Alkalis moderate

Alkali moderation of supported precious metal catalysts reduces secondary amine formation and generation of ammonia (18). Ammonia in the reaction medium inhibits Rh, but not Ru precious metal catalyst. More secondary amine results from use of more polar protic solvents, CH OH > C2H5OH > Lithium hydroxide is the most effective alkah promoter (19), reducing secondary amine formation and hydrogenolysis. The general order of catalyst procUvity toward secondary amine formation is Pt > Pd Ru > Rh (20). Rhodium s catalyst support contribution to secondary amine formation decreases ia the order carbon > alumina > barium carbonate > barium sulfate > calcium carbonate. 

Red tetragonal crystals or brown powder density 9.64 g/cm decomposes on heating at 290°C practically insoluble in water also insoluble in alkalis moderately soluble in hydrochloric acid and also, in nitric acid-hydrogen peroxide mixture slowly dissolves in acetic acid. 

Good resistance lo most mineral acids. Dissolves with partial decomposition in concentrated sulfuric acid. Good resistance to weak alkalis, Moderate resistance to strong alkalis ... 

Properties White crystals from ethanol. Mp 84C, bp 320-322C. Soluble in ethanol, ether, chloroform, benzene, acetic acid, caustic alkalies moderate solubility in hot water. Combustible. 

Crystals from boiling ethanol, ethyl acetate or benzene, mp 248-249 (dec). Levorotatory. Sol in boiling acetone and chloroform readily sol in aq alkalies moderately sol in boiling ethanol sparingly sol in benzene. 

Direct production of select MDCHA isomer mixtures has been accompHshed using mthenium dioxide (30), mthenium on alumina (31), alkali-moderated mthenium (32) and rhodium (33). Specific isomer mixtures are commercially available from an improved 5—7 MPa (700—1000 psi) medium pressure process tolerant of ohgomer-containing MDA feeds (34). Dimethylenetti(cyclohexylamine) (8) [25131 -42-4] is a coproduct. 

Features Exc. stability in hard water, alkalis moderately stable in acids Pmperties Pale straw pumpable paste m.w. 379-389 pH 7-9 (1%) 68-72% act. Envimnmental Biodeg. 

Uses Detergent, wetting and foaming agent, emulsifier for liq. deteigents, shampoos, bath prods., wallboard mfg., textiles, drilling aux. exc. stability in hard water, alkalis moderately stable In acids Properties Pale straw pumpable paste m.w. 420-430 sp.gr. 1.05 vise. 40,000 cps pH 7-9 (1%) 68-72% act. 

Antimony forms both a + 3 and a + 5 oxide. The + 3 oxide can be prepared by the direct combination of the elements or by the action of moderately concentrated nitric acid on antimony. It is an amphoteric oxide dissolving in alkalis to give antimonates(III) (for example sodium antimonite , NaSb02), and in some acids to form salts, for example with concentrated hydrochloric acid the trichloride, SbCl3, is formed. 

Nickel is a moderately lustrous, silvery metal, and is extensively used in alloys (for example coinage, stainless steel) and for plating where a durable resistant surface is required. It is also used as an industrial catalyst, for example in the hydrogenation of unsaturated organic compounds. It is attacked by dilute aqueous acids but not by alkalis it combines readily with many non-metals on heating. 

Physical properties. Majority are liquids except p toluidine and 1- and 2-naphthylamine. All are colourless when pure, but rapidly darken on exposure to air and light. All are very sparingly soluble in water, but dissolve readily in dilute mineral acids (except the naphthyl-amines, which are only moderately soluble in adds). They form colourless crystalline salts e.g., CjHjNH2,HCl) which are soluble in water these aqueous solutions usually have an add reaction owing to hydrolysis, and give the reactions of both the amine and the acid from which they are derived. Addition of alkali to the acid solution liberates the amine. 

