In-situ regeneration of a resin catalyst

Abstract

The present invention provides a method for regenerating a resin catalyst for the hydration of an enal to produce a hydroxy aldehyde, the method comprising the steps of: (1) eluting the deactivated resin catalyst with a first solvent at a first temperature; (2) contacting the resin catalyst with a mixed solution comprising an acid functional group-containing substance and a basic catalyst at a second temperature; and (3) acidifying the resin catalyst with an acid solution containing metal ions. The present invention also provides a resin catalyst regenerated by the above method. Furthermore, the present invention provides a method for the hydration of an enal to produce a hydroxy aldehyde using a resin catalyst, wherein the catalyst is regenerated in situ by the above method.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, in particular to an in-situ regeneration method of a resin catalyst for preparing hydroxy aldehydes by hydrating alkenal. Background Art

[0002] Polytrimethylene terephthalate (PTT) is a polyester material with excellent performance. It combines the softness and color fastness of nylon, the fluffiness of acrylic, the stain resistance of polyester, and has high resilience. It has been rated as one of the "Six New Petrochemical Products" of the new century. 1,3-Propanediol (1,3-PDO) is a key raw material for the production of polytrimethylene terephthalate (PTT). However, the preparation technology of 1,3-PDO is relatively difficult and has high technical barriers. A known preparation method for 1,3-PDO is the hydration hydrogenation method of acrolein, which has mild reaction conditions, low equipment requirements, a wide source of raw materials, and is suitable for industrial production.

[0003] The non-patent document "Research and Development of New Technologies for the Synthesis of 1,3-Propanediol by Acrolein Hydration and Hydrogenation" (Tang Yong, East China University of Science and Technology, 2014) reports on resin catalysts using aminocarboxylic acid or aminophosphoric acid as active functional groups. Due to the good acid-base synergy, this resin catalyst can effectively reduce the activation energy of the main acrolein hydration reaction, achieving high conversion rate and reaction selectivity. However, during the long-term acrolein hydration reaction, the catalytic activity of this resin catalyst showed a downward trend as the reaction progressed. The catalyst was deactivated after 2000 hours of evaluation, and the conversion rate and selectivity decreased, making it unable to meet the requirements of industrial implementation.

[0004] Therefore, it is very important to explore the regeneration method of the resin catalyst and improve the service life of the catalyst for the industrial production of 1,3-PDO by the hydration hydrogenation of acrolein.

[0005] The non-patent literature "Study on the Deactivation Mechanism of Acrolein Hydration Catalyst B101 and Improving Its Stability" (Zhou Liuyin, Jiang Qizhong, Zhang Chunlei, etc., Journal of Chemical Engineering of Colleges and Universities, 2007, 21(1):5.) reported that the reasons for the deactivation of acrolein hydration catalyst include the following three points: First, the surface active group H + First, the number of active centers is reduced due to replacement by metal ions such as calcium and magnesium ions in the aqueous solution, resulting in a decrease in activity. Second, the surface active centers are covered by polymers generated during the reaction, leading to a decrease in catalytic activity. Third, the loss of surface active functional groups destroys the catalyst structure, resulting in a decrease in acid exchange capacity. The deactivated catalyst was reactivated and regenerated using 1 mol / L hydrochloric acid, but the deactivated catalyst could not be restored to its initial activity.

[0006] Patent document CN201510984141 discloses a method for regenerating hydrogen-type chelating resin. This method involves pouring an inorganic acid solution downstream from the top of a reaction column and circulating it for 1 to 1.5 hours. The inorganic acid then reacts with the D403 chelating resin within the column, effectively replacing divalent and trivalent ions in the condensate. This method is simple and easy to implement, effectively reducing wastewater discharge and acid and alkali usage.

[0007] Patent document CN201710307910 discloses a method for regenerating a chelating resin, which is regenerated by elution with a 5% acetic acid solution to restore the acidic active sites on the resin catalyst.

