A pressure swing adsorption hydrogen purification adsorbent for synthesizing morpholine and its preparation method

Abstract

The present invention relates to the technical field of adsorbents, and specifically discloses a pressure swing adsorption hydrogen purification adsorbent for synthesizing morpholine and a preparation method thereof. The specific preparation method comprises the following steps: Step a: grinding the binder into powder for standby; Step b: mixing 13X molecular sieve, binder, structure stabilizer and calcium compound in a certain proportion, and forming a spherical compound A after mixing; Step c: pre-drying the spherical compound A, followed by roasting, washing, drying and activation to obtain the adsorbent. The pressure swing adsorption hydrogen purification adsorbent for synthesizing morpholine provided by the present invention has good adsorption effect, can tolerate high concentration of CO2, and a structure stabilizer is added to the adsorbent, so that the prepared adsorbent has a stable structure and can tolerate the influence of gas flow scouring, particle and bed vibration on the adsorbent. Finally, the preparation method of the adsorbent of the present invention is simple and easy for industrial production.

Description

[0001] The present invention relates to the technical field of pressure swing adsorption, and particularly to a pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine and a preparation method thereof. Background Art

[0002] The basic principle of pressure swing adsorption (PSA) is a separation process designed based on the principle that different adsorbates in a mixture have different adsorption amounts on an adsorbent, and the adsorption amount of the same adsorbate on the adsorbent changes with the partial pressure of the adsorbate. The adsorption amount of the adsorbate on the adsorbent changes with the partial pressure of the adsorbate at a certain temperature, and this change relationship is described by an adsorption isotherm.

[0003] The adsorption amount of the adsorbate on the adsorbent changes with the partial pressure of the adsorbate at a certain temperature, and this change relationship can be described by an adsorption isotherm. As Figure 1 shown in the figure, A and B are the adsorption isotherms of two different adsorbates at the same temperature. It can be seen from the figure that at the same adsorption temperature, A is more easily adsorbed than B, and A is a strong adsorption component relative to B. When a mixture of A and B is adsorbed under high pressure (assuming the partial pressures of A and B are PA2 and PB2 respectively), and desorbed and regenerated under low pressure (assuming the partial pressures of A and B are both PA1 and PB1). When the adsorption proceeds to a certain stage, the two reach adsorption equilibrium, and the adsorption amounts are q A2 and q B2 , q A2 >q B2 , so the content of A in the effluent gas stream of the adsorption bed is less than that of B during the adsorption stage, and it is a B-rich gas stream. When the adsorption reaches a certain degree, the adsorption bed starts to depressurize and desorb, and the adsorption amounts of A and B are q A1 and q B1 . During this process, the adsorption capacities of the adsorption bed for A and B are Δq A =q A2 -q A1 and Δq B =q B2 -q B1 , the former is greater than the latter, so in the desorbed effluent gas of the adsorption bed, the content of component A is greater than that of B. The adsorption bed realizes the separation of components A and B through this process of high-pressure adsorption and low-pressure desorption.

[0004] In the process of synthesizing morpholine, the function of the pressure swing adsorption hydrogen extraction process is to separate H 2 from components such as CO, N 2 , CH 4 to obtain a high-purity H 2 product gas. The pressure swing adsorption hydrogen extraction process adopts a six-column three-stage equal pressure process. CO, N 2 , CH 4 in the raw material gas are adsorbed by the adsorbent, and H 2As the adsorbed tail gas flows out of the adsorption tower and is sent to the subsequent process, the adsorbed CO and N 2 , CH 4 are desorbed by the methods of co-current pressure release, counter-current pressure release and flushing, and at the same time the adsorbent is regenerated. Therefore, developing and preparing an adsorbent that meets the production requirements of morpholine is an important key point in the pressure swing adsorption hydrogen production process.

[0005] In the PSA-H 2 section for synthesizing morpholine, generally CO, N 2 and CH 4 are used as target adsorbates. When the adsorbent is not fast enough to adsorb these substances, these substances will penetrate through the adsorption tower bed and appear in the H 2 product gas, affecting the purity of the H 2 product gas. Often, the process gas contains not only the above three gases, but also other impurities, such as CO 2 , but currently the adsorbent used in the H 2 section has poor tolerance to CO 2 gas and is prone to adsorbent poisoning, thus reducing the separation efficiency. When the impurity components of the raw material gas change, especially when the CO 2 content in the raw material gas changes greatly, it may be necessary to adjust the device, and even stop the gas intake when necessary, seriously affecting the production efficiency of the PSA-H 2 section.

