Humidity-conditioning liquid, method for producing humidity-conditioning liquid, humidity-conditioning method, and humidity-conditioning device

Abstract

To provide a humidity-conditioning liquid having reduced corrosiveness to metals, a method for manufacturing the humidity-conditioning liquid, a humidity-conditioning method, and a humidity-conditioning device. [Solution] The present invention provides a humidity-conditioning liquid containing lithium chloride, water, a water-soluble rust inhibitor, and an ionic liquid; a method for producing a humidity-conditioning liquid including a step of preparing an additive by mixing an ionic liquid aqueous solution containing an ionic liquid and water with the water-soluble rust inhibitor; and a step of mixing the additive with an aqueous lithium chloride solution containing lithium chloride and water; and a humidity control device including a humidity control section that brings the humidity-conditioning liquid into contact with air.

Description

[Technical Field]

[0001] The present disclosure relates to a humidity-conditioning liquid, a method for producing a humidity-conditioning liquid, a humidity-conditioning method, and a humidity-conditioning device. [Background technology]

[0002] Liquid desiccant air conditioners that use a humidity-controlling liquid are known as air conditioners that efficiently achieve ventilation and humidity control. In liquid desiccant air conditioners, the temperature and humidity of air that comes into contact with the humidity-controlling liquid are controlled by controlling the temperature and concentration of the humidity-controlling liquid. For example, a lithium chloride aqueous solution containing lithium chloride and water is used as a humidity-controlling liquid with high humidity-controlling performance.

[0003] However, because lithium chloride aqueous solution is highly corrosive to metals, in liquid desiccant air conditioners that use lithium chloride aqueous solution as a humidity-conditioning liquid, measures have been taken such as limiting the metal used in the metal parts that come into contact with the lithium chloride aqueous solution to titanium. It is also known to use liquids other than aqueous lithium chloride solutions, such as ionic liquids, as humidity-conditioning liquids that suppress corrosion of metals (Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6046294 Summary of the Invention [Problem to be solved by the invention]

[0005] A lithium chloride aqueous solution has a disinfecting effect, and the lithium chloride used as a humidity control agent does not evaporate and is a stable substance, making it preferable as a humidity control liquid. On the other hand, metals are used as the main material for humidity control devices, heat exchangers, etc. that may come into contact with humidity control liquid, and copper in particular is preferably used for these devices because of its good workability, corrosion resistance, thermal conductivity, etc. Therefore, it has been desired to suppress the corrosiveness of a humidity control liquid using an aqueous lithium chloride solution to metals.

[0006] An object of one embodiment of the present disclosure is to provide a humidity conditioning liquid that is less corrosive to metals, a method for manufacturing a humidity conditioning liquid, a humidity conditioning method, and a humidity conditioning device. [Means for solving the problem]

[0007] The present disclosure includes the following aspects.

[0008] <1> A humidity control liquid containing lithium chloride, water, a water-soluble rust inhibitor, and an ionic liquid. <2> The water-soluble rust inhibitor is benzotriazole. <1> The humidity-conditioning liquid described in <3> Ionic liquids have the ability to absorb and release water. <1> or <2> The humidity-conditioning liquid described in <4> The ionic liquid contains imidazolium <1> ~ <3> The humidity-conditioning liquid according to any one of the above. <5> A method for producing a humidity-conditioning liquid includes: a step of preparing an additive by mixing an ionic liquid aqueous solution containing an ionic liquid and water with a water-soluble rust inhibitor; and a step of mixing an aqueous lithium chloride solution containing lithium chloride and water with the additive. <6> The additives are mixed in a range of 1% by mass to 45% by mass based on the total mass of the humidity-conditioning liquid. <5> A method for producing the humidity-conditioning liquid described in <7> The lithium chloride aqueous solution contains lithium chloride in a range of 20% by mass to 40% by mass based on the total mass of the lithium chloride aqueous solution. <5> or <6> A method for producing the humidity-conditioning liquid described in <8> <1> ~ <4> 10. A humidity control method for controlling humidity using the humidity control liquid according to any one of the above items. <9> <1> ~ <4> 10. A humidity control device comprising a humidity control section that brings the humidity control liquid according to any one of the above into contact with air. <10> At least a part of the portion that comes into contact with the humidity control liquid contains copper. <9> The humidity control device according to claim 1. [Effects of the Invention]

[0009] According to an embodiment of the present disclosure, it is possible to provide a humidity conditioning liquid with reduced corrosiveness, a method for manufacturing a humidity conditioning liquid, a humidity conditioning method, and a humidity control device. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is an explanatory diagram illustrating the configuration of a liquid desiccant air conditioner. [Figure 2] 1 is a graph showing the relationship between elapsed time (hours) and the weight ratio of the tube in Examples and Comparative Examples. DETAILED DESCRIPTION OF THE INVENTION

[0011] Specific embodiments of the humidity-conditioning liquid, the method for producing the humidity-conditioning liquid, and the humidity-conditioning device according to the present disclosure are described in detail below. However, the humidity-conditioning liquid, the method for producing the humidity-conditioning liquid, and the humidity-conditioning device according to the present disclosure are not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the object of the present disclosure.

[0012] In the present disclosure, a numerical range indicated using "to" means a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the present disclosure, the upper or lower limit of a numerical range described in stages may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in the present disclosure, the upper or lower limit of a numerical range described in stages may be replaced with a value shown in the examples. In the present disclosure, a combination of two or more preferred embodiments is a more preferred embodiment. In the present disclosure, "mass %" and "weight %" are synonymous. In the present disclosure, when there are multiple substances corresponding to each component, the amount of each component means the total amount of the multiple substances unless otherwise specified. In this disclosure, "room temperature" means 25°C.

[0013] <Humidity control liquid> A humidity-conditioning liquid according to an embodiment of the present disclosure includes lithium chloride, water, a water-soluble rust inhibitor, and an ionic liquid. In this embodiment, the lithium chloride and a portion of the water contained in the humidity-conditioning liquid are based on the lithium chloride aqueous solution used in producing the humidity-conditioning liquid, and the ionic liquid and a portion of the water are based on the ionic liquid aqueous solution used in producing the humidity-conditioning liquid.

[0014] Humidity-conditioning liquids containing an aqueous lithium chloride solution have high humidity-conditioning performance, a disinfecting effect, and lithium chloride is a stable substance that does not evaporate. Therefore, they are preferably used as humidity-conditioning liquids in humidity-conditioning devices such as liquid desiccant air conditioners. Specifically, with regard to humidity-conditioning performance, humidity-conditioning liquids containing an aqueous lithium chloride solution can accurately control the water vapor pressure of the air they come into contact with by combining the temperature and the lithium chloride concentration, making it possible to obtain air at a desired temperature and humidity. In particular, because there is no need to cool the air to the desired dew point temperature during dehumidification, the temperature of the cold source can be increased compared to general cooling dehumidification methods, resulting in excellent energy savings.

[0015] However, since a lithium chloride aqueous solution is highly corrosive to metals, in a humidity control device using a humidity control liquid containing a lithium chloride aqueous solution, if a portion that comes into contact with the humidity control liquid contains metal, it has been necessary to take measures such as using a metal that is resistant to corrosion by a lithium chloride aqueous solution, such as titanium.

[0016] The present inventors investigated adding a rust inhibitor to a humidity-conditioning liquid to reduce the corrosiveness of metals, in order to enable the use of inexpensive, general-purpose metals, such as copper, for the metal parts of a humidity-conditioning device that come into contact with a humidity-conditioning liquid containing an aqueous lithium chloride solution. However, for example, when a water-soluble rust inhibitor that is believed to be capable of reducing corrosiveness to copper is added to a lithium chloride aqueous solution, it was found that the water-soluble rust inhibitor is hardly soluble in the lithium chloride aqueous solution at room temperature, for example, 25°C, at which a humidity-conditioning liquid is used, and that even if the water-soluble rust inhibitor is dissolved at a high temperature, the water-soluble rust inhibitor may precipitate as the temperature decreases.

[0017] Therefore, in order to obtain a humidity-conditioning liquid that maintains high humidity-conditioning performance while reducing corrosiveness, the addition of a water-soluble rust inhibitor to the lithium chloride aqueous solution was further investigated, and it was found that the water-soluble rust inhibitor is easily miscible with the lithium chloride aqueous solution in the presence of the ionic liquid. They also discovered that a humidity-conditioning liquid, which is a mixture of an ionic liquid containing a water-soluble rust inhibitor dissolved therein and an aqueous lithium chloride solution, reduces the corrosiveness of copper and copper alloys in particular and has high humidity-conditioning performance.

[0018] Although the mechanism by which the above-mentioned effect is exerted is not clear, it is speculated that the water-soluble rust inhibitor dispersed in the lithium chloride aqueous solution due to the presence of the ionic liquid functions appropriately in the system to form a coating on the metal, such as copper or a copper alloy, thereby imparting to the metal the effect of reducing the corrosiveness of the lithium chloride aqueous solution to the metal.

[0019] (lithium chloride aqueous solution) The humidity control liquid contains lithium chloride and water. Lithium chloride is used as a humidity control agent because it has hygroscopic properties. One type of humidity control agent may be used, or two or more types may be used. A humidity-controlling liquid containing a humidity-controlling agent and water controls the gas-liquid equilibrium vapor pressure by controlling the concentration, thereby controlling the humidity of the air. For example, when the air humidity is high, the humidity-controlling liquid is concentrated by, for example, heating the humidity-controlling liquid to evaporate the water, thereby increasing the concentration of the humidity-controlling agent in the humidity-controlling liquid, and the concentrated humidity-controlling agent absorbs moisture in the air, thereby reducing the humidity. On the other hand, when the air humidity is low, the humidity of the humidity-controlling agent in the humidity-controlling liquid is reduced by, for example, supplying water to the humidity-controlling liquid, and the reduced-concentration humidity-controlling liquid adds moisture to the air, thereby increasing the humidity.

[0020] In addition to lithium chloride, metal halide salts such as lithium bromide and calcium chloride can be used as the humidity control agent. A lithium chloride aqueous solution has a disinfecting effect, and lithium chloride does not evaporate, making it a stable and safe substance. Therefore, it is preferable to use lithium chloride as the humidity control agent. Furthermore, an ionic liquid or an ionic liquid aqueous solution can also be used as the humidity control agent. Ionic liquids will be described later.

[0021] The water used for the humidity control liquid is preferably highly pure water from the viewpoints of appropriately controlling humidity, preventing indoor contamination, and concentrating residues through evaporation. For example, it is preferable to use reverse osmosis (RO) water purified using a reverse osmosis membrane.

[0022] The lithium chloride concentration in the lithium chloride aqueous solution varies for humidity control purposes, but is preferably in the range of 20% by mass to 40% by mass, more preferably 25% by mass to 40% by mass, and even more preferably 25% by mass to 35% by mass, based on the total mass of the lithium chloride aqueous solution. Within this range, the relative humidity of the air in contact with the humidity control liquid can be more appropriately controlled.

[0023] The content of the lithium chloride aqueous solution in the humidity-conditioning liquid is preferably within a range of 55% by mass to 99% by mass based on the total mass of the humidity-conditioning liquid. In the humidity-conditioning liquid, the remainder other than the additives described below can be the lithium chloride aqueous solution. In the humidity-conditioning liquid, the amount and concentration of the rust inhibitor can be determined based on the amount of lithium chloride, the concentration of the lithium chloride aqueous solution, the temperature, etc., and the concentration or amount of the ionic liquid aqueous solution can be determined based on the amount and concentration of the rust inhibitor. When the content of the lithium chloride aqueous solution in the humidity-conditioning liquid is within the above range, the humidity-conditioning performance of the humidity-conditioning liquid can usually be more appropriately exhibited.

[0024] (Water-soluble rust inhibitor) The humidity-conditioning liquid contains a water-soluble rust inhibitor. Examples of the water-soluble rust inhibitor include conventionally used known rust inhibitors (such as those described in "Corrosion Reactions and Their Control" by HH Urick and RW Levy, published by Sangyo Tosho Co., Ltd.). Specific examples include organic amines having 7 to 18 carbon atoms, aliphatic amides having 6 to 18 carbon atoms, aromatic amides, cyclohexylamine nitrite, benzotriazole, mercaptobenzothiazole, N,N'-disalicylidene-1,2-diaminopropane, and alizarin.

[0025] Of these, benzotriazole and mercaptobenzothiazole are preferred because they are highly effective in reducing the corrosiveness of copper and its alloys used in humidity control devices, etc., and benzotriazole is more preferred because it is particularly effective in preventing rust on copper. The water-soluble rust inhibitor may be used alone or in combination of two or more.

