CN116196890A - A kind of pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine and preparation method thereof - Google Patents

Abstract

The invention relates to the technical field of adsorbents, and specifically discloses a pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine and a preparation method thereof. The specific preparation method includes the following steps: step a: grinding the binder into powder for later use; step b: Mix 13X molecular sieves, binders, structural stabilizers and calcium compounds in a certain proportion, and make spherical compound A after mixing; step c: pre-dry spherical compound A, and then roast, wash, dry and activate to obtain the adsorbent . The pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine provided by the present invention has good adsorption effect and can withstand high concentration CO ₂ , and a structural stabilizer is added to the adsorbent, so that the prepared adsorbent has a stable structure and can withstand The impact of airflow scour, particle and bed vibration on the adsorbent, and finally, the preparation method of the adsorbent of the present invention is simple and easy for industrial production.

Description

A kind of pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine and preparation method thereof

The invention relates to the technical field of pressure swing adsorption, in particular to a pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine and a preparation method thereof.

Background technique

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

The adsorption amount of adsorbate on the adsorbent varies with the partial pressure of the adsorbate at a certain temperature, and this variation relationship can be described by the adsorption isotherm. In Figure 1, 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 stronger adsorption component than B. When the mixture of A and B is adsorbed at high pressure (assuming that the partial pressures of A and B are PA2 and PB2, respectively), it is desorbed and regenerated at low pressure (assuming that the partial pressures of A and B are both PA1 and PB1). When the adsorption reaches a certain stage, the two reach the adsorption equilibrium, and the adsorption amounts are q _A2 and q _B2 respectively, and q _A2 > q _B2 , so the content of A in the effluent airflow of the adsorption bed in the adsorption stage is less than that of B, which is B-rich airflow . When the adsorption reaches a certain level, 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 capacity of the adsorption bed for A and B is Δq _A = q _A2 -q _A1 and Δq _B = q _B2 -q _B1 respectively, the former is greater than the latter, so that in the desorption effluent gas, the components The content of A is greater than that of B. The adsorption bed achieves the separation of components A and B through the process of high pressure adsorption and low pressure desorption.

In the process of synthesizing morpholine, the function of pressure swing adsorption hydrogen extraction process is to separate H ₂ from CO, N ₂ , CH ₄ and other components to obtain high-purity H ₂ product gas. The process of hydrogen extraction by pressure swing adsorption adopts six-tower three-time pressure equalization process. CO, N ₂ and CH ₄ in the feed gas are adsorbed by the adsorbent, and the H ₂ that meets the product requirements is sent out of the adsorption tower as the adsorption tail gas and sent to the subsequent process. The adsorbed CO, N ₂ , CH ₄ are desorbed through forward, reverse and flushing methods, and the adsorbent is regenerated at the same time. Therefore, developing and preparing adsorbents that meet the needs of morpholine production is an important key point in the pressure swing adsorption hydrogen extraction process.

The PSA-H ₂ section of synthesizing morpholine generally uses CO, N ₂ and CH ₄ as the target adsorbates. When the adsorbent has no time to adsorb these substances, these substances will penetrate the adsorption tower bed and appear in the H ₂ product gas. , affecting the purity of the _H2 product gas. The process gas often contains not only the above three gases, but also other impurities, such as CO ₂ , but the adsorbent used in the H ₂ section has poor tolerance to CO ₂ gas, which is likely to cause poisoning of the adsorbent, thus Reduce the separation efficiency. When the impurity components of the feed gas change, especially when the CO ₂ content in the feed gas changes greatly, it may be necessary to adjust the device, and even stop the intake if necessary, which seriously affects the PSA-H ₂ section production efficiency.

The adsorbents filled in the adsorption tower usually include 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 such as water vapor, light hydrocarbons, and methanol. Molecular sieves are generally used together, and their main function is to separate components with relatively low boiling points such as CO ₂ , CH ₄ , and N ₂ , which are difficult to adsorb. Among them, 5A molecular sieves are commonly used for molecular sieves. At present, the activated carbon and molecular sieves filled in the adsorption tower of the pressure swing adsorption hydrogen extraction process, Its performance index has a significant impact on the hydrogen extraction effect. In the morpholine synthesis process, the automatic valves of the inlet and outlet airflows of the adsorption tower in the PSA-H ₂ section operate frequently. It is necessary to accurately control the opening and closing of the valves and the opening degree according to the time sequence. The pollution of the follow-up process or the requirements of filter cleaning require molecular sieve adsorbents with high stability.

Contents of the invention

The purpose of the present invention is to aim at the shortcomings of currently used adsorbents on the market, to provide a kind of _CO2 good tolerance, adsorbent stability high adsorbent for hydrogen extraction by pressure swing adsorption for the synthesis of morpholine, and the preparation of the adsorbent method.

A kind of preparation method of pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine, is characterized in that, comprises the steps:

Step a: Grinding the binder into powder for later use;

Step b: mixing 13X molecular sieves, binders, structural stabilizers and calcium compounds in a certain proportion, and making spherical compound A after mixing;

Step c: pre-drying the spherical compound A, followed by roasting, washing with water, drying and activating to obtain the adsorbent.

Further, the binder in step a is kaolin.

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

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

Further, the structural stabilizer in step b is MgO or Fe ₂ O ₃ .

Further, the content ratio of the calcium compound and the 13X molecular sieve in the step b is 20-50mmol Ca ⁺ : 100g13X molecular sieve, the content ratio of the kaolin, the structural stabilizer and the 13X molecular sieve is 0.15:0.05:5, and the adsorbent On a dry weight basis, the 13X molecular sieve content in the adsorbent is more than 90% by weight.

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

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

Further, the activation in step c 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 a temperature-programmed method, and the temperature in the first stage is from 300°C to 450°C. The heating time is 2-4 hours, and then the temperature is kept at 450° C. for 1 hour.

The present invention also provides an adsorbent prepared by any one of the above methods, the adsorbent is applied in the pressure swing adsorption hydrogen extraction process of synthesizing morpholine, the adsorbent is packed in an adsorption tower, and the adsorption tower is equipped with There is an adsorbent packing area, the lower end of the adsorbent packing area is provided with an adsorbent packing support, and a vibration motor is arranged on the adsorbent packing support, and the vibrating arm of the vibration motor extends upward to the adsorbent packing area;

Preferably, the adsorbent packing support is densely covered with micropores, and the micropores on the adsorbent packing support are composed of two connected upper and lower circular holes with different pore diameters, and the circular holes near the side of the adsorbent packing area The pore diameter of the pores is smaller than the pore diameter of the circular pores on the side remote from the adsorbent packing region.

The beneficial effects of the present invention are:

1, the synthetic morpholine provided by the present invention uses pressure swing adsorption to extract hydrogen adsorbent, in the synthetic morpholine process, owing to have used 13X molecular sieve material in the adsorbent preparation process, and has added calcium compound, double effect has strengthened adsorbent to The tolerance of _CO2 in the process gas, and the adsorption effect is better.

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 airflow erosion, particle and bed vibration on the adsorbent.

3. The preparation method of the pressure swing adsorption hydrogen extraction adsorbent for the synthesis of morpholine provided by the present invention is divided into 3 operation steps. Compared with the traditional impregnation method, the impregnation step is not required, the preparation method is simple, and the cost is saved And energy, and raw material source is extensive, easy industrial use.

Description of drawings

Figure 1 is the adsorption isotherms of A and B adsorbents;

Fig. 2 is the flow chart of pressure swing adsorption hydrogen extraction adsorption equipment;

Fig. 3 is the comparison result of the adsorption stability of the adsorbent prepared in Example 4, Comparative Example 4, Comparative Example 5 and Comparative Example 6;

Fig. 4 is the structural representation of the adsorption tower of embodiment 12 of the present invention;

Fig. 5 is a schematic cross-sectional structure diagram of an adsorbent packing bracket of an adsorption tower according to Example 12 of the present invention.

Detailed ways

Example 1

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

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

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 4 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect detection

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 81ml/g, the adsorption capacity of methane is 76.00ml/g, and the adsorption capacity of nitrogen is 70.06ml/g.

Example 2

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

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

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 4 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect detection

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 84ml/g, the adsorption capacity of methane is 71ml/g, and the adsorption capacity of nitrogen is 72.5ml/g.

Example 3

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

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

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet storage water is formed to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 2 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect test

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 83ml/g, the adsorption capacity of methane is 73.00ml/g, and the adsorption capacity of nitrogen is 70ml/g.

Example 4

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

Step b: Weigh 100g13X molecular sieve, 3g kaolin, 1gMgO, 20mmol calcium chloride and 12mmol calcium oxide, mix and add water in a ball mill to make spherical compound A;

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect detection

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 88ml/g, the adsorption capacity of methane is 76.5ml/g, and the adsorption capacity of nitrogen is 75ml/g.

Example 5

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

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

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect detection

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 82ml/g, the adsorption capacity of methane is 73.5ml/g, and the adsorption capacity of nitrogen is 70ml/g.

Example 6

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

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

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect detection

Measured by gravimetric method: the adsorbent prepared above is at 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 84ml/g, the adsorption capacity of methane is 73ml/g, and the adsorption capacity of nitrogen is 71ml/g.

Example 7

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

Step b: Weigh 100g13X molecular sieve, 3g kaolin, 1gMgO, 20mmol calcium chloride and 12mmol calcium hydroxide, mix and add water in a ball mill to make spherical compound A;

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect test

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 82ml/g, the adsorption capacity of methane is 71.5ml/g, and the adsorption capacity of nitrogen is 73.5ml/g.

Example 8

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

Step b: Weigh 100g13X molecular sieve, 3g kaolin, 1gMgO, 50mmol calcium chloride, mix and add water in a ball mill to make spherical compound A;

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect test

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 82ml/g, the adsorption capacity of methane is 71.5ml/g, and the adsorption capacity of nitrogen is 73.5ml/g.

Example 9

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

Step b: Weigh 100g13X molecular sieve, 3g kaolin, 1gMgO, 50mmol calcium oxide, mix and add water in a ball mill to make spherical compound A;

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect test

Measured by gravimetric method: the adsorbent prepared above is at 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 82ml/g, the adsorption capacity of methane is 70.5ml/g, and the adsorption capacity of nitrogen is 74.5ml/g.

Example 10

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

Step b: Weigh 100g13X molecular sieve, 3g kaolin, 1gMgO, 50mmol calcium hydroxide, mix and add water in a ball mill to make spherical compound A;

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect detection

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 80ml/g, the adsorption capacity of methane is 70ml/g, and the adsorption capacity of nitrogen is 70.5ml/g.

Example 11

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

Step b: Weigh 100g13X molecular sieve, 3g kaolin, 1gMgO, 20mmol calcium oxide and 12mmol calcium hydroxide, mix and add water in a ball mill to make spherical compound A;

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect test

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 83ml/g, the adsorption capacity of methane is 73ml/g, and the adsorption capacity of nitrogen is 71.5ml/g.

Example 12

The prepared adsorbent is loaded in the adsorption tower. In the past, the adsorbent often had the problem of insufficient filling or false filling during the filling process, especially for the adsorbent used in the pressure swing adsorption hydrogen extraction process. During the process of pressure, parallel discharge, reverse discharge, flushing, and boosting, due to the large distance between the adsorbents, under the periodic washing and vibration of the reciprocating air flow, the adsorbents will wriggle, roll, jump, collide and even boil, resulting in The adsorbent is pulverized a little. The pulverization of the adsorbent makes the gaps in the adsorption tower bigger and bigger, and the increase of the gaps creates conditions for greater beating. This is a vicious cycle. Over time, large-scale pulverization of the adsorbent occurs, which seriously affects the adsorption efficiency of the adsorbent. .

For this reason, the adsorption tower of present embodiment adsorbent packing is provided with adsorbent packing area 1, and the lower end adsorbent packing support 4 of described adsorbent packing area 1, and described adsorbent packing support 4 is provided with vibrating motor 3, so The vibrating arm 2 of the vibrating motor 3 extends upwards to the adsorbent filling area 1. When the operator is loading the adsorbent packing, during the filling process, the vibrating arm 2 is driven by the vibrating motor 3 to vibrate, so that the adsorbent is compacted and packed, and the filling process is completed. During the process, according to the actual situation, it is vibrated several times to complete the filling of the adsorbent.

The adsorbent packing support 4 is densely covered with micropores 5, and the micropores 5 are composed of two circular holes with different apertures connected up and down on the adsorbent packing support 4, and the circular holes near the side of the adsorbent The pore diameter is smaller than the pore diameter of the circular hole on the side away from the adsorbent. This structure ensures that the adsorbent will not fall from the circular hole, and at the same time ensures that the process gas quickly enters the adsorbent packing area 1. When the adsorption tower is working, the process gas enters the adsorption tower and enters the adsorbent packing area 1 through the micropores 5 of the adsorbent packing support 4, thereby completing the adsorption of the gas.