[0006] The adsorbent filled in the adsorption tower usually includes activated carbon, molecular sieve, and silica gel / activated alumina. The main function of silica gel / activated alumina is to separate components with relatively high boiling points and relatively easy to adsorb, such as water vapor, light hydrocarbons, and methanol. Activated carbon and molecular sieve are generally used in combination, and their main function is to separate components with relatively low boiling points and relatively difficult to adsorb, such as CO 2 , CH 4 , N 2 , etc. Among them, 5A molecular sieve is commonly used for molecular sieve. At present, the performance indicators of the activated carbon and molecular sieve filled in the adsorption tower of the pressure swing adsorption hydrogen production process have a significant impact on the hydrogen production effect. In the PSA-H 2 section of the morpholine synthesis process, the automatic valves at the inlet and outlet of the adsorption tower have relatively frequent actions, and it is necessary to accurately control the opening and closing and opening degree of the valves according to the time sequence. Due to the requirements of gas flow erosion, particles and bed vibration, as well as the pollution of activated carbon dust to the subsequent process or the cleaning of the filter, a molecular sieve adsorbent with relatively high stability is required. Summary of the Invention

[0007] The purpose of the present invention is to provide a pressure swing adsorption hydrogen production adsorbent for synthesizing morpholine with good tolerance to CO 2 and high adsorbent stability, as well as a preparation method of the adsorbent, aiming at the disadvantages of the currently used adsorbents on the market.

[0008] A preparation method of a pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine, characterized by comprising the following steps:

[0009] Step a: Grind the binder into powder for later use;

[0010] Step b: Mix 13X molecular sieve, binder, structure stabilizer and calcium compound in a certain proportion, and make a spherical compound A after mixing;

[0011] Step c: Pre-dry the spherical compound A, and then carry out roasting, water washing, drying and activation to obtain the adsorbent.

[0012] Further, in the step a, the binder is kaolin.

[0013] Further, in the step b, the calcium compound is selected from at least one of calcium oxide, calcium chloride and calcium hydroxide.

[0014] Further, in the step b, the calcium compound is calcium oxide and calcium chloride.

[0015] Further, in the step b, the structure stabilizer is MgO or Fe 2 O 3 .

[0016] Further, in the step b, the content ratio of the calcium compound to the 13X molecular sieve is 20-50 mmol Ca + : 100 g of 13X molecular sieve, and the content ratio of the kaolin, structure stabilizer to the 13X molecular sieve is 0.15∶0.05∶5. Calculated by the dry weight of the adsorbent, the content of the 13X molecular sieve in the adsorbent is above 90% by weight.

[0017] Further, in the step b, the spherical compound A is prepared in a ball mill after adding water to 13X molecular sieve, kaolin, structure stabilizer and calcium compound.

[0018] Further, in the step b, the pre-drying temperature is 65-85 °C, and the drying time is 3-4 hours; the roasting temperature is 600-700 °C, and the time is 3-5 hours; the water washing temperature is 85-95 °C, and the water washing time is 5 hours.

[0019] Further, in the step c, the activation is carried out in a rotary kiln. During the activation process, the atmosphere in the rotary kiln is nitrogen, and the pressure is slightly positive pressure. The activation method is the programmed heating method. The temperature in the first stage rises from 300 °C to 450 °C, and the heating time is 2-4 hours, and then the temperature is maintained at 450 °C for 1 hour.

[0020] The present invention also provides an adsorbent prepared by any of the above methods. The adsorbent is applied to the pressure swing adsorption hydrogen extraction process for synthesizing morpholine. The adsorbent is filled in an adsorption tower, and the adsorption tower is provided with an adsorbent packing area. At the lower end of the adsorbent packing area, there is an adsorbent packing support, and a vibration motor is provided on the adsorbent packing support. The vibration arm of the vibration motor extends upward into the adsorbent packing area;

[0021] Preferably, the adsorbent packing support is densely distributed with micropores. The micropores on the adsorbent packing support are composed of two circular holes with different apertures that are connected up and down, and the aperture of the circular hole on the side close to the adsorbent packing area is smaller than the aperture of the circular hole on the side far from the adsorbent packing area.

[0022] The beneficial effects of the present invention are as follows:

[0023] 1. For the pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine provided by the present invention, during the synthesis of morpholine, due to the use of 13X molecular sieve material in the preparation process of the adsorbent and the addition of calcium compounds, the dual action enhances the tolerance of the adsorbent to CO in the process gas, and the adsorption effect is better. 2 And the adsorption effect is better.

[0024] 2. A structure stabilizer is added to the adsorbent of the present invention, so that the prepared adsorbent has a stable structure and can withstand the influence of gas flow scouring, particles and bed vibration on the adsorbent.

