Zeolite separation material and method for separating ethyleneamines from water

Abstract

To provide a zeolite separation material and a method for stably separating an ethylene amine from water in an aqueous solution, which contains the ethylene amines of 10-90 wt.%.SOLUTION: A zeolite separation material is used to separate an ethylene amine from water in an aqueous solution, which contains the ethylene amines of 10-90 wt.%. The zeolite separation material contains a zeolite with the molar ratio SiO2 / Al2O3 of 2-40 and a total metal ion exchange rate of 90% or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a zeolite separation material and a method for separating ethyleneamines from water, and more particularly to a zeolite separation material that separates ethyleneamines from water from an aqueous solution containing ethyleneamines, and a method for separating ethyleneamines from water using the zeolite separation material. [Background technology]

[0002] The EDC process is a method for producing ethyleneamines. This process involves reacting ethylene dichloride with aqueous ammonia at high temperature and pressure to obtain an aqueous solution of ethyleneamine hydrochloride. To separate the ethyleneamines from this reaction solution, sodium hydroxide is added to the reaction solution to metathesize the ethyleneamine hydrochloride and ammonium chloride, followed by heating to recover the free ammonia, which is then evaporated and concentrated to crystallize and separate the sodium chloride, yielding the ethyleneamines.

[0003] However, this method has problems such as the need to evaporate and separate the large amount of water used in the reaction, requiring a large amount of energy, and the need for complex and expensive equipment and sophisticated operations to efficiently separate sodium chloride from ethyleneamines.

[0004] As a method for solving such problems, Patent Documents 1, 2, and 3 have investigated and proposed a method of extracting and separating the compound using an organic solvent having a ketone group, an organic solvent containing a carboxylic acid compound or an alkylphosphate compound, or an alcohol in the presence of ammonia.

[0005] On the other hand, as a method for removing water from organic amines containing trace amounts of water, Patent Document 4 has been studied and proposed, in which zeolite is used to simply remove water on the order of several hundred ppm.

[0006] Furthermore, methods for separating amine compounds using zeolite membranes have also been investigated. Patent Document 5 claims a zeolite separation membrane for separating amine compounds, characterized by containing MFI zeolite. An example has been reported in which 50 mol % ethylenediamine and water were concentrated to 65 to 88 mol % by pervaporation using an MFI zeolite membrane crystallized at a SiO2 / Al2O3 molar ratio of 50 to ∞.

[0007] Patent Document 6 claims a method for dehydrating and concentrating hydrous ethyleneamine, which comprises contacting one of the two surfaces of a separation membrane made of a porous support, at least one surface of which is coated with a hydrophilic zeolite membrane, with hydrous ethyleneamine, and applying a pressure difference so that the surface side contacted with the hydrous ethyleneamine is higher than the other side.

[0008] An example has been reported in which only water permeated a MOR-type zeolite membrane crystallized with a SiO2 / Al2O3 molar ratio of 240 using a pervaporation method with 17.5 mol% ethylenediamine in water.

[0009] Patent Document 7 also cites the problem that separation of water from alkaline hydrous organic compounds has been considered difficult because the Si-O bond sites in the zeolite framework are easily hydrolyzed in alkaline solutions, destroying the framework and dissolving the zeolite. It claims a method for separating water from alkaline hydrous organic compounds using a separation membrane from hydrous organic compounds at pH 8 to 13, characterized in that the separation membrane uses a zeolite membrane and the zeolite constituting the zeolite membrane is a CHA-type zeolite with a SiO2 / Al2O3 molar ratio of 5 to 40. Examples of organic compounds mentioned include carboxylic acids, organic acids, alcohols, ketones, aldehydes, ethers, nitrogen-containing organic compounds (N-containing organic compounds), and esters, but the only example of an organic compound is ethanol.

