CN108101066B - Preparation method and application of hydrophobic spherical ordered hierarchical porous silicon dioxide adsorbent - Google Patents
Preparation method and application of hydrophobic spherical ordered hierarchical porous silicon dioxide adsorbent Download PDFInfo
- Publication number
- CN108101066B CN108101066B CN201711183396.8A CN201711183396A CN108101066B CN 108101066 B CN108101066 B CN 108101066B CN 201711183396 A CN201711183396 A CN 201711183396A CN 108101066 B CN108101066 B CN 108101066B
- Authority
- CN
- China
- Prior art keywords
- preparation
- hierarchical porous
- adsorbent
- toluene
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
- B01J20/10—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate
- B01J20/103—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate comprising silica
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/22—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising organic material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
- B01J20/28057—Surface area, e.g. B.E.T specific surface area
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
- B01J20/28057—Surface area, e.g. B.E.T specific surface area
- B01J20/28064—Surface area, e.g. B.E.T specific surface area being in the range 500-1000 m2/g
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
- B01J20/28069—Pore volume, e.g. total pore volume, mesopore volume, micropore volume
- B01J20/28073—Pore volume, e.g. total pore volume, mesopore volume, micropore volume being in the range 0.5-1.0 ml/g
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
- B01J20/28078—Pore diameter
- B01J20/28083—Pore diameter being in the range 2-50 nm, i.e. mesopores
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/04—Particle morphology depicted by an image obtained by TEM, STEM, STM or AFM
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/14—Pore volume
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/16—Pore diameter
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/19—Oil-absorption capacity, e.g. DBP values
Abstract
The invention discloses a hydrophobic spherical ordered hierarchical porous silicon dioxide adsorbent and a preparation method and application thereof, wherein the preparation method comprises the following steps: (1) preparing spherical ordered hierarchical porous silicon dioxide; (2) dispersing the spherical ordered hierarchical porous silica in toluene, adding an organosilane coupling agent, after hydrothermal reaction, fully washing a reaction product with toluene and absolute ethyl alcohol, and drying in vacuum to obtain the silica-based composite material; the organosilane coupling agent is one or two of bromomethyltrimethylsilane, iodomethyltrimethylsilane, trifluoromethyltrimethylsilane and trimethylchlorosilane. The adsorbent prepared by the invention has the advantages of strong hydrophobic property, large adsorption capacity, adjustable aperture, simple adsorption and desorption, and good adsorption and enrichment effects on organic waste gas with large air volume and low concentration.
Description
Technical Field
The invention belongs to the field of environmental functional materials, and particularly relates to a preparation method and a specific application of a hydrophobic spherical ordered hierarchical porous silicon dioxide adsorbent material.
Background
With the rapid development of economy and industry in China, the material requirements of people are met, meanwhile, the quality of the ecological environment is emphasized, and the environmental pollution becomes a serious problem to be solved urgently. Volatile organic pollutants (VOCs) refer to compounds with a boiling point lower than 260 ℃ at normal temperature, and are main pollutants in the industries of petrochemical industry, printing, coating, shoe manufacturing, automobile spraying and the like, automobile exhaust emission and the like. Part of VOCs are flammable and explosive, and have great threat to production, transportation safety and the like; part of VOCs can damage nerve and mucosa tissues of a human body and has the function of 'three causes'; VOCs can also generate photochemical reaction with nitrogen oxides under the illumination condition to generate photochemical smog, and great harm is generated to the environment.
At present, the relatively mature treatment method for the volatile organic waste gas abroad is the combination of rotary wheel adsorption concentration and regenerative catalytic combustion. The common adsorbents mainly comprise activated carbon and microporous molecular sieves, and although the activated carbon has large adsorption capacity, the activated carbon has the main defects of potential safety hazard due to flammability and difficult desorption; the pore size of the microporous molecular sieve is small, the microporous molecular sieve has weak diffusion and adsorption capacity on macromolecular VOCs and is difficult to desorb, carbon deposition is easily generated to block pore channels, the adsorption capacity of the microporous molecular sieve is reduced, and the treatment effect of organic waste gas is influenced. Considering that the hierarchical pore molecular sieve has micropores and mesopores, the hierarchical pore molecular sieve not only can effectively reduce diffusion resistance, but also has good hydrothermal stability and high specific surface area, and has huge application prospect.
