Salt recovery solution and processes of use thereof
The present invention relates to a salt recovery solution and to a process for separating a salt from an aqueous solution. The present disclosure also relates to a salt recovery solution and to its use to concentrate a salt or brine solution by recovering water therefrom. The salt recovery solution comprising at least two or more components independently selected from any combination of integers a), b), c) and d): where a) is a straight, branched or optionally substituted cyclic C 4 -C 9 ether containing compound; b) is a straight chain or branched C 3 -C 9 alkyl substituted by —OH; c) is a straight chain, branched or cyclic C 4 -C 9 ketone or C 4 -C 9 diketone; and d) is a straight chain or branched C 3 -C 9 ester containing compound.
1 . A process for recovering an inorganic salt from a salt containing aqueous solution containing inorganic salts, the process comprising the steps of:
(i) adding the salt containing aqueous solution containing inorganic salts to a salt recovery solution; and
(ii) allowing the inorganic salt to precipitate on passage through the salt recovery solution,
wherein the salt recovery solution comprises at least two or more components independently selected from any combination of integers a), b), c) and d), wherein
a) is a straight, branched or optionally substituted cyclic C 4 -C 9 ether containing compound;
b) is a straight chain or branched C 3 -C 9 alkyl substituted by —OH;
c) is a straight chain, branched or cyclic C 4 -C 9 ketone; and
d) is a straight chain or branched C 3 -C 9 ester containing compound; and
wherein at least one component of the salt recovery solution is substantially immiscible with an aqueous solution of sodium chloride at a 1 molar concentration at or above 20 degrees Celsius and at 1 atmosphere.
2 . The process as claimed in claim 1 , wherein the process is
a) a zero-liquid discharge process;
b) a counter current process; or
c) is a non-membrane process.
3 . A process for concentrating a salt containing aqueous solution containing inorganic salts, the process comprising the steps of:
(i) adding the salt containing aqueous solution containing the inorganic salts to a salt recovery solution, wherein the salt recovery solution comprises at least two or more components independently selected from any combination of integers a), b), c) and d): wherein
a) is a straight, branched or optionally substituted cyclic C 4 -C 9 ether containing compound;
b) is a straight chain or branched C 3 -C 9 alkyl substituted by —OH;
c) is a straight chain, branched or cyclic C 4 -C 9 ketone or C 4 -C 9 diketone; and
d) is a straight chain or branched C 3 -C 9 ester containing compound; and
wherein at least one component of the salt recovery solution is substantially immiscible with an aqueous solution of sodium chloride at a 1 molar concentration at or above 20 degrees Celsius and at 1 atmosphere; and
(ii) allowing water from the salt containing aqueous solution containing the inorganic salts to pass into the salt recovery solution.
4 . The process as claimed in claim 3 , wherein the process is:
i) a non-membrane process;
ii) a non-osmotic process; or
iii) a non-membrane and non-osmotic process.
5 . The process as claimed in claim 3 , wherein the process concentrates the salt containing aqueous solution containing the inorganic salts by a value selected from:
a) at least 20%;
b) by at least 30%;
c) by at least 40%;
d) by at least 50%;
e) by at least 60%;
f) by at least 70%;
g) by at least 80%; and
h) by at least 90%.
6 . The process as claimed in claim 3 , wherein the process is a minimal discharge process or a zero-liquid discharge process.
7 . The process as claimed in claim 3 , wherein the salt containing aqueous solution is an industrial brine.
8 . The process as claimed in claim 3 , wherein the straight, branched or optionally substituted cyclic C 4 -C 9 ether containing compound is selected from one or more of a diether, a polyether, 2-methyltetrahydrofuran, 3-methyltetrahydrofuran, 2-ethyltetrahydrofuran, 3-ethyltetrahydrofuran, dioxane, 1-ethoxypropane, a C 4 -C 9 glycol ether, propylene glycol methyl ether, dipropylene glycol methyl ethyl acetate, dipropylene glycol n-propyl ether, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, tripropylene glycol n-butyl ether, propylene glycol phenyl ether, propylene glycol diacetate, and combinations thereof.
9 . The process as claimed in claim 3 , wherein the straight chain or branched C 3 -C 9 alkyl substituted by —OH is selected from one or more of: 1-butanol, 2-butanol, 1-pentanol, and combinations thereof.
10 . The process as claimed in claim 1 , wherein the straight chain, branched or cyclic C 4 -C 9 ketone or C 4 -C 9 diketone is selected from one or more of: acetonylacetone, 2-butanone, and cyclohexanone.
11 . The process as claimed in claim 3 , wherein the straight chain or branched C 3 -C 9 ester containing compound is methyl acetate or ethyl acetate.
12 . The process as claimed in claim 1 , wherein the straight, branched or optionally substituted cyclic C 4 -C 9 ether containing compound is a diether or polyether.
13 . The process as claimed in claim 1 , wherein the straight, branched or optionally substituted cyclic C 4 -C 9 ether containing compound is selected from one or more of: 2-methyltetrahydrofuran, 3-methyltetrahydrofuran, 2-ethyltetrahydrofuran, 3-ethyltetrahydrofuran, dioxane, 1-ethoxypropane, a C 4 -C 9 glycol ether, propylene glycol methyl ether, dipropylene glycol methyl ethyl acetate, dipropylene glycol n-propyl ether, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, tripropylene glycol n-butyl ether, propylene glycol phenyl ether, propylene glycol diacetate, and combinations thereof.
14 . The process as claimed in claim 1 , wherein the straight chain or branched C 3 -C 9 alkyl substituted by —OH is selected from one or more of: 1-butanol, 2-butanol, 1-pentanol, and combinations thereof.
15 . The process as claimed in claim 1 , wherein the straight chain, branched or cyclic C 4 -C 9 ketone is selected from one or more of: 2-butanone and cyclohexanone.
16 . The process as claimed in claim 1 , wherein the straight chain or branched C 3 -C 9 ester containing compound is methyl acetate or ethyl acetate.
17 . The process as claimed in claim 1 , wherein the salt recovery solution is a combination of:
a) 2-methyltetrahydrofuran and 1-butanol;
b) 2-methyltetrahydrofuran and 1-pentanol;
c) ethyl acetate and 2-butanone;
d) ethyl acetate and 2-methyltetrahydrofuran; or
e) ethyl acetate and 1-butanol.
18 . The process as claimed in claim 1 , wherein the salt containing aqueous solution is an industrial brine.