Patent GB-768238-A (GB)
Title: Simultaneous metal ion concentration and ph control in chemical and biological media
IPC: B01J19/00
Filed: 1953-11-25
Abstract: Predetermined metal ion and hydrogen ion concentrations are controlled simultaneously in a medium having a pH value in the range approximately 5 to 10, by adding to such medium a composition consisting essentially of two different alkali metal salts of a single chelating agent together with a metal complex of such chelating agent, the molar ratios of the two salts and the metal complex in such composition being in the range 1 : 1 : 4 to 1 : 4 : 1 to 4 : 1 : 1, the metal of such complex being that whose concentration is to be maintained in said medium and said chelating agent having the following general formula <FORM:0768238/IV(b)/1> where X is -CH2COOH or -CH2.CH2.COOH; A is -CH2COOH, -CH2.CH2.COOH, hydrogen, alkyl, hydroxy-alkyl, aralkyl, sulfhydryl (-CH2.SH), or an alkyl, hydroxy-alkyl, aralkyl or sulfhydryl group carrying a functional substituent which effects the ionization of the chelating agent without destroying its chelating power; B is -CH2COOH, -CH2.CH2COOH, hydrogen, alkyl, hydroxyalkyl, aralkyl, sulfhydryl, or an alkyl, hydroxyalkyl, aralkyl or sulfhydryl group carrying a functional substituent which effects the ionization of the chelating agent without destroying its chelating power; and alkylene is -CH2.CH2-, -CH(CH3) CH2- or -CH2.CH2.CH2-. Specified functional substituent groups are hydroxyl, carboxyl, ester phosphonic or sulphonic acid.  The medium necessarily contains water and is preferably an aqueous solution or suspension, but the water may be present in small quantities, e.g. in distillery mashes, agar gels and soils.  Specified media are (a) aqueous chemical reaction solutions or suspensions; (b) nutrient media for the growth of micro-organisms in the production of antibiotics, e.g. penicillin, vitamins and yeast; (c) hydroponic solutions for cultivating plants; and (d) aqueous solutions of iron for applying to soil or spraying plants for the treatment of iron chlorosis in plants.  The examples are confined to aqueous solutions containing the compositions of the invention with complexes of various polyvalent metals and illustrate the control of pH and metal ion concentration when a portion of the said metal is removed from solution.  Metals which can be "buffered" are magnesium, calcium, strontium, barium, manganese, ferrous iron, ferric iron, cobaltous cobalt, nickel, copper, zinc, cadmium, lead, rare earths, and transuranic metals.  The alkali metals which are used to form the alkali metal salts of the chelating agent are sodium, potassium, lithium, rubidium and caesium.  Specified chelating agents are (a) ethylene diamine tetra-acetic acid, the salts being the di-and tri-alkali metal salts; (b) dihydroxyethylethylene diamine diacetic acid, the salts being the mono- and di-alkali metal salts; (c) monobutyl ethylene diamine triacetic acid, the salts being the mono- and di-alkali metal salts; (d) monobenzyl ethylene diamine triacetic acid, the salts being the mono- and di-alkali metal salts; (e) ethylene diamine-N,N1-diacetic acid, the salts being the mono- and di-alkali metal salts; (f) diethyl ethylene diamine-N,N1-diacetic acid, the salts being the mono- and di-alkali metal salts; (g) ethylene diamine diacetic-N,N1-dipropionic acid, the salts being the mono- and di-alkali metal salts; (h) ethylene diamine-N,N1-dipropionic acid, the salts being the mono- and di-alkali metal salts; (i) monobutyl ethylene diamine-N,N1-dipropionic acid, the salts being the mono- and di-alkali metal salts; (j) ethylene diamine tetrapropionic acid, the salts being the mono- and di-alkali metal salts; (k) trimethylene diamine tetra-acetic acid, the salts being the mono- and di-alkali metal salts; and (l) propylene diamine tetra-acetic acid, the salts being the mono- and di-alkali metal salts.ALSO:Predetermined metal ion and hydrogen ion concentrations are controlled simultaneously in a medium having a pH value in the range approximately 5 to 10, by adding to such medium a composition consisting essentially of two different alkali metal salts of a single chelating agent together with a metal complex of such chelating agent, the molar ratios of the two salts and the metal complex in such composition being in the range 1:1:4 to 1:4:1 to 4:1:1 the metal of such complex being that whose concentration is to be maintained in said medium and said chelating agent having the following general formula <FORM:0768238/III/1> Where X is -CH2 COCH or -CH2 . CH3 . COOH.  A is -CH2 COOH, -CH2 . CH3 . COOH, hydrogen, alkyl, hydroxy-alkyl, aralkyl, sulphydryl -CH2 . SH, or an alkyl, hydroxy-alkyl, aralkyl or sulfhydryl group carrying a functional substituent which affects the ionization of the chelating agent without destroying its chelating power; B is -CH2 COOH, -CH2 . CH2 COOH, hydrogen, alkyl, hydroxy-alkyl, aralkyl, sulfhydryl, or an alkyl, hydroxyalkyl, aralkyl or sulfhydryl group carrying a functional substituent which effects the ionization of the chelating agent without destroying its chelating power; and alkylene is -CH2 . CH3-, -CH(CH3)CH2- or CH2 . CH2 . CH2-. Specified functional substituent groups are hydroxyl, carboxyl, ester, phosphonic or sulphonic acid.  The medium necessarily contains water and is preferably an aqueous solution or suspension, but the water may be present in small quantities, e.g. in distillery mashes, agar gels and soils.  Specified media are (a) aqueous chemical reaction solutions or suspensions (b) nutrient media for the growth of micro-organisms in the production of antibiotics e.g. penicillin, vitamins and yeast (c) hydroponic solutions for cultivating plants, and (d) aqueous solutions of iron for applying to soil or spraying plants for the treatment of iron chlorosis in plants.  The examples are confined to aqueous solutions containing the compositions of the invention with complexes of various polyvalent metals and illustrate the control of pH and metal ion concentration when a portion of the said metal is removed from solution.  Metals which can be "buffered" are magnesium, calcium, strontium, barium, manganese, ferrous iron, ferric iron, cobaltous cobalt, nickel, copper, zinc, cadmium, lead, rare earths, and transuranic metals.  The alkali metals which are used to form the alkali metal salts of the chelating agent are sodium, potassium, lithium, rubidium and caesium. Specified chelating agents are (a) ethylene diamine tetraacetic acid, the salts being the di- and tri-alkali metal salts (b) dihydroxyethyl-ethylene diamine diacetic acid, the salts being the mono- and dialkali metal salts (c) monobutyl ethylene diamine triacetic acid, the salts being the mono- and di-alkali metal salts, (d) monobenzyl ethylene diamine triacetic acid, the salts being the mono and di-alkali metal salts (e) ethylene diamine -N, N1-diacetic acid, the salts being the mono- and di-alkali metal salts (f) diethyl ethylene diamine -N, N1-diacetic acid, the salts being the mono- and di-alkali metal salts (g) ethylene diamine diacetic -N, N1-dipropionic acid, the salts being the mono- and di-alkali metal salts (h) ethylene diamine-N, N1-dipropionic acid, the salts being the mono and di-alkali metal salts (i) monobutyl-ethylene diamine N, N1-dipropionic acid, the salts being the mono- and di-alkali metal salts (j) ethylene diamine tetraproprionic acid, the salts being the mono- and di-alkali metal salts (k) trimethylene diamine tetraacetic acid, the salts being the mono- and di-alkali metal salts, and (1) propylene diamine tetraacetic acid, the salts being the mono- and di-alkali metal salts.ALSO:Predetermined metal ion and hydrogen ion concentrations are controlled simultaneously in a medium having a pH value in the range approximately 5 to 10, by adding to such medium a composition consisting essentially of two different alkali metal salts of a single chelating agent together with a metal complex of such chelating agent, the molar ratios of the two salts and the metal complex in such composition being in the range 1 : 1 : 4 to 1 : 4 : 1 to 4 : 1 : 1 the metal of such complex being that whose concentration is to be maintained in said medium and said chelating agent having the following general formula:  <FORM:0768238/I/1> Where X is -CH2 COOH or -CH2.CH2.COOH A is -CH2 COOH, -CH2.CH2.COOH, hydrogen, alkly, hydroxyalkyl, aralkyl, sulfhydryl -CH2.SH, or an alkyl, hydroxyalkyl, aralkyl or sulfhydryl groups carrying a functional substituent which affects the ionization of the chelating agent without destroying its chelating power; B is -CH2 COOH, -CH2 COOH, hydrogen, alkyl, hydroxyalkyl, aralkyl, sulfhydryl, or an alkyl, hydroxyalkyl, aralkyl or sulfhydryl groups carrying a functional substituent which effects the ionization of the chelating agent without destroying its chelating power; and alkylene is -CH2.  CH2-, -CH(CH3)CH3- or -CH2.CH2.CH2. Specified functional substituent groups are hydroxyl, carboxyl, ester phosphonic or sulphonic acid.  The medium necessarily contains water and is preferably an aqueous solution or suspension, but the water may be present in small quantities e.g. in distillery meshes, agar gels and soils.  Specified media are (a) aqueous chemical reaction solutions or suspensions, (b) nutrient media for the growth of microorganisms in the production of antibiotics e.g. penicillin, vitamins and yeast (c) hydroponic solutions for cultivating plants, and (d) aqueous solutions of iron for applying to soil or spraying plants for the treatment of iron chlorosis in plants.  The examples are confined to aqueous solutions containing the compositions of the invention with complexes of various polyvalent metals and illustrate the control of pH and metal ion concentration when a portion of the said metal is removed from solution.  Metals which can be "buffered" are magnesium, calcium, strontium, barium, manganese, ferrous iron, ferric iron, cobaltous cobalt, nickel, copper, zinc, cadmium, lead, rare earths, and transuranic metals.  The alka