Currently, methods for synthesizing a hierarchical pore molecular sieve include a post-treatment method and a template synthesis method. The post-treatment method is to remove part of silicon and aluminum elements in the framework of the microporous molecular sieve by acid and alkali treatment so as to introduce mesopores, wherein the pore size of the introduced mesopores is not controllable, and the structure of part of the molecular sieve is damaged so as to reduce the performance of the molecular sieve. The hierarchical pore molecular sieve synthesized by adopting a template method can ensure the orderliness of the structure, and the national published patent No. CN106861614A provides a preparation method of a hierarchical pore 5A molecular sieve adsorbent, polyquaternary ammonium salt is used as a template agent and added into a sol system mixed by a silicon source and an aluminum source, a hierarchical pore 4A molecular sieve with a micropore-mesopore structure is hydrothermally synthesized, and then the 4A molecular sieve is subjected to calcium ion exchange and activation to obtain the 5A molecular sieve adsorbent with the micropore-mesopore structure, so that the 5A molecular sieve adsorbent has higher equilibrium adsorption quantity on normal paraffin, the diffusion coefficient of the normal paraffin in the molecular sieve is obviously improved, and the adsorption separation rate is improved. The published patent number of China CN103949204A provides a preparation method for synthesizing a multi-stage pore canal composite molecular sieve adsorbent, which needs to synthesize a ten-element microporous molecular sieve first and then hydrothermally synthesize a mesoporous molecular sieve, wherein the pore diameter of the composite molecular sieve is less than or equal to 2.83nm, the specific surface area is small, the preparation method is complex, and the composite molecular sieve is not suitable for adsorption of industrial organic waste gas. Therefore, it is necessary to research a hierarchical pore molecular sieve which has a large specific surface area, an adjustable pore diameter, and simple and convenient synthesis conditions and is suitable for industrial application.
Researchers find that when the template method is used for synthesizing the silicon dioxide, a large amount of silicon hydroxyl (Si-OH) can be formed on the surface after the template agent is removed by firing or solvent extraction, the silicon dioxide has strong affinity to water, and when VOCs are adsorbed, water molecules and VOCs molecules form competitive adsorption on the surface of the adsorbent, so that the adsorption and purification effects of the VOCs are influenced. Dou et al [ Dou B, HuQ, LiJ, et al.Admission Performance of VOCs in ordered mesoporous silicas with differential pore structures and surface chemistry [ J ]. Journal of hazardous materials,2011,186 (2-3): 1615-. The research on the silanization and hydrophobic modification of a ZSM-5 high-silica molecular sieve [ J ] chemical research and application, 2013,25(2):236-239 ] of the Lichenlong and the like adopts n-octyl triethoxysilane to carry out surface silane modification on the ZSM-5 molecular sieve with the high silica-alumina ratio, and the experimental result shows that the adsorption capacity of the modified molecular sieve to water is reduced by 1.46%, but the specific surface area and the pore volume are both obviously reduced. Therefore, the adoption of the long carbon chain modifier can cause the reduction of the pore volume of the adsorbent, and even block the pore channel when the pore volume is serious, so that the adsorption performance of the adsorbent is reduced.
Disclosure of Invention
The invention aims to overcome the defects of the existing adsorbent and provide a preparation method and application of a hierarchical pore silica adsorbent which is strong in hydrophobic property, large in adsorption capacity, adjustable in pore diameter and simple in adsorption and desorption.
A preparation method of a hydrophobic spherical ordered hierarchical porous silica adsorbent comprises the following steps:
(1) dissolving P123 (polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer) in hydrochloric acid, fully dissolving CTAB (cetyl trimethyl ammonium bromide) and TMB (1,3, 5-trimethylbenzene) in deionized water, uniformly mixing the two solutions, then dropwise adding tetraethyl silicate, violently stirring to fully hydrolyze the template agent and the tetraethyl silicate, transferring the mixture into a polytetrafluoroethylene hydrothermal kettle after stirring is finished for two-step hydrothermal treatment, washing solid particles to be neutral by using deionized water, drying, and roasting at 500-600 ℃ to obtain spherical ordered hierarchical porous silicon dioxide;
(2) dispersing the spherical ordered hierarchical porous silica in toluene, adding an organosilane coupling agent, after hydrothermal reaction, fully washing a reaction product with toluene and absolute ethyl alcohol, and drying in vacuum to obtain the silica-based composite material; the organosilane coupling agent is one or two of bromomethyltrimethylsilane (TMBS), iodomethyltrimethylsilane (TMIS), trifluoromethyltrimethylsilane (TFMTMS) and Trimethylchlorosilane (TMCS).
