Calcium molybdate

Paris green, see Copper acetate arsenate(III) (1/3) Pawellite, see Calcium molybdate(VI)(2—)... 

The search for new, effective anticorrosive pigments with low toxicity to replace red lead and chromates in paints has occupied the attention of many paint-making companies recently. Barium metaborate, calcium molybdate and zinc molybdate have been identified as possible compounds but they have not found general acceptance in the United Kingdom and western Europe, most probably because of their lower cost effectiveness. 

Calcium Molybdic oxide-molybdate carbon briquettes... 

Calcium, in oil, 27 317 Calcium carbonate, decomposition of, dislocations and, 19 377-389 Calcium molybdate, 27 206... 

Mumallah, N.A.A. and Popiel, W.J. Calcium-selective electrode measurements of calcium molybdate solubilities in water, Anal Chem., 46(13) 2055-2056, 1974. 

More soluble and more active molybdenum compounds, including calcium molybdate and molybdenum trioxide, were fatal at oral daily doses of over 100mg/day. ... 

Molybdenum can also be recovered economically from some uranium leach liquors, particularly those of the USA. When uranium is stripped from amine extractants by solutions of sodium chloride, any molybdenum present remains in the organic phase, and can be subsequently recovered by being stripped into a solution of sodium carbonate. A process has been operated in which the strip liquor is acidified to a pH value of 4.5 and the molybdenum is reextracted into a solution of quaternary amine chloride in kerosene.218 The extracted metal is stripped into a solution containing sodium hydroxide and sodium chloride to produce liquors containing 30-40 g of molybdenum per litre, from which calcium molybdate can be precipitated by the addition of calcium chloride. 

Molybdenum salts used as catalysts include cobalt molybdate for hydrogen treatment of petroleum stocks for desulfurization, and phospho-molybdates to promote oxidation. Compounds used for dyes are sodium, potassium, and ammonium molybdates. With basic dyes, phosphomolyb-dic acid is employed. The pigment known as molybdenum orange is a mixed crystal of lead chromate and lead molybdate. Sodium molybdate, or molybdic oxide, is added to fertilizers as a beneficial trace element. Zinc and calcium molybdate serve as inhibitory pigments in protective coatings arid paint for metals subjected to a corrosive atmosphere. Compounds used to produce better adherence of enamels are molybdenum trioxide and ammonium, sodium, calcium, barium, and lead molybdates. 

SYNS CALCIUM MOLYBDENUM OXIDE (CaMo04) MOLYBDATE, CALCIUM MOLYBDIC ACID (H2M0O4), CALCIUM SALT (1 1)... 

Calcium Molybdate, CaMo04, occurs Yvith the tungstate in the mineral powellite (see p. 111). The normal salt is formed as a white precipitate when calcium chloride is added to a hot concentrated solution of sodium molybdate. - It may also be obtained, in a manner similar to that used for the barium salt, as white microscopic crystals, tetragonal bipyramidal, with a c==l 1-5457. 

The proposed method to process these wastes [11, 13], shown schematically in Fig. 1, consists of leaching them with hot water (1), filtrating (2), treating with mineral acid to pH 3-5 (released nitrous oxides are fixed in the absorption tower), alkalization with ammonia water to pH 7-8 (4), precipitation with the soluble calcium salt to calcium molybdate (5) filtration and washing (6) of the precipitate (7) which can be processed (8) to other molybdenum compounds (9). 

A variety of metal sulfides and their mixtures have been employed to improve the friction stability, wear, and noise characteristics of friction materials. Commonly used sulfides are antimony trisulfide, molybdenum disulfide, tin sulfides, zinc sulfide, copper sulfides, titanium sulfide, and bismuth trisulfide. Sulfide lubricants are usually used to complement carbonaceous lubricants. Fluoride and molybdate additives are sometimes used to enhance the action of carbonaceous and sulfide lubricants. Examples of fluorides are calcium fluoride and cryolite. Sodium and calcium molybdates have been used in small amounts. 

I. From molybdenite, the extraction may be made in several ways, (a) The mineral is roasted as long as sulfur dioxide is given off. The residue which contains MoOs is leached with dilute ammonia and the solution evaporated until the ammonium molybdate crystallizes. Japanese patent 37420 (1920) extracts the roasted ore with Na2COj solution, then precipitates calcium molybdate by adding CaCb. (6) The finely ground ore is heated with nitric acid and the MoOj dissolved in ammonia, (c) A current of chlorine is passed over the dry pulverized ore at a temperature of 208°. The molybdenum chloride distills over and may be separated from sulfur and other chlorides by fractional condensation.2 (d) A British patent describes the extraction with an alkaline sulfide or polysulfide solution which removes the molybdenum from the ore as the soluble thio-molybdates. These may be converted to the molybdates by acidification or by contact with more ore. 

US patent 5,763,630 claims silver catalysts supported on other alkaline earth metal compounds than carbonates, such as calcium titanate, tribasic calcium phosphate, calcium molybdate, or calcium fluoride, as well as the magnesium and strontium analogues. Such supports provide significantly higher selectivity to the desired epoxide than would be expected from the performance of related materials. Selectivities are lower than those reported in the original Union Carbide patent. 

AOM. [Climax Performance] Calcium molybdate flame retardants for plastics. 

Calcium molybdate Calcium molybdate(Vl) Calcium molybdenum oxide (CaMo04) EINECS 232-192-9 Molybdate (Mo042-), calcium (1 1) Molybdate, calcium Molybdic xid (H2M0O4), calcium salt (1 1). Alloying agent in production of iron and steel, crystals in optical and eixtronic applications, phosphors. Soiid d = 4.360 insoluble in H2O, alcohols, soluble in concentrated mineral xids. AAA Molybdenum Atomergic Chemetals Cerac Noah Chem. 

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