[0008] As mentioned above, existing technologies often regenerate resin catalysts through acid washing, which can restore hydrogen ions exchanged for metal ions such as sodium, magnesium, calcium, and aluminum. However, it cannot restore deactivation caused by functional group loss and pore blockage. The loss of active functional groups is an irreversible process, and acid or solvent washing alone cannot replenish active sites and restore the catalyst to fresh levels.

[0009] Therefore, there is an urgent need in the art for a regeneration method of a resin catalyst that can overcome the above-mentioned defects. Summary of the Invention

[0010] The object of the present invention is to provide an in-situ regeneration method for a resin catalyst, which can not only restore the catalyst deactivation caused by metal ion exchange and pore blocking, but also replenish active sites in situ, so that the reaction effect and service life of the regenerated catalyst reach the level of a fresh catalyst.

[0011] The present invention also aims to provide an in-situ regeneration method for a resin catalyst for preparing 3-hydroxypropionaldehyde by acrolein hydration, which can regenerate the deactivated catalyst to the level of a fresh catalyst, thereby increasing the service life of the catalyst, reducing the frequency of catalyst replacement, and lowering industrial costs.

[0012] In order to achieve this object, the present invention provides the following method:

[0013] A method for regenerating a resin catalyst, wherein the resin catalyst is a resin catalyst for preparing hydroxy aldehydes by hydrating alkenal, characterized in that the method comprises the following steps:

[0014] (1) eluting the deactivated resin catalyst with a first solvent at a first temperature;

[0015] (2) contacting a mixed solution of a substance containing an acidic functional group and a basic catalyst with a resin catalyst at a second temperature, wherein the substance containing an acidic functional group may be a halogenated acid or a halogenated ester, preferably a halogenated carboxylic acid, a halogenated carboxylic ester, and a halogenated phosphoric acid, more preferably a chlorocarboxylic acid, a chlorocarboxylic ester, and a chlorophosphoric acid;

[0016] (3) Acidifying the resin catalyst with an acidic solution containing metal ions.

[0017] Preferably, the deactivated resin catalyst is a chelate resin catalyst of the type of aminocarboxylic acid or aminophosphoric acid, which has amino groups on its surface. Preferably, the amino group content accounts for 2-8%.

[0018] Preferably, step (1) is carried out in a fixed-bed continuous flow reactor, and the first solvent is pumped into the catalyst bed and circulated for a first time.

[0019] Preferably, in step (1), the first temperature is 10-200°C. The first temperature is more preferably 10-70°C, and still more preferably 20-50°C.

[0020] Preferably, in step (1), the first time is 1-72 hours, more preferably 2-48 hours, and still more preferably 12-48 hours.

[0021] Preferably, in step (1), the first solvent is an organic solvent. Specifically, the first solvent can be selected from a combination of one or more of alkyl halides, alcohols, nitriles, aromatic hydrocarbons, phenols, amides, esters, and can be selected from a combination of one or more of dichloromethane, dichloroethane, methanol, ethanol, acetonitrile, toluene, benzene, ethylbenzene, PEG-200, cyclohexane, cyclohexanol, N,N-dimethylformamide, or dimethyl sulfoxide, preferably dichloroethane, methanol, ethanol, or N,N-dimethylformamide.

[0022] Preferably, in step (1), the mass ratio of the resin catalyst to the first solvent is 1:2-1:100. The mass ratio of the resin catalyst to the first solvent is more preferably 1:5-1:75, and still more preferably 1:10-1:50.

[0023] Preferably, step (2) is carried out in a fixed-bed continuous flow reactor, and the mixed solution passes through the resin catalyst layer in the fixed-bed continuous flow reactor from top to bottom and circulates for the second time.

[0024] Preferably, in step (2), the second temperature is 10-200°C. More preferably, the second temperature is 30-100°C.

[0025] Preferably, in step (2), the second time is 1-48 hours, more preferably 2-24 hours, and most preferably about 12 hours.

[0026] Preferably, in step (2), the substance containing an acidic functional group is selected from one or more combinations of chloroacetic acid, chloroformic acid, chloropropionic acid, methyl chloroacetate, methyl chloropropionate, chloromethylsulfonic acid, chloromethylphosphoric acid, etc., preferably chloroacetic acid, chloropropionic acid, methyl chloroacetate, chloromethylphosphoric acid or a combination thereof.

