Method and system for desalination

Abstract

Methods and systems for desalination of water are described. In an embodiment, a method of desalination includes (a) providing a vessel which includes a cold zone; a hot zone; a working fluid which includes a substantially non-polar alcohol spanning the cold zone and the hot zone; a feed water inlet configured to mix saline water with the working fluid in the cold zone; a reject outlet configured to remove saline water from the working fluid in the cold zone; and a desalinated water outlet configured to remove desalinated water from the working fluid in the hot zone; where the hot zone is configured to be maintained at a substantially warmer temperature than the cold zone; (b) adding saline water to the vessel via the feed water inlet; and (c) removing desalinated water from the vessel via the desalinated water outlet.

Description

METHOD AND SYSTEM FOR DESALINATIONCROSS REFERENCE TO RELATED APPLICATION

[0001] This PCT application claims the benefit of U.S. Provisional Application No. 63 / 603,231, filed November 28, 2023. The entire contents of this application isp hereby incorporated by reference in its entirety.TECHNICAL FIELD

[0002] The present invention relates to a method and system for desalination of water.BACKGROUND

[0003] This section provides background information related to the present disclosure and is not necessarily prior art.

[0004] Fresh water is vital, and in some locations, scarce. Sources of salty water are plentiful but desalination can be energy intensive, particularly for technologies based on evaporation and / or reverse osmosis. Other technologies are in development but are less widely deployed, including capacitive deionization and interfacial solar steam generation.

[0005] Furthermore, some technologies can increase the concentration of undesirable elements in the source water. Boron is an agriculturally important contaminant present in many alkaline wells / water sources. Boron is worse than salt for decreasing crop yields and is harder to rinse out of the soil.

[0006] Accordingly, there remains a need for sustainable methods and systems for water desalination.SUMMARY

[0007] In one aspect, a method of water desalination is described, the method including: (a) providing a vessel which includes: a cold zone; a hot zone; a working fluid including a substantially non-polar alcohol spanning the cold zone and the hot zone; a feed water inlet configured to mix saline water with the working fluid in the cold zone; a reject outlet configured to remove saline water from the working fluid in the cold zone; and a desalinated water outlet configured to remove desalinated water from the working fluid in the hot zone; where the hot zone is configured to be maintained at a substantially warmer temperature than the cold zone; (b) adding saline water to the vessel via the feed water inlet; and (c) removing desalinated water from the vessel via the desalinated water outlet.

[0008] In some embodiments, the hot zone can include a wall of the vessel. In some embodiments, the hot zone can include a hot finger in the vessel.10009 ] In some embodiments, the vessel can further include a desalinated water collector. The desalinated water collector can be positioned below the hot zone and can be connected to the desalinated water outlet. The vessel can further include one or more mixers positioned to mix working fluid and saline water. The vessel can further include one or more baffles. The vessel can further include one or more cooling boxes.

[0010] In some embodiments, the working fluid can include a C4-C25 alcohol. The working fluid can include a C6-C19 (e.g., Ce-Cis) alcohol. The working fluid can include a C7-C15 alcohol having an odd number of carbon atoms. The working fluid can include 1 -pentanol, 2- pentanol, isoamyl alcohol, I -hexanol, 2 -hexanol, 3 -hexanol, 1-heptanol, 1 -octanol, 2-ethyl-l- hexanol, 1-nonanol, 2-nonanol, 1 -decanol, 1-undecanol, or 1-dodecanoL hi some embodiments, the working fluid can include a first substantially non-polar alcohol and a second substantially non-polar alcohol.

[0011] In some embodiments, the concentration of boron in the desalinated water is lower than the concentration of boron in the saline water.

[0012] In another aspect, a system for the desalination of water is described, which includes a vessel which includes: a cold zone; a hot zone: a working fluid including a substantially non- polar alcohol spanning the cold zone and the hot zone: a feed water inlet configured to mix saline water with the working fluid in the cold zone; a reject outlet configured to remove saline waler from the working fluid in the cold zone; and a desalinated waler outlet configured to remove desalinated water from the working fluid in the hot zone; where the hot zone is configured to be maintained at a substantially warmer temperature than the cold zone.

