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Alkaline earth salts

Monofluorophosphates. Monofluorophosphates are probably the best characterized series of fluoroxy salts. The PO F ion is stable ia neutral or slightly alkaline solution. The alkaU metal and ammonium monofluorophosphates are soluble ia water but the alkaline-earth salts are only slightly soluble, eg, CaPO F is not water-soluble and precipitates as the dihydrate. [Pg.226]

Alkali or alkaline-earth salts of both complexes are soluble in water (except for Ba2[Fe(CN)g]) but are insoluble in alcohol. The salts of hexakiscyanoferrate(4—) are yellow and those of hexakiscyanoferrate(3—) are mby red. A large variety of complexes arise when one or more cations of the alkah or alkaline-earth salts is replaced by a complex cation, a representative metal, or a transition metal. Many salts have commercial appHcations, although the majority of industrial production of iron cyanide complexes is of iron blues such as Pmssian Blue, used as pigments (see Pigments, inorganic). Many transition-metal salts of [Fe(CN)g] have characteristic colors. Addition of [Fe(CN)g] to an unknown metal salt solution has been used as a quaUtative test for those transition metals. [Pg.434]

Petroleum sulfonates are widely used as solubilizers, dispersants (qv), emulsifiers, and corrosion inhibitors (see Corrosion and corrosion inhibitors). More recentiy, they have emerged as the principal surfactant associated with expanding operations in enhanced oil recovery (66). Alkaline-earth salts of petroleum sulfonates are used in large volumes as additives in lubricating fluids for sludge dispersion, detergency, corrosion inhibition, and micellar solubilization of water. The chemistry and properties of petroleum sulfonates have been described (67,68). Principal U.S. manufacturers include Exxon and Shell, which produce natural petroleum sulfonates, and Pilot, which produces synthetics. [Pg.241]

Carbon or siUcon may produce britdeness and loss of useful properties. Caustic alkalies and many alkaline earth salts or hydroxides may attack platinum at elevated temperatures. [Pg.484]

No attempt should be made to purify perchlorates, except for ammonium, alkali metal and alkaline earth salts which, in water or aqueous alcoholic solutions are insensitive to heat or shock. Note that perchlorates react relatively slowly in aqueous organic solvents, but as the water is removed there is an increased possibility of an explosion. Perchlorates, often used in non-aqueous solvents, are explosive in the presence of even small amounts of organic compounds when heated. Hence stringent care should be taken when purifying perchlorates, and direct flame and infrared lamps should be avoided. Tetra-alkylammonium perchlorates should be dried below 50° under vacuum (and protection). Only very small amounts of such materials should be prepared, and stored, at any one time. [Pg.5]

We encountered the solubilities of alkaline earth salts in Chapter 10 and discovered some interesting trends. Before looking back to Figures 10-5 and 10-6, see how much you can recall about these solubilities. [Pg.382]

Although any given source of water typically has a wide range of dissolved minerals present, and each of these has a potential for causing difficulties to a greater or lesser extent, it is the alkaline earth salts (.hardness salts) that are always present to some degree and generally are the most troublesome in a boiler. This section discusses these salts, their presence in natural makeup (MU) water sources, and their contribution to hardness scales and deposition in boiler plants. [Pg.221]

Deposit control agents (DCAs) or antiscalents to inhibit the deposition of CaC03 and other alkaline earth salts. [Pg.442]

The DKR of amine is more challenging compared to that of secondary alcohol since no metal catalysts have been known for the efficient racemizahon of amine. Reetz et al. reported for the first time the DKR of amine, in which 1-phenylethylamine was resolved by the combination of lipase and palladium (Scheme 4). In this procedure, CALB and Pd/C were employed as the combo catalysts. However, the DKR required a very long reaction time (8 days) at 50-55°C and provided a poor isolated yield (60%). Recently, an improved procedure using Pd on alkaline earth salts as the racemizahon catalyst was reported by Jacobs et al. " The DKR reachons were performed at 70°C for 24-72 h and 75-88% yields were obtained with 99% or greater enanhomeric excess. [Pg.72]

Using this approach, calculations can be made of volumetric, entropic and energy parameters taking account of the effect of overlapping cospheres. Some indication of the organization in the solution is also possible. The properties of a number of concentrated salt solutions have been analysed by this procedure, including simple 1 1 salts, alkaline earth salts and alkylammonium salts. [Pg.45]