[0010] Another problem with zeolite membranes has been pointed out: their water resistance. For example, Non-Patent Document 1 states that LTA zeolite membranes cannot be used under conditions with a high water content, and that there is a strong demand for the development of zeolite membranes with excellent hydrothermal stability. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Japanese Patent Application Publication No. 58-213738 [Patent Document 2] Japanese Patent Application Publication No. 59-20252 [Patent Document 3] Japanese Patent Application Publication No. 59-175457 [Patent Document 4] Japanese Patent Application Publication No. 7-278064 [Patent Document 5] Japanese Patent Application Laid-Open No. 2015-150527 [Patent Document 6] Japanese Patent Application Laid-Open No. 2017-18848 [Patent Document 7] Japanese Patent Application Laid-Open No. 2018-161647 [Non-patent literature]

[0012] [Non-Patent Document 1] Research report from the Grant-in-Aid for Scientific Research (Institution number: 15401, Project number: 25620151) Summary of the Invention [Problem to be solved by the invention]

[0013] As described above, there have been few reports of separation materials and separation methods for separating ethyleneamines and water from an aqueous solution containing ethyleneamines, which do not require a large amount of energy or organic solvents. In particular, there have been no reports of methods that enable stable separation using a zeolite separation material that is both alkali-resistant and water-resistant. [Means for solving the problem]

[0014] The present inventors have conducted extensive research into methods for separating ethyleneamines and water from an aqueous solution containing ethyleneamines using various zeolites. As a result, they have completed the present invention. Specifically, the present invention relates to a zeolite separation material, etc., for separating ethyleneamines and water from an aqueous solution containing 10 to 90% by weight of ethyleneamines, characterized by containing a zeolite having an SiO2 / Al2O3 molar ratio of 2 to 40 and a total metal ion exchange rate of 90% or more.

[0015] The present invention will be described in detail below.

[0016] The zeolite contained in the zeolite separation material of the present invention has an SiO2 / Al2O3 molar ratio of 2 to 40. The SiO2 / Al2O3 molar ratio of the zeolite is not less than 2. An SiO2 / Al2O3 molar ratio of more than 40 is unacceptable because it reduces alkali resistance. As the SiO2 / Al2O3 molar ratio increases, alkali resistance decreases and water resistance increases. Therefore, in order to have both alkali resistance and water resistance, the SiO2 / Al2O3 molar ratio is preferably 2 to 20, more preferably 2 to 10, even more preferably 2 to 6, and most preferably 2 to 3.

[0017] The zeolite contained in the zeolite separation material of the present invention must have a total metal ion exchange rate of 90% or more. The metal ion exchange rate can be expressed as the number of equivalents of metal ions relative to the number of Al moles in the zeolite (moles × equivalents). A total exchange rate of less than 90% is undesirable because hydrogen ions chemically adsorb to ethyleneamines, making it impossible to selectively adsorb water, and a large amount of energy is required to desorb the adsorbed ethyleneamines. The total exchange rate is preferably 95% or more, and more preferably 98% or more. The total exchange rate is usually 120% or less. Examples of metal ions include alkali metal ions such as Li, Na, K, and Rb; alkaline earth metal ions such as Mg, Ca, and Sr; transition metal ions such as Fe, Co, and Ni; and rare earth ions such as La, Ce, and Pr. Among these metal ions, Na, K, Mg, Ca, La, and Ce are preferred from the standpoints of cost and water resistance, with Na, K, Ca, and La being particularly preferred, and Na, Ca, and La being most preferred. The metal ion may be of one type or a composite of two or more types.

[0018] The zeolite separation material of the present invention may be in any form of powder, molded body (beads or pellets), or membrane.

[0019] The zeolite contained in the zeolite separation material of the present invention may have, for example, an FAU structure, an LTA structure, a CHA structure, or an MFI structure. Among these, the FAU structure is preferred because it has a large volume accessible to water. Here, the XX structure is a structure defined by the International Zeolite Association (IZA) as a three-letter code.

[0020] When the zeolite separation material of the present invention is used as a molded body, it may contain additives such as cellulose, alcohol, lignin, starch, guar gum, etc., to act as binders such as clay, alumina, silica, etc. The additives may be used alone or in combination. There is no limit to the number of parts added.

[0021] The ethyleneamines to be separated by the zeolite separation material of the present invention refer to, for example, linear and cyclic ethyleneamines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, aminoethylpiperazine, and piperazine.

[0022] The ethyleneamines may be, for example, ethyleneamine alone or a mixture of ethylenediamine, diethylenetriamine, triethylenetetramine, etc. The concentration of each ethyleneamine component is not particularly limited.

[0023] The method of the present invention targets an aqueous solution containing 10 to 90% by weight of ethyleneamines. There are no particular limitations on the coexisting components other than ethyleneamines and water. Examples of the coexisting components include NaCl.