[0013] In some embodiments, the hot zone comprises a wall of the vessel. In some embodiments, the hot zone comprises a hot finger in the vessel.

[0014] In some embodiments, the vessel can further include a desalinated water collector. The desalinated water collector can be positioned below the hot zone and can be connected to the desalinated water outlet. The vessel can further include one or more mixers positioned to mix working fluid and saline water. The vessel can further include one or more baffles. The vessel can further include one or more cooling boxes.

[0015] Other features and advantages will be apparent from the following detailed description, figures, and from the claims.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following figures are provided by way of example and are not intended to limit the scope of the claimed invention.

[0017] FIGS. 1A and IB are schematic drawings of a system for desalination.

[0018] FIG. 2 is a schematic drawing of a system for desalination that employs a hot finger structure.

[0019] FIG. 3 is a schematic drawing of a system for desalination that employs multiple hot finger structures.

[0020] FIG. 4 is a schematic draw’ing of a system for desalination that includes a laminar flow plate and a fluid path for recirculating working fluid.DETAILED DESCRIPTION

[0021] Water desalination technologies include evaporative methods and filtration methods (e.g., reverse osmosis). Another approach to water desalination relies on the ability of certain solvents to selectively absorb water molecules from saline water. The solvents are typically non-polar and have a temperature-dependent water solubility (Choi et al. J. Haz. Mat. 403, 123636). Some classes of solvents considered for this purpose include alcohols, ketones, amines, and organic acids (Gilliland, Indust. & Eng. Chem. 47, 12, 2410-2422, 1955); and amines, fatty' acids, mixtures of alcohols and nitriles, and mixtures of alkyl benzenes and paraffinic compounds (Luo et al., J. Appl. Phys. 110, 054905, 2011).

[0022] The term “working fluid” as used herein refers to a liquid used in the systems and methods described herein for the desalination of water. A working fluid for the systems and methods described herein desirably has limited miscibility’ with water (of any salinity), has greater miscibility with pure w ater than w'ith saline water, and its miscibility' with w'ater is temperature dependent. A working fluid can be a single liquid (e.g., 1 -octanol) or a mixture of liquids (e.g., a mixture of 1-octanol and 1 -nonanol). The term “working fluid” without further elaboration includes both its “dry” state (i.e., where the working fluid is substantially free of water) and its “w’et” state (i.e., where the working fluid has been mixed with w'ater). Additional features and properties of working fluids are discussed below’.

[0023] The terms “non-polar” and “substantially' non-polar” as used herein refer to the polarity of liquids (e.g.. solvents) which may' be used as a working fluid in the systems and methods described herein. As the term is used herein, solvents with a dielectric constant (at, e.g., 20 °C) of 20 or less can be considered “substantially non-polar”. As the term is used herein, solvents with a dielectric constant (at, e.g., 20 °C) of 15 or less can be considered “non-polar”. Accordingly, the term “substantially non-polar” encompasses the term “non- polar”, and “substantially non-polar alcohol” includes “non-polar alcohol”.10024 ] The term “saline water” as used herein refers to water with a relatively high concentration of dissolved salts. The term can include both naturally occurring water (e.g., seawater, river water, lake water, well water, etc.) and water to which salt(s) have been artificially added. For example, seawater can have 30 g / L or more of dissolved salts. As used herein, “saline water” typically refers to water having a concentration of dissolved salts sufficiently high that the water is unsuitable for use in agriculture, drinking, or cooking.

[0025] The term “desalinated water” as used herein refers to water that has been treated by the systems and / or methods described herein to provide water of lower salinity than the saline water that was input to the system and / or method. Thus, as the term “desalinated water” is used herein, does not specify a particular concentration of dissolved salts, but instead refers to water that has been subjected to the desalination systems and / or method(s) described herein.