[0025] 3. The preparation method of the pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine provided by the present invention is divided into 3 operation steps. Compared with the traditional impregnation method, it does not require an impregnation step. The preparation method is simple, saves costs and energy, and the raw materials have a wide source and are easy to use industrially. Description of the Drawings

[0026] Figure 1 Is the adsorption isotherm of Adsorbents A and B;

[0027] Figure 2 Is the flow chart of the pressure swing adsorption hydrogen extraction adsorption equipment;

[0028] Figure 3 Is the comparison result of the adsorption stability of the adsorbents prepared in Example 4, Comparative Example 4, Comparative Example 5 and Comparative Example 6;

[0029] Figure 4 Is the schematic structural diagram of the adsorption tower in Example 12 of the present invention;

[0030] Figure 5 Is the schematic cross-sectional structure diagram of the adsorbent packing support of the adsorption tower in Example 12 of the present invention. Detailed Embodiments

[0031] Example 1

[0032] Preparation of Adsorbent

[0033] Step a: Grind the massive kaolin into powder for later use;

[0034] Step b: Weigh 90 g of 13X molecular sieve, 2.7 g of kaolin, 0.9 g of MgO and 18 mmol of calcium chloride, mix them, and add water in a ball mill to make a spherical compound A;

[0035] Step c: The spherical compound A is pre-dried in a dryer at 65 °C for 4 hours to reduce the moisture content of the spherical compound A. The pre-dried spherical compound A enters a rotary kiln and is calcined at 600 °C for 5 hours to remove the structural water and the wet water in the formed shape, achieving solid-state ion exchange. Then it is soaked in constant-temperature hot water at 90 °C for 5 hours, and finally enters the rotary kiln for activation. Under a nitrogen atmosphere and slightly positive pressure, the temperature is programmed from 300 °C to 450 °C for 4 hours, and then the temperature is maintained at 450 °C for 1 hour to increase the thermal stability after artificial treatment, and the preparation of the adsorbent is completed.

[0036] Detection of Adsorbent Effect

[0037] Measured by the gravimetric method: The adsorbent prepared above has an adsorption capacity of 81 ml / g for carbon dioxide, 76.00 ml / g for methane, and 70.06 ml / g for nitrogen at 1 standard atmosphere and 25 °C.

[0038] Example 2

[0039] Preparation of Adsorbent

[0040] Step a: Grind the massive kaolin into powder for later use;

[0041] Step b: Weigh 95 g of 13X molecular sieve, 2.85 g of kaolin, 0.95 g of MgO, 20 mmol of calcium chloride and 12 mmol of calcium oxide, mix them, and add water in a ball mill to make a spherical compound A;

[0042] Step c: The spherical compound A is pre-dried in a dryer at 75 °C for 4 hours to reduce the moisture content of the spherical compound A. The pre-dried spherical compound A enters a rotary kiln and is calcined at 600 °C for 5 hours to remove the structural water and the wet water in the formed shape, achieving solid-state ion exchange. Then it is soaked in constant-temperature hot water at 90 °C for 5 hours, and finally enters the rotary kiln for activation. Under a nitrogen atmosphere and slightly positive pressure, the temperature is programmed from 300 °C to 450 °C for 4 hours, and then the temperature is maintained at 450 °C for 1 hour to increase the thermal stability after artificial treatment, and the preparation of the adsorbent is completed.

[0043] Detection of Adsorbent Effect

[0044] Measured by the gravimetric method: the adsorbent prepared above has an adsorption capacity of 84 ml / g for carbon dioxide, 71 ml / g for methane, and 72.5 ml / g for nitrogen at 25 °C under 1 standard atmosphere.

[0045] Example 3

[0046] Preparation of the adsorbent

[0047] Step a: Grind the massive kaolin into powder for later use;

[0048] Step b: Weigh 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of MgO and 20 mmol of calcium hydroxide, mix them, and add water in a ball mill to make a spherical compound A;

[0049] Step c: The spherical compound A is pre-dried in a dryer at 85 °C for 3 hours to reduce the moisture content of the spherical compound A. After pre-drying, the spherical compound A enters a rotary kiln and is calcined at 600 °C for 5 hours to remove the structural water and the formed wet storage water of the spherical compound A, achieving solid-state ion exchange. Then it is soaked in constant-temperature hot water at 90 °C for 5 hours, and finally enters the rotary kiln for activation. Under a nitrogen atmosphere and a slightly positive pressure, the temperature is programmed from 300 °C to 450 °C for 2 hours, and then the temperature is maintained at 450 °C for 1 hour to increase the thermal stability after artificial synthesis, and the preparation of the adsorbent is completed.

[0050] Detection of the adsorbent effect

[0051] Measured by the gravimetric method: the adsorbent prepared above has an adsorption capacity of 83 ml / g for carbon dioxide, 73.00 ml / g for methane, and 70 ml / g for nitrogen at 25 °C under 1 standard atmosphere.

