Closed sampling purge gas adsorption canister and adsorption method

Abstract

The present application relates to the technical field of purging gas adsorption, and provides a closed sampling purging gas adsorption tank, which comprises a tank body and a containing cavity formed by surrounding the tank body, a supporting plate sealingly arranged in the containing cavity, a liquid collecting cavity formed by the supporting plate and the tank body below the supporting plate, a purging gas adsorption cavity formed by the supporting plate and the tank body above the supporting plate, a gas flow channel arranged on the supporting plate, a sponge arranged on the supporting plate, a purging gas inlet pipeline and a purging gas outlet pipeline penetrating through the tank body, a port of the purging gas inlet pipeline being arranged below the supporting plate, and a port of the purging gas outlet pipeline being arranged above the sponge, wherein the sponge comprises an oil-absorbing sponge. The purging gas is adsorbed by using the adsorption tank, the replacement period of the adsorption material is long, the adsorption ratio is large, the condensable gas in the purging gas can be effectively condensed, and the pollution of the purging gas to the environment and the harm of the purging gas to human health are prevented.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of purging gas adsorption technology, in particular to a closed sampling purging gas adsorption tank and an adsorption method. BACKGROUND

[0002] In the petrochemical production process, it is often necessary to collect samples of flammable, explosive and even toxic and harmful gases to monitor the production process and product quality. In order to prevent these gases from leaking into the atmosphere, the collection work must be carried out in a closed sampler. The application of the closed sampler effectively prevents the occurrence of dangerous behavior during sampling, prevents occupational disease risk, and protects life and property safety; at the same time, the closed sampler reduces the possibility of sample volatilization and pollution, making the test analysis more accurate and reliable, and in addition, it blocks the channel of sample discharge to the atmosphere, thereby reducing the pollution of the atmospheric environment.

[0003] Before and after sampling, the closed sampler needs to be purged with purging gas to prevent the pollution of the sample and the residual gas in the pipeline. For the sampling of condensable gas, an adsorption device filled with adsorbent is generally used for adsorption. At present, the commonly used adsorption device is an activated carbon adsorption device. However, the activated carbon adsorption device has a low adsorption ratio, a short replacement cycle, and a series of shortcomings such as easy sticking to the wall, which limits its application in this field.

[0004] Therefore, there is an urgent need for a new closed sampler purging gas adsorption device. SUMMARY

[0005] The purpose of the present application is to overcome the difficulty that the prior art cannot realize efficient and simple recovery of purging gas of a closed sampler, and to provide a closed sampling purging gas adsorption tank. The adsorption tank is used to adsorb purging gas, the replacement cycle of the adsorption material is long, the adsorption ratio is large, the condensable gas in the purging gas can be effectively condensed, and the pollution of the purging gas to the environment and the harm to human health are prevented.

[0006] In order to achieve the above-mentioned purpose, the present application provides a closed sampling purging gas adsorption tank, which comprises:

[0007] a tank body and a containing cavity formed around the tank body;

[0008] a supporting plate sealingly arranged in the containing cavity, a liquid collecting cavity being formed below the supporting plate and the tank body, a purging gas adsorption cavity being formed above the supporting plate and the tank body, and a gas flow channel being arranged on the supporting plate;

[0009] a sponge arranged on the supporting plate, used to contact the purging gas and condense the condensable gas in the purging gas into liquid droplets;

[0010] a purging gas inlet pipeline and a purging gas outlet pipeline penetrating through the tank body, a port of the purging gas inlet pipeline being arranged below the supporting plate, and a port of the purging gas outlet pipeline being arranged above the sponge.

[0011] The sponge comprises an oil-absorbing sponge, wherein the oil-absorbing sponge comprises a three-dimensional porous polymer matrix and a thermosetting resin coated on the three-dimensional porous polymer matrix; the oil-absorbing sponge has a saturated adsorption capacity of oil products of not less than 30 g / g; and the saturated adsorption capacity of the oil-absorbing sponge to oil products is still not less than 30 g / g after 30 cycles of adsorption-desorption.

[0012] The second aspect of the present application provides a closed sampling purge gas adsorption method, which comprises:

[0013] The purge gas is input into the liquid collection chamber through the purge gas inlet pipeline, and the purge gas contacts the sponge in the purge gas adsorption chamber through the supporting plate, and the condensable gas in the purge gas condenses into droplets, and the droplets drop into the liquid collection chamber under the action of gravity;

[0014] The remaining purge gas is discharged through the purge gas outlet pipeline.

[0015] Through the above technical solution, the closed sampling purge gas adsorption tank provided by the present application comprises the oil-absorbing sponge provided by the present application, and the oil-absorbing sponge has super-hydrophobic and super-oleophilic properties. The super-oleophilic property of the oil-absorbing sponge material enables the condensable gas carried in the purge gas to be adsorbed and enriched when contacting the sponge skeleton, and to condense into oil droplets. When the adsorption force of the sponge skeleton to the oil droplets is less than the gravity, the oil droplets slide into the liquid collection chamber, and periodic oil discharge can be achieved.