[0026] It will be understood that embodiments described with reference to a system may be applicable to the methods described herein, and vice versa.

[0027] I. METHOD FOR DESALINATION

[0028] In one aspect, a method for desalination of water (e.g., ground water, brackish water, ocean water, or other saline water) is described. The method makes use of a working fluid which has two relevant properties: it is not fully miscible with water (e.g., the working fluid is substantially non-polar) and the miscibility is temperature dependent. Saline input water is combined with the working fluid at a first temperature, allowing water to be absorbed into the working fluid. Because of low' polarity of the working fluid, the waler absorbed into the working fluid is less saline than the input water.

[0029] The working fluid-w'ater mixture is then brought to a second temperature, and water is allowed to separate from the working fluid at this second temperature. Depending on the nature of the working fluid, the second temperature might be higher or lower than the first temperature.

[0030] In some embodiments, the working fluid includes one or more substantially non-polar alcohols. For example, the working fluid can include a substantially non-polar alcohol. The substantially non-polar alcohol can have a dielectric constant (at, e.g., 20 °C) of about 20 or less. In some embodiments, the substantially non-polar alcohol can have a dielectric constant (at, e.g., 20 °C) of about 15 or less. The substantially non-polar alcohol can be a C4-C20alcohol, a C5-C18alcohol, or a C5-C12alcohol. In some embodiments, the substantially non- polar alcohol has an odd number of carbon atoms.

[0031] In some embodiments, the working fluid includes a straight or branched chain, primary, secondary', or tertiary alkyl or alkenyl alcohol of 4 or more carbons (e.g., a C4-C20alcohol). Straight chain and branched primary alkyl alcohols of 4 or more carbons include, for example, 1-butanol, 1 -pentanol, 1 -hexanol, 1 -heptanol, 1-octanol. 1 -nonanol, 1 -decanol, 1 -undecanol, 1 -dodecanol, 1 -tridecanol, 1 -tetradecanol, 1 -pentadecanol, 1 -hexadecanol, 1- heptadecanol, 1 -octadecanol, and isomers thereof (e.g., isobutanol, isoamyl alcohol, 2-ethyl- 1 -hexanol, 2-(n-propyl)-l -heptanol, etc.).

[0032] Straight chain secondary alkyl alcohols of 4 or more carbons include, for example, 2- butanol, 2 -pentanol, 3-pentanol, 2-hexanol, 3-hexanol, 2-heptanol, 3-heptanol, 2-octanol, 3- octanoL 2-nonanol, 3-decanol, and other positional isomers of the straight chain primary alcohols. Straight chain primary alkenyl alcohols of 4 or more carbons include, e.g., 1-hexen- 3-ol, 2-hexen-l-ol, 4-hexen-l-ol, and 5-hexen-l-ol.

[0033] Substantially non-polar alcohols including an aryl group include 1 -phenylethanol, 2- phenylethanol, 2 -methyl- 1 -phenyl-2-propanol, 2 -phenyl- 1 -propanol, 4-hydroxybenzyl alcohol, alpha-amyl cinnamyl alcohol, anisyl alcohol, cinnamyl alcohol, furfuryl alcohol, isoeugenol, and vanillyl alcohol.

[0034] Other substantially non-polar alcohols include alpha-campholenic alcohol, caryophyllene alcohol, beta-caryophyllene alcohol, borneol, isoborneol, carveol, cubebol, fenchyl alcohol, isopulegol, linalool, nerol, oleyl alcohol, phytol, sclareol, sorbitol, thujyl alcohol, zeranol, dexpanthenol, and diethylaminoethanol.

