Ammonium carbonate thiocyanate

Another method of preparation consists in heating carbon disulphide with ammonium carbonate in a sealed tube. The other product of this reaction is ammonium thiocyanate. The yield of thiocarbamide by this method is stated to be much below the theoretical value.6... 

The carbamate is a major component of commercial ammonium carbonate. The dithiocarbamate, an intermediate in the preparation oi ammonium thiocyanate (Chap. 19), results from addition of ammonia to one of the double bonds of carbon bisulfide ... 

Yellowish, odorless powder darkens on exposure to light, d 6.47 mp 432. Soly in water (25 ) 0.135 mg/I Insol in alcohol, or most acids. Slightly sol in dil ammonia, but moderately sol in coned ammonia. One liter of 10% ammonia dissolves 3.3 g at 12° sol in solns of alkali cyanides, sparingly sol in solns of thiocyanates Or thiosulfates sol in 220 parts saturated NaCl, in 35 parts saturated KBr solns slightly sol in ammonium carbonate soln. Protect from light. 

Light yellow, odorless powder slowly darkened by light. Crystals are hexagonal Or cubic, d 5.67 mp 552. Practically insol in water (0.03 mg/l) in acid (except coned HI in which it dissolves readily on heating) in ammonium carbonate. Freely sol in solns of alkali cyanides or iedides 35 mg dissolve in a liter of 10% ammouia appreciably sol in coned solns of alkali bromides, chlorides, thiocyanates, thiosulfates, mercuric and silver nitrates. It is slowly attacked by boiling coned acids, but not affected by hot solns of alkali hydroxides. 

Carbon dioxide (CO2) 11.2 Nitrogen (N2) 4.2 Carbon monoxide (CO) 1.1 Water vapor (HjO) 1.1 Hydrogen sulfide (H2S) 0.1 Methane (CH4 0.1 Hydrogen (Hj) 34.1 Potassium carbonate (KjCOj) 8.4 Potassium suifate (K2SO4) 8.1 Potassium suifide (KjS) 4.9 Suifur(S) 0.2 Potassium nitrate (KNOj) 0.1 Potassium thiocyanate (KSCN) 0.1 Ammonium carbonate ((NH4)2CO ) 0.1 Carbon (C)... 

ALUMINUM ALUM ALUMINUM CHLORIDE ALUMINUM FLUORIDE ALUMINUM HYDROXIDE ALUMINUM OXYCHLORIDE ALUMINUM NITRATE ALUMINUM SULFATE AMMONIA (GAS-DRY) AMMONIUM ACETATE AMMONIUM ALUM AMMONIUM BIFLUORIDE AMMONIUM CARBONATE AMMONIUM CHLORIDE AMMONIUM HYDROXIDE AMMONIUM HYDROXIDE, 10% AMMONIUM HYDROXIDE, 28% AMMONIUM METAPHOSPHATE AMMONIUM NITRATE AMMONIUM PERSULFATE AMMONIUM PHOSPHATE AMMONIUM SULFATE AMMONIUM SULFIDE AMMONIUM THIOCYANATE ANTHRAOUINONESULFONIC ACID... 

Alkylaryl Sultonates Allyl Chloride Alum (AmmoniaI Alum iChiomei Alum (PotashI Aluminum Chloride Aluminum Sulfate Ammonium Bicarbonate Ammonium Carbonate Ammonium Chloride Ammonium Nitrate Ammonium Phosphate Ammonium Sulfate Ammonium Thiocyanate Arsenic Trichloride Baking Soda Barium Carbonale Barium Chloride Barium Sultale Barium Sulfide Boian... 

Aminoethanol 2-Aminoisobutyric Acid Ammonia Ammonia Solution Ammonium Ammonium Acetate Ammonium Alum Ammonium Bicarbonate Ammonium Bichromate Ammonium Bifluoride Ammonium Bromide Ammonium Carbonate Ammonium Chloride Ammonium Dichromate Ammonium Fluoride Ammonium Glycolate Ammonium Hydrogen Carbonate Ammonium Hydrogen Fluoride Ammonium Hydrosulfide Ammonium Hydroxide Ammonium Hyposulfite Ammonium Iron Sulfate Ammonium Molybdate Ammonium m-Phosphate Ammonium Nitrate Ammonium o-Phosphate Ammonium Oxalate Ammonium Peroxydisulfate Ammonium Persulfate Ammonium Phosphate Ammonium Phosphate Dibasic Ammonium Rhodanide Ammonium Sulfamate Ammonium Sulfate Ammonium Sulfide Ammonium Thiocyanate Ammonium Thioglycolate Ammonium Thiosulfate... 

Pheiiyl iso-thiocyanate may be prepared in quantity directly from aniline. Aniline, carbon disulphide and concentrated aqueous ammonia react to form the sparingly soluble ammonium phenyldithiocarbamate this is decomposed by lead nitrate to produce phenyl iso-thiocyanate ... 

Chemical Properties. Ammonium thiocyanate rearranges upon heating to an equiHbrium mixture with thiourea 30.3 wt % thiourea at 150°C, 25.3 wt % thiourea at 180°C (373,375). At 190—200°C, dry ammonium thiocyanate decomposes to hydrogen sulfide, ammonia, and carbon disulfide, leaving guanidine thiocyanate [56960-89-5] as a residue. Aqueous solutions of ammonium thiocyanate are weakly acidic a 5 wt % solution has a pH of 4—6. 

Manufacture. An extensive technology was developed initially ia the 1930s for isolation of ammonium thiocyanate from coke-oven gases, but this technology is no longer practiced ia the United States (372). However, such thiocyanate recovery processes are used iadustrially ia Europe. Likewise, the direct sulfurization of cyanides to thiocyanates is not practiced commercially ia the United States. The principal route used ia the United States is the reaction of carbon disulfide with aqueous ammonia, which proceeds by way of ammonium dithiocarbamate [513-74-6]. Upon heatiag, the ammonium dithiocarbamate decomposes to ammonium thiocyanate and hydrogen sulfide. 

This reaction can also be mn in a continuous fashion. In the initial reactor, agitation is needed until the carbon disulfide Hquid phase reacts fully. The solution can then be vented to a tower where ammonia and hydrogen sulfide are stripped countercurrendy by a flow of steam from boiling ammonium thiocyanate solution. Ammonium sulfide solution is made as a by-product. The stripped ammonium thiocyanate solution is normally boiled to a strength of 55—60 wt %, and much of it is sold at this concentration. The balance is concentrated and cooled to produce crystals, which are removed by centrifiigation. 

Cadmium Hydroxide. Cd(OH)2 [21041-95-2] is best prepared by addition of cadmium nitrate solution to a boiling solution of sodium or potassium hydroxide. The crystals adopt the layered stmcture of Cdl2 there is contact between hydroxide ions of adjacent layers. Cd(OH)2 can be dehydrated to the oxide by gende heating to 200°C it absorbs CO2 from the air forming the basic carbonate. It is soluble ia dilute acids and solutions of ammonium ions, ferric chloride, alkah haUdes, cyanides, and thiocyanates forming complex ions. 

Carbon disulfide reacts with concentrated ammonia to give ammonium thiocyanate [1762-95-4] and ammonium trithiocarbonate [13453-08-2] in a reaction promoted by alumina catalysts ... 

The 6-methyl derivative (98, R = Me) was an important intermediate in the synthesis of analogs (e.g., 183) of folic acid. Korte has shown that 2-aminopyrido[3,2-guanidine carbonate with 3-aminopicolinic acid and that treatment of the same acid with ammonium thiocyanate or potassium cyanate yields the thioureido and ureido derivatives (100, X = S and X = 0). In contrast to the pyrido[2,3-d]pyrimidine system bsoth of these compounds could be cyclized by heat and the latter (100, X = O) is a likely intermediate in the synthesis of the dione (98) by the fusion with urea. 

Carbon disulfide is also used to produce xanthates ROC(S)SNa as an ore flotation agent and ammonium thiocyanate as a corrosion inhibitor in ammonia handling systems. 

Successive treatment of 2-(bromomethyl)benzoyl bromide with ammonium thiocyanate and a secondary amine gives the acylthioureas 2, which cyclize in the presence of sodium carbonate to the 3-(disubstituted amino)benzothiazepinones 3.47... 

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