[0027] Preferably, in step (2), the alkaline catalyst is selected from one or more combinations of sodium carbonate, sodium hydroxide, potassium carbonate, potassium hydroxide, triethylamine, sodium methoxide, potassium ethoxide, potassium tert-butoxide, ethylenediamine, etc., preferably sodium carbonate, potassium carbonate, triethylamine, potassium hydroxide or a combination thereof.

[0028] Preferably, in step (2), the solvent of the mixed solution is an inorganic solvent or an organic solvent, which is selected from one or more combinations of water, ethanol, methanol, acetonitrile, dichloroethane, etc., and water is most preferred.

[0029] Preferably, in step (2), the molar ratio of the amine-containing group to the acidic functional group-containing substance in the resin treated in step (1) is 1:1-1:10. The molar ratio is more preferably 1:2-1:8, and still more preferably 1:2-1:6.

[0030] Preferably, in step (2), the molar ratio of the amine-containing groups in the resin treated in step (1) to the alkaline catalyst is 1:1-1:20. The molar ratio is more preferably 1:2-1:15, and still more preferably 1:2-1:8.

[0031] Preferably, in step (2), the molar ratio of the substance containing an acidic functional group to the solvent is 1:1-1:100. The molar ratio is more preferably 1:2-1:90, and still more preferably 1:10-1:70.

[0032] Preferably, step (3) is carried out in a fixed-bed continuous flow reactor, and the acidification lasts for a third time.

[0033] Preferably, in step (3), the acidic solution is selected from a combination of one or more of hydrochloric acid, nitric acid, phosphoric acid, etc.

[0034] Preferably, in step (3), the acid concentration of the acidic solution is 0.1 mol / L-10 mol / L, more preferably 0.5 mol / L-5 mol / L.

[0035] Preferably, in step (3), the third time is 1-48 hours, more preferably 2-24 hours, and most preferably about 12 hours.

[0036] Preferably, in step (3), the acidic solution passes through the deactivated catalyst at a rate of 1-5 BV / h.

[0037] Preferably, in step (3), the metal ions in the acidic solution containing metal ions are selected from one or more combinations of metal ions such as Cu, Na, Mg, Li, K, Ga, Zn, Ti, Cd, Ca, and Al, preferably Na, Zn, Ti, and Ca.

[0038] Preferably, in step (3), the metal ions account for 10-1000 ppm, preferably 50-500 ppm, relative to the acidic solution.

[0039] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0040] (1) The present invention can regenerate deactivated catalysts to the level of fresh catalysts, thereby increasing the service life of the catalysts, reducing the frequency of catalyst replacement, and lowering industrial costs.

[0041] (2) The catalyst regeneration of the invention adopts the in-situ regeneration method, which is simple and easy to operate, and the required materials are recycled, which can reduce sewage discharge and acid and alkali usage.

[0042] (3) After regeneration, the acid content and active sites are restored, and the catalytic effect of the catalyst is significantly improved. DETAILED DESCRIPTION

[0043] " Scope " disclosed herein is limited in the form of lower limit and upper limit, and given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of special range. The scope limited in this way can be to include end value or not include end value, and can be arbitrarily combined, that is, any lower limit can form a scope with any upper limit combination. For example, if the scope of 60-120 and 80-110 is listed for a particular parameter, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range value 1 and 2 are listed, and if the maximum range value 3,4 and 5 are listed, then the following range can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In this application, unless otherwise specified, the numerical range " ab " represents the abbreviation of any real number combination between a and b, wherein a and b are all real numbers. For example, a numerical range of "0-5" indicates that all real numbers between "0-5" are listed herein, and "0-5" is simply an abbreviation for these numerical combinations. Furthermore, when a parameter is expressed as an integer ≥ 2, this is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0044] In this application, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form a new technical solution.

[0045] In this application, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form a new technical solution.

[0046] In this application, unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0047] In this application, unless otherwise specified, the terms "include" and "comprising" used herein may be open-ended or closed-ended. For example, "include" and "comprising" may mean that other components not listed may also be included or that only the listed components are included.