[0026] (ionic liquid aqueous solution) The humidity-conditioning liquid contains an ionic liquid. Ionic liquids are salts that are liquid at room temperature and contain a cation and an anion. Many types of ionic liquids are known, and conventionally used known ionic liquids can be used. The ionic liquid is preferably one that is compatible with water at the temperature of the usage environment. The ionic liquid is preferably used as an ionic liquid aqueous solution mixed with water. Note that one type of ionic liquid may be used, or two or more types may be used in combination.

[0027] It is preferable that the ionic liquid itself or an ionic liquid aqueous solution has water absorption and release properties. The water absorption and release properties of the ionic liquid or ionic liquid aqueous solution (hereinafter referred to as ionic liquid, etc.) are such that they have excellent water absorption and release properties under the conditions in which the ionic liquid, etc. is used as a humidity-conditioning liquid. Such conditions include the temperature of the ionic liquid, etc., and the environment in which it is used. For this reason, it is preferable that the ionic liquid or the like has humidity-controlling performance. That is, it is preferable that the ionic liquid or the like is used as a humidity control agent. This is because the humidity control agent as a whole can be used as a humidity control liquid with more preferable humidity control performance. In this specification, the term "water absorbing and releasing" includes "moisture absorbing and releasing property" and refers to the ability to absorb and release moisture contained in the air, such as water vapor and water droplets. The ionic liquid preferably has antibacterial or disinfecting properties. Preferably, the ionic liquid has disinfecting properties and does not impair the disinfecting properties when mixed with an aqueous lithium chloride solution to form a humidity-conditioning liquid.

[0028] The viscosity of the ionic liquid or the like is preferably such that it has an appropriate fluidity for use as a humidity-conditioning liquid when mixed with an aqueous lithium chloride solution, and while there is no particular limitation on the lower limit, the upper limit is preferably, for example, 50 mPa s or less, and more preferably 30 mPa s or less, at room temperature at the concentration used as an aqueous ionic liquid solution.

[0029] Examples of ionic liquids include those in which the cation is an imidazolium-based, ammonium-based, or pyridinium-based compound. Specifically, those described in JP-A-2019-063761 and JP-A-2020-030004 can be used.

[0030] Among these, ionic liquids containing imidazolium as the cation are preferred because they have suitable humidity-regulating performance and antibacterial or disinfecting performance, etc. Furthermore, ionic liquids that can suitably dissolve water-soluble rust inhibitors and are miscible with an aqueous lithium chloride solution are preferred, and suitable examples of suitable ionic liquids include 1,3-dimethylimidazolium acetate, 1,3-dimethylimidazolium acetate, 1,3-dimethylimidazolium methylsulfonate, 1-ethyl-3-methylimidazolium diethylphosphate, and 1,3-dimethylimidazolium propionate. The ionic liquid may be used alone or in combination of two or more.

[0031] The concentration of the ionic liquid in the ionic liquid aqueous solution is not particularly limited, but is preferably 50% by mass to 95% by mass, and more preferably 65% ​​by mass to 80% by mass, based on the total mass of the ionic liquid aqueous solution.

[0032] The ionic liquid aqueous solution may be a commercially available product. An example of a commercially available product is an imidazolium salt aqueous solution (product name: CreCOPlus (registered trademark), manufactured by Evonik). CreCOPlus is an imidazolium salt aqueous solution in which 80 mass % of the total mass is imidazolium salt.

[0033] (additives) The additive includes a water-soluble rust inhibitor, an ionic liquid, and water. In the additive, the ionic liquid and water are based on an ionic liquid aqueous solution. That is, the additive includes an ionic liquid aqueous solution and a water-soluble rust inhibitor. The additive is added to an aqueous lithium chloride solution prepared from lithium chloride and water. By adding the additive to the aqueous lithium chloride solution, it becomes possible to mix the aqueous lithium chloride solution with the water-soluble rust inhibitor while suppressing precipitation of the water-soluble rust inhibitor, and it is possible to impart a corrosiveness-reducing effect to the aqueous lithium chloride solution. The additives may be used alone or in combination of two or more.

[0034] From the viewpoint of solubility in an ionic liquid aqueous solution, the amount of the water-soluble rust inhibitor used in the additive is, for example, preferably in the range of 3 mass % to 20 mass %, and more preferably in the range of 5 mass % to 15 mass %, based on the total mass of the additive. The amount of the water-soluble rust inhibitor used in the entire humidity-conditioning liquid is preferably 0.02M (mol / L) to 0.8M, and more preferably 0.04M to 0.6M.