[0052] Example 4

[0053] Preparation of the adsorbent

[0054] Step a: Grind the massive kaolin into powder for later use;

[0055] Step b: Weigh 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of MgO, 20 mmol of calcium chloride and 12 mmol of calcium oxide, mix them, and add water in a ball mill to make a spherical compound A;

[0056] Step c: The spherical compound A is pre-dried in a dryer at 75°C for 4 hours to reduce the moisture content of the spherical compound A. The pre-dried spherical compound A enters a rotary kiln and is calcined at 600°C for 5 hours to remove the structural water and the wet water in the formed shape of the spherical compound A, achieving solid-state ion exchange. Then, it is soaked in constant-temperature hot water at 90°C for 5 hours. Finally, it enters the rotary kiln for activation. Under a nitrogen atmosphere and slightly positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours, and then the temperature is maintained at 450°C for 1 hour to increase the thermal stability after artificial treatment, completing the preparation of the adsorbent.

[0057] Adsorbent effect detection

[0058] Measured by the gravimetric method: The adsorbent prepared above has an adsorption capacity of 88 ml / g for carbon dioxide, 76.5 ml / g for methane, and 75 ml / g for nitrogen at 25°C under 1 standard atmosphere.

[0059] Example 5

[0060] Preparation of adsorbent

[0061] Step a: Grind the massive kaolin into powder for standby;

[0062] Step b: Weigh 95 g of 13X molecular sieve, 2.85 g of kaolin, 0.95 g of Fe 2 O 3 , 20 mmol of calcium chloride and 12 mmol of calcium hydroxide, mix them and add water in a ball mill to make a spherical compound A;

[0063] Step c: The spherical compound A is pre-dried in a dryer at 75°C for 4 hours to reduce the moisture content of the spherical compound A. The pre-dried spherical compound A enters a rotary kiln and is calcined at 600°C for 5 hours to remove the structural water and the wet water in the formed shape of the spherical compound A, achieving solid-state ion exchange. Then, it is soaked in constant-temperature hot water at 90°C for 5 hours. Finally, it enters the rotary kiln for activation. Under a nitrogen atmosphere and slightly positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours, and then the temperature is maintained at 450°C for 1 hour to increase the thermal stability after artificial treatment, completing the preparation of the adsorbent.

[0064] Adsorbent effect detection

[0065] Measured by the gravimetric method: The adsorbent prepared above has an adsorption capacity of 82 ml / g for carbon dioxide, 73.5 ml / g for methane, and 70 ml / g for nitrogen at 25°C under 1 standard atmosphere.

[0066] Example 6

[0067] Preparation of adsorbent

[0068] Step a: Grind the lumpy kaolin into powder for later use;

[0069] Step b: Weigh 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of Fe 2 O 3 , 20 mmol of calcium chloride and 12 mmol of calcium oxide. After mixing, add water in a ball mill to make spherical compound A;

[0070] Step c: Spherical compound A is pre-dried at 75 °C for 4 hours in a dryer to reduce the moisture content of spherical compound A. The pre-dried spherical compound A enters a rotary kiln and is calcined at 600 °C for 5 hours to remove the structural water and the wet water in the molding of spherical compound A, achieving solid-state ion exchange. Then it is soaked in constant-temperature hot water at 90 °C for 5 hours. Finally, it enters the rotary kiln for activation. Under a nitrogen atmosphere and a slightly positive pressure, the temperature is programmed from 300 °C to 450 °C for 3 hours, and then the temperature is maintained at 450 °C for 1 hour to increase the thermal stability after artificial synthesis, and the preparation of the adsorbent is completed.

[0071] Adsorbent effect detection

[0072] Measured by the gravimetric method: The adsorbent prepared above has an adsorption capacity of 84 ml / g for carbon dioxide, 73 ml / g for methane, and 71 ml / g for nitrogen at 1 standard atmosphere and 25 °C.

[0073] Example 7

[0074] Preparation of adsorbent

[0075] Step a: Grind the lumpy kaolin into powder for later use;

[0076] Step b: Weigh 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of MgO, 20 mmol of calcium chloride and 12 mmol of calcium hydroxide. After mixing, add water in a ball mill to make spherical compound A;

[0077] Step c: Spherical compound A is pre-dried at 75 °C for 4 hours in a dryer to reduce the moisture content of spherical compound A. The pre-dried spherical compound A enters a rotary kiln and is calcined at 600 °C for 5 hours to remove the structural water and the wet water in the molding of spherical compound A, achieving solid-state ion exchange. Then it is soaked in constant-temperature hot water at 90 °C for 5 hours. Finally, it enters the rotary kiln for activation. Under a nitrogen atmosphere and a slightly positive pressure, the temperature is programmed from 300 °C to 450 °C for 3 hours, and then the temperature is maintained at 450 °C for 1 hour to increase the thermal stability after artificial synthesis, and the preparation of the adsorbent is completed.