[0048] In the description of this article, it should be noted that, unless otherwise specified, “above” and “below” are inclusive of the number themselves, and “several” in “one or several” means two or more.

[0049] In the description herein, unless otherwise indicated, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B." More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0050] Herein, unless otherwise specified, percentages (%) or parts refer to percentages or parts by weight relative to the composition.

[0051] Herein, unless otherwise stated, the sum of the contents of the various components in the composition is 100%.

[0052] Herein, unless otherwise stated, the sum of the parts of each component in the composition may be 100 parts by weight.

[0053] In this context, unless otherwise stated, "a combination thereof" means a multi-component mixture of the elements mentioned, for example a mixture of two, three, four and up to the maximum possible multi-component mixture.

[0054] If not specifically stated, the terms "a" and "an" used in this specification mean "at least one".

[0055] Unless otherwise stated, all reactions are carried out at room temperature and pressure.

[0056] The mechanism of the present invention is not clear, but it is believed to be due to the following reasons:

[0057] The carboxyl or phosphate groups on the surface functional groups of the deactivated catalyst have been lost, leaving amino functional groups on the catalyst surface. The present invention adds a substance containing carboxyl or phosphate groups. Under the action of an alkaline catalyst, the amino groups on the surface of the deactivated resin react with the substance containing carboxyl or phosphate groups to remove hydrogen halide, regenerating aminocarboxylic acid or aminophosphoric acid active functional groups, thereby replenishing the functional groups on the surface of the deactivated catalyst and restoring the catalyst to the level of a fresh catalyst.

[0058] Preferably, the deactivated resin catalyst is a chelate resin catalyst of the type of aminocarboxylic acid or aminophosphoric acid, etc. Preferably, the amino content accounts for 2-8%.

[0059] Optionally, before step (1), a pre-cleaning step is further performed to pre-clean away mechanical impurities that may be adsorbed on the resin surface. The pre-cleaning step may use a suitable cleaning solvent, such as but not limited to water.

[0060] Preferably, step (1) is carried out in a fixed-bed continuous flow reactor, and the first solvent is pumped into the catalyst bed and circulated for a first time.

[0061] Preferably, in step (1), the first temperature is 10-200° C. The upper limit of the first temperature is more preferably 150° C., more preferably 120° C., more preferably 100° C., more preferably 90° C., more preferably 80° C., more preferably 70° C., more preferably 65° C., more preferably 60° C., more preferably 55° C., still more preferably 50° C. The lower limit of the first temperature is more preferably 15° C., still more preferably 20° C.

[0062] Preferably, in step (1), the first time is 1-72 hours. The upper limit of the first time is more preferably 60 hours, still more preferably 48 hours. The lower limit of the first time is more preferably 2 hours, more preferably 4 hours, more preferably 6 hours, more preferably 8 hours, more preferably 10 hours, still more preferably 12 hours.

[0063] In step (1), as long as it does not affect the implementation of the present invention, the first solvent can be any solvent, but it is preferably an organic solvent. Specifically, the first solvent can be selected from a combination of one or more of alkyl halides, alcohols, nitriles, aromatic hydrocarbons, phenols, amides, esters, etc., and can be selected from a combination of one or more of dichloromethane, dichloroethane, methanol, ethanol, acetonitrile, toluene, benzene, ethylbenzene, PEG-200, cyclohexane, cyclohexanol, N,N-dimethylformamide or dimethyl sulfoxide, preferably dichloroethane, methanol, ethanol, N,N-dimethylformamide or a combination thereof.

[0064] Preferably, in step (1), the mass ratio of the resin catalyst to the first solvent is 1:2-1:100. The upper limit of the mass ratio of the resin catalyst to the first solvent is more preferably 1:90, more preferably 1:80, more preferably 1:75, more preferably 1:70, more preferably 1:65, more preferably 1:60, more preferably 1:55, and still more preferably 1:50. The lower limit of the mass ratio of the resin catalyst to the first solvent is more preferably 1:3, more preferably 1:4, more preferably 1:5, more preferably 1:6, more preferably 1:7, more preferably 1:8, more preferably 1:9, and still more preferably 1:10.