The spherical mesoporous silica has the advantages of high hydrothermal stability, large specific surface area, large pore volume and uniform and ordered pore channel structure, and is widely applied to the fields of chromatographic substrates, catalyst carriers, drug diffusion, electrode materials, adsorption and the like. Compared with the traditional microporous molecular sieve adsorbent, the spherical ordered hierarchical porous silica adsorbent has the advantages of large adsorption capacity, low diffusion resistance, simple desorption and the like. Therefore, the invention adopts bromomethyltrimethylsilane, iodomethyltrimethylsilane, trifluoromethyltrimethylsilane and trimethylchlorosilane with short carbon chains to modify the synthesized ordered hierarchical porous silica, improves the pore structure and the surface hydrophobic property of the silica adsorbent, develops a high-efficiency adsorbent with good hydrophobic property, stable structure, large adsorption capacity and small diffusion resistance, and is used for treating organic waste gas with low concentration and large air volume in industry.
The invention adopts a hydrothermal method to synthesize ordered hierarchical porous silica, and then uses a solvothermal method to carry out hydrophobic modification on the silica, so as to prepare the adsorbent for adsorbing and enriching industrial organic waste gas with large air volume and low concentration, namely the hydrophobic spherical ordered hierarchical porous silica adsorbent.
According to the invention, bromomethyltrimethylsilane (TMBS), iodomethyltrimethylsilane (TMIS), trifluoromethyltrimethylsilane (TFMTMS) and Trimethylchlorosilane (TMCS) are grafted on the surface of the hydrophobic spherical ordered hierarchical porous silica adsorbent, the hydrophobicity can be comparable with that of the adsorbent modified by adopting a long carbon chain silane coupling agent, but the influence of the change of the pore volume and the specific surface area is less than that of the adsorbent introduced with the long carbon chain modifying agent. The specific surface area of the finished product spherical ordered hierarchical pore silicon dioxide adsorbent prepared by the method is 500-1000 m2The pore diameter is 0.1-100 nm, and the pore volume is 0.4-1.5 cm3/g。
Preferably, the molar ratio of the tetraethyl silicate to the P123 in the step (1) is 20-200; the molar ratio of P123 to CTAB is 0.001-1; the mass ratio of P123 to TMB is 0.01-50.
Further preferably, the molar ratio of the tetraethyl silicate to the P123 in the step (1) is 50-150; the molar ratio of P123 to CTAB is 0.2-0.7; the mass ratio of P123 to TMB is 0.5 to 10, and more preferably the mass ratio of P123 to TMB is 0.5 to 2.
Most preferably, the molar ratio of tetraethyl silicate to P123 in step (1) is 90; the molar ratio of P123 to CTAB was 0.36; the mass ratio of P123 to TMB was 0.5.
Preferably, the concentration of the hydrochloric acid in the step (1) is 1-12 mol/L, and the molar ratio of the hydrochloric acid to the tetraethyl silicate is 1-10. Further preferably, the concentration of the hydrochloric acid is 2mol/L, and the molar ratio of the hydrochloric acid to the tetraethyl silicate is 2-5; most preferably 3.
Preferably, the hydrolysis stirring temperature in the step (1) is 35-60 ℃, and the stirring time is 0.5-48 h; the temperature of the two-step hydrothermal treatment is 35-200 ℃, and the reaction time is 0-48 h.
Further preferably, the hydrolysis stirring temperature in the step (1) is 35-40 ℃, and the stirring time is 10-25 h; the temperature of the first stage hydrothermal treatment is 60-100 ℃, the reaction time is 20-25 h, the temperature of the second stage hydrothermal treatment is 80-150 ℃, and the reaction time is 6-24 h.
Further preferably, the hydrolysis stirring temperature in the step (1) is 35-36 ℃, and the stirring time is 15-25 h; the temperature of the first stage hydrothermal treatment is 60-80 ℃, the reaction time is 24-25 h, the temperature of the second stage hydrothermal treatment is 100-130 ℃, and the reaction time is 6-15 h.
Most preferably, the hydrolysis stirring temperature in the step (1) is 35 ℃, and the stirring time is 20 h; the temperature of the first stage hydrothermal treatment is 70 ℃, the reaction time is 24 hours, the temperature of the second stage hydrothermal treatment is 120 ℃, and the reaction time is 12 hours.
The two-step hydrothermal method comprises the steps of carrying out hydrothermal treatment at a low temperature, so that the larger specific surface area and pore volume of micropores of a sample can be ensured, carrying out hydrothermal treatment at a higher temperature in the second stage, ensuring the effect of a pore-expanding agent TMB, further expanding the pore diameter of the hierarchical pore molecular sieve while keeping the micropore structure, and promoting the structure of the synthesized hierarchical pore molecular sieve to be more stable and ordered.
The stirring speed of the violent stirring is 200-500 rpm.
Preferably, the roasting time in the step (1) is 1-20 h, and the temperature rise rate is 1-20 ℃/min.
Further preferably, in the step (1), the roasting temperature is 550 ℃, the roasting time is 3-6 h, and the temperature rise rate is 1-3 ℃/min.