[0078] Adsorbent effect detection

[0079] Measured by the gravimetric method: The adsorbent prepared above has an adsorption capacity of 82 ml / g for carbon dioxide, 71.5 ml / g for methane, and 73.5 ml / g for nitrogen at 25°C under 1 standard atmosphere.

[0080] Example 8

[0081] Preparation of the adsorbent

[0082] Step a: Grind the massive kaolin into powder for standby.

[0083] Step b: Weigh 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of MgO, and 50 mmol of calcium chloride, mix them, and add water in a ball mill to form a spherical compound A.

[0084] Step c: The spherical compound A is pre-dried at 75°C for 4 hours in a dryer to reduce the moisture content of the spherical compound A. After pre-drying, the spherical compound A enters a rotary kiln and is calcined at 600°C for 5 hours to remove the structural water and the wet water of molding of the spherical compound A, achieving solid-state ion exchange. Then, it is soaked in constant-temperature hot water at 90°C for 5 hours, and finally enters the rotary kiln for activation. Under a nitrogen atmosphere and slightly positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours, and then the temperature is maintained at 450°C for 1 hour to increase the thermal stability after artificial synthesis, and the preparation of the adsorbent is completed.

[0085] Detection of the adsorbent effect

[0086] Measured by the gravimetric method: The adsorbent prepared above has an adsorption capacity of 82 ml / g for carbon dioxide, 71.5 ml / g for methane, and 73.5 ml / g for nitrogen at 25°C under 1 standard atmosphere.

[0087] Example 9

[0088] Preparation of the adsorbent

[0089] Step a: Grind the massive kaolin into powder for standby.

[0090] Step b: Weigh 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of MgO, and 50 mmol of calcium oxide, mix them, and add water in a ball mill to form a spherical compound A.

[0091] Step c: The spherical compound A is pre-dried in a dryer at 75°C for 4 hours to reduce the moisture content of the spherical compound A. After pre-drying, the spherical compound A enters a rotary kiln and is calcined at 600°C for 5 hours to remove the structural water and the wet water in the formed shape of the spherical compound A, achieving solid-state ion exchange. Then, it is soaked in constant-temperature hot water at 90°C for 5 hours. Finally, it enters the rotary kiln for activation. Under a nitrogen atmosphere and slightly positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours, and then the temperature is maintained at 450°C for 1 hour to increase the thermal stability after artificial treatment, completing the preparation of the adsorbent.

[0092] Adsorbent effect detection

[0093] Measured by the gravimetric method: For the adsorbent prepared above, at 1 standard atmosphere and 25°C, the carbon dioxide adsorption capacity is 82 ml / g, the methane adsorption capacity is 70.5 ml / g, and the nitrogen adsorption capacity is 74.5 ml / g.

[0094] Example 10

[0095] Preparation of adsorbent

[0096] Step a: Grind the massive kaolin into powder for standby;

[0097] Step b: Weigh 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of MgO, and 50 mmol of calcium hydroxide. After mixing, add water in a ball mill to make a spherical compound A;

[0098] Step c: The spherical compound A is pre-dried in a dryer at 75°C for 4 hours to reduce the moisture content of the spherical compound A. After pre-drying, the spherical compound A enters a rotary kiln and is calcined at 600°C for 5 hours to remove the structural water and the wet water in the formed shape of the spherical compound A, achieving solid-state ion exchange. Then, it is soaked in constant-temperature hot water at 90°C for 5 hours. Finally, it enters the rotary kiln for activation. Under a nitrogen atmosphere and slightly positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours, and then the temperature is maintained at 450°C for 1 hour to increase the thermal stability after artificial treatment, completing the preparation of the adsorbent.

[0099] Adsorbent effect detection

[0100] Measured by the gravimetric method: For the adsorbent prepared above, at 1 standard atmosphere and 25°C, the carbon dioxide adsorption capacity is 80 ml / g, the methane adsorption capacity is 70 ml / g, and the nitrogen adsorption capacity is 70.5 ml / g.