[0065] Preferably, step (2) is carried out in a fixed-bed continuous flow reactor, and the mixed solution passes through the resin catalyst layer in the fixed-bed continuous flow reactor from top to bottom and circulates for the second time.

[0066] Preferably, in step (2), the second temperature is 10-200° C. The upper limit of the second temperature is more preferably 150° C., more preferably 120° C., more preferably 100° C., more preferably 95° C., more preferably 90° C., still more preferably 85° C. The lower limit of the second temperature is more preferably 20° C., still more preferably 30° C.

[0067] Preferably, in step (2), the second time is 1-48 hours. The upper limit of the second time is more preferably 36 hours, more preferably 24 hours, and still more preferably 18 hours. The lower limit of the second time is more preferably 2 hours, more preferably 4 hours, more preferably 6 hours, more preferably 8 hours, and still more preferably 10 hours. The second time is most preferably about 12 hours.

[0068] In step (2), the described material comprising acidic functional groups can be any material, depends on the kind of the acidic functional groups in the resin catalyst.The material comprising acidic functional groups can be a halogenated acid or a halogenated acid ester, preferably a halogenated carboxylic acid, a halogenated carboxylic ester and a halogenated phosphoric acid, more preferably a chlorocarboxylic acid, a chlorocarboxylic ester and a chlorophosphoric acid.The material comprising acidic functional groups can be selected from one or more combinations such as monochloroacetic acid, chloroformic acid, chloropropionic acid, methyl chloroacetate, methyl chloropropionate, chloromethyl sulfonic acid, chloromethyl phosphoric acid, preferably monochloroacetic acid, chloropropionic acid, methyl chloroacetate, chloromethyl phosphoric acid or its combination.

[0069] In step (2), the alkaline catalyst can be any alkaline substance as long as it can catalyze the reaction between the acidic functional group and the deactivated resin catalyst. The alkaline catalyst can be an inorganic base or an organic base. The alkaline catalyst can be selected from a combination of one or more of sodium carbonate, sodium hydroxide, potassium carbonate, potassium hydroxide, triethylamine, sodium methoxide, potassium ethoxide, potassium tert-butoxide, ethylenediamine, etc., preferably sodium carbonate, potassium carbonate, and triethylamine.

[0070] In step (2), the solvent of the mixed solution can be any solvent as long as it can dissolve or partially dissolve the substance containing the acidic functional group and the basic catalyst. The solvent of the mixed solution can be water or an organic solvent, which can be selected from one or more combinations of water, alcohols such as methanol or ethanol, nitriles such as acetonitrile, halogenated alkanes such as dichloroethane, etc., with water being most preferred.

[0071] Preferably, in step (2), the molar ratio of the amine-containing group to the acidic functional group-containing substance in the resin treated in step (1) is 1:1-1:10. The upper limit of the molar ratio is more preferably 1:9, more preferably 1:8, more preferably 1:7, and still more preferably 1:6. The lower limit of the molar ratio is more preferably 1:2.

[0072] Preferably, in step (2), the molar ratio of the amine-containing groups in the resin treated in step (1) to the alkaline catalyst is 1:1-1:20. The upper limit of the molar ratio is more preferably 1:18, more preferably 1:16, more preferably 1:14, more preferably 1:12, and still more preferably 1:10. The lower limit of the molar ratio is more preferably 1:2.

[0073] Preferably, in step (2), the molar ratio of the substance containing an acidic functional group to the solvent is 1:1-1:100. The upper limit of the molar ratio is more preferably 1:90, more preferably 1:80, and still more preferably 1:70. The lower limit of the molar ratio is more preferably 1:2, more preferably 1:4, more preferably 1:6, more preferably 1:8, and still more preferably 1:10.

[0074] Optionally, after step (2), a washing step is further performed to wash away any remaining mixed solution. The washing step may use a suitable washing solvent, such as but not limited to water.