[0035] In some embodiments, the working fluid includes a mixture. The mixture can include a first substantially non-polar alcohol and second substantially non-polar component, such as an alkane, or a second substantially non-polar alcohol. For example, the mixture can include a first substantially non-polar alcohol, such as 1 -heptanol, and a second substantially non- polar alcohol, such as 3-pentanol. The mixture can be in any proportion, for example from about 0.1 mol% to about 99.9 mol% of the second substantially non-polar alcohol. In some embodiments, the first substantially non-polar alcohol is an alkyl alcohol (e.g., 1-heptanol or 1 -decanol) and the second substantially non-polar alcohol includes an aromatic group (for example, vanillyl alcohol or cinnamyl alcohol).

[0036] Some illustrative alcohols useful as the working fluid, or as a component of a working fluid mixture, are shown in Table 1.

[0037] Table 1: Example Alcohols.Molecular _ .. ......7,Oi ADensity SolubilityA ame and Structure weight . ,T" . „ . ~(s / mol) 'a / mLl<8 / L)1 -Heptadecanol1 -Hexanol10217 0814 591 -Octadecanol 11 -Phenyl- 1 PropanolMolecular.. ,, . , Density SolubilityName and Structure weight '1-TetradecaiiolMolecular.. ,, . , Density SolubilityName and Structure weight ' *2-(Hydroxymethyl)phenol2-Phenyl- 1 -propanolMolecularDensify SolubilityName and Structure Weight (g / mL) (g / mol) (g / L) ‘Molecular.. ,, . , Density SolubilityName and Structure weight ' *4-Phenyl-2-ButanolAlpha-Amyl Cinnamyl AlcoholBeta-Caryophyllene AlcoholMolecularDensity SolubilityName and Structure Weight (g / mL) (g / mol) (g / L) 'MolecularDensity SolubilityName and Structure Weight (g / mL) (g / mol) (g / L) 'Molecular.. ,, . , Density SolubilityName and Structure weight '(e / mol)Methanol34.042 0.7913 1000—OHNerolMolecular.. ,, . , Density SolubilityName and Structure weight '

[0038] II. SYSTEM FOR DESALINATION

[0039] In one aspect, systems for desalination of water are described . In general, the systems described herein include a vessel which holds a working fluid. The vessel accepts saline water (e.g., via an inlet) into the vessel where it becomes mixed with the working fluid in a first temperature zone. The vessel includes a second temperature zone which, during operation, is maintained at a temperature selected to favor separation of desalinated water from the working fluid. The vessel includes a desalinated water recovery. The desalinated water recovery can be located at a low point below or underneath the second temperature zone, such that desalinated water separating from the working fluid can collect at the outlet by virtue of gravity and higher density than the working fluid. The desalinated water recovery can be connected to a desalinated water outlet so that desalinated water can be readily withdrawn from the vessel. The vessel generally also includes a reject outlet, which may be in or proximate to the first temperature zone, which allows for saline water to be removed from the vessel. In some embodiments, the system is configured for continuous operation.

[0040] When the working fluid includes a substantially non-polar alcohol, the second temperature zone is typically warmer than the first temperature zone. For example, in some embodiments, the first temperature zone can be configured to maintain the working fluid at a temperature that is close to ambient temperature or below ambient temperature (e.g., in a temperature range of from about 0 °C to about 30 °C). The second temperature zone can be configured to maintain the working fluid at a higher-than- ambient temperature. For example.in some embodiments, the second temperature zone can be configured to maintain the working fluid in the range of about 60 °C to about 100 °C, in the range of about 65 °C to about 95 °C, or in the range of about 70 °C to about 90 °C. The second temperature zone can be configured to maintain the working fluid at about 60 °C, about 65 °C, about 70 °C, about 75 °C, about 80 °C, about 85 °C, about 90 °C, about 95 °C, or about 100 °C.

[0041] FIG. 1A is a schematic for an exemplary system 100 including vessel 110 which has a feed inlet 120 proximate to cold wall 130, and a hot wall 150 separate from cold wall 130. In operation, vessel 110 contains a working fluid 140 which contacts both cold wall 130 and hot wall 150. Vessel 110 also includes a reject outlet 160 proximate to cold wall 130 and a desalinated water outlet 170 proximate to hot wall 150. During operation, vessel 110 is charged with working fluid 140, and cold wall 130 and hot wall 150 are configured to maintain cold wall 130 at a lower temperature than hot wall 150.

[0042] FIG. IB illustrates a variation of system 100 that omits a cold wall. The feed inlet 120 is located at the top of vessel 110, adding saline w ater to working fluid 140. Mixer 125 mixes the saline water and working fluid and promotes movement of the mixtur e from the center of vessel 1 10 toward a wrall warmed by heater 145. Near or at the bottom of vessel 1 10, and proximate to the wall warmed by heater 145, is located a desalinated water outlet 170. Also near or at the bottom of vessel 110 is a reject outlet 160.

[0043] FIG. 2 illustrates a system 200 which includes vessel 210. Vessel 210 includes feed inlet 220 configured to feed saline water 230 near the bottom of vessel 210. In vessel 210, working fluid 240 sits above saline water 230. Optional mixer 250 (e g., a fluid fan, recirculating pump, combinations thereof, and the like) provides mixing action so that working fluid 240 is well mixed with saline water 230. This mixing action promotes the working fluid 240 to absorb water from saline water 230. Optional baffling 255 controls the movement of working fluid 240 in the volume of vessel 210. Optional cooling box 260 provides temperature control for the w orking fluid in vessel 210. Vessel 210 includes a hot finger 270 positioned above a desalinated water collector 280, which is connected to desalinated water outlet 285. Vessel 210 also includes reject outlet 290, configured to remove saline water 230 from near the bottom of vessel 210.

[0044] FIG. 3 illustrates a system 300 which operates in a similar manner to system 200. System 300 includes vessel 310, with feed inlet 320 configured to feed saline water 330 near the bottom of vessel 310. In vessel 310, working fluid 340 sits above saline water 330. Optional fluid fan 350 provides mixing action so that working fluid 340 is able to absorb w'ater from saline water 330. Optional baffling 355 controls the movement of working fluid340 in the volume of vessel 310. Optional cooling box 360 provides temperature control for the working fluid in vessel 310. Vessel 310 includes a number of hot fingers 370 positioned above desalinated water collectors 380, each of which is connected to a desalinated water outlet 385. Vessel 310 also includes reject outlet 390, configured to remove saline water 330 horn near the bottom of vessel 310.

[0045] FIG. 4 is a schematic diagram of a system 400 for desalination. System 400 includes vessel 405 with feed inlet 410 configured to add saline water to the inside of mixing chamber 415, where mixer 420 agitates the added saline water with dry working fluid supplied from working fluid inlet 425. The working fluid / saline mixture 430 passes through flow’ path 435 and past baffle 436 in holding chamber 437 before reaching laminar flow’ plate 440. The working fluid / saline mixture 430 passes through laminar flow’ plate 440 and enters process chamber 445. In process chamber 445, a reject outlet 450 removes w’ater that has separated from the working fluid / saline mixture 430. Working fluid 460 in process chamber 445 comes into contact w'ith hot fingers 465, causing desalinated water to separate from the working fluid and collect in the desalinated water collector 470. Desalinated w’ater can be removed from vessel 410 via desalinated w’ater outlet 475. After passing the hot fingers 465, dry’ working fluid can pass out of vessel 410 via working fluid outlet 480, into working fluid cooler 485, and return to the mixing chamber via loop 490 and inlet 425.

[0046] III. EXAMPLES

[0047] Example 1: Screening Protocol.

[0048] Various liquids were screened for use as working fluids in the desalination methods and systems described herein. Desalination of simulated well water w as tested as follow’s.

[0049] To prepare simulated w'ell w’ater (“Egypt 119 Water”), the salts listed in Table 2 were weighed in the order outlined below and combined into 2L of deionized w’ater.

[0050] Table 2: Salts for simulated well water.10051 ] Table 3 summarizes the ionic composition of the simulated well water.