[0101] Example 11

[0102] Preparation of adsorbent

[0103] Step a: Grind the massive kaolin into powder for standby;

[0104] Step b: weighing 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of MgO, 20 mmol of calcium oxide and 12 mmol of calcium hydroxide, mixing them and adding water in a ball mill to prepare a spherical compound A;

[0105] Step c: The spherical compound A is pre-dried at 75°C in a dryer for 4 hours to reduce the moisture content of the spherical compound A. The pre-dried spherical compound A is calcined at 600°C in a rotary kiln for 5 hours to remove the structural water and molding wet water of the spherical compound A to achieve solid-state ion exchange. It is then soaked in constant temperature hot water at 90°C for 5 hours and finally activated in a rotary kiln. In a nitrogen atmosphere and slightly positive pressure, the temperature is programmed to rise from 300°C to 450°C for 3 hours, and then the temperature is maintained at 450°C for 1 hour to increase the thermal stability after artificialization, thereby completing the preparation of the adsorbent.

[0106] Adsorbent effect detection

[0107] It was measured by weight method that the adsorbent prepared above had an adsorption capacity of 83 ml / g for carbon dioxide, 73 ml / g for methane and 71.5 ml / g for nitrogen at 1 standard atmospheric pressure and 25°C.

[0108] Example 12

[0109] The prepared adsorbent is loaded in the adsorption tower. In the past, the adsorbent often had problems of incomplete or inaccurate loading during loading, especially for the adsorbent used in the pressure swing adsorption hydrogen extraction process. During the adsorption, pressure reduction, forward placement, reverse placement, flushing, and pressure increase process, due to the large spacing between the adsorbents, the adsorbents creep, roll, jump, collide, and even boil under the periodic flushing and oscillation of the reciprocating airflow, resulting in the adsorbents being pulverized little by little. The pulverization of the adsorbent makes the gaps in the adsorption tower larger and larger, and the increase in the gaps creates conditions for greater jumping. This vicious cycle continues, and over time, the adsorbent pulverizes over a large area, seriously affecting the adsorption efficiency of the adsorbent.

[0110] To this end, the adsorption tower for adsorbent loading in this embodiment is provided with an adsorbent filling area 1, an adsorbent filling bracket 4 is provided at the lower end of the adsorbent filling area 1, and a vibration motor 3 is provided on the adsorbent filling bracket 4. The vibration arm 2 of the vibration motor 3 extends upward to the adsorbent filling area 1. When the operator is loading the adsorbent filling, the vibration arm 2 is driven to vibrate by the vibration motor 3 during the loading process, so that the adsorbent is compacted and loaded. During the loading process, multiple vibrations are performed according to actual conditions to complete the loading of the adsorbent.

[0111] The adsorbent packing support 4 is densely distributed with micropores 5. The micropores 5 on the adsorbent packing support 4 are composed of two circular holes with different apertures that are connected up and down, and the aperture of the circular hole closer to the adsorbent side is smaller than the aperture of the circular hole farther from the adsorbent side. This structure ensures that the adsorbent does not fall from the circular holes and at the same time ensures that the process gas can quickly enter the adsorbent packing area 1. When the adsorption tower is working, the process gas enters the adsorption tower, passes through the micropores 5 of the adsorbent packing support 4 and enters the adsorbent packing area 1, thereby completing the adsorption of the gas.

[0112] It should be noted that the "upper" and "lower" position terms used in the present invention are based on the structure of the drawings.

[0113] Comparative Example 1

[0114] Preparation of adsorbent

[0115] Step a: Grind the massive kaolin into powder for standby;

[0116] Step b: Weigh 85 g of 13X molecular sieve, 2.55 g of kaolin, 0.85 g of MgO, 12 mmol of calcium oxide and 20 mmol of calcium chloride, mix them and add water in a ball mill to make a spherical compound A;

[0117] Step c: The spherical compound A is pre-dried in a dryer at 75 °C for 4 hours to reduce the moisture content of the spherical compound A. The pre-dried spherical compound A enters a rotary kiln and is calcined at 600 °C for 5 hours to remove the structural water and the wet water of forming of the spherical compound A, achieving solid-state ion exchange. Then it is soaked in constant-temperature hot water at 90 °C for 5 hours, and finally enters the rotary kiln for activation. Under a nitrogen atmosphere and slightly positive pressure, the temperature is programmed from 300 °C to 450 °C for 3 hours, and then the temperature is maintained at 450 °C for 1 hour to increase the thermal stability after artificial synthesis, and the preparation of the adsorbent is completed.

[0118] Adsorbent effect detection

[0119] Measured by the gravimetric method: The adsorbent prepared above has an adsorption capacity of 75 ml / g for carbon dioxide, 67.5 ml / g for methane, and 63 ml / g for nitrogen at 1 standard atmosphere and 25 °C.