[0075] Preferably, step (3) is carried out in a fixed-bed continuous flow reactor, and the acidification lasts for a third time.

[0076] The acidification temperature is not particularly limited as long as it does not affect the implementation of the present invention. For example, the acidification temperature may be the same as or different from the temperature in step (2).

[0077] In step (3), the acidic solution may be an inorganic acid solution or an organic acid solution, without particular limitation. Specifically, the acidic solution may be selected from a combination of one or more of hydrochloric acid, nitric acid, phosphoric acid, etc., with hydrochloric acid being most preferred.

[0078] Preferably, in step (3), the acid concentration of the acidic solution is 0.1 mol / L to 10 mol / L. The upper limit of the acid concentration is more preferably 5 mol / L, and still more preferably 2 mol / L. The lower limit of the acid concentration is more preferably 0.2 mol / L, and still more preferably 0.5 mol / L. The most preferably acid concentration is about 1 mol / L.

[0079] Preferably, in step (3), the third time is 1-48 hours. The upper limit of the third time is more preferably 36 hours, more preferably 24 hours, and still more preferably 18 hours. The lower limit of the third time is more preferably 2 hours, more preferably 4 hours, more preferably 6 hours, more preferably 8 hours, and still more preferably 10 hours. The third time is most preferably around 12 hours.

[0080] In step (3), the metal ions in the acidic solution containing metal ions can be any metal ions as long as they do not affect the implementation of the present invention. The metal ions can be selected from one or more combinations of metal ions such as Cu, Na, Mg, Li, K, Ga, Zn, Ti, Cd, Ca, and Al.

[0081] Preferably, in step (3), the metal ions account for 10-1000 ppm, preferably 50-500 ppm, relative to the acidic solution.

[0082] Optionally, after step (3), a post-cleaning step is further performed to clean out any remaining acidic solution. The post-cleaning step may use a suitable cleaning solvent, such as but not limited to water.

[0083] Example

[0084] The present invention is further described in detail below by way of examples. However, the following examples are merely simple illustrations of the present invention and do not represent or limit the scope of protection of the present invention.

[0085] The deactivated resin catalyst used in the embodiment is a catalyst for the hydration reaction of hydroxyaldehydes from olefins. The hydration reaction conditions are: an olefin aqueous solution with a mass concentration of 10-20% is heated at a mass space velocity of 0.5-2.0 h -1 The catalyst bed of the acidic chelating resin is continuously passed through, wherein the ratio of the catalyst bed layer to the inner diameter of the reactor is 1 to 100, and the hydration reaction is continuously carried out under the conditions of 0.1 to 0.5 MPa and 20 to 60° C. to generate hydroxy aldehyde.

[0086] A fixed-bed continuous flow reactor (CFFR) is a chemical reaction device used to process chemical reactions involving gases and liquids. It consists of a fixed catalyst bed. Pipes and a flow control system within the bed introduce the reactants into the reactor in a continuous flow. The reaction products are then collected and separated in the fixed bed.

[0087] Inactivation means that an aqueous solution of 10-20% alkenal is heated at a mass space velocity of 0.5-2.0 h -1 The catalyst bed of the acidic chelating resin is continuously passed through to continuously perform hydration reaction to generate hydroxy aldehyde, with ACR conversion rate less than 40%, HPA selectivity less than 80%, and catalyst acid content less than 2 mmol / g.

[0088] After regeneration, the mass concentration of 10-20% of the aldehyde aqueous solution is 0.5-2.0h -1 The catalyst bed of the acidic chelating resin is continuously passed through to continuously perform hydration reaction to generate hydroxy aldehyde, with ACR conversion rate greater than 40%, HPA selectivity greater than 80%, and catalyst acid content greater than 5 mmol / g.

[0089] The resin catalyst used in the examples is a chelating resin with polystyrene as a carrier and aminocarboxylic acid / aminophosphoric acid as a functional group.

[0090] Amine content test: The catalyst N element was tested using a Thermo Fisher Flashsmart analyzer, and the amine content of the catalyst was calculated based on the N element content.

[0091] Acrolein source: Shandong Xinglu Biotechnology Co., Ltd. (99.8%)

[0092] Example 1

[0093] Place 100g of deactivated hydrated resin catalyst A in a fixed bed continuous flow reactor, and pass 1000g of deionized water from top to bottom through the resin catalyst layer to remove mechanical impurities adsorbed on the resin surface. Pass 1000g of dichloromethane from top to bottom through the resin catalyst layer at 20°C. After circulating for 12 hours, remove the organic polymer adsorbed on the resin surface. Then pass 1000g of deionized water from top to bottom through the resin catalyst layer to replace the dichloromethane solvent. Dissolve 100g of chloroacetic acid and 100g of sodium carbonate in 200g of water, pass the mixed solution from top to bottom through the resin catalyst layer at 80°C, and after circulating for 12 hours, wash the resin from top to bottom through the resin catalyst layer until it is nearly neutral, and finally wash it with 500ppm of Na +A 1 mol / L HCl solution was passed from top to bottom through the resin catalyst layer. After circulating for 12 hours, the acidic solution passed through the deactivated catalyst at a rate of 3 BV / h, acidifying the resin to acidity and replenishing the lost active groups in the resin. Finally, 1000 g of deionized water was passed from top to bottom through the resin catalyst layer to replace the unreacted acidic solution.

[0094] The acid content of the resin before catalyst regeneration is 1.5 mmol.g -1 The acid content of the resin after catalyst regeneration is 5.8 mmol.g -1 .

[0095] Equal masses of the resin catalyst before and after regeneration were weighed and subjected to acrolein hydration catalytic reaction at 60°C. Before the reaction, the acrolein conversion was 33%, the selectivity was 71%, and the fresh catalyst life was 100-50 hours. After regeneration, the acrolein conversion was 56%, the selectivity was 91%, and the regenerated catalyst life was 100-10 hours.

[0096] Examples 2-5

[0097] Examples 2-5 vary the type of acidic functional groups and their reactive content based on Example 1, while other conditions remain unchanged. The experimental results are shown in Table 1.

[0098] Table 1

[0099]

[0100] Examples 6-8

[0101] Examples 6-8 vary the type of alkaline catalyst and its reaction content based on Example 1, while other conditions remain unchanged. The experimental results are shown in Table 2.

[0102] Table 2

[0103]

[0104] Examples 9-11

[0105] Examples 9-11 vary the type of metal ions and their reaction contents based on Example 1, while other conditions remain unchanged. The experimental results are shown in Table 3.

[0106] Table 3

[0107]

[0108] Examples 12-14

[0109] Examples 12-14 omitted certain steps from Example 1. In Example 12, only solvent elution was performed; neither replenishment of lost functional groups nor metal ion modification was performed. In Example 13, only solvent elution and replenishment of lost functional groups were performed; no metal ion modification was performed. In Example 14, only solvent elution and metal ion modification were performed; no replenishment of lost functional groups was performed. All other conditions remained unchanged. The experimental results are shown in Table 4.

[0110] Table 4

[0111]

[0112] This shows that the three-step catalyst regeneration operation steps of solvent elution, replenishment of lost functional groups, and metal ion modification all play a key role in the recovery of catalyst activity.

[0113] While the present invention is described through the above-described embodiments to illustrate the detailed structural features of the present invention, the present invention is not limited to these detailed structural features, nor does it necessarily rely on these detailed structural features for implementation. Those skilled in the art should understand that any improvements to the present invention, equivalent replacements for selected components, additions of auxiliary components, and selection of specific embodiments, etc., fall within the scope of protection and disclosure of the present invention.

Claims

1. A method for regenerating a resin catalyst, wherein the resin catalyst is a resin catalyst for preparing hydroxy aldehydes by hydrating alkenal, characterized in that: The method comprises the following steps: (1) eluting a deactivated resin catalyst with a first solvent at a first temperature, wherein the deactivated resin catalyst is an aminocarboxylic acid or aminophosphoric acid chelate resin catalyst having an amino group on its surface; (2) contacting a mixed solution of a substance containing an acidic functional group and a basic catalyst with a resin catalyst at a second temperature, wherein the substance containing an acidic functional group is selected from a combination of one or more of chloroacetic acid, chloropropionic acid, methyl chloroacetate, methyl chloropropionate, and chloromethylphosphonic acid, and the basic catalyst is selected from a combination of one or more of sodium carbonate, sodium hydroxide, potassium carbonate, potassium hydroxide, triethylamine, sodium methoxide, potassium ethoxide, potassium tert-butoxide, and ethylenediamine; (3) Acidifying the resin catalyst with an acidic solution containing metal ions, wherein the metal ions in the acidic solution containing metal ions are selected from a combination of one or more of Cu, Na, Mg, Li, K, Ga, Zn, Ti, Cd, Ca, and Al, and the acidic solution is an acidic solution of an inorganic acid.

2. The method according to claim 1, which satisfies any one of the following conditions: Step (1) is carried out in a fixed bed continuous flow reactor, wherein the first solvent is pumped into the catalyst bed and circulated for a first time; or Step (2) is carried out in a fixed-bed continuous flow reactor, wherein the mixed solution passes through the resin catalyst layer in the fixed-bed continuous flow reactor from top to bottom and circulates for a second time; or Step (3) is carried out in a fixed bed continuous flow reactor, and the acidification lasts for a third time; It further satisfies any of the following: In step (1), the first temperature is 10-200°C; In step (1), the first time is 1-72 hours; In step (1), the mass ratio of the resin catalyst to the first solvent is 1:2-1:100; In step (2), the second temperature is 10-200°C; In step (2), the second time is 1-48 hours; In step (2), the molar ratio of the amine-containing group to the acidic functional group-containing substance in the resin treated in step (1) is 1:1-1:10; In step (2), the molar ratio of the amine-containing groups in the resin treated in step (1) to the alkaline catalyst is 1:1-1:20; In step (2), the molar ratio of the substance containing an acidic functional group to the solvent is 1:1-1:100; In step (3), the acid concentration of the acidic solution is 0.1 mol / L-10 mol / L; In step (3), the third time is 1-48 hours; In step (3), the acidic solution passes through the deactivated catalyst at a rate of 1-5 BV / h; In step (3), the metal ions account for 10-1000 ppm relative to the acidic solution.

3. The method according to claim 1, wherein The amine content of the deactivated resin catalyst accounts for 2-8%.

4. The method according to claim 1, wherein In step (3), the metal ions in the acidic solution containing metal ions are selected from one or more combinations of Na, Zn, Ti, and Ca.

5. The method according to claim 1, wherein In step (1), the first solvent is selected from one or more combinations of dichloromethane, dichloroethane, methanol, ethanol, acetonitrile, toluene, benzene, ethylbenzene, PEG-200, cyclohexane, cyclohexanol, N,N-dimethylformamide or dimethyl sulfoxide.

6. The method of claim 1, wherein: In step (1), the mass ratio of the resin catalyst to the first solvent is 1:2-1:

100.

7. The method according to claim 1, which satisfies any one of the following conditions: In step (2), the substance containing an acidic functional group is selected from one or more combinations of chloroacetic acid, chloropropionic acid, methyl chloroacetate, and chloromethylphosphonic acid; or In step (2), the alkaline catalyst is selected from a combination of one or more of sodium carbonate, potassium carbonate, triethylamine, and potassium hydroxide; In step (3), the acidic solution is selected from a combination of one or more of hydrochloric acid, nitric acid, and phosphoric acid.

8. A resin catalyst obtained by regenerating by the method according to any one of claims 1 to 7.

9. A method for preparing hydroxy aldehydes by catalyzing the hydration of olefinic aldehydes using a resin catalyst, wherein: The catalyst is regenerated in situ by the method according to any one of claims 1 to 7.

10. A method for preparing hydroxy aldehydes by hydrating alkenal, characterized in that: The method comprises the following steps: (1) Preparation of hydroxy aldehydes using resin catalysts; (2) Determine whether the resin catalyst is deactivated; (3) In situ regeneration of the resin catalyst by the method according to any one of claims 1 to 7.

Images