[0052] Table 3: Composition of simulated well water.TDS means total dissolved solids.

[0053] First. 125 niL of the fluid to be screened were transferred by pipette into a clean 250 mL conical centrifuge tube using a 100 mL serological pipette. Next, 125 mL of the Egypt 119 Water was added to the 250 mL conical centrifuge tube. The tube was closed securely and the fluid and Egypt 119 Water were mixed by gently inverting the tube for 1 minute. After the minute of mixing time elapsed, the tube was placed in the tube rack and the phases were allowed to settle. Once the organic and aqueous phases had separated, the aqueous layer was pipetted out of the tube. The isolated aqueous layer was referred to as the “Reject’’ or “Reject Brine.”

[0054] Next, the 250 mL conical centrifuge tube with the organic layer was placed into a heated water bath at a set temperature (e.g., 70 °C, 80 °C, 85 °C, or 90 °C) and allowed to sit for ~1 horn-. Once the heating time elapsed, the conical centrifuge tube was carefully removed iiom the heated water bath and placed in a tube rack. Desorbed water was extracted at room temperature (—23 °C) and transferred with a clean 10 mL pipette to a clean vial, and the mass of recovered water was recorded. The extracted desorbed water was referred to as the “Recovered” or “Recovered Desalinated Water”. 1 mL of the Recovered Desalinated Water was added into a clean 15 mL test tube and diluted with 9 mL deionized water for analysis by inductively coupled plasma optical emission spectroscopy (ICP-OES) at a 1 Ox dilution factor.

[0055] Example 2: Individual alcohols.

[0056] A number of individual alcohols were tested according to the method described in Example 1 . Results are presented in Tables 4A and 4B. In Table 4A, “Water” refers to the amount of Recovered Desalinated Water (g). In Table 4B, “Ca,” “Mg,” “K,” “Na,” “SCU,” and “HCO3” are concentrations (mg / L) of calcium, magnesium, potassium, sodium, sulfate, and bicarbonate ions, respectively, in the Recovered Desalinated Water; and “Tot.” is total ion concentration in the Recovered Desalinated Water (mg / L).

[0057] Table 4A: Results (1 of 2) for individual alcohols.

[0058] Table 4B: Results (2 of 2) for individual alcohols.The Cl, K, and HCO3 ion concentrations in Table 4B were calculated based on the measured concentrations of counterions (from the starting material salts) present in the Recovered Desalinated Water and their relative solubilities.

[0059] Example 3: Alcohol mixtures.

[0060] Mixtures of alcohols were also tested as described in Example 1 . Results are presented in Tables 5 A and 5B. In Table 5 A, “Water” refers to the amount of Recovered Desalinated Water (g). In Table 5B, “Ca,” “Mg,” “K,” “Na,” “SO4,” and “HCOC are concentrations (mg / L) of calcium, magnesium, potassium, sodium, sulfate, and bicarbonate ions, respectively, in the Recovered Desalinated Water; and “Tot.” is total ion concentration in the Recovered Desalinated Water (mg / L).

[0061] Table 5A: Results (1 of 2) for alcohol mixtures.

[0062] Table 5B: Results (2 of 2) for alcohol mixtures.The Cl, K, and HCOs ion concentrations in Table 5B were calculated based on the measured concentrations of counterions (from the starting material salts) present in the Recovered Desalinated Water and their relative solubilities.

[0063] Example 4: Boron extraction.

[0064] The ability of the solvent extraction method to produce desalinated water with a reduced boron concentration compared to the starting saline water was tested.

[0065] Experimental Procedure

[0066] To prepare simulated well water (“Egypt 1 19 waler”) with and without boric acid, the following the salts listed in Tables 6 and 7 were weighed in the order outlined below and combined into IL of deionized water.

[0069] The Egypt 119 Water + Boric Acid simulated mixture was prepared by dissolving 1 g of boric acid in 500 mL of deionized (DI) water, adding DI water to give a final volume of 1 L, and adding the salts in the order presented in Table 6.

