Zinc molybdate phosphate

Ziuc hydroxymolybdate-phosphate or basic zinc molybdate-phosphate [38,39]... 

Offline passivation involves treatment of equipment currently out of service. Treatment levels are typically higher consequently, passivation is completed more quickly. Passivation of nonchromate treatment generally uses either a polyphosphate, zinc, molybdate or other nonchromate-based inhibitor in combination with various surface-active cleaning agents. The passivation solution should be disposed of after the pretreatment stage, rather than dumped back into the cooling system where the potential for fouling can exist due to the precipitation of pretreatment compounds such as zinc or phosphate. Table 8.1 outlines both online and offline pretreatment procedures. 

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 ... 

Characteristic Unit Caicium zinc moiybdate Caicium zinc phosphate moiybdate Zinc molybdate Zinc phosphate molybdate... 

Chem. Descrip. Basic calcium zinc molybdate-based Uses Corrosion inhibitor for protective coatings Eeatures Economical stable synergistic with zinc phosphate Properties Wh. fine powd. < 0.1% 325 mesh residue 3.2 p mean particle size nodular shape sp.gr. 3.0 oil absorp. 17 g/100 g < 0.5% moisture... 

Synonyms Zinc phosphomolybdate Definition Zinc phosphate modified with zinc molybdate Uses Corrosion-inhibiting pigment for coatings Trade Names Heucophos ZMP Moly-White ZNP Moly-White ZNPED-Plus... 

Molybdenum tungsten hydroxide oxide phosphate, compd. with ethyl 2-(6-ethylamino)-3-(ethylimino)-2,7-dimethyl-3H-xanthen-9-yl) benzoate. See Pigment red 81 Molybdenum white. See Calcium-zinc-molybdenum complex Zinc molybdate Molybdic acid, ammonium salt, tetrahydrate. 

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... 

Melamine phosphate Molybdenum trioxide Paraffin, chlorinated Pentabromodiphenyl oxide Pentaerythritol Perchloropentacyclodecane Tetrabromobisphenol A bis (allyl ether) Tributoxyethyl phosphate Tributyl phosphate Trichloroethylene Tris (chloropropyl) phosphate Tris (2,3-dibromopropyl) phosphate Zinc borate Zinc molybdate Zinc phosphate flame retardant, plastics, flame retardant, elastomers Zinc sulfide... 

Triaryl phosphate Trixylenyl phosphate Zinc molybdate flame retardant, PVC foam Tris (2,3-dichloropropyl) phosphate flame retardant, PVC wire/cable insulation Trixylenyl phosphate flame retardant, radio/TV parts Hexabromobiphenyl flame retardant, reactive... 

Tetrabromobisphenol A bis (allyl ether) Tri (P,P -dichloroisopropyl) phosphate flame retardant, unsaturated polyesters Zinc molybdate flame retardant, upholstery Ammonium octamolybdate flame retardant, urethane foams Pentabromodiphenyl oxide flame retardant, vinyl Resorcinol bis (diphenylphosphate) flame retardant, vinyl film Diphenyl octyl phosphate flame retardant, vinyl foam t-Butylphenyl diphenyl phosphate flame retardant, vinyl nitrile foam t-Butylphenyl diphenyl phosphate flame retardant, vinyl resins Trioctyl phosphate flame retardant, vinyl sheeting Diphenyl octyl phosphate flame retardant, wall coverings Ammonium octamolybdate flame retardant, wall coverings high risk buildings... 

Inorganic inhibitors incorporated into coatings include borate, chromate, molybdate, phosphate, phosphite, or silicate, typically as anticorrosive pigments (salts) of the metals aluminum, barium, calcium, strontium, or zinc. It should be noted that many of the inorganic inhibitors are anions and are, therefore, candidates for incorporation as dopant anions into CP coatings for controlled release. 

Phosphate pre-treatments may be either zinc phosphate (from zinc dihydrogen phosphate solutions) or an iron phosphate (fi om alkali phosphate solutions) (see Conversion coating and Pre-treatment of steel). The conversion reactions are promoted by accelerators (depolarizers), for example, bromates or molybdates in alkali phosphate baths or chlorates in zinc phosphate baths (with Ca or Ni grain-refining additions). Iron phosphate pre-treatment coatings are often described as amorphous . In practice, however, they are usually crystalline deposits of iron oxides and iron phosphate. Zinc phosphate pre-treatment coatings are always crystalline. A fine, dense crystal pattern of zinc phosphate on the metal surface is the ideal, as it improves both paint adhesion and corrosion resistance most effectively. 

Typical pigment Zinc phosphate Zinc phosphate Calcium zinc molybdate (CZM) NaV03+ Corrostain (Ca, Zn, P, Si and 0)... 