[0024] The method of the present invention targets 10 to 90% by weight of ethyleneamines. Less than 10% by weight is cost-disadvantageous as a method for producing ethyleneamines. If it exceeds 90% by weight, the amount of dehydration is small, so zeolite that does not have both alkali resistance and water resistance can be discarded without being reused. The ethyleneamines are preferably 30 to 70% by weight, more preferably 40 to 60% by weight.

[0025] The pH at room temperature of an aqueous solution containing 10 to 90% by weight of ethyleneamines is at least 13 or higher, and usually 14 or higher. Therefore, zeolites need to be alkali-resistant.

[0026] Examples of a method for contacting ethyleneamines with water from an aqueous solution containing 10 to 90% by weight of ethyleneamines include a batch method and a flow method.

[0027] The contact temperature can be, for example, from room temperature to 200° C., and in order to reduce heat loss from the previous step, 100 to 200° C. is preferred, and 120 to 160° C. is particularly preferred. There are no particular limitations on the contact time.

[0028] The zeolite separation material of the present invention can stably separate ethyleneamines and water by using zeolite that is both alkali-resistant and water-resistant. Continuous use and repeated reuse are possible by using an appropriate zeolite regeneration method as needed. An example of a zeolite regeneration method is heat treatment to desorb the adsorbed water. An example of the heat treatment is a temperature of 350°C or higher for one hour or more. [Effects of the Invention]

[0029] According to the present invention, it is possible to provide a zeolite separation material and a separation method that can stably separate ethyleneamines and water from an aqueous solution containing ethyleneamines. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 10 is a graph showing the change in permeability coefficient over time in a dehydration test of the membrane of Example 11. [Figure 2] FIG. 10 is a graph showing the change in separation coefficient over time in a dehydration test of the membrane of Example 11. [Figure 3] FIG. 10 is a graph showing the change in permeability coefficient over time in a dehydration test of the membrane of Example 12. [Figure 4] FIG. 10 is a graph showing the change in separation coefficient over time in a dehydration test of the membrane of Example 12. [Example]

[0031] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these examples. The measurement methods used in the examples and comparative examples are as follows.

[0032] <Ethyleneamine aqueous solution immersion test 1> The water adsorption selectivity and alkali resistance of the zeolite were tested using 50 wt % ethyleneamine and 50 wt % water (pH measured by a pH electrode: 14.4; room temperature).

[0033] 2 g of zeolite powder and 50 g of a 50 wt% aqueous ethyleneamine solution were placed in an 80 ml stainless steel container, mixed uniformly, and then sealed. The stainless steel container was placed in a rotary autoclave (hydrothermal synthesis reactor) and kept rotating at 140°C for 48 hours.

[0034] After cooling, the container was removed, and after solid-liquid separation using filter paper, the solid content was washed with 200 g of pure water. The washed filter cake was dried overnight at 60 ° C in a dryer to obtain zeolite after the immersion test.

[0035] After the immersion test, the zeolite was subjected to thermal analysis to evaluate its water adsorption selectivity, and powder X-ray diffraction measurements were performed on the zeolite before and after the immersion test to evaluate its alkali resistance.

[0036] <Ethyleneamine aqueous solution immersion test 2> The same test as in Ethyleneamine Aqueous Solution Immersion Test 1 was carried out, except that the sample was placed in a rotary autoclave (hydrothermal synthesis reactor) and kept in a rotating state at 160°C for 4 months.

[0037] <Thermal analysis> Measurements were taken using a thermal analyzer (product name: TG / DTA6300, manufactured by SII Nano Technology) at a temperature increase rate of 10°C / min under air flow. The weight loss from room temperature to 200°C was evaluated as the amount of water adsorption, and the weight loss from 200°C to 600°C was evaluated as the amount of ethyleneamine adsorption.

[0038] <Water adsorption selectivity> The water adsorption selectivity was calculated from the water adsorption amount and ethyleneamine adsorption amount evaluated by thermal analysis using the following formula.