Most preferably, the roasting temperature in the step (1) is 550 ℃, the roasting time is 5h, and the temperature rising rate is 3 ℃/min.
Preferably, the concentration of the spherical ordered multi-hole silica in the toluene in the step (2) is 5-20 g/L.
Preferably, the hydrothermal reaction temperature in the step (2) is 70-200 ℃, and the reaction time is 2-36 h. Further preferably, the hydrothermal reaction temperature in the step (2) is 80-120 ℃, and the reaction time is 20-25 h. Most preferably, the hydrothermal reaction temperature in step (2) is 100 ℃ and the reaction time is 24 h.
Preferably, the washing time of the toluene and the absolute ethyl alcohol in the step (2) is 1-5 h; the temperature of vacuum drying is 70-150 ℃, and the time is 6-24 h.
Further preferably, the vacuum drying temperature is 100 ℃ and the drying time is 12 h.
The invention also provides the hydrophobic spherical ordered hierarchical porous silica adsorbent prepared by the preparation method. The adsorbent is applied to the adsorption and concentration of industrial organic waste gas with large air volume and low concentration.
The application method comprises the following steps:
loading a proper amount of adsorbent on a honeycomb ceramic carrier, enabling industrial organic waste gas to pass through the adsorbent, adsorbing organic matters, purifying gas, driving the adsorbent saturated in adsorption to rotate to a regeneration area under the drive of a motor, regenerating the adsorbent by high-temperature desorption, cooling the regenerated adsorbent, then rotating to the adsorption area for adsorption again, and periodically adsorbing, desorbing and cooling the adsorbent along with the rotation of a rotating wheel to realize the purification of the organic waste gas.
Compared with the prior art, the invention has the following advantages:
(1) the aperture of the hierarchical porous silica synthesized by the method can be regulated and controlled by changing the proportion of adding the silane coupling agent and adding the TMB, and the aperture can be changed within 2-50 nm. The synthesis method is simple, the reaction condition is mild, and the method is suitable for industrial production.
(2) Compared with the common microporous adsorbent, the hierarchical porous silica synthesized by the invention has the advantages of large adsorption capacity, small diffusion resistance, simple desorption and the like, can still maintain higher adsorption capacity after multiple adsorption and desorption cycles, and is not easy to deposit carbon.
(3) According to the hydrophobic hierarchical porous silica prepared by the invention, bromomethyltrimethylsilane (TMBS), iodomethyltrimethylsilane (TMIS), trifluoromethyltrimethylsilane (TFMTMS) and Trimethylchlorosilane (TMCS) are used as modifiers, the carbon chain grafted to the surface of the adsorbent is shorter, the influence on the pore structure of the adsorbent is smaller, and higher hydrophobicity can be still maintained on the basis of maintaining the adsorption performance of the hierarchical porous silica.
Drawings
Figure 1 is a small angle XRD pattern of the synthetic product of example 3.
FIG. 2 is a low temperature nitrogen adsorption-desorption isotherm diagram of the synthetic product of example 3.
FIG. 3 is a graph of pore volume as a function of pore diameter obtained by BJH desorption of the synthetic product of example 3.
FIG. 4 is a graph showing the adsorption breakthrough of the synthetic product TMCS-sphere SBA-15.
FIG. 5 shows adsorption and desorption cycle performance data of the synthesized TMCS-spherial SBA-15 product.
FIG. 6 is a scanning electron micrograph of the resultant product.
FIG. 7 is a transmission electron micrograph of the resultant product.
Detailed Description
The present invention will be further described in detail with reference to the following examples:
example 1: preparation of TMBS-spherial SBA-15 adsorbent:
controlling the molar ratio of tetraethyl silicate to P123 to be 90, dissolving P123 in 90ml of 2mol/L hydrochloric acid solution, controlling the mass ratio of P123 to TMB to be 0.5 and the molar ratio of P123 to CTAB to be 0.25, dissolving TMB and CTAB in 30ml of deionized water, mixing and stirring the two mixed solutions at 35 ℃, and dropwise adding tetraethyl silicate. Stirring for 20h, transferring the mixture into a stainless steel hydrothermal kettle with a polytetrafluoroethylene lining, carrying out hydrothermal reaction at 70 ℃ for 24h, carrying out hydrothermal reaction at 120 ℃ for 12h, cleaning the precipitate to neutrality, drying, and roasting at 550 ℃ for 5h for later use. 1g of the calcined sphenicalSBA-15 was added with 100ml of toluene and 0.2mmol of TMBS, and subjected to hydrothermal reaction at 100 ℃ for 24 hours. And after the reaction is finished, carrying out suction filtration on the suspension, washing the obtained solid particles for 3h by using toluene and absolute ethyl alcohol, and drying at 100 ℃ for 12h to obtain the bromomethyl trimethyl silane modified molecular sieve which is recorded as TMBS-sphere SBA-15.