[0016] In the present application, the oil-absorbing sponge has good condensation effect on the condensable gas in the purge gas, and the oil and gas adsorption rate is greater than 90%, and the passing rate of the purge gas is 100%. At the same time, the oil-absorbing sponge has a flame retardant level of V-0, and has very excellent flame retardant properties, which provides safety protection for the sampling link of the petrochemical industry. In addition, the oil-absorbing sponge still has condensation effect on high-temperature oil and gas, and has wide application conditions, and unexpected technical effects are achieved. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a structure schematic diagram of a closed sampler purge gas adsorption tank provided by a preferred embodiment of the present application;

[0018] Figure 2 is a scanning electron microscope (SEM) image of the oil-absorbing sponge prepared in Preparation Example 1;

[0019] Figure 3 is a scanning electron microscope (SEM) image of the oil-absorbing sponge prepared in Preparation Example 1 after 30 cycles;

[0020] Figure 4 is a scanning electron microscope (SEM) image of the porous melamine-formaldehyde sponge matrix in Preparation Example 1;

[0021] Figure 5 is a scanning electron microscope (SEM) image of the oil absorption sponge prepared in Preparation Example 8;

[0022] Figure 6 is a scanning electron microscope (SEM) image of the oil absorption sponge prepared in Preparation Example 8 after 30 cycles.

[0023] BRIEF DESCRIPTION OF DRAWINGS

[0024] 1 - tank body 2 - tray

[0025] 3 - sponge 4 - purge gas inlet line

[0026] 5 - purge gas outlet line 6 - liquid discharge valve DETAILED DESCRIPTION

[0027] The endpoints of the ranges and any values described herein are not limited to the precise values stated. The endpoints of the ranges and any values should be understood to be approximate. The exact numerical values should be considered to be an approximation within the context of the range or value. The endpoints of the ranges of values and the values within the range should be combined with one another to form new ranges of values that are not expressly mentioned.

[0028] In the present invention, unless otherwise stated, the orientation words such as "upper", "lower", "left", "right" generally refer to the upper, lower, left, right shown in the drawings; "inner", "outer" refer to the inner, outer relative to the contour of the parts themselves.

[0029] The first aspect of the present invention provides a closed sampling purge gas adsorption tank, the adsorption tank comprising:

[0030] a tank body 1 and a containing cavity formed around the tank body 1 ;

[0031] a tray 2 sealingly arranged in the containing cavity, a liquid collecting cavity being formed below the tray 2 and the tank body 1, a purge gas adsorption cavity being formed above the tray 2 and the tank body 1, the tray 2 being provided with a gas flow channel;

[0032] a sponge 3 arranged on the tray 2, for contacting with the purge gas and condensing the condensable gas in the purge gas into liquid droplets;

[0033] a purge gas inlet line 4 and a purge gas outlet line 5 penetrating through the tank body 1, a port of the purge gas inlet line 4 being arranged below the tray 2, a port of the purge gas outlet line 5 being arranged above the sponge 3;

[0034] The sponge 3 comprises an oil absorption sponge, which comprises a three-dimensional porous polymer matrix and a thermosetting resin coated on the three-dimensional porous polymer matrix; the oil absorption sponge has a saturated adsorption capacity of oil products of not less than 30 g / g; and the saturated adsorption capacity of the oil absorption sponge for oil products is still not less than 30 g / g after 30 times of adsorption-desorption cycle use. The closed sampling purge gas adsorption tank comprises the oil absorption sponge according to the present application, and the oil absorption sponge has super-hydrophobic and super-oleophilic properties. The super-oleophilic properties of the oil absorption sponge material enable the condensable gas carried in the purge gas to be adsorbed and enriched when contacting the sponge skeleton, and to be condensed into oil droplets. When the adsorption force of the sponge skeleton on the oil droplets is less than the gravity, the oil droplets slide into the liquid collection cavity, and the oil can be periodically drained.

[0035] According to a preferred embodiment of the present application, the tank body 1 is further provided with a liquid drainage valve 6 at the bottom for draining the collected liquid droplets.

[0036] According to a preferred embodiment of the present application, the supporting plate 2 is provided with an opening with a hole diameter of 5-20 mm.

[0037] In the present application, the sponge is laid on the supporting plate 2, and the diameter of the sponge is slightly larger than the inner diameter of the tank body, so that the sponge can fully fill the accommodation cavity and prevent oil and gas from overflowing; the filling thickness of the sponge is 1 / 2-2 / 3 of the height of the tank body above the supporting plate 2. The lower surface of the sponge is tightly attached to the supporting plate. The above filling conditions are all conducive to the full adsorption of the purge gas.

[0038] The oil absorption sponge according to the present application has super-hydrophobic and super-oleophilic properties on the basis of maintaining the high resilience and high porosity of the original three-dimensional porous polymer matrix, and has good resilience and strong adsorption capacity for oil products.

[0039] According to a preferred embodiment of the present application, the mass of the thermosetting resin accounts for 0.5-5% of the total mass of the sponge, preferably 2-3%.

[0040] According to a preferred embodiment of the present application, the saturated adsorption capacity of the oil absorption sponge for oil products is 30-50 g / g.