[0039] Water adsorption selectivity = water adsorption amount / (water adsorption amount + ethyleneamine adsorption amount) <Powder X-ray diffraction> Powder X-ray diffraction measurements of the samples were carried out using a powder X-ray diffractometer (product name: Ultima IV, manufactured by Rigaku). CuKα radiation (λ = 1.5405 Å) was used as the radiation source, and the measurement range was 2θ = 5° to 43°.

[0040] The powder X-ray diffraction patterns before and after the ethyleneamine aqueous solution immersion test or before and after the hot steam resistance test were compared, and the crystal retention rate was calculated from a predetermined peak intensity ratio.

[0041] <Heat steam resistance test 1> 0.5 g of zeolite powder was placed in a crucible, which was then placed in a 700 ml stainless steel container. 140 g of pure water was placed in the bottom of the stainless steel container, and the container was sealed to prevent contact between the zeolite powder and liquid water (zeolite powder can come into contact with water vapor at the vapor pressure of a specified temperature). The stainless steel container was placed in a dryer and left stationary at 140°C for 48 hours.

[0042] The container was removed after cooling, and the zeolite was subjected to a hot steam resistance test.

[0043] The zeolite was subjected to powder X-ray diffraction measurement before and after the hot steam resistance test to evaluate its hot steam resistance.

[0044] <Heat steam resistance test 2> The same test as in Hot Steam Resistance Test 1 was carried out, except that the stainless steel container was placed in a dryer and kept stationary at 160°C for 4 months.

[0045] <X-ray diffraction of film> X-ray diffraction measurements of the film surface were carried out using an X-ray diffractometer (product name: SmartLab, manufactured by Rigaku Corporation). CuKα radiation (λ=1.5405 Å) was used as the radiation source, and the measurement range was 2θ=5° to 45°.

[0046] <Film composition analysis> The composition of the film surface was analyzed using an EDS analyzer attached to a scanning electron microscope (product name: JSM-IT200, manufactured by JEOL Ltd.).

[0047] <Membrane dehydration test> A dehydration test was carried out under the following conditions using a membrane evaluation device.

[0048] Method: PV evaluation (pervaporation evaluation) Evaluation liquid: ethyleneamine aqueous solution (ethyleneamine 50% by weight, water 50% by weight) Temperature: 130℃ Flow rate: 5L / min Vacuum level: <2kPa Effective membrane area: 0.0019m 2 Evaluation time: 30 hours The evaluation items were the permeability coefficient and separation coefficient, which were calculated as follows:

[0049] Permeability coefficient (kg / m 2 / h / kPa)=permeation flow rate (kg / m 2 / h) / pressure (kPa) Separation factor (-) = [(100 - permeate concentration (wt%)) / permeate concentration (wt%)] / [(100 - feed concentration (wt%)) / feed concentration (wt%)] Example 1 42g of sodium silicate, 55g of sodium aluminate, 2g of 48% caustic, and 120ml of water were mixed in a ratio of Si / Al2 = 2.0 (mol / mol), and crystallized at 90°C for 6 hours to obtain a slurry containing NaA-type zeolite. The crystallized slurry was filtered, washed, and dried to obtain NaA-type zeolite powder (zeolite separation material).

[0050] A portion of the zeolite powder was dissolved in a mixed solution of nitric acid and hydrofluoric acid, and the composition was analyzed by ICP-AES, which revealed that SiO2 / Al2O3=2.0, Na / Al=100%.

[0051] Example 2 56g of sodium silicate, 50g of sodium aluminate, 7g of 48% caustic, and 120ml of water were mixed in a ratio of Si / Al2 = 3.0 (mol / mol), and crystallized at 90°C for 6 hours to obtain a slurry containing NaX zeolite. The crystallized slurry was filtered, washed, and dried to obtain NaX zeolite powder (zeolite separation material).

[0052] A portion of the zeolite powder was dissolved in a mixed solution of nitric acid and hydrofluoric acid, and the composition was analyzed by ICP-AES, which revealed that SiO2 / Al2O3=2.5, Na / Al=100%.

[0053] Example 3 27g of sodium silicate, 34g of sodium aluminate, 1g of 48% caustic, and 138ml of water were mixed in a ratio of Si / Al2 = 10 (mol / mol) and crystallized at 90°C for 30 hours to obtain a slurry containing NaY-type zeolite. The crystallized slurry was filtered, washed, and dried to obtain NaY-type zeolite powder (zeolite separation material).

[0054] A portion of the zeolite powder was dissolved in a mixed solution of nitric acid and hydrofluoric acid, and the composition was analyzed by ICP-AES, which revealed that SiO2 / Al2O3=5.7, Na / Al=100%.

[0055] Example 4 10 g of ZSM-5 zeolite powder (product name: HSZ (registered trademark)-820NHA, manufactured by Tosoh Corporation) was added to 100 g of a 10% aqueous NaCl solution and stirred at room temperature for 1 hour. The resulting zeolite slurry was filtered using a funnel and a filter bottle, and then washed with 200 g of pure water to obtain a partially Na-exchanged ZSM-5 zeolite powder.

[0056] The obtained partially Na-exchanged ZSM-5 type zeolite powder was further treated with 100 g of 10% NaCl aqueous solution, and the above procedure (addition-stirring-filtration-washing) was repeated twice to obtain completely Na-exchanged ZSM-5 type zeolite powder (zeolite separation material).

[0057] A portion of the zeolite powder was dissolved in a mixed solution of nitric acid and hydrofluoric acid, and the composition was analyzed by ICP-AES, revealing that SiO2 / Al2O3=24, Na / Al=100%.

[0058] Example 5 Using the zeolite separation material (NaA-type zeolite powder (LTA structure, SiO2 / Al2O3=2.0, Na / Al=100% → total metal ion exchange rate=100%) obtained in Example 1, ethyleneamine aqueous solution immersion tests 1 and 2 and hot steam resistance tests 1 and 2 were carried out. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=24.0°. The results are shown in Tables 1 and 2.

[0059] [Table 1]

[0060] [Table 2]

[0061] Example 6 Using the zeolite separation material (NaX-type zeolite powder (FAU structure, SiO2 / Al2O3=2.5, Na / Al=100% → total metal ion exchange rate=100%) obtained in Example 2, ethyleneamine aqueous solution immersion tests 1 and 2 and hot steam resistance tests 1 and 2 were carried out. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=23.3°. The results are shown in Tables 1 and 2.

[0062] Example 7 Using the zeolite separation material (NaY-type zeolite powder (FAU structure, SiO2 / Al2O3=5.7, Na / Al=100% → total metal ion exchange rate=100%) obtained in Example 3, ethyleneamine aqueous solution immersion tests 1 and 2 and hot steam resistance tests 1 and 2 were carried out. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=23.6°. The results are shown in Tables 1 and 2.

[0063] Example 8 The zeolite separation material (ZSM-5 type zeolite powder (MFI structure, SiO2 / Al2O3=24, Na / Al=100% → total metal ion exchange rate=100%) obtained in Example 4 was used to conduct ethyleneamine aqueous solution immersion test 1 and hot steam resistance test 1. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=23.0°. The results are shown in Tables 1 and 2.

[0064] Example 9 108g of sodium silicate, 54g of sodium aluminate, 13g of 99% caustic, 36g of 48% caustic potassium, and 13ml of water were mixed in a ratio of Si / Al2 = 2.0 (mol / mol) and crystallized at 70°C for 8 hours to obtain a slurry containing (Na,K)LSX zeolite. The crystallized slurry was filtered, washed, and dried to obtain (Na,K)LSX zeolite powder (zeolite separation material).

[0065] Example 10 Using the zeolite separation material ((Na,K)LSX type zeolite powder (FAU structure, SiO2 / Al2O3=2.0, Na / Al=72%, K / Al=28% → total metal ion exchange rate=100%) obtained in Example 9, ethyleneamine aqueous solution immersion tests 1 and 2 and hot steam resistance tests 1 and 2 were carried out. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=23.3°. The results are shown in Tables 1 and 2.

[0066] Example 11 The NaY-type zeolite membrane was hydrothermally synthesized at 100°C for 2.5 hours using a mullite porous tubular membrane (outer diameter 12 mm) as a support and a reaction solution composition of 25SiO2:1Al2O3:22Na2O:990H2O.

[0067] X-ray diffraction of the obtained film surface confirmed a strong peak due to the FAU structure and a weak peak due to the support. Furthermore, composition analysis of the film surface by EDS analysis revealed that SiO2 / Al2O3 = 4.2, Na / Al = 96%.

