Preparation method of ether

Abstract

The invention discloses an ether preparation method which comprises the following steps: carrying out contact reaction on ethylene glycol and a catalyst to obtain diethylene glycol; the catalyst is modified cation exchange resin. The catalyst provided by the invention is applied to a reaction for preparing diethylene glycol through ethylene glycol dehydration reaction, so that the conversion rate of ethylene glycol and the selectivity of the generated diethylene glycol are improved.

Description

Technical Field

[0001] The present application relates to a method for preparing ether, belonging to the field of chemical industry. Background Art

[0002] As the reserves of oil resources are getting smaller and smaller, the prices of petrochemical products are rising. In view of my country's relatively coal-rich energy structure, using coal as raw material to replace oil production has become a development trend in China in recent years. With the continuous advancement of coal-to-ethylene glycol technology, the continuous optimization and improvement of large-scale coal-to-ethylene glycol technology, the route of synthetic gas to ethylene glycol has gradually achieved industrialization. In the near future, the output of ethylene glycol will increase, and the price of ethylene glycol products will continue to decline. Developing downstream products of ethylene glycol and improving the economic benefits of products will be the current research hotspot.

[0003] Due to the rapid development of industrialization, the global industrial pollution problem has received more and more attention, and people's environmental awareness has become stronger and stronger. It is well known that the protonic acid mainly used in traditional industry has disadvantages such as corrosiveness and toxicity. Its application in the dehydration reaction of ethylene glycol not only causes great corrosion to the equipment, but also has serious side reactions. At the same time, the large amount of waste acid and wastewater generated by this method is difficult to handle, which not only increases industrial costs but also causes some waste of resources. Therefore, the development of a catalyst with high activity, good stability, low cost and environmental protection has good industrial application prospects.

[0004] Solid acid catalysts have become the focus of researchers due to their many advantages such as high activity, high selectivity and easy separation. There are still few solid acid catalysts reported in the literature for catalyzing the dehydration reaction of ethylene glycol. With the advancement of science and technology and the improvement of people's environmental awareness, in chemical production, a solid acid catalyst with advantages such as recyclability and reuse is gradually replacing traditional proton acid catalysts. Summary of the invention

[0005] The present invention is of great significance to apply the modified cation exchange resin catalyst in the preparation process of diethylene glycol. The catalyst has good activity, high ethylene glycol conversion rate and diethylene glycol selectivity, and good stability.

[0006] According to one aspect of the present application, a method for preparing diethylene glycol is provided, the method comprising: contacting ethylene glycol with a modified cation exchange resin, reacting to obtain diethylene glycol;

[0007] The modified cation exchange resin is obtained by modifying the cation exchange resin with a modifying substance;

[0008] The modified substance is selected from at least one of an inorganic acid, an ammonium salt, and a metal salt;

[0009] The mass of the modified substance is 1 to 10 wt % of the mass of the modified cation exchange resin.

[0010] Optionally, the cation exchange resin is selected from at least one of Amberlyst 15, Amberlyst 16, Amberlyst 21, Amberlyst 35, Amberlyst 36, and Amberlyst 45.

[0011] Optionally, the modified cation exchange resin catalyst is obtained by modifying a modified material cation exchange resin.

[0012] Optionally, the modifying substance is selected from at least one of an inorganic acid, an ammonium salt, and a metal salt.

[0013] Optionally, the ammonium salt is selected from at least one of diammonium hydrogen phosphate and ammonium fluoride.

[0014] Optionally, the metal salt is selected from at least one of zinc nitrate, lanthanum nitrate, magnesium nitrate and potassium nitrate.

[0015] Optionally, the mass of the modified substance (metal salt is calculated as oxide mass) is 1 to 10 wt % of the mass of the modified cation exchange resin catalyst.

[0016] Optionally, the mass of the modified substance (metal salt is measured as oxide mass) is any value of 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt% of the mass of the modified cation exchange resin catalyst, or a range between any two of the above.

[0017] Optionally, the reaction temperature is 80-200°C.

[0018] Optionally, in the reaction, the N2 flow rate is 0-30 ml / min.

[0019] Optionally, the mass space velocity of the reaction is 0.2 to 2 h -1 .

[0020] Optionally, the reaction temperature is selected from any value of 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C or a range between any two of the above.

[0021] Optionally, in the reaction, the N2 flow rate is selected from any value of 0 ml / min, 5 ml / min, 10 ml / min, 15 ml / min, 20 ml / min, 25 ml / min, 30 ml / min or a range between any two of the above.

[0022] Optionally, the mass space velocity of the reaction is 0.2h -1 、0.4h -1 、0.6h -1 , 0.8h -1 , 1.0h -1 , 1.2h -1 , 1.4h -1 , 1.6h -1 , 1.8h -1 , 2.0h -1 Any value in or a range between any two of the above.

[0023] Optionally, the preparation method of the modified cation exchange resin comprises: immersing an equal volume of the cation exchange resin in a modifying substance, stirring, immersing, and drying to obtain the modified cation exchange resin.

[0024] Optionally, the stirring time is 5 to 20 minutes.

[0025] Optionally, the immersion time is 4 to 10 hours.

[0026] Optionally, the drying temperature is 80 to 130° C., and the drying time is 6 to 24 hours;

[0027] Optionally, the stirring time is selected from any value of 5 minutes, 10 minutes, 15 minutes, 20 minutes, or a range between any two of the above.

[0028] Optionally, the immersion time is selected from any value of 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, or a range between any two of the above.

[0029] Optionally, the drying temperature is selected from any value of 80°C, 90°C, 100°C, 110°C, 120°C, 130°C or a range between any two of the above values.

[0030] Optionally, the drying time is selected from any value among 6 hours, 8 hours, 10 hours, 12 hours, 14 hours, 16 hours, 18 hours, 20 hours, or a range between any two of the above.

[0031] The beneficial effects of this application include:

[0032] 1) The catalyst provided in the present application can be applied to the dehydration reaction of ethylene glycol to prepare diethylene glycol, and improve the conversion rate of ethylene glycol and the selectivity of the generated diethylene glycol.

[0033] 2) The preparation method of the catalyst provided in this application is stable, controllable and has good reproducibility.

[0034] 3) The method for preparing diethylene glycol by dehydration of ethylene glycol provided in the present application uses the catalyst provided in the present application, has a fast reaction speed and a high yield, and can be applied to large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Catalyst 5 for this application # Reaction results 9 # Gas chromatography-mass spectrometry diagram. DETAILED DESCRIPTION

[0036] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0037] Unless otherwise specified, the raw materials and catalysts in the examples of this application were purchased through commercial channels.

[0038] The gas chromatograph is a 7890B gas chromatograph from Agilent.

[0039] In the examples of this application, the conversion rate and selectivity are calculated as follows:

[0040] The conversion rate and selectivity calculation formula in the examples of the present application are as follows (with ethylene glycol conversion rate as the evaluation index):

[0041] Ethylene glycol conversion rate = (initial carbon number of ethylene glycol - carbon number of ethylene glycol in the product) * 100 / initial mole number of ethylene glycol

[0042] Diethylene glycol selectivity = carbon number of diethylene glycol*100 / ∑(carbon number of diethylene glycol+carbon number of other products).

[0043] Example 1

[0044] A 5% phosphoric acid solution was prepared, 10 g of the solution was weighed, 20 g of Amberlyst 15 cationic resin was transferred to the solution, stirred for 10 minutes, immersed for 6 hours, and dried in an oven at 110° C. for 10 hours to obtain a modified cationic exchange resin, which was recorded as catalyst 1. # .

[0045] Example 2

[0046] Prepare a 6% boric acid solution, weigh 10 g of the solution, transfer 20 g of Amberlyst 45 cationic resin into the solution, stir for 5 minutes, soak for 8 hours, and dry in an oven at 100° C. for 14 hours to obtain a modified cationic exchange resin, which is recorded as catalyst 2. # .

[0047] Example 3

[0048] Prepare a 10% by mass diammonium hydrogen phosphate solution, weigh 10 g of the solution, transfer 20 g of Amberlyst 21 cationic resin into the solution, stir for 15 minutes, soak for 7 hours, and dry in an oven at 120° C. for 16 hours to obtain a modified cationic exchange resin, which is recorded as catalyst 3. # .

[0049] Example 4

[0050] Prepare an 8% ammonium fluoride solution, weigh 10 g of the solution, transfer 20 g of Amberlyst 35 cationic resin into the solution, stir for 20 minutes, soak for 10 hours, and dry in an oven at 90° C. for 8 hours to obtain a modified cationic exchange resin, which is recorded as catalyst 4. # .

[0051] Example 5

[0052] Weigh zinc nitrate with a zinc oxide mass percentage of 10%, dissolve it in 10g of deionized water, transfer 20g of Amberlyst 36 cationic resin to the solution, stir for 10 minutes, soak for 9 hours, and dry in an oven at 130°C for 6 hours to obtain a modified cationic exchange resin, which is recorded as catalyst 5. # .

[0053] Example 6

[0054] Weigh 8% lanthanum nitrate containing lanthanum oxide by mass, dissolve it in 10 g of deionized water, transfer 20 g of Amberlyst 16 cationic resin to the solution, stir for 5 minutes, soak for 4 hours, and dry in an oven at 80° C. for 12 hours to obtain a modified cationic exchange resin, which is recorded as catalyst 6. # .

[0055] Example 7

[0056] Magnesium nitrate with a magnesium oxide mass percentage of 7% was weighed and dissolved in 10 g of deionized water. 20 g of Amberlyst 15 cationic resin was transferred to the solution. After stirring for 15 minutes, it was immersed for 5 hours and dried in an oven at 100° C. for 20 hours to obtain a modified cationic exchange resin, which was recorded as catalyst 7. # .

[0057] Example 8

[0058] Weigh potassium nitrate with a potassium oxide mass percentage of 6%, dissolve it in 10g of deionized water, transfer 20g of Amberlyst45 cationic resin to the solution, stir for 20 minutes, soak for 8 hours, and dry in an oven at 110°C for 14 hours to obtain a modified cationic exchange resin, which is recorded as catalyst 8. # .

[0059] Example 9

[0060] Catalyst 1 prepared in Examples 1 to 8 was used # ~Catalyst 8 # The reaction of preparing diethylene glycol by dehydration of ethylene glycol was carried out, and the reaction parameters were changed. After the reaction was stable (reaction for 6 hours), the reaction raw materials and products were analyzed by gas chromatography online. The composition of the ethylene glycol dehydration reaction product was analyzed using Agilent 7890B gas chromatograph (FID detector, FFAP capillary column). The reaction results are shown in Table 1.

[0061] Table 1

[0062]

[0063]

[0064] Figure 1 Catalyst 5 for this application # Reaction results 9 # GC-MS graph, from Figure 1 It can be seen that the main product diethylene glycol has a high selectivity and the by-products are all known substances.

[0065] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for preparing ether, characterized in that: The preparation method comprises: contacting ethylene glycol with a modified cation exchange resin to react and obtain diethylene glycol; The modified cation exchange resin is obtained by modifying the cation exchange resin with a modifying substance; The modified substance is selected from at least one of an inorganic acid, an ammonium salt, and a metal salt; The mass of the modified substance is 1 to 10 wt % of the mass of the modified cation exchange resin; The ether is diethylene glycol.

2. The preparation method according to claim 1, characterized in that: The cation exchange resin is selected from at least one of Amberlyst 15, Amberlyst 16, Amberlyst 21, Amberlyst 35, Amberlyst 36, and Amberlyst 45.

3. The preparation method according to claim 1, characterized in that: The inorganic acid is selected from phosphoric acid and / or boric acid.

4. The preparation method according to claim 1, characterized in that: The ammonium salt is selected from diammonium hydrogen phosphate and / or ammonium fluoride.

5. The preparation method according to claim 1, characterized in that: The metal salt is selected from at least one of zinc nitrate, lanthanum nitrate, magnesium nitrate and potassium nitrate.

6. The preparation method according to claim 1, characterized in that: The reaction temperature is 80-200°C; In the reaction, the N2 flow rate is 0-30 ml / min; The mass space velocity of the reaction is 0.2 to 2 h -1 .

7. The preparation method according to claim 1, characterized in that: The preparation method of the modified cation exchange resin comprises: An equal volume of the cation exchange resin is impregnated in the modified substance, stirred, impregnated, and dried to obtain the modified cation exchange resin.

8. The preparation method according to claim 7, characterized in that: The stirring time is 5 to 20 minutes.

9. The preparation method according to claim 7, characterized in that: The immersion time is 4 to 10 hours.

10. The preparation method according to claim 7, characterized in that: The drying temperature is 80 to 130° C., and the drying time is 6 to 24 hours.

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