[0041] The oil absorption sponge according to the present application has strong selectivity for oil products in oily sewage, large adsorption capacity for oil products and recyclable use, and the adsorption capacity does not substantially decrease even after 30 times of cycle use. According to a preferred embodiment of the present application, the saturated adsorption capacity of the oil absorption sponge for oil products is still 30-50 g / g after 30 times of desorption-adsorption cycle use.

[0042] In the present application, the thermosetting resin can be selected from a wide range, and the conventional thermosetting resin in the art can meet the requirements of the present application. According to a preferred embodiment of the present application, the thermosetting resin is selected from at least one of phenolic resin, epoxy resin, urea-formaldehyde resin, unsaturated polyester resin and silicone resin; preferably at least one of phenolic resin, epoxy resin and silicone resin.

[0043] In the present application, the three-dimensional porous polymer matrix can have a through-hole structure inside and a porosity greater than 70%. According to a preferred embodiment of the present application, the three-dimensional porous polymer matrix is selected from at least one of melamine-formaldehyde sponge, polyurethane sponge and ethylene-vinyl acetate sponge, preferably melamine-formaldehyde sponge.

[0044] In the present application, the pore size of the oil-absorbing sponge can be selected from a wide range. According to a preferred embodiment of the present application, the pore size of the oil-absorbing sponge is 10-500 μm, preferably 100-400 μm.

[0045] In the present application, the porosity of the oil-absorbing sponge can be selected from a wide range. According to a preferred embodiment of the present application, the porosity of the oil-absorbing sponge is greater than or equal to 60%, preferably greater than or equal to 90%.

[0046] The oil-absorbing sponge according to the present application has superhydrophobic and superoleophilic properties. According to a preferred embodiment of the present application, the static planar contact angle of the oil-absorbing sponge surface to water in air is greater than 135°; preferably greater than 145°.

[0047] The oil-absorbing sponge according to the present application has superhydrophobic and superoleophilic properties. According to a preferred embodiment of the present application, the static contact angle of the oil-absorbing sponge surface to white oil is < 30°; preferably 0-20°; more preferably 0°.

[0048] The oil-absorbing sponge according to the present application also has flame retardant properties. According to a preferred embodiment of the present application, the UL94 vertical burning test grade of the oil-absorbing sponge is V-2 or above, preferably V-1 or above; more preferably V-0.

[0049] The oil-absorbing sponge having the aforementioned features of the present application can achieve the purpose of the present application, and there is no special requirement for its preparation method. According to a preferred embodiment of the present application, the second aspect of the present application provides a preparation method of the oil-absorbing sponge according to the present application, which comprises:

[0050] The solution containing thermosetting resin prepolymer and curing agent is dispersed into the three-dimensional porous polymer matrix, and the oil absorption sponge is obtained by curing under vacuum condition. According to the preparation method of the present application, the solution containing thermosetting resin prepolymer and curing agent is dispersed (for example, extrusion absorption dispersion, spray absorption dispersion) into the three-dimensional porous polymer matrix, and then vacuum heating curing is carried out, so that the thermosetting resin can be cured on the three-dimensional porous polymer matrix while maintaining the high resilience and high porosity of the original three-dimensional porous polymer matrix.

[0051] In the present application, the dispersion method of the solution containing thermosetting resin prepolymer and curing agent into the three-dimensional porous polymer matrix is not particularly limited, as long as it can be uniformly dispersed. According to a preferred embodiment of the present application, the dispersion method is extrusion absorption dispersion, spray absorption dispersion, and preferably extrusion absorption dispersion.

[0052] In the present application, extrusion absorption dispersion refers to extruding the three-dimensional porous polymer matrix, placing it in the solution containing thermosetting resin prepolymer and curing agent, absorbing and recovering to the original appearance, and then extruding a certain proportion to discharge the excess solution and make it uniformly dispersed.

[0053] In the present application, spray absorption dispersion refers to uniformly dispersing a certain amount of thermosetting resin prepolymer and curing agent solution onto the surface of the three-dimensional porous polymer matrix in the form of spray, waiting for absorption, and then heating and curing.

[0054] In the present application, the curing pressure can be selected in a wide range. According to a preferred embodiment of the present application, the pressure is 0-10 kPa, and preferably 3-5 kPa.

[0055] In the present application, the curing conditions can be selected in a wide range. According to a preferred embodiment of the present application, the curing conditions include: the temperature is 80-200℃, and preferably 100-180℃; the curing time can be reasonably adjusted according to actual needs, and preferably the time is 5-120 min, and more preferably 20-100 min.

[0056] According to a preferred embodiment of the present application, the preparation method of the oil absorption sponge comprises:

[0057] (1) dispersing the solution containing thermosetting resin prepolymer and curing agent into the three-dimensional porous polymer matrix, and pre-curing under the first vacuum condition;

[0058] (2) dispersing the solution containing thermosetting resin prepolymer and curing agent into the product obtained in step (1), and curing under the second vacuum condition;

[0059] The first vacuum condition and the second vacuum condition each include: the pressure is 0-10 kPa;

[0060] The pre-curing condition includes a temperature of 80-120℃.

[0061] The curing condition includes a temperature of 140-180℃.

[0062] In the present application, the pre-curing of the thermosetting resin prepolymer makes the sponge temperature uniform, the internal thermosetting resin reaches the gel state, and is attached to the three-dimensional porous polymer matrix skeleton. The vacuum condition is conducive to the gas discharge of the thermosetting resin in the gel state, and better combines with the sponge skeleton. Then the solution containing the thermosetting resin prepolymer and the curing agent is dispersed on the three-dimensional porous polymer matrix containing the gel state thermosetting resin, and the oil absorption sponge is obtained by curing. This is conducive to the uniform distribution of the thermosetting resin on the sponge skeleton, thereby maintaining the elasticity of the three-dimensional porous polymer matrix and improving the cyclic use performance of the oil absorption sponge. The adsorption capacity does not attenuate substantially after 30 cycles of use.

[0063] According to a preferred embodiment of the present application, in step (1), the gel state thermosetting resin accounts for 0.5-1% of the total mass of the sponge, which is conducive to further maintaining the elasticity of the three-dimensional porous polymer matrix and improving the cyclic use performance of the oil absorption sponge.

[0064] In the present application, the pre-curing time in step (1) is not particularly required, and can be reasonably adjusted according to actual needs, as long as the thermosetting resin prepolymer forms a gel state thermosetting resin in the three-dimensional porous polymer matrix. According to a preferred embodiment of the present application, the pre-curing time is 40-90 min.

[0065] In the present application, the curing time in step (2) is 20-100 min.

[0066] According to a preferred embodiment of the present application, the mass concentration of the thermosetting resin prepolymer in the solution containing the thermosetting resin prepolymer and the curing agent is 0.02-0.6 g / mL, preferably 0.03-0.5 g / mL, and more preferably 0.05-0.3 g / mL.

[0067] According to a preferred embodiment of the present application, the mass of the curing agent in the solution containing the thermosetting resin prepolymer and the curing agent accounts for 1-10% of the mass of the thermosetting resin prepolymer; and preferably 5-10%.

[0068] In the present application, the solvent in the solution containing the thermosetting resin prepolymer and the curing agent has a wide selection range, as long as it can dissolve the thermosetting resin prepolymer and the curing agent. According to a preferred embodiment of the present application, the solvent in the solution containing the thermosetting resin prepolymer and the curing agent is selected from at least one of water, C1-C4 alcohol and C1-C4 ketone; and is preferably ethanol and / or acetone.

[0069] In the present application, the optional range of the curing agent in the solution containing the thermosetting resin prepolymer and the curing agent is wide, as long as the curing agent can form the thermosetting resin with the thermosetting resin prepolymer, according to a preferred embodiment of the present application, the curing agent is selected from at least one of organic acid, acid anhydride, boron trifluoride, aliphatic polyamine and aromatic polyamine; preferably at least one of benzene sulfonic acid, hexamethylenetetramine and m-phenylenediamine.

[0070] The second aspect of the present application provides a closed sampling purge gas adsorption method, which comprises:

[0071] The purge gas is input into the liquid collecting cavity through the purge gas inlet pipeline 4, the purge gas contacts the sponge 3 in the purge gas adsorption cavity through the supporting plate 2, the condensable gas in the purge gas is condensed into liquid droplets, and the liquid droplets drop into the liquid collecting cavity under the action of gravity;

[0072] The remaining purge gas is discharged through the purge gas outlet pipeline 5. By using the adsorption method of the present application, the oil-absorbing sponge has good condensation effect on the condensable gas in the purge gas, the oil and gas adsorption rate is greater than 90%, and the through rate of the purge gas reaches 100%.

[0073] In the present application, the source and type of the purge gas can be selected from a wide range, according to a preferred embodiment of the present application, the purge gas comes from a PX device, and the purge gas contains toluene 0-10%, p-xylene 0-20% and nitrogen 70-98% by volume fraction.

[0074] In the present application, the optional range of the purge gas adsorption condition is wide, according to a preferred embodiment of the present application, the adsorption condition includes that the adsorption temperature is-20-40℃.

[0075] According to a preferred embodiment of the present application, the liquid droplets collected in the liquid collecting cavity are discharged through the liquid discharge valve 7.

[0076] The present application will be described in detail through the following examples.

[0077] In the following examples, the structure diagram of the adsorption tank is as shown in the figure, the adsorption tank comprises: Figure 1 The adsorption tank comprises:

[0078] The tank body 1 and the containing cavity formed by surrounding the tank body 1;

[0079] The supporting plate 2 is sealingly arranged in the containing cavity, the supporting plate 2 below forms a liquid collecting cavity with the tank body 1, the supporting plate 2 above forms a purge gas adsorption cavity with the tank body 1, and the supporting plate 2 is provided with an opening, the aperture of the opening is 10mm;

[0080] The sponge 3 is arranged on the supporting plate 2 and used for contacting the purge gas to condense the condensable gas in the purge gas into liquid droplets;

[0081] A purge gas inlet line 4 and a purge gas outlet line 5 are provided through the tank body 1, the port of the purge gas inlet line 4 is arranged below the supporting plate 2, and the port of the purge gas outlet line 5 is arranged above the sponge 3;

[0082] A liquid discharge valve 6 is arranged at the bottom of the tank body 1 for discharging the collected liquid drops.

[0083] In the following examples, the vertical burning test level is tested according to the UL94 flame retardant test method.

[0084] In the following test examples, the saturated oil phase adsorption capacity and the saturated oil phase adsorption capacity after 30 cycles are tested by the following steps: weighing the mass m1 of the sponge to be tested, placing it in a beaker containing 200 mL of toluene, weighing the mass m2 of the sponge after adsorbing the saturated oil phase, and the saturated oil phase adsorption capacity (Ф) is Ф = m1 / m2. 2。 The test of the saturated oil phase adsorption capacity after 30 cycles first saturates the sponge with toluene and mechanically squeezes it to natural dripping of the oil phase, which is repeated 30 times, and then the test steps are the same as those for the saturated oil phase adsorption capacity.

[0085] In the following examples, the water contact angle parameter is measured by the EASY DROP contact angle tester of KRUSS Company in Germany, the measurement range is 1-180°, the resolution is ±0.1°, the static contact angle measurement mode is used, and a water droplet or a white oil droplet with a fixed volume of 2 μL is dropped on the sponge each time, the initial contact angle calculated is taken as the contact angle measurement value of the surface of the sponge, and the average value is calculated by measuring 6 times in parallel.

[0086] In the following examples, the oil gas adsorption rate of the purge gas is tested by the following method: the test temperature (T) is set to 35°C, and the PX device closed sampler is taken as an example. After sampling is completed, the sampling gas fills the same length of pipeline. Nitrogen is used as the purge gas for blowing, the total mass of the condensable gas in the sampling gas is (0.05*n) g after n times of blowing, and the weight gain m of the adsorption tank of the purge gas is recorded.

[0087] The oil gas adsorption rate (η) is η = m / (0.05*n).

[0088] In the following examples, the porosity of the porous melamine-formaldehyde sponge matrix (Xuxian Industry) is 95%, and the average pore size is 100 μm.

[0089] The porosity of the porous melamine-formaldehyde sponge matrix (Beiyou Building Materials) is 96%, and the average pore size is 250 μm.

[0090] Preparation Example 1

[0091] (1) 10 g of phenolic resin prepolymer solution (Meisheng Chemical Plasticization) and 1 g of hexamethylenetetramine were dissolved in 200 mL of ethanol, and the solution was stirred thoroughly to make it clear and transparent;

[0092] (2) Take 200*200*150mm porous melamine-formaldehyde sponge matrix (Xuexian Industry), and disperse the above solution into the sponge by extrusion dispersion method, so that the curing agent solution uniformly infiltrates the sponge. The sponge after extrusion is placed in a 180℃, 3kPa vacuum oven for curing for 20min, to obtain oil absorption sponge S1.

[0093] In the oil absorption sponge S1, the mass of phenolic resin accounts for 2% of the total mass of the oil absorption sponge; the average pore size of the oil absorption sponge S1 is 100μm, the porosity is 95%, the open porosity is 98%, the vertical combustion grade is V-0, the contact angle with white oil is 0°, and the contact angle with water is 152.3°; the saturated oil phase adsorption capacity is 40g / g; the saturated oil phase adsorption capacity after 30 cycles is 38g / g.

[0094] The sponge is subjected to the test of saturated oil phase adsorption capacity, oil phase removal rate and oil phase selective adsorption rate after 30 cycles according to the test requirements, and the results are shown in Table 1.

[0095] The SEM image of the oil absorption sponge S1 is shown in Figure 2 , compared with the melamine-formaldehyde sponge matrix (SEM image as shown in Figure 4 ), the size of the porous framework of the oil absorption sponge is slightly larger than that of the unmodified framework, which indicates that the phenolic resin is uniformly cured on the surface of the porous melamine-formaldehyde sponge matrix framework, has a through hole, so that the oil absorption sponge has strong selectivity for oil in oil-containing wastewater and large adsorption capacity for oil.

[0096] Figure 3 The SEM image of the oil absorption sponge S1 after 30 cycles is basically unchanged compared with Figure 2 , so that the adsorption capacity of the oil absorption sponge does not decay basically under the condition of 30 cycles.

[0097] Preparation Example 2

[0098] (1) Take 10g of phenolic resin prepolymer solution (Meisheng Chemical Plasticization) and 0.3g of hexamethylenetetramine and 0.2g of m-xylylenediamine dissolved in 200mL of ethanol, and stir well to make the solution clear and transparent.

[0099] (2) Take 200*200*150mm porous melamine-formaldehyde sponge matrix (Xuexian Industry), and disperse the above solution into the sponge by extrusion dispersion method, so that the curing agent solution uniformly infiltrates the sponge. The sponge after extrusion is placed in a 180℃, 3kPa vacuum oven for curing for 20min, to obtain oil absorption sponge S1.

[0100] The phenolic resin accounts for 3% of the total mass of the sponge S2. The average pore size of the oil absorption sponge S2 is 100 μm, the porosity is 95%, the open porosity is 98%, the vertical burning level is V-1, the contact angle with white oil is 0°, the contact angle with water is 153.2°, the saturated adsorption capacity is 38 g / g, and the saturated oil phase adsorption capacity after 30 cycles is 37 g / g.

[0101] The sponge is subjected to the tests of the saturated oil phase adsorption capacity after 30 cycles, the oil phase removal rate and the oil phase selective adsorption rate according to the test requirements, and the results are shown in Table 1.

[0102] Preparation Example 3

[0103] (1) 10 g of an epoxy resin prepolymer solution (Witco) and 0.6 g of hexamethylenetetramine are weighed and dissolved in 200 mL of acetone, and the solution is stirred thoroughly to be clear and transparent.

[0104] (2) A porous melamine-formaldehyde sponge substrate (Beiyou Building Materials) with a size of 200*200*150 mm is used, and the above solution is dispersed into the sponge by spraying and dispersing, so that the curing agent solution uniformly infiltrates the sponge. The sponge after extrusion is placed in a 150°C, 5kPa vacuum oven for curing for 20 min to obtain an oil absorption sponge S3.

[0105] In the oil absorption sponge S3, the mass of the epoxy resin accounts for 3% of the total mass of the sponge. The average pore size of the oil absorption sponge S3 is 250 μm, the porosity is 96%, the open porosity is 98%, the vertical burning level is V-0, the contact angle with white oil is 0°, the contact angle with water is 151.1°, the saturated adsorption capacity is 40 g / g, and the saturated oil phase adsorption capacity after 30 cycles is 35 g / g.

[0106] The sponge is subjected to the tests of the saturated oil phase adsorption capacity after 30 cycles, the oil phase removal rate and the oil phase selective adsorption rate according to the test requirements, and the results are shown in Table 1.

[0107] Preparation Example 4

[0108] According to the method of Preparation Example 3, except that the volume of the porous melamine-formaldehyde sponge substrate is 400*400*150 mm, and the other conditions are the same as those of Preparation Example 3, an oil absorption sponge S4 is obtained.

[0109] In the oil absorption sponge S4, the mass of the epoxy resin accounts for 0.5% of the total mass of the sponge. The average pore size of the oil absorption sponge S4 is 250 μm, the porosity is 92%, the open porosity is 93%, the vertical burning level is V-0, the contact angle with white oil is 0°, the contact angle with water is 146°, the saturated adsorption capacity is 37 g / g, and the saturated oil phase adsorption capacity after 30 cycles is 33 g / g.

[0110] The saturated oil phase adsorption capacity, oil phase removal rate and oil phase selective adsorption rate of the sponge after 30 cycles according to the test requirements were tested, and the results are shown in Table 1.

[0111] Preparation Example 5

[0112] According to the method of Preparation Example 3, except that 20 g of epoxy resin prepolymer solution (Wilsun Guofu) and 1.2 g of hexamethylenetetramine were weighed and dissolved in 200 mL of acetone; the rest of the conditions were the same as those in Preparation Example 3, to obtain oil absorption sponge S5.

[0113] In the oil absorption sponge S5, the mass of epoxy resin accounted for 5% of the total mass of the sponge; the average pore size of the oil absorption sponge S5 was 240 μm, the porosity was 87%, the open porosity was 83%; the vertical combustion grade was V-1; the contact angle with white oil was 0°, and the contact angle with water was 155.4°; the saturated adsorption capacity was 32 g / g; and the saturated oil phase adsorption capacity after 30 cycles was 30 g / g.

[0114] The saturated oil phase adsorption capacity, oil phase removal rate and oil phase selective adsorption rate of the sponge after 30 cycles according to the test requirements were tested, and the results are shown in Table 1.

[0115] Preparation Example 6

[0116] (1) 10 g of phenolic resin prepolymer solution (Meisheng Chemical Plasticization) and 1 g of hexamethylenetetramine were weighed and dissolved in 200 mL of ethanol, and the solution was stirred thoroughly to make it clear and transparent;

[0117] (2) A porous melamine-formaldehyde sponge matrix (Xuexian Industry) with a size of 200*200*150 mm was prepared, and the above-mentioned solution was dispersed into the sponge by extrusion dispersion, so that the curing agent solution uniformly infiltrated the sponge. The sponge after extrusion was placed in a 110°C, 3kPa vacuum oven for curing for 80 min to obtain a sponge containing gelatinous phenolic resin; wherein the gelatinous phenolic resin sponge accounted for 1% of the total mass of the porous melamine-formaldehyde sponge matrix;

[0118] (3) The solution of step (1) was dispersed into the gelatinous phenolic resin-containing sponge obtained in step (2) by extrusion dispersion, so that the solution uniformly infiltrated the sponge. The sponge after extrusion was placed in a 180°C, 3kPa vacuum oven for curing for 20 min to obtain oil absorption sponge S6.

[0119] The phenolic resin accounted for 2% of the total mass of the oil absorption sponge S6; the average pore size of the oil absorption sponge was 100 μm, the porosity was 95%, the open porosity was 98%, the vertical combustion grade was V-0, the contact angle with white oil was 0°, and the contact angle with water was 153.8°; the saturated oil phase adsorption capacity was 44 g / g; and the saturated oil phase adsorption capacity after 30 cycles was 43 g / g.

[0120] Preparation Example 7

[0121] (1) Take 10 g of phenolic resin prepolymer solution (Meisheng Chemical Industry) and 1 g of hexamethylenetetramine dissolved in 200 mL of ethanol, and stir well to make the solution clear and transparent;

[0122] (2) Measure 200*200*150 mm of porous melamine-formaldehyde sponge matrix (Xuexian Industry), and disperse the above solution into the sponge by extrusion dispersion, so that the curing agent solution uniformly infiltrates the sponge. Place the extruded sponge in a 110°C, 3kPa vacuum oven for 80 min to cure, to obtain a sponge containing gelatinous phenolic resin. Then place the pre-cured sponge in a 180°C, 3kPa vacuum oven for 20 min to cure, to obtain oil-absorbing sponge S7.

[0123] In the oil-absorbing sponge S7, the mass of phenolic resin accounts for 2% of the total mass of the oil-absorbing sponge; the average pore size of the oil-absorbing sponge S8 is 100 μm, the porosity is 95%, the open porosity is 98%, the vertical burning grade is V-0, the contact angle with white oil is 0°, and the contact angle with water is 152.7°; the saturated oil phase adsorption capacity is 41 g / g; after 30 cycles, the saturated oil phase adsorption capacity is 40 g / g.

[0124] Preparation Example 8

[0125] According to the method of Preparation Example 1, except that the impregnation amount of phenolic resin prepolymer is adjusted so that the mass of phenolic resin accounts for 7% of the total mass of the oil-absorbing sponge, and the other conditions are the same as those of Preparation Example 1, to obtain oil-absorbing sponge D1.

[0126] In the oil-absorbing sponge D1, the mass of phenolic resin accounts for 7% of the total mass of the sponge; the average pore size of the oil-absorbing sponge D1 is 230 μm, the porosity is 73%, and the open porosity is 69%; the vertical burning grade is V-2; the contact angle with white oil is 0°, and the contact angle with water is 158.1°; the saturated adsorption capacity is 27 g / g; after 30 cycles, the saturated oil phase adsorption capacity is 20 g / g.

[0127] Figure 5 The SEM photo of sponge D1, compared to the oil-absorbing sponge S1 ( Figure 2 ), the skeleton and skeleton junction of the sponge are obviously covered with more phenolic resin, so that the porosity of the sponge decreases, and the corresponding saturated adsorption capacity also decreases. Moreover, the distribution of phenolic resin on the surface of the skeleton is uneven, and stress concentration easily occurs during the recycling process, leading to the collapse of the skeleton. Figure 6 The photo of the skeleton of sponge D1 after 30 cycles of recycling, the bulk density of the skeleton obviously increases, leading to a decrease in the saturated adsorption capacity.

[0128] The saturated oil phase adsorption capacity, oil phase removal rate, and oil phase selective adsorption rate of the sponge after 30 cycles of recycling were tested according to the test requirements, and the results are shown in Table 1.

[0129] Preparation Example 9

[0130] According to the method of Preparation Example 1, except that in step (2), the curing was carried out at normal pressure, specifically, the extruded sponge was placed in an oven at 180°C for 20 min, and the other conditions were the same as in Preparation Example 1, to obtain oil-absorbing sponge D2.

[0131] In oil-absorbing sponge D2, the mass of phenolic resin accounted for 0.2% of the total mass of the sponge; the average pore size of oil-absorbing sponge D2 was 250 μm, the porosity was 96%, and the open porosity was 98%; the vertical burning rating was V-0; the contact angle with white oil was 0°, and the contact angle with water was 133.1°; the saturated adsorption capacity was 30 g / g; and the saturated oil phase adsorption capacity after 30 cycles was 20 g / g.

[0132] The saturated oil phase adsorption capacity, oil phase removal rate, and oil phase selective adsorption rate of the sponge after 30 cycles were tested according to the test requirements, and the results are shown in Table 1.

[0133] Examples 1-7 and Comparative Examples 1-2

[0134] The oil-absorbing sponges prepared in Preparation Examples 1-7 and Preparation Examples 8-9 were respectively filled above the tray 2 to a height of 1 / 2 of the height of the tank above the tray 2, and then purging gas adsorption was carried out, with the adsorption method as follows:

[0135] The purging gas was input into the collection chamber through the purging gas inlet pipeline 4, and the purging gas contacted the oil-absorbing sponge 3 in the purging gas adsorption chamber through the tray 2, and the condensable gas in the purging gas condensed into droplets, which dropped into the collection chamber under the action of gravity;

[0136] The remaining purging gas was discharged through the purging gas outlet pipeline 5;

[0137] The adsorption temperature was 35°C, and the adsorption pressure was normal pressure;

[0138] The composition of the purging gas was 85 vol% nitrogen, 10 vol% p-xylene, and 5 vol% toluene.

[0139] Comparative Example 3

[0140] According to the method of Example 3, the filled oil-absorbing sponge was unmodified porous melamine-formaldehyde sponge matrix (Beiyujiancai) D3, and the other conditions were the same as in Example 3.