The TMBS-spherial SBA-15 adsorbent has the specific surface area tested to be 761.2m2Per g, pore volume 0.65cm3The BJH adsorption pore diameter is 8.9nm, and the toluene dynamic saturation adsorption capacity reaches 99.3mg/g at 30 ℃.
Example 2: preparation of TFMTMS-spherial SBA-15 adsorbent:
controlling the molar ratio of tetraethyl silicate to P123 to be 90, dissolving P123 in 90ml of 2mol/L hydrochloric acid solution, controlling the mass ratio of P123 to TMB to be 0.5 and the molar ratio of P123 to CTAB to be 0.5, dissolving TMB and CTAB in 30ml of deionized water, mixing and stirring the two mixed solutions at 35 ℃, and dropwise adding tetraethyl silicate. Stirring for 20h, transferring the mixture into a stainless steel hydrothermal kettle with a polytetrafluoroethylene lining, carrying out hydrothermal reaction at 70 ℃ for 24h, carrying out hydrothermal reaction at 120 ℃ for 12h, cleaning the precipitate to neutrality, drying, and roasting at 550 ℃ for 5h for later use. 1g of the calcined sphenicalSBA-15 was added with 100ml of toluene and 0.2mmol of TFMTMS, and subjected to hydrothermal reaction at 100 ℃ for 24 hours. And after the reaction is finished, carrying out suction filtration on the suspension, washing the obtained solid particles for 3h by using toluene and absolute ethyl alcohol, and obtaining the trifluoromethyl trimethylsilane modified molecular sieve which is marked as TFMTMS-sphere SBA-15.
The TFMTMS-polymeric SBA-15 adsorbent has a specific surface area of 825.6m2Per g, pore volume 0.87cm3The BJH adsorption pore diameter is 11.8nm, and the toluene dynamic saturation adsorption capacity reaches 103.9mg/g at 30 ℃.
Example 3: preparation of TMCS-spherial SBA-15 adsorbent:
controlling the molar ratio of tetraethyl silicate to P123 to be 90, dissolving P123 in 90ml of 2mol/L hydrochloric acid solution, controlling the mass ratio of P123 to TMB to be 0.5 and the molar ratio of P123 to CTAB to be 0.36, dissolving TMB and CTAB in 30ml of deionized water, mixing and stirring the two mixed solutions at 35 ℃, and dropwise adding tetraethyl silicate. Stirring for 20h, transferring the mixture into a stainless steel hydrothermal kettle with a polytetrafluoroethylene lining, carrying out hydrothermal reaction at 70 ℃ for 24h, carrying out hydrothermal reaction at 120 ℃ for 12h, cleaning the precipitate to neutrality, drying, and roasting at 550 ℃ for 5h for later use. 1g of the calcined sphenica SBA-15 was added with 100ml of toluene and 0.2mmol of TMCS, and subjected to hydrothermal reaction at 100 ℃ for 24 hours. And after the reaction is finished, carrying out suction filtration on the suspension, and washing the obtained solid particles for 3 hours by using toluene and absolute ethyl alcohol to obtain the trimethylchlorosilane modified molecular sieve which is marked as TMCS-molecular SBA-15.
The TMCS-spherial SBA-15 adsorbent was tested to have a specific surface area of 738.8m2Per g, pore volume 0.88cm3The BJH adsorption pore diameter is 10.2nm, and the toluene dynamic saturation adsorption capacity reaches 105.0mg/g at 30 ℃.
Example 4: preparation of TMIS-sphericalSBA-15 adsorbent
Controlling the molar ratio of tetraethyl silicate to P123 to be 150, dissolving P123 in 90ml of 2mol/L hydrochloric acid solution, controlling the mass ratio of P123 to TMIS to be 1, dissolving TMB and CTAB in 30ml of deionized water, mixing and stirring the two mixed solutions at 35 ℃, and dropwise adding tetraethyl silicate. Stirring for 20h, transferring the mixture into a stainless steel hydrothermal kettle with a polytetrafluoroethylene lining, performing hydrothermal treatment at 70 ℃ for 24h and at 120 ℃ for 12h, cleaning the precipitate to be neutral, drying, and roasting at 550 ℃ for 5h for later use. 1g of the calcined sphenicalSBA-15 was added with 100ml of toluene and 0.2mmol of TMIS, and subjected to hydrothermal reaction at 100 ℃ for 24 hours. And after the reaction is finished, carrying out suction filtration on the suspension, washing the obtained solid particles for 3h by using toluene and absolute ethyl alcohol, and obtaining the iodomethyl trimethyl silane modified molecular sieve which is recorded as TMIS-molecular SBA-15.