[0120] Comparative Example 2

[0121] Preparation of adsorbent

[0122] Step a: Grind the massive kaolin into powder for standby;

[0123] Step b: Weigh 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of MgO, 60 mmol of calcium chloride, mix them and add water in a ball mill to make a spherical compound A;

[0124] Step c: The spherical compound A is pre-dried in a dryer at 75°C for 4 hours to reduce the moisture content of the spherical compound A. After pre-drying, the spherical compound A enters a rotary kiln and is calcined at 600°C for 5 hours to remove the structural water and the wet water in the formed shape of the spherical compound A, achieving solid-state ion exchange. Then, it is soaked in constant-temperature hot water at 90°C for 5 hours. Finally, it enters the rotary kiln for activation. Under a nitrogen atmosphere and a slightly positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours, and then the temperature is maintained at 450°C for 1 hour to increase the thermal stability after artificial synthesis, completing the preparation of the adsorbent.

[0125] Adsorbent effect detection

[0126] Measured by the gravimetric method: For the adsorbent prepared above, at 1 standard atmosphere and 25°C, the carbon dioxide adsorption capacity is 74 ml / g, the methane adsorption capacity is 71.5 ml / g, and the nitrogen adsorption capacity is 72 ml / g.

[0127] Comparative Example 3

[0128] Preparation of adsorbent

[0129] Step a: Grind the massive kaolin into powder for standby;

[0130] Step b: Weigh 100 g of 13X molecular sieve, 3 g of kaolin, 1 g of MgO, and 15 mmol of calcium chloride. After mixing, add water in a ball mill to make a spherical compound A;

[0131] Step c: The spherical compound A is pre-dried in a dryer at 75°C for 4 hours to reduce the moisture content of the spherical compound A. After pre-drying, the spherical compound A enters a rotary kiln and is calcined at 600°C for 5 hours to remove the structural water and the wet water in the formed shape of the spherical compound A, achieving solid-state ion exchange. Then, it is soaked in constant-temperature hot water at 90°C for 5 hours. Finally, it enters the rotary kiln for activation. Under a nitrogen atmosphere and a slightly positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours, and then the temperature is maintained at 450°C for 1 hour to increase the thermal stability after artificial synthesis, completing the preparation of the adsorbent.

[0132] Adsorbent effect detection

[0133] Measured by the gravimetric method: For the adsorbent prepared above, at 1 standard atmosphere and 25°C, the carbon dioxide adsorption capacity is 71 ml / g, the methane adsorption capacity is 70.5 ml / g, and the nitrogen adsorption capacity is 69 ml / g.

[0134] Comparative Example 4

[0135] Compared with Example 4 in the preparation of the adsorbent, only the structural stabilizer is not added, and other preparation steps remain unchanged to prepare the adsorbent.

[0136] Adsorbent Effect Detection

[0137] Measured by the gravimetric method: The adsorbent prepared above has an adsorption capacity of 70 ml / g for carbon dioxide, 66.5 ml / g for methane, and 68 ml / g for nitrogen at 25 °C under 1 standard atmosphere.

[0138] Comparative Example 5

[0139] The preparation of the adsorbent is the same as that of Example 4, except that the structural stabilizer is not added, and the other preparation steps remain unchanged, and the adsorbent is prepared.

[0140] Adsorbent Effect Detection

[0141] The adsorbent obtained by repeating the preparation method 40 times was measured by the gravimetric method: The adsorption capacity of the 40th adsorbent for carbon dioxide was 50 ml / g, for methane was 52.5 ml / g, and for nitrogen was 50 ml / g at 25 °C under 1 standard atmosphere.

[0142] Comparative Example 6

[0143] Preparation of Adsorbent

[0144] Compared with Example 4, the preparation steps remain unchanged, and the adsorbent is prepared.

[0145] Adsorbent Effect Detection

[0146] The adsorbent obtained by repeating the preparation method 40 times was measured by the gravimetric method: The adsorption capacity of the 40th adsorbent for carbon dioxide was 71 ml / g, for methane was 65.5 ml / g, and for nitrogen was 65 ml / g at 25 °C under 1 standard atmosphere.

[0147] The adsorption stability of the adsorbents in Comparative Example 5 and Comparative Example 6 was tested on a NETZSCH thermogravimetric analyzer of Netzsch Company, and the results are as Figure 3 shown.

[0148] Commercial Example

[0149] A molecular sieve adsorbent sold on the market was purchased, an adsorbent sold by a manufacturer in Beijing, and this adsorbent is a 5A molecular sieve adsorbent.

[0150] Adsorbent Effect Detection

[0151] Measured by the gravimetric method: The adsorption capacity of the adsorbent prepared above for carbon dioxide was 65 ml / g, for methane was 72.5 ml / g, and for nitrogen was 71 ml / g at 25 °C under 1 standard atmosphere.

[0152] The adsorption effects of the pressure swing adsorption hydrogen extraction adsorbents for synthesizing morpholine prepared in the above embodiments and comparative examples are summarized in Tables 1 and 2 below.

