvent is then removed by either steam or vacuum distillation. The yield is 90-95%. For many years the solvent process was in almost exclusive use. 

The solvent process involves treating phthalonitrile with any one of a number of copper salts in the presence of a solvent at 120 to 220°C [10]. Copper(I)chloride is most important. The list of suitable solvents is headed by those with a boiling point above 180°C, such as trichlorobenzene, nitrobenzene, naphthalene, and kerosene. A metallic catalyst such as molybdenum oxide or ammonium molybdate may be added to enhance the yield, to shorten the reaction time, and to reduce the necessary temperature. Other suitable catalysts are carbonyl compounds of molybdenum, titanium, or iron. The process may be accelerated by adding ammonia, urea, or tertiary organic bases such as pyridine or quinoline. As a result of improved temperature maintenance and better reaction control, the solvent method affords yields of 95% and more, even on a commercial scale. There is a certain disadvantage to the fact that the solvent reaction requires considerably more time than dry methods. 

Phthalic anhydride and urea, together with copper(I)chloride and ammonium molybdate, are heated to 200°C in trichlorobenzene. The ratios between the components are the same as in the baking process. Carbon dioxide and ammonia are released to yield Copper Phthalocyanine Blue. The reaction is complete after 2 to 3 hours, producing a yield between 85% and more than 95%. 

Despite the expenditure of a tremendous amount of effort throughout the world, the two original methods employed in the manufacture of copper phthalocyanine are still used. In the first, a mixture of phthalic anhydride, urea and copper(I) chloride is heated in a high-boiling solvent such as nitrobenzene or trichlorobenzene in the presence of a catalytic amount of ammonium molybdate. The crude copper phthalocyanine is filtered off and the solvent recovered by distillation. The urea acts as a source of nitrogen and the first step in the overall reaction (equation 18) is conversion of phthalic anhydride to phthalimide (219) by ammonia liberated by the urea. More ammonia then converts the phthalimide to l-keto-3-iminoisoindoline (220) and finally to l-amino-3-iminoisoin-dolenine (221). All three intermediates have been isolated and identified. In the presence of copper chloride the l-amino-3-iminoisoindolenine undergoes conversion to the copper complex of phthalocyanine. 

Alternatively, the compound can be obtained by letting the deep-red solution, obtained after mixing the solutions, stand at room temperature for 2-4 hours. In this case the product is usually contaminated with crystals of ammonium tetrathio-molybdate(VI), (NH4)2MoS4. The compound also can be obtained in poor yields by dissolving freshly precipitated copper(II) sulfide in ammoniacal ammonium molybdate solution saturated with hydrogen sulfide. Undissolved copper(II) sulfide is removed by filtration after 3-5 minutes, and the copper(I) ammonium thiomolybdate(VI) is obtained by boiling as above. 

Ground together a mixture of phthalic anhydride (10 mmol, 1.54 g) and copper chloride (2.5 mmol, 0.425 g) and put it to a clean reaction vessel together with urea (1.2 g. 20 mmol), and ammonium molybdate (0.47 g, 2.0 mmol). 

Two processes are commonly used for the production of copper phthalocyanine the phthalic anhydride-urea process patented by ICI [33,34] and the I.G. Farben dinitrile process [48], Both can be carried out continuously or batchwise in a solvent or by melting the starting materials together (bake process). The type and amount of catalyst used are crucial for the yield. Especially effective as catalysts are molybdenum(iv) oxide and ammonium molybdate. Copper salts or copper powder is used as the copper source [35-37] use of copper(i) chloride results in a very smooth synthesis. Use of copper(i) chloride as starting material leads to the formation of small amounts of chloro CuPc. In the absence of base, especially in the bake process, up to 0.5 mol of chlorine can be introduced per mole of CuPc with CuCl, and up to 1 mol with CuCl2. 

As apparatus for the batch process, an enamel or steel reactor with an agitator and pressure steam or oil heating suffices. Apparatuses used in the continuous synthesis in the presence of solvents and in the bake process are described in [50] and [51,52], respectively. The choice of process depends on the availability and cost of the starting materials phthalodinitrile or phthalic anhydride. Although the phthalodinitrile process has certain advantages over the phthalic anhydride process, the latter is preferred worldwide because of the ready accessibility of phthalic anhydride. In this process the molar ratio of phthalic anhydride, urea, and cop-per(i) chloride is 4 16 1, with ammonium molybdate as catalyst. The mixture is heated in a high-boiling solvent such as trichlorobenzene, nitrobenzene, or kerosene. The solvent is removed after the formation of copper phthalocyanine. Fre-... 

Hypophosphite. (i) Silver nitrate solution test (IV.31, 1), copper sulphate solution test (IV.31, 4), and ammonium molybdate test (IV.31, 9). 

Heavy-metal ions, such as those of mercury, silver, copper, and lead inhibit alpha-amylases in general, mercury is more effective than copper or lead. fllphfl-Amylases from higher plants are also inhibited by ammonium molybdate and L-ascorbic acid. The mechanism of inhibition is not yet known. 

Preparation.—Although the purest molybdenum is obtained from wulfenite, the chief commercial source is molybdenite, which is converted into the trioxide by roasting in air either with or without the addition of sand, and, on dissolving the residue in ammonia, a solution of ammonium molybdate is obtained. This salt, freed from copper by treatment in ammoniacal solution with ammonium sulphide, and from aluminium by the addition of potassium carbonate, on ignition yields molybdenum dioxide alternatively, heating with excess of sulphur yields pure molybdenum disulphide, MoS, which on roasting, or by treatment with nitric acid, is converted into the trioxide MoOj. ... 

The carbonates, sulphates, and borates are decomposed. The sulphides of the alkalies and alkaline earths are decomposed while the sulphides of arsenic, antimony, molybdenum, zinc, cadmium, tin, iron, lead, copper, mercury, and palladium are not attacked. Cobalt sulphate is not attacked, while the sulphates of the alkalies and alkaline earths are attacked and dissolved. Alkali tungstates, ammonium arsenite and arsenate, copper arsenite, ammonium magnesium arsenate, ammonium molybdate and vanadate, potassium cyanide and ferrocyanide are decomposed. Paraffin is not attacked shellac, gum arabic, gum tragacanth, copal, etc., are decomposed. Celluloid is slowly attacked. Silk paper, gun cotton, gelatin, parchment are dissolved. M. Meslans 22 has studied the esterification of alcohol by hydrofluoric acid. 

In general, molybdenum and its compounds are considered to be of low toxicity to humans however, molybdenum dust and fumes can cause irritation of the eyes, nose, throat, and respiratory tract. The trioxide and ammonium molybdate are more toxic than the ore molybdenite, the metal or the dioxide. It is not irritating to the skin, and is not a sensitizer. Mild cases of molybdenosis may be clinically identifiable only by biochemical changes (e.g., increases in uric acid levels due to the role of molybdenum in the enzyme xanthine oxidase). Excessive intake of molybdenum causes a physiological copper deficiency, and conversely, in cases of inadequate dietary intake of copper, molybdenum toxicity may occur at lower exposure levels. 

The chronic form of Wilson s disease is treated by oral chelating agents, such as penicillamine and trientine, that remove excess copper from tissue and increase urine copper excretion. Oral administration of zinc salts or ammonium molybdate, which block copper intestinal absorption, has also been successful. ... 

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