Zinc-calcium molybdates

Coatings, Paints, and Pigments. Various slightly soluble molybdates, such as those of zinc, calcium, and strontium, provide long-term corrosion control as undercoatings on ferrous metals (90—92). The mechanism of action presumably involves the slow release of molybdate ion, which forms an insoluble ferric molybdate protective layer. This layer is insoluble in neutral or basic solution. A primary impetus for the use of molybdenum, generally in place of chromium, is the lower toxicity of the molybdenum compound. 

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. 

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. 

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. 

Chem. Descrip. Calcium molybdate CAS 7789-82-4 EINECS/ELINCS 232-192-9 Uses Conosion inhibitor pigment for optimal package stability in resin systems destabilized by zinc compds. fungistat Eeatures Nonbasic chromate and lead-free Properties Wh. 

Stronbum zinc molybdate phosphoslllcate pigment, corrosion inhibiting wash primers Moly-White 92 pigment, corrosion inhibitor Calcium molybdate... 

See Calcium-zinc-molybdenum complex /Wo/y-Wh/fe 331. See Zinc molybdate Moiy-Whit 501. See Calcium molybdate Moiy-Whit Zinc Phosphate. See Zinc phosphate... 

C18 acid triglyceride lumber treatment Zinc chloride luminescent materials Calcium molybdate... 

Cadmium iodide Calcium fluoride Calcium molybdate Calcium sulfide Cerium oxide Copper oxide (ic) Germanium cis-Stilbene trans-Stilbene Zinc phosphate phosphors, color TV tubes Yttrium oxide phosphors, lamp... 

Moiybdates. Calcium molybdates and zinc molybdates and various modifications thereof (15) are commercially available from Sherwin Williams as KEMGARDS, and are principally used in PVC as smoke suppressants (15). 

A calcium molybdate compound for polymers destabilized by zinc at elevated processing temperatures. 

H. 8-Hydroxyquinaldine (XI). The reactions of 8-hydroxyquinaldine are, in general, similar to 8-hydroxyquinoline described under (C) above, but unlike the latter it does not produce an insoluble complex with aluminium. In acetic acid-acetate solution precipitates are formed with bismuth, cadmium, copper, iron(II) and iron(III), chromium, manganese, nickel, silver, zinc, titanium (Ti02 + ), molybdate, tungstate, and vanadate. The same ions are precipitated in ammoniacal solution with the exception of molybdate, tungstate, and vanadate, but with the addition of lead, calcium, strontium, and magnesium aluminium is not precipitated, but tartrate must be added to prevent the separation of aluminium hydroxide. 

Bis(benzene)chromium dichromate, 3851 Calcium chromate, 3926 Copper chromate oxide, 4223 Dibismuth dichromium nonaoxide, 0232 Lead chromate, 4243 Lithium chromate, 4236 Magnesium permanganate, 4691 Potassium dichromate, 4248 Potassium permanganate, 4647 Sodium dichromate, 4250 Sodium molybdate, 4713 Sodium permanganate, 4703 Zinc permanganate, 4710... 

Property Zinc molybdate pigment Calcium zinc molybdate pigment Basic sodium zinc molybdate pigment Basic calcium zinc phosphomolybdate pigment... 

Quantitative risk assessments have been performed on a variety of flame-retardants used both in upholstered furniture fabric and foam. The National Research Council performed a quantitative risk assessment on 16 chemicals (or chemical classes) identified by the U.S. Consumer Product Safety Commission (CPSC). The results were published in 2000.88 The 16 flame-retardants included in this NRC study were HBCD, deca-BDE, alumina trihydrate, magnesium hydroxide, zinc borate, calcium and zinc molybdates, antimony trioxide, antimony pentoxide and sodium antimonate, ammonium polyphosphates, phosphonic acid, (3- [hydroxymethyl]amino -3-oxopropyl)-dimethylester, organic phosphonates, tris (monochloropropyl) phosphate, tris (l,3-dichloropropyl-2) phosphate, aromatic phosphate plasticisers, tetrakis (hydroxymethyl) hydronium salts, and chlorinated paraffins. The conclusions of the assessment was that the following flame-retardants can be used on residential furniture with minimal risk, even under worst-case assumptions ... 

The use of the pure molybdate-based pigments available on the market is limited due to their cost [5.53, 5.56]. To overcome this disadvantage, molybdate, and phosphate pigments are combined (see Section 5.2.5.2.) or molybdate compounds are apphed to inorganic fillers like calcium carbonate and/or zinc oxide [5.56, 5.91]. 

The ability of zinc ions to block copper absorption, possibly by formation of- intestinal metallothionein that strongly binds copper, has led to its use in pharmacological doses in the management of Wilson s disease/ Similarly molybdate ion can form insoluble copper-molybdate complexes in the intestine that limit copper absorption. The detrimental effects of organic phosphate (phytic acid) in limiting zinc absorption are aggravated by excess dietary calcium, probably by formation of a highly insoluble Ca-Zn-phytate complex. The subject of these and other interactions has been reviewed, ... 

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