[0141] Table 1

[0142]

[0143] The preferred embodiments of the present application are described in detail above, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including that each technical feature is combined in any other suitable manner. These simple modifications and combinations should also be considered as disclosed by the present application and fall within the protection scope of the present application.

Claims

1. A closed-sampling purge gas adsorption canister, characterized by, The adsorption tank comprises: a tank body (1) and a containing cavity formed by surrounding the tank body (1); a supporting plate (2) sealingly arranged in the containing cavity, a liquid collecting cavity being formed below the supporting plate (2) and the tank body (1), and a purge gas adsorption cavity being formed above the supporting plate (2) and the tank body (1); the supporting plate (2) is provided with a gas flow channel; a sponge (3) arranged on the supporting plate (2) and used for contacting with the purge gas to condense the condensable gas in the purge gas into liquid droplets; a purge gas inlet pipeline (4) and a purge gas outlet pipeline (5) penetrating through the tank body (1), a port of the purge gas inlet pipeline (4) being arranged below the supporting plate (2), and a port of the purge gas outlet pipeline (5) being arranged above the sponge (3); the sponge (3) comprises an oil-absorbing sponge, the oil-absorbing sponge comprises a three-dimensional porous polymer matrix and a thermosetting resin coated on the three-dimensional porous polymer matrix; the oil-absorbing sponge has an adsorption capacity for oil products of not less than 30 g / g; the oil-absorbing sponge has a saturated adsorption capacity for oil products of not less than 30 g / g after 30 times of adsorption-desorption cycles; the mass of the thermosetting resin accounts for 0.5-5% of the total mass of the sponge; the oil-absorbing sponge has a pore size of 10-500 μm and a porosity of not less than 60%; the preparation method of the oil-absorbing sponge comprises: dispersing a solution containing a thermosetting resin prepolymer and a curing agent into the three-dimensional porous polymer matrix, and curing under vacuum to obtain the oil-absorbing sponge; the vacuum condition comprises: a pressure of 0-10 kPa.

2. The adsorption canister of claim 1, wherein, the tank body (1) is further provided with a liquid discharge valve (6) arranged at the bottom of the tank body (1) and used for discharging the collected liquid droplets; and / or the supporting plate (2) is provided with an opening, and the opening has a pore size of 5-20 mm.

3. The adsorption can according to claim 1 or 2, wherein, the mass of the thermosetting resin accounts for 2-3% of the total mass of the sponge; and / or the oil-absorbing sponge has a saturated adsorption capacity for oil products of 30-50 g / g, and the oil-absorbing sponge has a saturated adsorption capacity for oil products of 30-50 g / g after 30 times of desorption-adsorption cycles.

4. The adsorption can according to claim 1 or 2, wherein, the thermosetting resin is selected from at least one of a phenolic resin, an epoxy resin, a urea-formaldehyde resin, an unsaturated polyester resin and an organic silicon resin; and / or the three-dimensional porous polymer matrix is selected from at least one of a melamine-formaldehyde sponge, a polyurethane sponge and an ethylene-vinyl acetate sponge.

5. The adsorption can according to claim 1 or 2, wherein, the thermosetting resin is selected from at least one of a phenolic resin, an epoxy resin and an organic silicon resin; and / or the three-dimensional porous polymer matrix is a melamine-formaldehyde sponge.

6. The adsorption tank according to claim 1 or 2, wherein the static planar contact angle of the oil-absorbing sponge surface to water in air is greater than 135°; and / or the static contact angle of the oil-absorbing sponge surface to white oil is less than 30°; and / or the UL94 vertical burning test grade of the oil-absorbing sponge is above V-2 grade.

7. The adsorption canister of claim 1 or 2, wherein, the curing condition comprises: a temperature of 80-200 ℃ and a curing time of 5-120 min.

8. The adsorption canister of claim 1 or 2, wherein, the preparation method of the oil-absorbing sponge comprises: (1) dispersing a solution containing a thermosetting resin prepolymer and a curing agent into the three-dimensional porous polymer matrix, and pre-curing under a first vacuum condition; (2) dispersing a solution containing a thermosetting resin prepolymer and a curing agent into the product obtained in step (1), and curing under a second vacuum condition; The first vacuum condition and the second vacuum condition each include a pressure of 0-10 kPa; The pre-curing condition includes a temperature of 80-120°C; The curing condition includes a temperature of 140-180°C.

9. A closed- cycle purge and trap gas adsorption method, characterized by, The method is performed in the adsorption canister described in any one of claims 1-8, and the method includes: The purge gas is input into the collecting chamber through the purge gas inlet pipeline (4), and the purge gas contacts the sponge (3) in the purge gas adsorption chamber through the supporting plate (2), the condensable gas in the purge gas condenses into liquid droplets, and the liquid droplets drop into the collecting chamber under the action of gravity; The remaining purge gas is discharged through the purge gas outlet pipeline (5).

10. The adsorption method according to claim 9, wherein, The purge gas is from a PX device, and the purge gas contains toluene at 0-10% by volume fraction, p-xylene at 0-20% by volume fraction, and nitrogen at 70-98% by volume fraction; And / or The adsorption condition includes a temperature of -20-40°C; And / or The liquid droplets collected in the collecting chamber are discharged through the liquid discharge valve (7).

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