[0035] The additives can be mixed in any ratio in the humidity-conditioning liquid to obtain a homogeneous humidity-conditioning liquid. Based on the mass of the entire humidity-conditioning liquid, the additives are preferably used in a range of, for example, 1% by mass to 45% by mass, and more preferably 5% by mass to 40% by mass.

[0036] The proportion of the additive in the humidity-conditioning liquid may be determined depending on the desired humidity-conditioning liquid. To utilize the water absorption / release or humidity-conditioning performance of lithium chloride, the proportion of the additive can be set so that the lithium chloride aqueous solution is the main component and the additive can exhibit corrosion-reducing performance. In this case, the proportion of the additive in the humidity-conditioning liquid is, for example, preferably 1% by mass to 15% by mass, more preferably 3% by mass to 8% by mass, based on the mass of the entire humidity-conditioning liquid. In addition, the mixing ratio of the additives can be determined by adjusting the physical properties of the humidity-conditioning liquid, the temperature at which the humidity-conditioning liquid is used, the type of humidity-conditioning device that uses the humidity-conditioning liquid, and the like.

[0037] (Other ingredients) The humidity-conditioning liquid may contain other components other than lithium chloride, water, a water-soluble rust inhibitor, and the ionic liquid. The other components may be known additives conventionally used in humidity-conditioning liquids, and one or more of these components may be used. Specific other components are not particularly limited, but examples include known additives such as flame retardants, colorants, antifoaming agents, viscosity adjusters, and pH adjusters. Other components in the humidity-conditioning liquid can be used within a range that does not impair the effects of the humidity-conditioning liquid.

[0038] <Method of manufacturing humidity control liquid> A method for producing a humidity control liquid according to one embodiment of the present disclosure includes a step of preparing an additive by mixing an ionic liquid aqueous solution containing an ionic liquid and water with a water-soluble rust inhibitor (hereinafter referred to as an additive preparation step), and a step of mixing an aqueous lithium chloride solution containing lithium chloride and water with the additive (hereinafter referred to as a mixing step).

[0039] The above-described production method makes it possible to suppress the precipitation of a water-soluble rust inhibitor that is almost insoluble in a lithium chloride aqueous solution and precipitates at the use temperature of the humidity-conditioning liquid even if it dissolves in the lithium chloride aqueous solution by heating, and thereby to favorably dissolve the water-soluble rust inhibitor, thereby making it possible to reduce the corrosiveness of a humidity-conditioning liquid containing a lithium chloride aqueous solution to metals.

[0040] In particular, it becomes possible to dissolve benzotriazole, which is a water-soluble rust inhibitor that has high corrosion-reducing performance against copper and copper alloys, in an amount that suitably exhibits corrosion-reducing performance in a lithium chloride aqueous solution, and it becomes possible to impart corrosion-reducing properties against metals containing copper to a humidity-conditioning liquid that uses a lithium chloride aqueous solution. Furthermore, after dissolving benzotriazole in the humidity-conditioning liquid, precipitation of benzotriazole can be suppressed within the temperature range in which the humidity-conditioning liquid is used.

[0041] Furthermore, the method for producing the humidity-conditioning liquid is not limited to the above-described method. Any method that can ultimately produce a humidity-conditioning liquid can be employed. For example, the method may include a step of preparing a stock solution by mixing an ionic liquid aqueous solution containing an ionic liquid and water with a lithium chloride aqueous solution containing lithium chloride and water, and a step of mixing a water-soluble rust inhibitor with the stock solution.

[0042] According to the method for producing a humidity-conditioning liquid according to one embodiment of the present disclosure, it is possible to provide a humidity-conditioning liquid that reduces the corrosiveness of metals such as copper and copper alloys. For example, the main material of most heat exchangers is copper, and even when the main material is something other than copper, the brazing material often contains copper because of its good workability, corrosion resistance, thermal conductivity, etc. Therefore, it becomes possible to use a humidity-conditioning liquid comprising an aqueous lithium chloride solution, which is suitable as a humidity-conditioning liquid, in heat exchangers that are generally and widely used, thereby significantly expanding the range of use of humidity-conditioning liquids containing an aqueous lithium chloride solution.For this reason, many of the parts used in air conditioners are made of copper or copper alloys, and a liquid humidity control agent that does not corrode copper is extremely valuable.

[0043] (Additive adjustment process) The method for producing the humidity-conditioning liquid includes an additive preparation step of mixing an ionic liquid aqueous solution containing an ionic liquid and water with a water-soluble rust inhibitor to prepare an additive.