[0070] First, 125 mL of the fluid ( 1 -decanol or diisopropylamine (DIPA)) was transferred by pipette into a clean 250 mL conical centrifuge tube using a 100 mL serological pipette. Next, 125 mL of the Egypt 119 Water or the Egypt 119 Water + Boric Acid was added to the 250 mL conical centrifuge tube. The tube was closed securely and the fluid and Egypt 119 Water or the Egypt 119 Water + Boric Acid were mixed by gently inverting the tube for 1 minute. After the mixing time elapsed, the tube was placed in the tube rack and the phases were allowed to settle. Once the organic and aqueous phases had separated, the aqueous layer was pipetted out of the tube.The isolated aqueous layer was referred to as the “Reject” or “Reject Brine.”

[0071] Next, the 250 mL conical centrifuge tube with the organic layer was placed into a heated water bath at a set temperature of 85 °C and allowed to sit for ~1 hour. Once the heating time elapsed, the conical centrifuge tube was carefully removed from the heated water bath and placed in the tube rack. Desorbed water was extracted at room temperature (~23 °C) and transferred with a clean 10 mL pipette to a clean vial, and the mass of recovered water was recorded. The extracted desorbed water was referred to as the “Recovered” or “Recovered Desalinated Water”. 1 mL of the Recovered Desalinated Water was added into a clean 15 mL test tube and diluted with 9 mL deionized water for analysis by ICP-OES at a lOx dilution factor.

[0072] Results are summarized in Table 8. Whether 1 -decanol or DIPA was used in the extraction, the concentration of boron was greatly reduced in the recovered (i.e., desalinated) water compared to the starting concentration.

[0073] Table 8: Boron Extraction With and Without Well Salt PresentEQUIVALENTS AND SCOPE

[0074] In the claims articles such as “a,” “an,” and “the” may mean one or more than one unless indicated to the contrary or otherwise evident from the context. Claims or descriptions that include “or” between one or more members of a group are considered satisfied if one, more than one, or all of the group members are present in, employed in, or otherwise relevant to a given product or process unless indicated to the contrary or otherwise evident from the context. The invention includes embodiments in which exactly one member of the group is present in, employed in, or otherwise relevant to a given product or process. The invention includes embodiments in which more than one, or all of the group members are present in, employed in, or otherwise relevant to a given product or process.

[0075] Furthermore, the invention encompasses all variations, combinations, and permutations in which one or more limitations, elements, clauses, and descriptive terms from one or more of the listed claims is introduced into another claim. For example, any claim that is dependent on another claim can be modified to include one or more limitations found in any other claim that is dependent on the same base claim. Where elements are presented as lists, e.g., in Markush group format, each subgroup of the elements is also disclosed, and any element(s) can be removed from tire group. It should it be understood that, in general, where the invention, or aspects of the invention, is / are referred to as comprising particular elements and / or features, certain embodiments of the invention or aspects of the invention consist, or consist essentially of, such elements and / or features. For purposes of simplicity, those embodiments have not been specifically set forth in haec verba herein. It is also noted that the terms “comprising” and “containing” are intended to be open and pennits the inclusion of additional elements or steps. Where ranges are given, endpoints are included. Furthermore, unless otherwise indicated or otherwise evident from the context and understanding of one of ordinary’ skill in the art, values that are expressed as ranges can assume any specific value or sub-range within the stated ranges in different embodiments of the invention, to the tenth of the unit of the lower limit of the range, unless the context clearly dictates otherwise.10076 ] This application refers to certain issued patents, published patent applications, journal articles, and other publications, all of which are incorporated herein by reference. If there is a conflict between any of the incorporated references and the instant specification, the specification shall control. In addition, any particular embodiment of the present invention that falls within the prior art may be explicitly excluded from any one or more of the claims. Because such embodiments are deemed to be known to one of ordinary skill in the art, they may be excluded even if the exclusion is not set forth explicitly herein. Any particular embodiment of the invention can be excluded from any claim, for any reason, whether or not related to the existence of prior art.