The TMIS-sphericalSBA-15 adsorbent is tested to have the specific surface area of 752.6m2Per g, pore volume 0.65cm3The BJH adsorption pore diameter is 9.1nm, and the toluene dynamic saturation adsorption capacity reaches 103.9mg/g at 30 ℃.
Example 5: structural characterization of the synthetic products of the invention
The present example is a structural characterization of the TMCS-polymeric sba-15 adsorbent obtained in example 3, and mainly includes the following aspects;
x-ray powder diffraction was used to analyze the pore structures of unmodified spherulasA-15 and TMCS-spherulasA-15, and the results are shown in FIG. 1. As can be seen from the figure, TMCS-polymeric SBA-15 retains the mesoporous structure and long-range order of unmodified polymeric SBA-15.
The adsorbent specific surface area and pore size distribution were measured using a profilometer and the results are shown in fig. 2 and 3. As can be seen from the isothermal adsorption curve, the specific surface area of the modified sample micropores is not substantially changed, and the specific surface areas of the unmodified polymeric SBA-15 and the TMCS-polymeric SBA-15 are 871.4m2G and 738.8m2The pore volume is 0.94 cm/g3G and 0.88cm3The pore diameters are respectively 10.8nm and 10.2nm, and the visible specific surface area and the pore volume are reserved.
Example 6: adsorption Performance testing of the synthetic products of the invention
Toluene (500ppm, 50ml/min) was selected as the target contaminant and a mini fixed bed reactor was used for the adsorption experiments. Taking 0.1g TMCS-polymeric SBA-15 adsorbent, respectively carrying out dynamic adsorption experiments at 30 ℃ and relative humidity of 0% and 50%, and detecting the concentration of toluene in inlet and outlet gases by gas chromatography.
As a control, adsorption experiments were performed under the same conditions using unmodified sphenicalSBA-15.
As can be seen from FIG. 4, the modified TMCS-spherulaSBA-15 adsorbent still can maintain a good adsorption capacity at a relative humidity of 50%, the saturated adsorption capacity is 80.1mg/g, and the unmodified spherulaSBA-15 adsorbent has a significant reduction of the saturated adsorption capacity of only 32.9mg/g at a relative humidity of 50%.
Example 7: absorption and desorption cycle performance test of the synthetic product
The adsorption and desorption cycle test is carried out on a micro fixed bed, TMCS-molecular SBA-15 which is saturated by adsorption under the relative humidity of 0% in the embodiment 6 is blown by nitrogen at 150 ℃ until no toluene exists in tail gas, the dynamic adsorption experiment is carried out again after the temperature is cooled to 30 ℃, the desorption cycle performance of the synthesized product is shown in figure 5, and it can be seen that when the adsorption and desorption cycle is carried out to the 10 th time, the toluene dynamic saturation adsorption capacity of a sample under the temperature of 30 ℃ can still be kept at 103.0mg/g, the loss capacity is only 1.9%, and the synthesized sample is proved to have excellent adsorption and desorption performance, good regeneration capacity at a lower temperature (150 ℃) and huge industrial application potential.
The above description is only an embodiment of the present invention, but the technical features of the present invention are not limited thereto, and any person skilled in the relevant art can change or modify the present invention within the scope of the present invention.
Claims (10)
1. A preparation method of a hydrophobic spherical ordered hierarchical porous silica adsorbent is characterized by comprising the following steps:
(1) dissolving a polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer in hydrochloric acid, fully dissolving hexadecyl trimethyl ammonium bromide and 1,3, 5-trimethylbenzene in deionized water, uniformly mixing the two solutions, dropwise adding tetraethyl silicate, violently stirring to fully hydrolyze the template agent and the tetraethyl silicate, transferring the mixture into a polytetrafluoroethylene hydrothermal kettle after stirring is finished, carrying out two-step hydrothermal treatment, washing solid particles to be neutral by using deionized water, drying, and roasting at 500-600 ℃ to obtain spherical ordered hierarchical porous silicon dioxide; in the two-step hydrothermal treatment process: the temperature of the first stage hydrothermal treatment is 60-100 ℃, the reaction time is 20-25 h, the temperature of the second stage hydrothermal treatment is 80-150 ℃, and the reaction time is 6-24 h;
(2) dispersing the spherical ordered hierarchical porous silica in toluene, adding an organosilane coupling agent, after hydrothermal reaction, fully washing a reaction product by using toluene and absolute ethyl alcohol, and drying in vacuum to obtain the silica-based composite material; the organosilane coupling agent is one or two of bromomethyltrimethylsilane, iodomethyltrimethylsilane, trifluoromethyltrimethylsilane and trimethylchlorosilane.