[0153] Table 1 Preparation parameters of the adsorbents in each embodiment and comparative example

[0154]

[0155] Table 2 Adsorption effects of the adsorbents in each embodiment and comparative example

[0156]

[0157] In order to compare and determine the ratio of calcium compounds in the adsorbent, the experiment in Table 3 below was designed.

[0158] Table 3 Exploration experiment of calcium compounds in the adsorbent

[0159]

[0160] Through the experimental design in Table 3 above and combined with the corresponding adsorption effects of the adsorbents in Table 2, it is not difficult to conclude by comparison that when the calcium compound is a combination of calcium chloride and calcium oxide, the adsorption effect of the prepared adsorbent is the best. Particularly obvious is the adsorption effect of this adsorbent on carbon dioxide. Therefore, the adsorbent prepared with calcium chloride and calcium oxide as calcium compounds can better tolerate carbon dioxide in the process gas. When using a single calcium compound or other combinations, the corresponding adsorption effect will decline.

[0161] In order to compare and determine the effect of the structural stabilizer in the adsorbent, the experiment in Table 3 below was designed.

[0162] Table 4 Exploration experiment of structural stabilizers in the adsorbent

[0163]

[0164] In Comparative Examples 5 and 6 in Table 4 above, 40 repeated adsorption experiments were carried out on the adsorbent prepared by this method. The final test results are shown in Table 2 and Figure 3 as shown. By comparing Example 4, Example 6 and Comparative Example 4, it can be found that the effect of adding MgO is the worst. At the same time, by comparing the adsorption effects of Comparative Example 5 and Comparative Example 6, it is found that even if the adsorbent with added MgO is reused 40 times, compared with Comparative Example 5 without added structural stabilizer, the adsorption effect of Comparative Example 6 is significantly relatively better and the structure of the adsorbent is more stable.

[0165] Finally, by comparing the adsorption effects of the adsorbent in Example 4 with that of the commercially available example, the adsorption effect of Example 4 is significantly better.

Claims

1. Preparation method of pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine, characterized in that, it comprises the following steps: Step a: Grind the binder into powder for standby, and the binder is kaolin; Step b: Mix 13X molecular sieve, binder, structure stabilizer and calcium compound in a certain proportion, and make spherical compound A after mixing; Step c: Pre-dry spherical compound A, then carry out roasting, water washing, drying and activation to obtain the adsorbent; In step b, the structure stabilizer is selected from Fe 2 O 3 ; in step b, the calcium compound is calcium oxide and calcium chloride; The content ratio of the calcium compound to the 13X molecular sieve in step b is 20 - 50 mmol Ca 2+ : 100 g of 13X molecular sieve, and the mass ratio of the kaolin, the structure stabilizer to the 13X molecular sieve is 0.15∶0.05∶5; The activation in step c is carried out in a rotary kiln. The atmosphere in the rotary kiln during the activation process is nitrogen, and the pressure is slightly positive pressure. The activation method is programmed temperature rise method. The temperature in the first stage rises from 300 °C to 450 °C, and the heating time is 2-4 hours. Then keep the temperature at 450 °C for 1 hour.

2. The preparation method of pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine according to claim 1, characterized in that, the spherical compound A in step b is prepared by adding water to 13X molecular sieve, kaolin, structure stabilizer and calcium compound in a ball mill.

3. The preparation method of pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine according to claim 1, characterized in that, the pre-drying temperature in step c is 65-85 °C, and the drying time is 3-4 hours; the roasting temperature is 600-700 °C, and the time is 3-5 hours; the water washing temperature is 85-95 °C, and the water washing time is 5 hours.

4. An adsorbent prepared by the method according to any one of claims 1-3.

5. Application of the adsorbent according to claim 4 in the pressure swing adsorption hydrogen extraction process for synthesizing morpholine, characterized in that, the adsorbent is filled in an adsorption tower. The adsorption tower is provided with an adsorbent packing area (1). The lower end of the adsorbent packing area (1) is provided with an adsorbent packing support (4). A vibration motor (3) is arranged on the adsorbent packing support (4). The vibration arm (2) of the vibration motor (3) extends upward into the adsorbent packing area (1).

6. Application of the adsorbent according to claim 5 in the pressure swing adsorption hydrogen extraction process for synthesizing morpholine, characterized in that, the adsorbent packing support (4) is densely provided with micropores (5). The micropores (5) on the adsorbent packing support (4) are composed of two circular holes with different apertures that are connected up and down. And the aperture of the circular hole on the side close to the adsorbent packing area (1) is smaller than the aperture of the circular hole on the side far from the adsorbent packing area (1).

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