[0044] In the additive preparation step, an ionic liquid aqueous solution and a water-soluble rust inhibitor are prepared and then mixed together. In the additive preparation step, the method for mixing the ionic liquid aqueous solution and the water-soluble rust inhibitor is not particularly limited, and they may be mixed by any conventionally known method.

[0045] In the additive preparation step, for example, various operations such as heating and stirring may be performed when mixing the ionic liquid aqueous solution and the water-soluble rust inhibitor.

[0046] (Mixing process) The method for producing a humidity control liquid includes a mixing step of mixing an additive with an aqueous lithium chloride solution containing lithium chloride and water. The mixture prepared in the mixing step can be used as the humidity control liquid.

[0047] In the mixing step, an ionic liquid aqueous solution containing an ionic liquid, water, and a water-soluble rust inhibitor, and a lithium chloride aqueous solution containing lithium chloride and water are prepared and mixed together. In the mixing step, the method for mixing the ionic liquid aqueous solution and the lithium chloride aqueous solution is not particularly limited, and they may be mixed by a conventionally known method.

[0048] In the mixing step, various operations such as heating and stirring that are conventionally performed on an aqueous lithium chloride solution, an aqueous ionic liquid solution, etc. may be performed. In the method for producing the humidity-conditioning liquid, the preferred amounts of each component to be used are the same as those described above for the humidity-conditioning liquid.

[0049] <Humidity control method> A humidity control method according to one embodiment of the present disclosure performs humidity control using the humidity control liquid. By using the humidity-conditioning liquid, it is possible to control the humidity of the air with excellent energy efficiency and good humidity control.

[0050] The humidity control method includes a step of contacting a humidity control liquid with air. According to Raoult's law, the principle of humidity control is that the relative humidity of air when equilibrium is reached between the air and the humidity control liquid decreases as the concentration of the humidity control agent in the humidity control liquid increases. Therefore, the humidity of the air (gas-liquid equilibrium vapor pressure) can be adjusted by adjusting the concentration of the humidity control agent in the humidity control liquid.

[0051] By using the humidity control method according to an embodiment of the present disclosure, the concentration of the humidity control agent contained in the humidity control liquid can be adjusted by a conventionally known method, thereby enabling suitable humidity control. Note that the humidity control method may be performed while ventilation is also being performed.

[0052] <Humidity control device> One embodiment of the present disclosure is a humidity control device including a humidity control unit that brings the humidity control liquid according to the embodiment of the present disclosure into contact with air. The humidity control unit is a means for performing a humidity control function of adjusting the humidity of the taken-in air.

[0053] Specifically, the humidity control section can employ a means for bringing the humidity control liquid into contact with the air, and various conventionally known means can be used, such as a means for supplying the humidity control liquid from the top to the bottom of the processor and passing the taken-in air through the inside of the processor.

[0054] The humidity control section may also have a temperature control function for controlling the temperature of the air taken in. The temperature control function can be achieved, for example, by controlling the temperature of a humidity control liquid in the humidity control section.

[0055] In the humidity control device, at least a portion of the portion that comes into contact with the humidity control liquid may contain copper. In the humidity control device, the humidity control liquid may be heated using a heat exchanger. Heat exchangers are often made of materials containing copper because of their high thermal conductivity. Therefore, by using a humidity control liquid that has corrosion-reducing properties against metals in the humidity control device, various types of heat exchangers can be employed, and this is preferable in terms of thermal efficiency.

[0056] A specific example of a humidity control device equipped with a humidity control section is a liquid desiccant air conditioner. An example of a liquid desiccant air conditioner is shown in Fig. 1. As shown in Fig. 1, the liquid desiccant air conditioner 10 includes a processor 20 and a regenerator 30. The processor 20 functions as the humidity control section.

[0057] The processor 20 takes in air through an air intake port 21 and discharges the treated air through an exhaust port 22. The treatment device 20 is equipped therein with a humidity control liquid 23 and a gas-liquid contactor 24. The treatment device 20 also has a humidity control liquid outlet 25 and a humidity control liquid supply port 26, and the adjusted humidity control liquid 23 is supplied to the upper part of the gas-liquid contactor 24, passes through the inside of the gas-liquid contactor 24, and is stored in the lower part of the treatment device 20. The stored humidity control liquid 23 is discharged from the humidity control liquid outlet 24, passes through a heat exchanger 41, and is supplied to the regenerator 30.

[0058] The regenerator 30 takes in air through an air intake port 31 and discharges the treated air through an exhaust port 32 . The regenerator 30 has therein a humidity control liquid 33 and a gas-liquid contactor 34. The regenerator 30 also has a humidity control liquid outlet 35 and a humidity control liquid supply port 36, and the adjusted humidity control liquid 33 is supplied to the upper part of the gas-liquid contactor 34, passes through the inside of the gas-liquid contactor 34, and is stored in the lower part of the regenerator 30. The stored humidity control liquid 33 is discharged from the humidity control liquid outlet 35 and supplied to the processor 20 via a heat exchanger 41. Heat is transferred to the multiple heat exchangers 41 by a heat pump 42.

[0059] In the treatment device 20, during dehumidification, cooled humidity-control liquid 23 is brought into contact with air to cool and dehumidify the air. In the regenerator 30, the humidity-control liquid is heated to concentrate the humidity-control liquid. During humidification, heated humidity-control liquid 23 is brought into contact with air to heat and humidify the air. In the regenerator 30, water is supplied to the humidity-control liquid 33 to dilute the humidity-control liquid 33. [Example]

[0060] Next, the humidity-conditioning liquid and the like according to the present disclosure will be described in more detail with reference to examples. Note that the humidity-conditioning liquid and the like according to the present disclosure are not limited to these examples in any way.

[0061] In the examples and comparative examples, the humidity-conditioning liquid was prepared according to the following procedure. The obtained humidity-conditioning liquid was then used to evaluate its ability to reduce corrosiveness to metals. The results are shown in Table 1.

[0062] [Example] <Adjusting the humidity control liquid> (Preparation of Additive A) An additive containing an ionic liquid aqueous solution and a water-soluble rust inhibitor was prepared. An 80% by mass imidazolium salt aqueous solution (product name: CreCOPlus, manufactured by Evonik) was used as the ionic liquid aqueous solution, and benzotriazole was used as the water-soluble rust inhibitor. Additive A was prepared by mixing 20 ml of CreCOPlus with benzotriazole in an amount to give a concentration of 0.04 M (mol / L) for a total of 400 ml of humidity-conditioning solution A containing 20 ml of additive A and 380 ml of lithium chloride aqueous solution.

[0063] (Preparation of lithium chloride aqueous solution) The lithium chloride aqueous solution was prepared by adding tap water so that the lithium chloride concentration was 30 mass %.

[0064] (Preparation of Humidity Conditioning Solution A) Humidity conditioning liquid A was prepared by mixing 20 mL of additive (approximately 5% by mass relative to the total mass of humidity conditioning liquid A) and 380 mL of aqueous lithium chloride solution (approximately 95% by mass relative to the total mass of humidity conditioning liquid A).

[0065] [Comparative Example] <Preparation of Humidity Conditioning Solution B> Humidity-conditioning liquid B was prepared in the same manner as humidity-conditioning liquid A in Example 1, except that no water-soluble rust inhibitor was added. In other words, only an ionic liquid aqueous solution was used as additive B.

[0066] <Evaluation> The humidity-conditioning liquids A and B were subjected to the corrosion test described below, and the amount of corrosion in the humidity-conditioning liquids was evaluated over time.

[0067] =Corrosion test= The corrosion test was carried out by placing 400 mL of humidity-conditioning liquid A in a lidded bottle, maintaining the temperature at 45°C, and stirring the humidity-conditioning liquid A with a magnetic stirrer. The copper tube was suspended by a nylon string and adjusted to be positioned in the middle of the liquid height. The tube used was made of phosphorus-deoxidized copper (JIS C1220T), with an outer diameter of 15.88 mm, an inner diameter of 14.63 mm, and a length of 22 mm.

[0068] The time after immersion was measured, and after a certain time had passed, the tube was taken out and weighed. After measuring the weight, the tube was immersed again in the humidity-conditioning liquid. The weight of the tube was measured 11 times in total, from before immersion until after approximately 3000 hours had elapsed.

