Synthesis of new anionic surfactants and their use as collectors in froth flotation of non-sulphidic ores
View Patent ↗The present invention relates to a compound obtainable by reacting an N-acyl neutral amino acid or a salt thereof, or an N-acyl neutral amino acid oligopeptide or a salt thereof with a monohydroxy monocarboxylic acid or a salt thereof. This compound is useful as a collector in a process for froth flotation of non-sulfidic ores, especially phosphate ores. The invention also relates to a method which comprises the steps of a) conditioning a pulped phosphate ore, wherein the phosphate ore comprises a calcium phosphate mineral or a mixture of such minerals, and gangue minerals, with an effective amount of a calcium phosphate mineral collector reagent, which is the above-mentioned compound, and optionally other flotation aids and b) performing a froth flotation process to recover the calcium phosphate mineral(s).
1. A compound obtainable by reacting an N-acyl neutral amino acid or a salt thereof, or an N-acyl neutral amino acid oligopeptide or a salt thereof with a monohydroxy monocarboxylic acid or a salt thereof, wherein the N-acyl group is a group R—(C═O)— where R is a hydrocarbyl group having from 7 to 23 carbon atoms, optionally substituted.
2. A compound according to claim 1 , where the neutral amino acid is selected from the group consisting of glycine, alanine, sarcosine, valine, leucine and isoleucine.
3. A compound according to claim 1 , where the monohydroxy monocarboxylic acid is selected from the group consisting of lactic acid and glycolic acid.
4. A compound according to claim 1 having the structural formula
where R is a hydrocarbyl group having from 7 to 23 carbon atoms, optionally substituted; R 1 is H or CH 3 ; R 2 is H or a C1-C4 alkyl group; R 3 is H or CH 3 ; n is a number 1-20; p is a number 1-3; X is H + or a cation which is organic or inorganic, and m represents the valency of the cation and is a number 1-2.
5. A composition comprising:
a) a compound according to claim 1 ,
b) an N-acyl neutral amino acid or a salt thereof, and
c) a fatty acid RCOOH, where R is a hydrocarbyl group having from 7 to 23 carbon atoms, optionally substituted, or a salt thereof.
6. A composition according to claim 5 wherein a) is present in an amount of 1-20 mol %, b) is present in an amount of 30-60 mol % and c) is present in an amount of 40-60 mol %, wherein the amounts are calculated based on the total molar amount of a), b) and c).
7. A method for froth flotation of non-sulfidic ores, the method comprising:
a) conditioning a pulped phosphate ore, wherein the phosphate ore comprises a calcium phosphate mineral or a mixture of such minerals, and gangue minerals, with an effective amount of a calcium phosphate mineral collector reagent, which is a compound as defined in claim 1 , and optionally other flotation aids and
b) performing a froth flotation process to recover the calcium phosphate mineral(s).
8. A pulp comprising phosphate ore, a compound according to claim 1 , and optionally a depressant.
9. A compound obtainable by reacting an N-acyl neutral amino acid or a salt thereof, or an N-acyl neutral amino acid oligopeptide or a salt thereof with a monohydroxy monocarboxylic acid or a salt thereof, wherein the compound has the structural formula
where R is a hydrocarbyl group having from 7 to 23 carbon atoms, optionally substituted; R 1 is H or CH 3 ; R 2 is H or a C1-C4 alkyl group; R 3 is H or CH 3 ; n is a number 1-20; p is a number 1-3; X is H + or a cation which is organic or inorganic, and m represents the valency of the cation and is a number 1-2.
10. A compound according to claim 9 , where the neutral amino acid is selected from the group consisting of glycine, alanine, sarcosine, valine, leucine and isoleucine.
11. A compound according to claim 9 , where the monohydroxy monocarboxylic acid is selected from the group consisting of lactic acid and glycolic acid.
12. A composition comprising:
a) a compound according to claim 9 ,
b) an N-acyl neutral amino acid or a salt thereof, and
c) a fatty acid RCOOH, where R is a hydrocarbyl group having from 7 to 23 carbon atoms, optionally substituted, or a salt thereof.
13. A composition according to claim 12 wherein a) is present in an amount of 1-20 mol %, b) is present in an amount of 30-60 mol % and c) is present in an amount of 40-60 mol %, wherein the amounts are calculated based on the total molar amount of a), b) and c).
14. A method for froth flotation of non-sulfidic ores, the method comprising:
a) conditioning a pulped phosphate ore, wherein the phosphate ore comprises a calcium phosphate mineral or a mixture of such minerals, and gangue minerals, with an effective amount of a calcium phosphate mineral collector reagent, which is a compound as defined in claim 9 , and optionally other flotation aids and
b) performing a froth flotation process to recover the calcium phosphate mineral(s).