Ammonia sulfide salts, removal

Makeup washwater for hydrotreater effluent recycle wash-water to remove ammonia sulfide salts that plug downstream condensers and heat exchangers... 

The solution is evaporated to dryness under reduced pressure on a water bath. In order to remove as much hydrochloric acid as possible, the temperature of the bath is raised to 100° toward the end of the distillation. The residue of amino acid hydrochloride and inorganic salts is suspended in 500 cc. of absolute ethyl alcohol. The suspension is boiled on a steam bath for a short time, then cooled to room temperature and filtered on a Buchner funnel. The residue of inorganic salts is washed with 500 cc. of absolute ethyl alcohol. To the combined filtrates is added 400 cc. of ethyl ether (u. s. p. quality) in order to precipitate inorganic material. After several hours the mixture is filtered, and the residue is washed with a 5 2 mixture of absolute ethyl alcohol and ether. The filtrate is transferred to a 5-1. round-bottomed flask, about 200 cc. of water is added, and the liquids are removed by distillation under reduced pressure. The nearly dry residue is dissolved in 2 1. of water, and the solution is treated with an excess of freshly prepared lead hydroxide (Note 5). The suspension is diluted with water to a volume of about 3.5 1. and is then concentrated under reduced pressure, at as low a temperature as possible, to a volume of about 2 1. The suspension is then filtered with suction (Note 6), and the residue of lead salts is washed thoroughly with water. The cloudy filtrate, which still contains some free ammonia, is concentrated by distillation under reduced pressure to a volume of about 300-400 cc. The mixture is filtered, the filtrate is saturated with hydrogen sulfide gas, and the precipitate of lead sulfide is removed by filtration with suction (Note 6). The solution is now concentrated by distillation under reduced pressure on a water bath, and 1 1. of 95 per cent ethyl alcohol is added to the nearly dry residue of the amino acid. The suspension is boiled under a reflux condenser until nearly all the amino acid is dissolved, and the mixture is then allowed to cool to room temperature. The amino acid, which separates in the form of fine needles, is collected on a Buchner funnel and washed with a little 95 per cent ethyl alcohol. A second crop of... 

Gluud A process for removing hydrogen sulfide from gas streams by scrubbing with an aqueous solution containing ammonia and a nickel salt. Invented by W. Gluud in 1921. 

The thiocyanurates are readily hydrolyzed in acid to cyanuric acid and a thiol. Trimethyl trithiocyanurate reacts with sodium sulfide to give the trisodium salts. Melamine is formed on treatment of the thiocyanurates with aqueous ammonia at high temperatures the alkylthio groups are replaced sequentially <59HC(l3)l,p.lll), and can be removed using Raney nickel (equation 25) . 

Alanine has been prepared by the catalytic reduction of cyanoacetic esters 1 or salts 2 by heating acrylonitrile,3 /3-amino-propionitrile,4 iw-(/3-cyanoethyl)-amine,5 /3-hydroxypropionitrile, /3-alkoxypropionitriles,7 u.s-(/3-cyanocthyl) ether,8 or bis-(fi-cyano-ethyl) sulfide 8 with aqueous ammonia at 150-225° by the hydrolysis of /3-aminopropionitrile with concentrated hydrochloric acid and subsequent removal of the acid with anion exchange resins.9 The method as described above has been published.10 Additional references to methods of preparation are given in connection with a procedure for the making of /3-alanine from suc-cinimide through the action of potassium hypobromite.11... 

Hemilian341 used ammonium sulfite on heating ethyl iodide (20 g) with a solution of crystalline ammonium sulfite (20 g) in water (40 ml) he obtained, after cooling, ammonium ethanesulfonate. To convert this into the barium salt he diluted it with water and heated it with lead oxide until evolution of ammonia ceased he filtered the mixture and removed the lead from the filtrate by hydrogen sulfide after renewed filtration he digested the filtrate with barium carbonate, filtered again, and evaporated that filtrate to dryness. 

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