Basic zinc molybdenum phosphate hydrate. Zinc molybdate is added to basic zinc phosphate hydrate so it can be used with water-soluble systems. 

Beland suggests that corrosion protection comes both from the ability of the tripolyphosphate ion to chelate iron ions (passivating the metal) and from tripolyphosphate ions ability to depolymerize into orthophosphate ions, giving higher phosphate levels than zinc or molybdate phosphate pigments [23]. 

Basic calcium zinc molybdate/zinc phosphate... 

Kemgard product chemistries include zinc molybdate, calcium sine molybdate and zinc oxide/phosphate cosplexes. 

Engineering works elemental fragments, oxide dross metal, primers ZnO, ZnCr04, zinc molybdate, zinc phosphate elemental fragments, oxide dross... 

Features Synergistic with other corrosion inhibitors such as Zinc salts, molybdates, phosphates, and azoles... 

Chemical inhibitors, when added in small amounts, reduce corrosion by affecting cathodic and/or anodic processes. A wide variety of treatments may be used, including soluble hydroxides, chromates, phosphates, silicates, carbonates, zinc salts, molybdates, nitrates, and magnesium salts. The exact amount of inhibitor to be used, once again, depends on system parameters such as temperature, flow, water chemistry, and metal composition. For these reasons, experts in water treatment acknowledge that treatment should be fine tuned for a given system. 

Fluoride, in the absence of interfering anions (including phosphate, molybdate, citrate, and tartrate) and interfering cations (including cadmium, tin, strontium, iron, and particularly zirconium, cobalt, lead, nickel, zinc, copper, and aluminium), may be determined with thorium chloranilate in aqueous 2-methoxyethanol at pH 4.5 the absorbance is measured at 540 nm or, for small concentrations 0-2.0 mg L 1 at 330 nm. 

Molybdenum-based anticorrosive pigments offer a nontoxic alternative to the zinc chromate pigments [5.120], They all have a neutral color (white) but the pure compounds are very expensive. To produce economically competitive pigments molybdate and phosphate pigments are combined, or molybdate compounds are applied to inorganic fillers (e.g., zinc oxide, alkaline-earth carbonates, or talc) [5.75], [5.121]—[5.123]. 

Many of the finishes applied to other types of metal products can also be applied to zinc die castings, although some differences in formulation as well as occasional differences in method of application may be desirable. The types of finishes applicable to zinc die castings include mechanical finishes (buffed, polished, brushed, and tumbled) electrodeposited finishes (copper, nickel, chromium, brass, silver, and black nickel) chemical finishes (chromale, phosphate, molybdate and black nickel) and organic finishes (enamel, lacquer, paint and varnish, and plastic finishes). Electrodeposited coatings of virtually any metal capable of electrodeposition can be applied to zinc die castings. 

Fig. 12.49. Action of corrosion inhibitors, (a) Anodic inhibitors. Examples Chromate, nitrite, molybdate, tungstate, orthophosphate, silicate, benzoate, (b) Cathodic inhibitors. Examples Ca(HC03)2, ZnS04, Cr2(S04)3, NiS04 phosphate, aminoethylene phosphate (AMP), Ag3+, Sb3+ (on iron) Hg (on zinc), (c) Mixed inhibitors. Examples organic inhibitors containing nitrogen and/or sulfur (e.g., amines, triazoles, thiazoles, alkylthioureas) inorganic inhibitors (e.g., arsenite, arsenate, selenate). (Reprinted from G. Ranglen, Corrosion of Metals, p. 165,1985 with permission from Chapman Hall.)...

Inhibitive Primers. The traditional primers are red lead and linseed oil, alkyd resins and zinc potassium chromate, proprietary epoxy, alkyd, urethane and latex systems with modified phosphate, borate and molybdate pigments. Chromate-based pigments, although in use in aircraft coatings, automotive primers and coil coating primers, are subject to environmental concern on the toxicity of hexavalent chromium which is likely to result in their replacement by innocuous products. 

Lead-based inhibitors and zinc phosphate inhibitors are thought to plug up the discontinuities in the natural oxide layer and hence offer protection. This is akin to the repair of an imperfect oxide film of iron by chromates, molybdates or tungstates. 

The mitigation of corrosion can be achieved economically by the use of corrosion inhibitors. Chromate has been extensively used in an aqueous environment for the protection of aluminium, zinc and steel. Although chromates are cheap and effective, they are not acceptable because of their toxicity. Alternate inhibitors such as molybdates, organic inhibitors such as phosphonates, mixtures of phosphates, borates and silicates and surfactants like sulfonates have been used in place of chromates. Chromates are anodic inhibitors and help to form passive oxide on the metal surface. 

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