[0068] A dehydration test was also conducted on the obtained membrane. Figure 1 shows the time-dependent change in permeability coefficient, and Figure 2 shows the time-dependent change in separation coefficient. Since the permeability coefficient was greater than 0 and the separation coefficient was greater than 1, it was confirmed that water was selectively permeating. Furthermore, the time-dependent change in the permeability coefficient and separation coefficient was small up to 30 hours, confirming that continuous separation for up to 30 hours was possible.

[0069] Example 12 The NaX-type zeolite membrane was hydrothermally synthesized at 80°C for 5 hours using a mullite porous tubular membrane (outer diameter 12 mm) as a support and a reaction solution composition of 8SiO2:1Al2O3:72Na2O:4720H2O.

[0070] X-ray diffraction of the obtained film surface confirmed a strong peak due to the FAU structure and a weak peak due to the support. Furthermore, EDS analysis of the film surface revealed that the SiO2 / Al2O3 ratio was 2.4 and Na / Al ratio was 94%.

[0071] A dehydration test was also conducted on the obtained membrane. Figure 3 shows the time-dependent change in the permeability coefficient, and Figure 4 shows the time-dependent change in the separation coefficient. Since the permeability coefficient was greater than 0 and the separation coefficient was greater than 1, it was confirmed that water was selectively permeating. Furthermore, the time-dependent change in the permeability coefficient and separation coefficient was small up to 30 hours, confirming that continuous separation for up to 30 hours was possible.

[0072] Example 13 The zeolite separation material (NaX-type zeolite powder (FAU structure, SiO2 / Al2O3=2.5, Na / Al=100% → total metal ion exchange rate=100%) obtained in Example 2 was subjected to calcium ion exchange using a calcium chloride aqueous solution, followed by washing and drying to obtain CaNaX-type zeolite powder (FAU structure, SiO2 / Al2O3=2.5, 2Ca / Al=88%, Na / Al=9% → total metal ion exchange rate=97%). Using the obtained CaNaX-type zeolite powder separation material, ethyleneamine aqueous solution immersion tests 1 and 2 and hot steam resistance tests 1 and 2 were performed. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=23.3°. The results are shown in Tables 1 and 2.

[0073] Example 14 The zeolite separation material (NaX-type zeolite powder (FAU structure, SiO2 / Al2O3=2.5, Na / Al=100% → total metal ion exchange rate=100%) obtained in Example 2 was subjected to lanthanum ion exchange using a lanthanum chloride aqueous solution, followed by washing and drying to obtain LaNaX-type zeolite powder (FAU structure, SiO2 / Al2O3=2.5, 3La / Al=36%, Na / Al=55% → total metal ion exchange rate=91%). Using the obtained LaNaX-type zeolite powder separation material, ethyleneamine aqueous solution immersion tests 1 and 2 and hot steam resistance tests 1 and 2 were performed. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=23.3°. The results are shown in Tables 1 and 2.

[0074] Example 15 The zeolite separation material (NaY-type zeolite powder (FAU structure, SiO2 / Al2O3=5.7, Na / Al=100% → total metal ion exchange rate=100%) obtained in Example 3 was subjected to calcium ion exchange using a calcium chloride aqueous solution, followed by washing and drying to obtain CaNaY-type zeolite powder (FAU structure, SiO2 / Al2O3=5.7, 2Ca / Al=86%, Na / Al=17% → total metal ion exchange rate=103%). Using the resulting CaNaY-type zeolite powder separation material, ethyleneamine aqueous solution immersion tests 1 and 2 and hot steam resistance tests 1 and 2 were performed. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=23.6°. The results are shown in Tables 1 and 2.

[0075] Manufacturing Example 1 The NaY zeolite powder obtained in Example 3 was repeatedly subjected to acid treatment and heat treatment to obtain USY zeolite powder (SiO2 / Al2O3=115, H / Al≈100% → total metal ion exchange rate=0%).

[0076] Manufacturing Example 2 43g of precipitated silica, 22g of 40% tetrapropylammonium hydroxide, and 15ml of water were mixed and crystallized at 150℃ for 48 hours (Si / Al2 = 3000 (mol / mol)), to obtain a slurry containing silicalite powder. The crystallized slurry was filtered, washed, dried, and calcined to obtain silicalite powder (SiO2 / Al2O3 = 2000, H / Al ≒ 100% → total metal ion exchange rate = 0%).