Physical properties of hexachloroethane are Hsted in Table 11. Hexachloroethane is thermally cracked in the gaseous phase at 400—500°C to give tetrachloroethylene, carbon tetrachloride, and chlorine (140). The thermal decomposition may occur by means of radical-chain mechanism involving -C,C1 -C1, or CCl radicals. The decomposition is inhibited by traces of nitric oxide. Powdered 2inc reacts violentiy with hexachloroethane in alcohoHc solutions to give the metal chloride and tetrachloroethylene aluminum gives a less violent reaction (141). Hexachloroethane is unreactive with aqueous alkali and acid at moderate temperatures. However, when heated with soHd caustic above 200°C or with alcohoHc alkaHs at 100°C, decomposition to oxaHc acid takes place. 

Oxazoles give acylamino ketones (158) by acid-catalyzed ring scission, although they are somewhat more stable than furans. The oxazole ring is also moderately stable to alkali (74AHCU7)99) as expected, reaction with hydroxide ions is facilitated by electron-with-drawing substituents and fused benzene rings. 

Group IIA metals inelude Be, Mg, Ca, Sr, Ba and Ra whieh are grey, moderately-hard, high melting-point substanees. Like the alkali metals they attaek water to liberate hydrogen but with less vigour. The salts of the alkaline earths are generally less stable towards heat and water than those of alkali metals, and less water soluble. 

In addition to the stable I2O5 and moderately stable I4O9 and I2O4, several short-lived radicals have been detected and characterized during y-radiolysis and flash photolysis of iodates in aqueous alkali ... 

On the basis of the dissociation constant values, it seems sensible to conclude that, in these moderately basic carbinolamines, the hydrogen atom of the hydroxyl group is suflQciently acid to be eliminated under the influence of an alkali and by its transfer to the nitrogen atom of the mesomeric anion, the formation of the amino-aldehyde form may result. Instead of the amino-aldehyde, however, the corresponding bimolecular ether (15a-c) can be obtained. " It can be concluded that the formation of the bimolecular ether (S l or 8 2 mechanism) and the formation of the amino-aldehyde (B-SeI or B-Se2 mechanism) are competitive reactions. It seems probable that where the first reaction can occur the latter one is pushed into the background. The triple tautomeric system postulated by Gadamer... 

There is no attack by ammonia, and caustic alkalis can be used in contact with the austenitic types up to moderately high temperatures, but in strong solutions of caustic alkalis at temperatures approaching boiling point some attack will occur. 

Alkalis Molybdenum is moderately resistant to aerated solutions of ammonium hydroxide and is inert when oxygen is excluded. It has only fair resistance in aerated 1 % sodium hydroxide at 35°C and 60°C but its resistance is better in a 10% solution at both these temperatures. It is severely corroded in sodium hypochlorite solutions (pH 11 or higher) at 35°C (Table 5.4). 

Titanium is almost invariably resistant towards neutral salts, particularly halides, at temperatures up to 100°C, and in respect of the latter environments it is significantly more resistant than stainless steel. In strong solutions of caustic alkalis, on the other hand, titanium tends to form soluble titanates, and it is not as resistant as say, nickel. While at low or moderate concentrations of alkali there is no significant attack, the metal has appreciable solubility in concentrated or molten caustic alkali. Titanium is however resistant to attack by aqueous ammonia at all concentrations and temperatures and to anhydrous ammonia . 

There are a Tew compounds of alkalies, nitrate, and acetate thai have low solubilities, but most of them are quite complex in composition. For example, sodium uranyl acetate, NaUQifCHjCOOh has low solubility. Silver acetate is an exception but its solubility is moderate. 

Beryllium Oxide (Bromellite). BeO, mw 25.01, white amorph powd, mp 2530°, bp ca 3900°, d 3.01g/cc. Sol in coned acids and alkalies. V si sol in w. Prepn is by burning BeC03 at 900° in a Pt crucible to the oxide. It is used in nuclear reactor fuels and moderators as well as in powder metallurgy, ceramics, fuel cells and coatings (see above)... 

Foamability of phosphoric acid esters in aqueous solutions is in general only moderate, with the acid phosphates showing a better stability against water hardness than the alkali or amine salts. 

From TPD data obtained at low CO coverages, it is possible to estimate the initial heats of adsorption 45,46 AH 0, of CO on alkali modified surfaces. Figure 2.15 a shows the dependence of AH°0 on alkali coverage, for CO adsorption on alkali modified Ru(1010) It is clear that up to moderate alkali coverages the... 

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