Patent GB-461001-A (GB)
Title: Improvements in the removal of organically combined sulphur from gases
IPC: C10K1/18
Filed: 1935-07-02
Abstract: Specified salts of organic amino acids are prepared as follows: the potassium salt of g  - hydroxyethylamino - a  - diethylene - triaminobutyric acid by acetylating g -aminobutyric acid, brominating the resulting product, converting the brominated product with diethylenetriamine, saponifying the acetyl group and converting the resulting product with ethylene oxide; the sodium salt of a -propylenediamino-e -amino caproic acid by acetylating e -amino caproic acid, brominating the product, converting it with propylene diamine and saponifying the acetyl group; the potassium-sodium salt of a , a <1>, (triethylene-tetramino)-dipropionic acid by reacting triethylenetetramine with two molecular proportions of acetaldehyde and of hydrocyanic acid and saponifying the resulting nitrile by means of a mixture of caustic soda and caustic potash; the potassium-sod3um-monoethanolamine salt of triethylenetetramino-a -propionic acid diacetic acid by converting triethylenetetramine with one molecular proportion of acetaldehyde and of hydrocyanic acid, reacting the resulting product with two molecular proportions of formaldehyde and of hydrocyanic acid and saponifying the resulting product by means of equimolecular proportions of caustic potash, caustic soda and monoethanolamine; the sodium salt of a -diethylenetriamino-propionic acid from diethylenetriamine, acetaldehyde and hydrocyanic acid and the saponification of the resulting product; the potassium salt of diethylenetriamino-acetic acid from diethylenetriamine, formaldehyde and hydrocyanic acid and the saponification of the resulting product; the sodium salt of triethylenetetramino-succinic acid by reacting a -bromo succinic acid with triethylenetetramine; the barium salt of ethylenediamino - acetic acid by reacting ethylenediamine with formaldehyde and hydrocyanic acid, and saponifying the resulting nitrile by means of baryta; the sodium-calcium salt of tetraethylenepentamino-citric acid by reacting tetraethylenepentamine with monobromo-citric acid; the sodium-potassium salt of ethylenediamino-malic acid by reacting ethylenediamine with bromo-malic acid; the sodium salt of triethylenetetramino-diacetic acid by reacting triethylenetetramine with two molecular proportions of formaldehyde and of hydrocyanic acid and saponifying the resulting nitrile; the sodium salt of diethylenetriamino-diacetic acid by reacting diethylenetriamine with three molecular proportions of formaldehyde and of hydrocyanic acid and saponifying the resulting nitrile; the sodium salt of ethyl-ethylenediamino-diacetic acid by reacting ethyl-ethylenediamine with two molecular proportions of formaldehyde and of hydrocyanic acid and saponifying the resulting nitrile; the sodium salt of triethylenetetramino-acetic acid by reacting triethylenetetramine with one molecular proportion of formaldehyde and of hydrocyanic acid and saponifying the resulting nitrile or by reacting triethylenetetramine with chloracetic acid; the potassium salt of p-diethylenetriamino-benzoic acid from diethylenetriamine and pchlorbenzoic acid; the sodium salt of 3-(diethylenetriamino)-anthracene-2-carboxylic acid by reacting 3-chloranthracene-2-carboxylic acid and diethylenetriamine; the benzylamine salt of ethylene-diamino-acenaphthene carboxylic acid by reacting chlor-acenaphthene carboxylic acid and ethylene diamine and neutralizing the product with benzylamine; the ethylenediamine salt of triethylenetetramino - anthranilic acid by acetylating anthranilic acid, chlorinating it and converting the chlorination product with triethylenetetramine, saponifying the acetyl group and neutralizing the product with ethylenediamine; diethylenetriamino - terephthalic acid which constitutes an intramolecular salt by reacting diethylenetriamine and chlorterephthalic acid; the sodium salt of diethylene-triamino-cyclopentane carboxylic acid from chlor-cyclopentane carboxylic acid and diethylenetriamine; and an intramolecular salt by reacting chlor-cumalic acid with hydroxyethyldiethylenetriamine.ALSO:Organically combined sulphur (e.g. carbon disulphide or carbon oxysulphide) is removed from gases by bringing the gas, preferably in the presence of moisture, into contact with strong organic bases or basic-reacting salts of strong inorganic or organic bases at such high temperatures that the organically combined sulphur is converted into hydrogen sulphide which is lead away from the purifying agent together from the gas and that no substantial absorption of weak gaseous acids by the purifying agent takes place.  Temperatures of 90--200 DEG  C. are suitable. The hydrogen sulphide may be subsequently removed in any suitable manner.  If the basic compounds are liquid they may be employed as such or in the form of solutions.  Solutions in water and/or non-hydrating solvents may be employed.  Suitable solvents are high boiling hydrocarbons, washing oils, tar oils, oils from low temperature carbonization, cracking or hydrogenation processes, petroleum fractions and tetra-hydronaphthalene.  Oxygen containing solvents such as ethers, ketones and alcohols may also be employed. The boiling point and/or the wetting power of the solution may be increased by means of additions such as paraffin wax, inorganic salts or surface tension-reducing agents such as alkylated aromatic sulphonic acids.  Such additions may yield true solutions, emulsions or suspensions.  For example, a suspension of calcium chloride in amyl alcohol may be employed as a solvent. Two or more non-miscible solvents may be employed.  The basic compounds may also be distributed on solid supports, e.g. lumps of coke.  The process may be carried out at any desired pressure but preferably at the prevailing gas pressure.  The organic bases which may be employed include tetramethyl-ammonium hydroxide, monoethanolamine, diethanolamine, triethanolamine, butyldiethanolamine, dimethylethanolamine, diaminoisopropanol, ethylenediamine, and bases having the formula <FORM:0461001/III/1> (in which B is an aliphatic hydrocarbon radicle which may contain a simple or substituted amino group and in which at least one of the groups A is an alkyl or aryl group which may contain a hydroxyl group or a simple or substituted amino group, or in which two of the groups A attached to different nitrogen atoms constitute an alkylene group while the remaining groups A are hydrogen, alkyl or aryl groups).  Bases of this last class include dihydroxyethylethylene diamine, monohydroxymethyl - ethylene triamine, monomethylmonohydroxyethylethylenetetramine, monohydroxyethylethylene diamine and methylhydroxyethyl-ethylene diamine.  The alkaline-reacting salts of inorganic bases which may be employed include potassium phosphate, potassium metaborate, sodium tetraborate, potassium carbonate, the sodium or potassium salts of alanine or of glycocoll, the potassium salt of methylalanine, the sodium salt of dimethylalanine and the potassium salt of dihydroxyethylglycocoll.  The salts of strong inorganic or organic bases which may be used include those of amino-acids corresponding to one of the following formulae <FORM:0461001/III/2> (in which, G1 and G3 are hydrogen or hydrocarbon groups which may contain a hydroxy or a simple or substituted amino group or a carboxylic group or more than one of these groups, G2, D and E are hydrocarbon groups which may also contain a hydroxy or a simple or substituted amino group or a carboxylic group or one or more of these groups, G4 is hydrogen or an aliphatic hydrocarbon group which may also contain a hydroxy or a simple or substituted amino group or a carboxylic group or more than one of these groups, and in which ring closures may take place between the groups in any desired manner). Examples of such salts are, the potassium salt of g -hydroxyethylamino - a  - diethylene - triaminobutyric acid obtainable by acetylating g -aminobutyric acid, brominating the resulting product, converting the brominated product with diethylenetriamine, saponifying the acetyl group and converting the resulting product with ethylene oxide; the sodium salt of a -propylene-diamino-e -amino caproic acid obtainable by acetylating e -amino caproic acid, brominating the product, converting it with propylene diamine and saponifying the acetyl group; the potassium-sodium salt of a , a <1>-(triethylenetetramino)-dipropionic acid obtainable by reacting triethylenetetramine with two molecular proportions of acetaldehyde and of hydrocyanic acid and saponifying the resulting nitrile by means of a mixture of caustic soda and caustic potash; the potassium-sodium-monoethanolamine salt of triethylenetetramino-a -propionic acid diacetic acid obtainable by converting triethylenetetramine with one molecular proportion of acetaldehyde and of hydrocyanic acid, reacting the resulting product with two molecular proportions of formaldehyde and of hydrocyanic acid and saponifying the resulting product by means of equimolecular proportions of caustic potash, caustic soda and monoethanolamine; the sodium salt of a -diethylenetriamino-propionic acid obtainable from diethylenetriamine, acetaldehyde and hydrocyanic acid and the saponification of the resulting product; the potassium salt of diethylenetriamino-acetic acid obtainable from diethylenetriamine, formaldehyde and hydrocyanic acid and the saponification of the resulting product; the sodium salt of triethylenetetramino-succinic acid obtainable by reacting a -bromo succinic acid with triethylenetetramine; the barium salt of ethylenediamino-acetic acid obtainable by reacting ethylenediamine with formaldehyde and hydrocyanic acid, and saponifying the resulting nitrile by means of baryta; the sodium-calcium salt of tetraethylene-pentamino-citric acid obtainable by reacting tetraethylene pentamine with monobromo-citric acid; the sodium-potassium salt of ethylenediamino-malic acid obtainable by reacting ethylenediamine with bromo-malic acid;