[0077] Manufacturing Example 3 33g of silica alumina gel, 4g of 48% caustic, 2g of 48% caustic potassium, 23g of 25% 1-adamantanammonium hydroxide, and 19ml of water were mixed in a ratio of Si / Al2 = 18 (mol / mol) and crystallized at 150°C for 72 hours to obtain a slurry containing SSZ-13 type zeolite. The crystallized slurry was filtered, washed, dried, calcined, acid-treated, washed, and dried to obtain SSZ-13 type zeolite powder (SiO2 / Al2O3 = 14, H / Al ≒ 100% → total metal ion exchange rate = 0%).

[0078] Production Example 4 33g of silica alumina gel, 3g of 48% caustic, 2g of 48% caustic potassium, 23g of 25% 1-adamantanammonium hydroxide, and 19ml of water were mixed in a ratio of Si / Al2 = 22 (mol / mol) and crystallized at 150°C for 72 hours to obtain a slurry containing SSZ-13 type zeolite. The crystallized slurry was filtered, washed, dried, calcined, acid-treated, washed, and dried to obtain SSZ-13 type zeolite powder (SiO2 / Al2O3 = 17, H / Al ≒ 100% → total metal ion exchange rate = 0%).

[0079] Comparative Example 1 Using the zeolite separation material (USY-type zeolite powder (FAU structure, SiO2 / Al2O3=115, H / Al≈100% → total metal ion exchange rate=0%) obtained in Production Example 1, an ethyleneamine aqueous solution immersion test 1 and a hot steam resistance test 1 were conducted. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=23.8°. The results are shown in Tables 1 and 2.

[0080] Comparative Example 2 Using the zeolite separation material (silicalite powder (MFI structure, SiO2 / Al2O3 = 2000, H / Al ≈ 100% → total metal ion exchange rate = 0%) obtained in Production Example 2, an ethyleneamine aqueous solution immersion test 1 and a hot steam resistance test 1 were conducted. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ = 23.1°. The results are shown in Tables 1 and 2.

[0081] Comparative Example 3 Using the zeolite separation material (SSZ-13 type zeolite powder (CHA structure, SiO2 / Al2O3=14, H / Al≈100% → total metal ion exchange rate=0%) obtained in Production Example 3, an ethyleneamine aqueous solution immersion test 1 and a hot steam resistance test 1 were conducted. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=20.7°. The results are shown in Tables 1 and 2.

[0082] Comparative Example 4 Using the zeolite separation material (SSZ-13 type zeolite powder (CHA structure, SiO2 / Al2O3=17, H / Al≈100% → total metal ion exchange rate=0%) obtained in Production Example 4, an ethyleneamine aqueous solution immersion test 1 and a hot steam resistance test 1 were conducted. In the evaluation by powder X-ray diffraction, the crystal retention rate was calculated using the peak intensity at 2θ=20.7°. The results are shown in Tables 1 and 2.

[0083] According to Tables 1 and 2, Examples 5 to 8 and 10, which used zeolites with SiO2 / Al2O3 molar ratios of 2 to 40 and a total metal ion exchange rate of 90% or more, exhibited high water adsorption selectivity and crystal retention in the ethyleneamine aqueous solution immersion test, and high crystal retention in the hot steam resistance test, making them usable as separation materials and separation methods that perform stable separation.On the other hand, Comparative Examples 1 to 4 had low evaluation values ​​and could not be used as separation materials or separation methods that perform stable separation. [Industrial Applicability]

[0084] The zeolite separation material of the present invention can be used as a separation material and a separation method for stably separating ethyleneamines and water from an aqueous solution containing 10 to 90% by weight of ethyleneamines.

Claims

1. SiO for separating ethyleneamines and water from an aqueous solution containing 10 to 90% by weight of ethyleneamines ２ / Al ２ O ３ A zeolite separation material containing zeolite having a molar ratio of 2 to 40 and a total metal ion exchange rate of 90% or more.

2. 2. The zeolite separation material according to claim 1, wherein the zeolite has an FAU structure.

3. A method for separating ethyleneamines and water from an aqueous solution containing 10 to 90% by weight of ethyleneamines, using the zeolite separation material according to claim 1 or 2.

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