[0077] Those skilled in the art will recognize or be able to ascertain using no more than routine experimentation many equivalents to the specific embodiments described herein. The scope of the present embodiments described herein is not intended to be limited to the above Description, but rather is as set forth in the appended claims. Those of ordinary skill in the art will appreciate that various changes and modifications to this description may be made without departing from the spirit or scope of the present invention, as defined in the following claims.

Claims

WHAT TS CLAIMED IS:

1. A method of water desalination comprising:(a) providing a vessel which comprises: a cold zone; a hot zone; a working fluid comprising a substantially non-polar alcohol spanning the cold zone and the hot zone; a feed water inlet configured to mix saline water with the working fluid in the cold zone; a reject outlet configured to remove saline water from the working fluid in the cold zone; and a desalinated water outlet configured to remove desalinated water from the working fluid in the hot zone; wherein the hot zone is configured to be maintained at a substantially warmer temperature than the cold zone;(b) adding saline water to the vessel via the feed water inlet; and(c) removing desalinated water from the vessel via the desalinated water outlet.

2. The method of claim 1, wherein the hot zone comprises a wall of the vessel.

3. The method of claim 1, wherein the hot zone comprises a hot finger in the vessel.

4. The method of claim 1, wherein the vessel further comprises a desalinated water collector.

5. The method of claim 4, wherein the desalinated water collector is positioned below the hot zone and is connected to the desalinated water outlet.

6. The method of claim 1, wherein the vessel further comprises one or more mixers positioned to mix working fluid and saline water.

7. The method of claim 1, wherein the vessel further comprises one or more baffles.

8. The method of claim 1, wherein the vessel further comprises one or more cooling boxes.

9. The method of any one of claims 1 -8, wherein the working fluid comprises a C4-C25alcohol.

10. The method of claim 9, wherein the working fluid comprises a C6-C18alcohol.

11. The method of claim 10, wherein the working fluid comprises a C7-C15alcohol having an odd number of carbon atoms.

12. The method of any one of claims 1-11, wherein the working fluid comprises 1 -pentanol, 2 -pentanol, isoamyl alcohol, 1 -hexanol, 2 -hexanol, 3-hexanol, 1 -heptanol, 1 -octanol, 2-ethyl-l- hexanol, 1 -nonanol, 2-nonanol, 1 -decanol, 1 -undecanol, or 1 -dodecanol.

13. The method of any one of claims 1-12, wherein the working fluid comprises a first substantially non-polar alcohol and a second substantially non-polar alcohol.

14. The method of any one of claims 1-13, wherein die concentration of boron in the desalinated water is lower than the concentration of boron in the saline water.

15. A system for the desalination of water comprising a vessel which comprises: a cold zone; a hot zone; a working fluid comprising a substantially non-polar alcohol spanning the cold zone and the hot zone; a feed water inlet configured to mix saline water with the working fluid in the cold zone; a reject outlet configured to remove saline water from the working fluid in the cold zone; anda desalinated water outlet configured to remove desalinated water from the working fluid in the hot zone; wherein the hot zone is configured to be maintained at a substantially warmer temperature than the cold zone.

16. The system of claim 15, wherein the hot zone comprises a wall of the vessel.

17. The system of claim 15, wherein the hot zone comprises a hot finger in the vessel.

18. The system of claim 15, wherein the vessel further comprises a desalinated water collector.

19. The system of claim 18, wherein the desalinated water collector is positioned below the hot zone and is connected to the desalinated water outlet.

20. The system of claim 15, wherein the vessel further comprises one or more mixers positioned to mix working fluid and saline water.

21. The system of claim 15, wherein the vessel further comprises one or more baffles.

22. The system of claim 15, wherein the vessel further comprises one or more cooling boxes.

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