[0069] The time elapsed from the start of immersion was recorded, and the weight was measured and recorded at regular intervals. When measuring the weight, any compound adhesion was removed, washed with pure water, and then thoroughly dried. At the very beginning, a small amount of verdigris-like deposit was found where the nylon thread had been in contact, and after removing it, no deposits were found thereafter, which was the reason for the relatively large weight loss observed when the first weight measurement was taken. Humidity-conditioning liquid A is a nearly colorless, transparent liquid, and no visible changes were observed during the test.In addition, no reaction was observed in a simple test using copper ion test paper, which can detect copper ion concentrations of 2 mg / L or more. The copper tubes appeared slightly darker, but retained the copper luster characteristic of the addition of benzotriazole.

[0070] The elapsed time (unit: hours) and the weight of the tube were measured. The weight ratio and the weight loss rate, with the weight at the first measurement taken as 1, were calculated and shown in Table 1. As shown in Figure 2, a graph was created showing the relationship between elapsed time (hours) and weight ratio, which showed that the weight of the tube hardly changed from approximately 200 hours to approximately 3,000 hours.

[0071] In addition to carrying out the corrosion test for humidity-conditioning liquid A as described above, a corrosion test was also carried out in the same manner as for humidity-conditioning liquid A for humidity-conditioning liquid B, which is the same mixed liquid as humidity-conditioning liquid A except that benzotriazole was not added. In the case of humidity-conditioning liquid B, after 24 hours, the liquid, which was initially almost colorless and transparent, had turned cloudy green-blue, indicating that corrosion was progressing rapidly. When the copper tube was inspected, no deposits were found, but it had completely lost its luster, suggesting that general corrosion had progressed. The elapsed time (unit: hours) and the weight of the tube were measured, and the weight ratio and the weight loss rate, assuming that the weight at the first measurement was 1, were calculated and listed in Table 1. If no test was conducted, this is indicated by leaving a blank in Table 1.

[0072] [Table 1]

[0073] 2, it was confirmed that in the example using humidity-conditioning liquid A, which is an embodiment of the present disclosure, the weight of the tube hardly changed and no generation or growth of corrosion products was observed up to approximately 3,000 hours after the test. In contrast, in the comparative example using humidity-conditioning liquid B, after 24 hours, the liquid, which was initially nearly colorless and transparent, had become cloudy green-blue, indicating rapid corrosion. [Explanation of symbols]

[0074] 10 Liquid desiccant air conditioner 20 Processing Machine 21 Air intake 22 Exhaust port 23 Humidity Control Liquid 24 Gas-liquid contactor 25 Humidity control liquid outlet 26 Humidity control liquid supply port 30 Recycler 31 Air intake 32 Exhaust port 33 Humidity Control Liquid 34 Gas-liquid contactor 35 Humidity control liquid outlet 36 Humidity control liquid supply port 41 Heat exchanger 42 Heat Pump

Claims

1. The composition contains lithium chloride, water, a water-soluble rust inhibitor, and an ionic liquid. The lithium chloride is contained in an amount of 11% by mass to 40% by mass based on the total mass of the humidity-conditioning liquid, the water-soluble rust inhibitor is contained in an amount ranging from 0.02 mol / L to 0.8 mol / L based on the total volume of the humidity-conditioning liquid; The water-soluble rust inhibitor is benzotriazole, The ionic liquid is a humidity-conditioning liquid containing imidazolium.

2. The humidity-conditioning liquid according to claim 1, wherein the water-soluble rust inhibitor is dissolved at a temperature at which the humidity-conditioning liquid is used.

3. The humidity-conditioning liquid according to claim 1 , wherein the ionic liquid has water absorption and release properties.

4. preparing an additive by mixing an ionic liquid aqueous solution containing an ionic liquid and water with a water-soluble rust inhibitor; mixing the additive with an aqueous lithium chloride solution containing lithium chloride and water; A method for producing a humidity-conditioning liquid comprising:

5. 5. The method for producing a humidity-conditioning liquid according to claim 4, wherein the additive is mixed in an amount ranging from 1% by mass to 45% by mass based on the total mass of the humidity-conditioning liquid.

6. 5. The method for producing a humidity control liquid according to claim 4, wherein the lithium chloride aqueous solution contains the lithium chloride in a range of 20 mass % to 40 mass % based on the total mass of the lithium chloride aqueous solution.

7. A humidity control method for controlling humidity using the humidity control liquid according to any one of claims 1 to 3.

8. A humidity control device comprising a humidity control section that brings the humidity control liquid according to any one of claims 1 to 3 into contact with air.

9. The humidity control device according to claim 8 , wherein at least a part of the portion that comes into contact with the humidity control liquid contains copper.

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