Sulphamates

Solutions of ammonium carbamate NH4SO3NH2 have no action on aluminium, even at 125 °C. 

Cold ammonium sulphamate solutions NH4SO3NH2 do not attack aluminium. Hot sulphamate decomposes, releasing sulphuric acid that renders these solutions aggressive towards aluminium. 

Hydrocarbons are the main constituents of crude oil and natural gas. They are the largest class of compounds in organic chemistry, to which fuels, polymers etc. belong, and are very important in today s chemical industry. 

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Both compounds are soluble in water and are readily hydrolysed to sulphamic acid, HjN S03" andammonia the hydrogen atoms are in each case replaceable by metals to form salts. Many derivatives of sulphamide and cyclic derivatives of sulphimide are known. 

The sulphuric acid may be replaced by 1-2 g. of sulphamic acid (NH,SOjH) or by p-toluenesulphonic acid (p-CHjCjH SOjH). 

In the second method of homogeneous precipitation, the precipitant itself is generated by a chemical reaction. For example, Ba + can be homogeneously precipitated as BaS04 by hydrolyzing sulphamic acid to produce S04 . 

In order to obtain a sufficient rate of cure at moulding temperatures it is usual to add about 0.2-2.0% of a hardener (accelerator). This functions by decomposing at moulding temperatures to give an acidic body that will accelerate the cure rate. A very large number of such latent acid catalysts have been described in the literature, of which some of the more prominent are ammonium sulphamate, ammonium phenoxyacetate, ethylene sulphite and trimethyl phosphate. 

Nitrohydrochloric acid Perchloric acid Phenosulphonic acid Phosphorus pentoxide Propionic acid Selenic acid Spent acids Sulphamic acid Sulphuric acid and oleum (fuming sulphuric acid) Sulphurous acid Thioglycolic acid Trichloroacetic acid... 

Ammonium sulphamate Amorphous silica /1-Amyl acetate... 

Ammonium chloride - fume Ammonium sulphamate (ammate) n-Amyl acetate sec-Amyl acetate Aniline... 

Numerous new salts and additive compounds of cinchona alkaloids, and especially of quinine, have been described, of which only a few can be mentioned as examples quinine additive compounds with sulph-anilamide, t quinine salts of (+) and (—)-pantothenic acid, °( > quinine sulphamate and disulphamate, °( organo-mercury compounds of quinine and cinchonine such as quinine-monomercuric chloride. Various salts and combinations of quinine have also been protected by patent, e.g., ascorbates and nicotinates. 

Sulfur and Sulfur Compounds, 123 Sulfur chloride, 123 Sulfur dioxide, 123 Sulfur hexafluoride, 123 Sulfur tetrafluoride, 124 Sulfur trioxide, 124 Sulfuric acid, 123 Sulfurous acid, 124 Sulfuryl fluoride, 124 Sulphamic acid, 124 Sulprofos, 124... 

Other electroplating solutions Other solutions, which are more rarely used for plating copper, include the fluoborate bath, the amine bath, the sulphamate bath and the alkane sulphonate bath. 

Deposits from Watts-type solutions Most coatings of nickel for engineering applications are electro deposited from a Watts-type bath Typical mechanical properties of deposits from Watts and sulphamate solutions are compared with those of wrought nickel in Table 13.15. 

A comprehensive and authoritative study of the sulphamate bath has been made by Hammond. ... 

Deposits from other solutions Nickel can be deposited from solutions based on salts other than the sulphate, chloride and sulphamate. Solutions based on nickel fluoborate, pyrophosphate, citrate, etc. have been extensively studied but none of them is used to any significant extent in Europe for engineering deposits. 

Wearmouth has described the production of nickel-cobalt, nickel-manganese, and nickel-chromium alloy coatings for non-decorative uses. The nickel-cobalt and nickel-manganese are electrodeposited direct from sulphamate-based solutions, the nickel-cobalt alloys offering higher hardness than the nickel-manganese alloys, which are restricted to a relatively... 

For ruthenium, electrolytes based on ruthenium sulphamate or nitrosyl-sulphamate have been described, but the most useful solutions currently available are based on the anionic complex (H2 0 Cl4 Ru N Ru-Cl4-OH2) . The latter solutions operate with relatively high cathode efficiency to furnish bright deposits up to a thickness of about 0-005 0 mm, which are similar in physical characteristics to electrodeposited rhodium and have shown promise in applications for which the latter more costly metal is commonly employed. Particularly interesting is the potential application of ruthenium as an alternative to gold or rhodium plating on the contact members of sealed-reed relay switches. 

Iridium has been deposited from chloride-sulphamate and from bromide electrolytes , but coating characteristics have not been fully evaluated. The bromide electrolytes were further developed by Tyrrell for the deposition of a range of binary and some ternary alloys of the platinum metals, but, other than the platinum-iridium system, no commercial exploitation of these processes has yet been made. 

Heat exchanger surfaces need to he kept clean. Aqueous circuits (evaporator or condenser) can he cleaned with a chemical such as sulphamic acid, brushed or subjected to high-pressure water jets. In each case, all traces of dirt and chemical need to be removed from the circuit before it is put back to work. In cases of doubt, the manufacturer s advice should be sought. A layer of scale 2 mm thick on a condenser tube can cause a power increase of 16%, and the need to clean a condenser can usually be deduced from the condensing pressure. Persons using high-pressure water jets should wear face masks to avoid inhaling aerosol droplets. 

Sulphates. Sulphate ion may be generated by the hydrolysis of aminosulphonic (sulphamic) acid ... 

The barium sulphate may be precipitated either by the use of sulphuric acid, or from homogeneous solution by the use of sulphamic acid solution which produces sulphate ions on boiling ... 

Procedure Precipitation from homogeneous solution (sulphamic acid method). The... 

No satisfactory direct gravimetric procedure is available but nitrite can be oxidised to nitrate by permanganate or cerium(IV) and then determined in that form. The determination of total nitrate + nitrite is an important analysis, e.g. for soil samples. Nitrite may be destroyed using urea, sulphamic acid or hydrazine sulphate the reaction with the former is ... 

A review of earlier results is included in a paper by Kiyoura and Urano [946] on the decompositions of (NH4)2S04 (413—513 K) and NH4HS04 (433-473 K). The intermediate formation at 433 K of the double salt (NH4)3H(S04)2 was detected by X-ray diffraction and this salt decomposed to NH4HS04 at 453 K. Decomposition of the ammonium hydrogen sulphate at 473 K proceeded through the formation of molten sulphamic acid... 

Ammonium chloride fume Ammonium perfluorooctanoate Ammonium sulphamate Amosite, see Asbestos n-Amyl acetate sec-Amyi acetate Aniline and homologues " Anisidine (o>. p-isomers)... 

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