Acid copper chromate

Acid copper chromate, composition and specifications for, 6 558t Acid copper plating, 9 807-811 preparing solution for, 9 808 Acid coupling, 9 358-359... 

Water-borne preservatives are divided into two categories. One group which includes acid copper chromate, chromated zinc chloride, copperized chromated zinc arsenate and fluorchrome-arsenate-phenol is used where the wood is not subjected to excessive leaching. The second group, ammoniacal copper arseuite and three types of chromated copper arsenate which react to become practically water insoluble, are used at about 0.6 lb/ft3 (9.6 kg/m3) when wood is placed in ground contact under severe service conditions. 

The timber used in this type of cooling tower is commonly pressure-treated redwood, Douglas fir, and other wood species, the preservative being chromated copper arsenate or, more usually today, acid copper chromate. Despite the wood preservative, it is not uncommon to find wood decay and biological fouling of the plenum area and drift eliminators. 

Water-soluble inorganic salts acid copper chromate ammoniacal copper arsenite chromated copper arsenate chromated zinc chloride fluor chrome arsenate phenol... 

CCA = chromated copper arsenate (types A, B, C are different formulations) AC A = ammoniacal copper arsenate ACC = acid copper chromate CFA = chromated fluorarsenate ACF = ammoniacal copper fluoride CZC = chromated zinc chloride, copperized CKB = (chromated copper borate CC = copper chromate NaPCP = sodium pentachlorophenol PCP = pentachlorophenol and Creo = creosote. 

Acid Copper Chromate (ACC). This preservative is formulated by mixing copper sulfate, sodium dichromate, and chromic acid. 

ACC acid copper chromate g subscript denoting green... 

Waterborne Salts. Waterborne salts for wood preservation include zinc chloride, chro-mated zinc chloride, copperized chromated zinc chloride, zinc meta arsenite, chromated zinc arsenate, chromated copper arsenate, ammoniacal copper arsenite, acid copper chromate, and fluor chrome arsenate phenol. These chemicals leave little odor and have little effect on the appearance of the wood, which may also be painted. The zinc chloride salts, at high penetrations, also provide fire retardance.Wood should be reseasoned before use because this type of chemical treatment injects a large amount of water into the wood. 

Key to symbols ACA, ammoniacal copper arsenate ACC, Acid copper chromate CCA, chromated copper arsenate CZC, chromated zinc chloride FCAP, Fluor chrome arsenate phenol NR, not recommended Penta, pentachlorophenol. 

Acid copper chromate Ammoniacal copper arsenite Chromated copper arsenate Chromated zinc chloride Fluor chrome arsenate phenol... 

Lead—copper alloys are also used as tank linings, tubes for acid mist precipitators, steam heating pipes for sulfuric acid or chromate plating baths, and flashing and sheeting (see Tanks AND pressure vessels). 

Chromia—alumina catalysts are prepared by impregnating T-alumina shapes with a solution of chromic acid, ammonium dichromate, or chromic nitrate, followed by gentie calciaation. Ziac and copper chromites are prepared by coprecipitation and ignition, or by thermal decomposition of ziac or copper chromates, or organic amine complexes thereof. Many catalysts have spiael-like stmctures (239—242). 

List of abbreviations BOD, biological oxygen demand CA, chloroanisol CCA, copper-chromate-arsenate CP, chlorophenol 2,4-D, dichlorophenoxyacetic acid DCP, dichlorophenol CFSTR, continuous-flow stirred tank reactor FBBR, fluidized-bed biofilm reactor MCP, monochlorophenol NAPL, non-aqueous phase liquid PAH, polycyclic aromatic hydrocarbon PCPP, polychlorinated phenoxyphenol PCDF, polychlorinated dibenzofuran PCDD, polychlorinated dibenzodioxin PCR, polymerase chain reaction PCP, pentachlorophenol PCA, pentachloroanisole TeCP, tetrachlorophenol TeCA, tetrachloroanisole TCC, trichlorocatechol TCP, trichlorophenol TOC, total organic carbon 2,4,5-T, trichlorophenoxyacetic acid UASB, upflow anaerobic sludge blanket reactor VSS, volatile suspended solids. 

EDTA can be a useful additive to an acid copper bath since it can offer some control over dissolution of the anode. In high-efficiency cyanide copper plating, the addition of EDTA can counter the harmful effects of chromate(VI). It is speculated that the chelating agent facilitates the reduction of CrVI to Crm by Cu1. 

Oxidants. Hydrogen sulfide ignites on contact with silver bromate,8 bromine pentafluoride,9 mercury(I) bromate,10 lead hypochlorite,11 copper chromate,12 fluorine,13 fuming nitric acid,14 solid sodium peroxide,15 and dry or moist lead oxide.5 16 Dichlorine oxide17 or chlorine trifluoride18 explodes on contact with hydrogen sulfide. Heated chromium trioxide incandesces in a stream of hydrogen sulfide. 

Perhaps the most extensive area of research in simple pretreatment systems to enhance the weathering properties of wood has involved application of inorganic salt solutions. Much of the early work in this field was undertaken at the U.S. Forest Products Laboratory in Madison, Wisconsin and was aimed at improving the performance of transparent finishes. Black [25] described an experimental chromate-based wood finish and Black and Mraz [26] discovered that both acid and ammoniacal-copper chromate treatments significantly improved the performance of clear finishes on western red cedar, redwood (Sequoia sempervirens), and Douglas fir plywood. Later research [27] demon-... 

Ignites on contact with metal oxides (e.g., barium peroxide, chromium trioxide, copper oxide, lead dioxide, manganese dioxide, nickel oxide, silver(I) oxide, silver(II) oxide, sodium peroxide, thallium(III) oxide, mercury oxide, calcium oxide, nickel oxide), oxidants (e.g., silver bromate, heptasilver nitrate octaoxide, dibismuth dichromium nonaoxide, mercury(I) bromate, lead(II) hypochlorite, copper chromate, fluorine, nitric acid, sodium peroxide, lead(IV) oxide), rust, soda-lime + air. Reacts violently with NI3, NF3, p-bromobenzenediazonium chloride, OF2, F2, Cu, CIO, BrFs,... 

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