2. The preparation method according to claim 1, wherein the molar ratio of tetraethyl silicate to P123 in step (1) is 20-200; the molar ratio of P123 to CTAB is 0.001-1; the mass ratio of P123 to TMB is 0.01-50.
3. The method according to claim 1, wherein the concentration of hydrochloric acid in step (1) is 1 to 12mol/L, and the molar ratio of hydrochloric acid to tetraethyl silicate is 1 to 10.
4. The preparation method according to claim 1, wherein the hydrolysis stirring temperature in the step (1) is 35-60 ℃, and the stirring time is 10-48 h.
5. The preparation method according to claim 1, wherein the calcination time in the step (1) is 1-20 h, and the temperature rise rate is 1-20 ℃/min.
6. The preparation method according to claim 1, wherein the concentration of the spherical ordered hierarchical porous silica in toluene in the step (2) is 5-20 g/L.
7. The preparation method according to claim 1, wherein the hydrothermal reaction temperature in the step (2) is 70-200 ℃ and the reaction time is 2-36 hours.
8. The preparation method according to claim 1, wherein the washing time of the toluene and the absolute ethyl alcohol in the step (2) is 1-5 h; the temperature of vacuum drying is 70-150 ℃, and the time is 6-24 h.
9. The hydrophobic spherical ordered hierarchical porous silica adsorbent prepared by the preparation method of any one of claims 1 to 8.
10. Use of the hydrophobic spherical ordered hierarchical porous silica adsorbent according to claim 9 in the adsorption concentration of industrial high-air-volume low-concentration organic waste gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711183396.8A CN108101066B (en) | 2017-11-23 | 2017-11-23 | Preparation method and application of hydrophobic spherical ordered hierarchical porous silicon dioxide adsorbent |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711183396.8A CN108101066B (en) | 2017-11-23 | 2017-11-23 | Preparation method and application of hydrophobic spherical ordered hierarchical porous silicon dioxide adsorbent |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108101066A CN108101066A (en) | 2018-06-01 |
| CN108101066B true CN108101066B (en) | 2020-05-29 |
Family
ID=62206531
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711183396.8A Active CN108101066B (en) | 2017-11-23 | 2017-11-23 | Preparation method and application of hydrophobic spherical ordered hierarchical porous silicon dioxide adsorbent |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108101066B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2771045C1 (en) * | 2021-05-06 | 2022-04-25 | Федеральное государственное автономное образовательное учреждение высшего образования «Национальный исследовательский Томский государственный университет» | Sorption-catalytic material for neutralization of emissions of vocal organic compounds |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108786739A (en) * | 2018-07-04 | 2018-11-13 | 四川大学 | One kind having hydrophobic carbon-supported catalyst preparation method |
| CN110003137B (en) * | 2019-04-26 | 2021-06-29 | 江苏扬农化工集团有限公司 | Method for removing impurities in HPPO (high pressure propylene oxide) process by using silane coupling agent modified material |
| CN112076726A (en) * | 2019-06-12 | 2020-12-15 | 中国石油化工股份有限公司 | Mesoporous molecular sieve loaded with ionic liquid and preparation method and application thereof |
| CN110523390B (en) * | 2019-08-23 | 2021-08-10 | 华南理工大学 | Coffee residue adsorbent with hydrophobicity and preparation method thereof |
| CN112973637B (en) * | 2021-02-20 | 2022-06-21 | 杭州楠大环保科技有限公司 | High-efficiency waste gas treating agent and preparation method and application thereof |
| CN114377517A (en) * | 2021-11-22 | 2022-04-22 | 同济大学 | Coating waste gas purification system and method based on functional mesoporous silica rotating wheel |
| CN114272889A (en) * | 2021-12-30 | 2022-04-05 | 洛阳双罗铼材料科技有限公司 | Topological silicon dioxide for rhenium adsorption and preparation method and application thereof |
| CN114849677B (en) * | 2022-06-10 | 2024-01-26 | 重庆大学 | Phosphate adsorption material and preparation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102476803A (en) * | 2010-11-29 | 2012-05-30 | 国家纳米科学中心 | Surface-modified ordered mesoporous silicon dioxide composite material and its preparation method |
| CN103933929A (en) * | 2014-04-14 | 2014-07-23 | 华南理工大学 | Mesoporous silica adsorbent for adsorbing hydrophobic organic matters as well as preparation method and application of mesoporous silica adsorbent |
| CN104148021A (en) * | 2014-07-31 | 2014-11-19 | 桂林理工大学 | Method for preparing bifunctional mesoporous silica for adsorbing heavy metal ions in water |