The direct determination of cadmium in seawater is particularly difficult because the alkali and alkaline earth salts cannot be fully charred away at temperatures that will not also volatilise cadmium. Most workers in the past [125,132-135] who have attempted a direct method have volatilised the cadmium at temperatures which would leave sea salts in the furnace. This required careful setting of temperatures, and was disturbed by situations that caused temperature settings to change with the life of the furnace tubes. [Pg.147]

Seawater samples usually contain a total of 2 - 3% of several alkali and alkaline earth salts, with sodium chloride as a main constituent. A 2 pi sample of... [Pg.148]

Staples, B. R. "Ionic Equilibrium Constants of Aqueous Alkaline Earth Salts" Environ. Sci. Technol., 1978, 12,... [Pg.487]

Other thermodynamic properties of aqueous solutions are being evaluated. A recent publication reports values calculated for the association constants of aqueous ionic species at 298 K for alkaline earth salts (Staples, 1978). [Pg.541]

Electrowinning Generally this method is limited to La, Ce, Pr and Nd because of their low-melting points. The rare earth salt (fluoride, chloride, etc.) mixed with an alkali or alkaline-earth salt is heated to 700-1100°C and then an electric dc current passed through the cell. If the bath temperature is above the melting point of the R, drops of the molten metal drip off of the cathode and are collected at the bottom of the cell. Generally, the electrowon metal is not as pure as that obtained by metallothermic reduction. [Pg.555]

The alkali metal and alkaline earth salts are soluble, as are many of the salts of other metals. [Pg.208]

The structural aspects and thermal decomposition mechanisms of some alkaline earth salts of NTO have also been reported and their mechanism of decomposition is similar [163, 164]. [Pg.113]

Esters (and certain other compounds) may be susceptible to hydrolysis by low or especially high pH, or in the presence of alkaline metal or alkaline earth salts. In the presence of acid, i.e., anion and hydrogen ion, the reaction is at equilibrium. However, in the presence of base and the associated cations, the reaction is driven to completion (e.g., acetyl salicylic acid and the effect of sodium and magnesium salts on the rate and extent of reaction). [Pg.100]

Acrylonitrile was first produced in Germany and the United States on an industrial scale in the early 1940s. These processes were based on the catalytic dehydration of ethylene cyanohydrin. Ethylene cyanohydrin was produced from ethylene oxide and aqueous hydrocyanic acid at 60°C in the presence of a basic catalyst. The intermediate was then dehydrated in the liquid phase at 200°C in the presence of magnesium carbonate and alkaline or alkaline earth salts of fonnic acid. A second commercial route to acrylonitrile was the catalytic addition of hydrogen cyanide to acetylene. The last commercial plants using these process technologies were shut down in 1970 (Langvardt, 1985 Brazdil, 1991). [Pg.45]

Alkali and Alkaline Earth Salts of Azidodithiacarbonic Acid... [Pg.633]

Although many of the alkali and alkaline earth salts have been prepd, studied and found to be explosive (Refs 1,2 3), only the more important ones are described here... [Pg.634]

In fact, concentrated solutions of sodium chloride are used to precipitate partially neutralized PAA (2). Further, if partially neutralized, even dilute solutions of PAA can be precipitated through addition of alkaline earth salts (3). [Pg.166]

McNutt(Ref 3) used the Pb salt with Ba(NOs)2 as a priming compon miyt, and instead of the Pb salt, he proposed alk alkaline earth salts of azidodinitrobenzene with LA, Ba(NOa)2, Sb2S3,... [Pg.42]


See other pages where Alkaline earth salts is mentioned: [Pg.200]    [Pg.445]    [Pg.488]    [Pg.176]    [Pg.119]    [Pg.1010]    [Pg.445]    [Pg.104]    [Pg.315]    [Pg.436]    [Pg.199]    [Pg.156]    [Pg.326]    [Pg.161]    [Pg.20]    [Pg.128]    [Pg.61]    [Pg.9]    [Pg.445]    [Pg.195]    [Pg.11]   
See also in sourсe #XX -- [ Pg.58 ]

See also in sourсe #XX -- [ Pg.423 ]

See also in sourсe #XX -- [ Pg.58 ]

See also in sourсe #XX -- [ Pg.159 ]




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