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

Comparative example 1

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

Step b: Weigh 85g13X molecular sieve, 2.55g kaolin, 0.85gMgO, 12mmol calcium oxide and 20mmol calcium chloride, mix and add water in a ball mill to make spherical compound A;

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect detection

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

Comparative example 2

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

Step b: Weigh 100g13X molecular sieve, 3g kaolin, 1gMgO, 60mmol calcium chloride, mix and add water in a ball mill to make spherical compound A;

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect detection

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 74ml/g, the adsorption capacity of methane is 71.5ml/g, and the adsorption capacity of nitrogen is 72ml/g.

Comparative example 3

Sorbent preparation

Step a: Grinding blocky kaolin into powder for later use;

Step b: Weigh 100g13X molecular sieve, 3g kaolin, 1gMgO, 15mmol calcium chloride, mix and add water in a ball mill to make spherical compound A;

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, and the pre-dried spherical compound A is baked in a rotary kiln at 600°C for 5 hours to remove the structural water and Wet water is molded to achieve solid ion exchange, and then soaked in hot water at a constant temperature of 90°C for 5 hours, and finally enters the rotary kiln for activation. Under nitrogen atmosphere and slight positive pressure, the temperature is programmed from 300°C to 450°C for 3 hours. After that, keep the temperature at 450° C. for 1 hour to increase the thermal stability after artificial, and complete the preparation of the adsorbent.

Sorbent effect detection

Measured by gravimetric method: the adsorbent prepared above has an adsorption capacity of 71ml/g for carbon dioxide, 70.5ml/g for methane, and 69ml/g for nitrogen under 1 standard atmospheric pressure and 25°C.

Comparative example 4

The preparation of the adsorbent is compared with that in Example 4, only the structure stabilizer is not added, and other preparation steps remain unchanged, and the adsorbent is prepared.

Sorbent effect test

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 70ml/g, the adsorption capacity of methane is 66.5ml/g, and the adsorption capacity of nitrogen is 68ml/g.

Comparative example 5

The preparation of the adsorbent is compared with that in Example 4, only the structure stabilizer is not added, and other preparation steps remain unchanged, and the adsorbent is prepared.

Sorbent effect test

Repeat the use of the adsorbent obtained by this preparation method for 40 times, and measure it by gravimetric method: the adsorption amount of carbon dioxide is 50ml/g, and the adsorption amount of methane is 52.5ml/g at 25°C for the 40th detection of the adsorbent. g, the adsorption capacity of nitrogen is 50ml/g.

Comparative example 6

Sorbent preparation

Compared with Example 4, the preparation steps are unchanged, and the adsorbent is prepared.

Sorbent effect detection

Repeat the use of the adsorbent obtained by this preparation method for 40 times, and measure it by gravimetric method: the adsorption amount of carbon dioxide is 71ml/g, and the adsorption amount of methane is 65.5ml/g at 25°C for the 40th detection of the adsorbent at 1 standard atmospheric pressure. g, the adsorption capacity of nitrogen is 65ml/g.

The adsorption stability of the adsorbents of Comparative Example 5 and Comparative Example 6 was tested on a NETZSCH thermogravimetric analyzer of NETZSCH, and the results are shown in FIG. 3 .

Commercial example

Purchase the molecular sieve adsorbent sold on the market, the adsorbent sold by a manufacturer in Beijing, the adsorbent is 5A molecular sieve adsorbent.

Sorbent effect detection

Measured by gravimetric method: the adsorbent prepared above is under 1 standard atmospheric pressure and at 25°C, the adsorption capacity of carbon dioxide is 65ml/g, the adsorption capacity of methane is 72.5ml/g, and the adsorption capacity of nitrogen is 71ml/g.

The adsorption effects of the PSA hydrogen extraction adsorbents for synthetic morpholine prepared in the above examples and comparative examples are summarized in Table 1 and Table 2 below.

Sorbent preparation parameter in each embodiment of table 1 and comparative example

The adsorption effect of adsorbent in each embodiment of table 2 and comparative example

In order to compare and determine the ratio of the calcium compound in the adsorbent, the experiments in Table 3 below were designed.

Table 3 Exploration experiment of calcium compound in adsorbent

Through the experimental design in the above table 3, combined with the adsorption effect of the corresponding adsorbent in table 2, it is not difficult to conclude that when the calcium compound is a combination of calcium chloride and calcium oxide, the adsorption effect of the prepared adsorbent is the best , especially the adsorption effect of the adsorbent on carbon dioxide, so the adsorbent prepared by calcium chloride and calcium oxide as calcium compound can better tolerate the carbon dioxide in the process gas, when using a single calcium compound or other combinations , the corresponding adsorption effect will decrease.

In order to compare and determine the effect of the structural stabilizer in the adsorbent, the experiments in Table 3 below were designed.

Table 4 Structural stabilizer exploration experiment in adsorbent

In Comparative Example 5 and Comparative Example 6 in Table 4 above, 40 repeated adsorption experiments were carried out on the adsorbent prepared by this method, and the final detection results are shown in Table 2 and FIG. 3 . By comparing Example 4, Example 6 and Comparative Example 4, it can be found that the effect of adding MgO is the last, while comparing the adsorption effects of Comparative Example 5 and Comparative Example 6, it is found that even if the adsorbent with MgO is used repeatedly 40 times, compared with no The adsorption effect of Comparative Example 5 and Comparative Example 6 with the addition of a structural stabilizer is relatively better, and the structure of the adsorbent is more stable.

Finally, compared with the adsorption effect of the adsorbent of the commercially available example, the adsorption effect of embodiment 4 is obviously better.

Claims (10)

1. The preparation method of the pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine is characterized by comprising the following steps:

step a: grinding the binder into powder for later use;

step b: mixing a 13X molecular sieve, a binder, a structural stabilizer and a calcium compound according to a certain proportion, and preparing a spherical compound A after mixing;

step c: pre-drying the spherical compound A, and then roasting, washing, drying and activating to obtain the adsorbent.

2. The method for preparing pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine as claimed in claim 1, wherein the binder in the first step is kaolin.

3. The method for producing a pressure swing adsorption hydrogen extraction adsorbent for morpholine synthesis according to claim 1, wherein in said step b, calcium is selected from at least one of calcium oxide, calcium chloride and calcium hydroxide.

4. A process for the preparation of a pressure swing adsorption hydrogen extraction adsorbent for the synthesis of morpholine according to claim 1 or 3, wherein the calcium compound in step b is calcium oxide and calcium chloride.

5. The process for preparing pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine as claimed in claim 1, wherein said structure stabilizer in said step b is selected from MgO or Fe ₂ O ₃ 。

6. The method for producing pressure swing adsorption hydrogen extraction adsorbent for morpholine synthesis as claimed in claim 1, wherein the content ratio of calcium compound to 13X molecular sieve in said step b is 20-50 mmola ca ⁺ :100g of 13X molecular sieve, wherein the content ratio of the kaolin, the structure stabilizer and the 13X molecular sieve is 0.15:0.05: 5, the 13X molecular sieve content in the adsorbent is more than 90% by weight based on the dry weight of the adsorbent.

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

8. The process for preparing pressure swing adsorption hydrogen adsorbent for morpholine synthesis according to claim 1, wherein the pre-drying temperature in step b is 65-85 ℃ and the drying time is 3-4 hours; the roasting temperature is 600-700 ℃ and the time is 3-5 hours; the water washing temperature is 85-95 ℃ and the water washing time is 5 hours.

9. The method for preparing pressure swing adsorption hydrogen extraction adsorbent for synthesizing morpholine according to claim 1, wherein the activation in step c is performed in a rotary kiln, the atmosphere in the rotary kiln is nitrogen during the activation, the pressure is micro positive pressure, the activation method is a temperature programming method, the temperature in the first stage is 300 ℃ to 450 ℃, the temperature raising time is 2-4 hours, and then the temperature is kept at 450 ℃ for 1 hour.

10. The adsorbent prepared by the method according to any one of claims 1-9, wherein the adsorbent is applied to a pressure swing adsorption hydrogen extraction process of synthesizing morpholine, the adsorbent is filled in an adsorption tower, the adsorption tower is provided with an adsorbent filler zone (1), the lower end of the adsorbent filler zone (1) is provided with an adsorbent filler support (4), the adsorbent filler support (4) is provided with a vibrating motor (3), and a vibrating arm (2) of the vibrating motor (3) extends upwards to the adsorbent filler zone (1);

preferably, the adsorbent filler support (4) is densely provided with micropores (5), the micropores (5) are formed by two circular holes with different diameters which are communicated up and down on the adsorbent filler support (4), and the pore diameter of the circular hole at one side close to the adsorbent filler region (1) is smaller than that of the circular hole at one side far away from the adsorbent filler region (1).

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