| CN107128932A (en) * | 2017-05-04 | 2017-09-05 | 德清美联新材料科技有限公司 | A kind of preparation method for the VOC hydrophobic silicas adsorbed |
-
2017
- 2017-11-23 CN CN201711183396.8A patent/CN108101066B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102476803A (en) * | 2010-11-29 | 2012-05-30 | 国家纳米科学中心 | Surface-modified ordered mesoporous silicon dioxide composite material and its preparation method |
| CN103933929A (en) * | 2014-04-14 | 2014-07-23 | 华南理工大学 | Mesoporous silica adsorbent for adsorbing hydrophobic organic matters as well as preparation method and application of mesoporous silica adsorbent |
| CN104148021A (en) * | 2014-07-31 | 2014-11-19 | 桂林理工大学 | Method for preparing bifunctional mesoporous silica for adsorbing heavy metal ions in water |
| CN107128932A (en) * | 2017-05-04 | 2017-09-05 | 德清美联新材料科技有限公司 | A kind of preparation method for the VOC hydrophobic silicas adsorbed |
Non-Patent Citations (1)
| Title |
|---|
| Morphological Control of Highly Ordered Mesoporous Silica SBA-15;Dongyuan Zhao et al.;《Chem.Mater.》;20000202;第12卷;第275-279页 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2771045C1 (en) * | 2021-05-06 | 2022-04-25 | Федеральное государственное автономное образовательное учреждение высшего образования «Национальный исследовательский Томский государственный университет» | Sorption-catalytic material for neutralization of emissions of vocal organic compounds |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108101066A (en) | 2018-06-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108101066B (en) | Preparation method and application of hydrophobic spherical ordered hierarchical porous silicon dioxide adsorbent | |
| Bhagiyalakshmi et al. | Utilization of rice husk ash as silica source for the synthesis of mesoporous silicas and their application to CO2 adsorption through TREN/TEPA grafting | |
| Bhagiyalakshmi et al. | Synthesis of mesoporous magnesium oxide: Its application to CO2 chemisorption | |
| JP4134031B2 (en) | Method for the synthesis of mesoporous zeolite | |
| US6346140B2 (en) | Porous solid for gas adsorption separation and gas adsorption separation process employing it | |
| Zhao et al. | Enhancement of CO 2 adsorption and amine efficiency of titania modified by moderate loading of diethylenetriamine | |
| JP2008535756A (en) | Mesoporous particles | |
| JP5504446B2 (en) | Method for producing hydrophobic zeolite and hydrophobic zeolite obtained by the method | |
| CN111715205B (en) | Moisture-resistant catalyst for air pollution control and preparation method thereof | |
| CN107824172B (en) | Preparation method of nano alumina carrier with surface rich in defect sites | |
| Goscianska et al. | Equilibrium and kinetic studies of chromotrope 2R adsorption onto ordered mesoporous carbons modified with lanthanum | |
| CN112408402B (en) | Preparation method and application of La activated functionalized dendritic mesoporous silica nanosphere | |
| CN114272892B (en) | CO (carbon monoxide)2Trapping adsorbent and preparation method and application thereof | |
| CN112058235B (en) | Copper organic framework-silicon oxide porous composite material and preparation method and application thereof | |
| JP2001340755A (en) | Porous material for adsorbing and separating gas and method of adsorbing and separating gas using the same | |
| Zhou et al. | Dynamic adsorption of toluene on amino-functionalized SBA-15 type spherical mesoporous silica | |
| CN112694101B (en) | Core-shell molecular sieve, synthesis method and application thereof | |
| Abid et al. | Selective catalytic reduction of NO by NH3 on cerium modified faujasite zeolite prepared from aluminum scraps and industrial metasilicate | |
| Silva et al. | Modification of MCM-41 type structures by carbon deposition and acid washing for CO 2 adsorption | |
| CN113277520A (en) | Silicon dioxide mesoporous material and preparation method and application thereof | |
| CN110614086B (en) | Magnetic micelle and preparation method and application thereof | |
| KR20120079745A (en) | A absorbent comprising hydrophobic mesoporous material for removal of harmful pharmaceuticals from aqueous environment | |
| CN112892471A (en) | Preparation method of VOCs adsorbent molecular sieve with ultrahigh hydrophobic property | |
| Kaya | Polyethylene glycol/silica and carbon black/silica xerogel composites as an adsorbent for CO2capture | |
| Xu et al. | Fast and highly efficient SO 2 capture by TMG immobilized on hierarchical micro–meso–macroporous AlPO-5/cordierite honeycomb ceramic materials |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |