CN113058543A - Layered TiO imitating respiration-photosynthesis2Application of LDH adsorbent in degradation of organic pollutants in water body - Google Patents

Layered TiO imitating respiration-photosynthesis2Application of LDH adsorbent in degradation of organic pollutants in water body Download PDF

Info

Publication number
CN113058543A
CN113058543A CN202110364832.1A CN202110364832A CN113058543A CN 113058543 A CN113058543 A CN 113058543A CN 202110364832 A CN202110364832 A CN 202110364832A CN 113058543 A CN113058543 A CN 113058543A
Authority
CN
China
Prior art keywords
ldh
adsorbent
tio
layered
water
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.)
Pending
Application number
CN202110364832.1A
Other languages
Chinese (zh)
Inventor
胡京宇
杨喆
孔正
姚戎
潘玉航
沈意
宋爽
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University of Technology ZJUT
Original Assignee
Zhejiang University of Technology ZJUT
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Zhejiang University of Technology ZJUT filed Critical Zhejiang University of Technology ZJUT
Priority to CN202110364832.1A priority Critical patent/CN113058543A/en
Publication of CN113058543A publication Critical patent/CN113058543A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • 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
    • B01J20/06—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising oxides or hydroxides of metals not provided for in group B01J20/04
    • 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
    • B01J20/06—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising oxides or hydroxides of metals not provided for in group B01J20/04
    • B01J20/08—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising oxides or hydroxides of metals not provided for in group B01J20/04 comprising aluminium oxide or hydroxide; comprising bauxite
    • 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
    • B01J20/30—Processes for preparing, regenerating, or reactivating
    • B01J20/34—Regenerating or reactivating
    • B01J20/3433—Regenerating or reactivating of sorbents or filter aids other than those covered by B01J20/3408 - B01J20/3425
    • 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
    • B01J20/30—Processes for preparing, regenerating, or reactivating
    • B01J20/34—Regenerating or reactivating
    • B01J20/3441—Regeneration or reactivation by electric current, ultrasound or irradiation, e.g. electromagnetic radiation such as X-rays, UV, light, microwaves
    • 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
    • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
    • B01J21/10—Magnesium; Oxides or hydroxides thereof
    • 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
    • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
    • B01J21/20—Regeneration or reactivation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/288—Treatment of water, waste water, or sewage by sorption using composite sorbents, e.g. coated, impregnated, multi-layered
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/30—Treatment of water, waste water, or sewage by irradiation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/30—Organic compounds
    • C02F2101/308—Dyes; Colorants; Fluorescent agents
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/16—Regeneration of sorbents, filters
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/10—Photocatalysts

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • Toxicology (AREA)
  • Water Supply & Treatment (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Hydrology & Water Resources (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Health & Medical Sciences (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Abstract

The invention discloses layered TiO imitating respiration-photosynthesis2Application of LDH adsorbent in degrading organic pollutants in water body, wherein the adsorbent is TiO2The particles arePhotocatalyst, TiO22The particles are loaded on a layered magnalium double hydroxide LDH substrate to form layered TiO2a/LDH composite material. The adsorbent retains the original layered structure of LDH, and is layered with TiO after LDH2The composite, maximally contacts the surface of the LDH layer, and has the property of simulating 'respiration-photosynthesis'. The adsorbent provided by the invention overcomes the problem that the adsorption rate of the traditional adsorbent is limited by too slow regeneration kinetics, firstly enriches pollutants through adsorption, and then realizes the degradation of the pollutants and the regeneration of the adsorbent through photocatalysis under sunlight, thereby achieving the effect of recycling. The adsorbent has higher adsorption capacity on organic dye, and the adsorbent has compact structure and high pore density, so that the adsorbent improves the adsorption rate on pollutants and can be used in the fields of environmental protection, chemical industry and the like.

Description

Layered TiO imitating respiration-photosynthesis2Application of LDH adsorbent in degradation of organic pollutants in water body
Technical Field
The invention belongs to the technical field of material preparation, and particularly relates to layered TiO imitating respiration-photosynthesis2The application of the LDH adsorbent in degrading organic pollutants in water body.
Background
In recent years, organic pollution of surface water bodies in China is increasingly serious, pollution events are frequently reported, and water pollution treatment is urgent. However, the traditional water treatment technology (such as a reverse osmosis membrane method, an activated sludge method and the like) has high cost and great technical difficulty. The adsorption-regeneration method has universality for treating complex water bodies and low cost, and is very suitable for pollution control of natural water bodies. However, the adsorption efficiency and recovery process are greatly influenced by the micropores and granular morphology of the adsorption material (such as activated carbon, polyacrylamide, zeolite molecular sieve and the like). Meanwhile, the regeneration process mainly adopts high-temperature desorption or strong acid leaching, so that the energy consumption is high and the pollution is large. Therefore, the construction of the adsorption material which integrates strong adsorption and sunlight regeneration into a whole realizes the treatment of water pollution, and the adsorption material is expected to become an effective means for the innovation of the traditional water treatment process.
Disclosure of Invention
In view of the above problems in the prior art, it is an object of the present invention to provide a layered TiO imitating "respiration-photosynthesis2The LDH adsorbent has high adsorption capacity on organic dye, and has compact structure and high pore density, so that the adsorption rate on organic pollutant is greatly increased, and the strong antioxidant capacity of LDH in the adsorption-regeneration process improves the photocatalyst TiO2Light absorption efficiency of (1).
The layered TiO imitating respiration-photosynthesis2Use of/LDH adsorbent in degrading organic pollutant in water body, characterized in that the adsorbent is TiO2The particles are photocatalyst, TiO is added2The particles are loaded on a layered magnalium double hydroxide LDH substrate to form layered TiO2a/LDH composite material.
The layered TiO imitating respiration-photosynthesis2The application of the/LDH adsorbent in degrading organic pollutants in water is characterized in that the preparation method of the adsorbent comprises the following steps:
1) hydro-thermal synthesis of CO by urea hydrolysis method3 2-LDH, i.e. obtained as CO3 2-LDH materials as intercalation anions;
2) then using hydrochloric acid method to prepare CO3 2-Removing carbonate ions from LDH, and specifically comprising the following steps: 0.4 to 3.0g of CO obtained in step 1)3 2-Dispersing an LDH material in 400-600 mL of a dispersion containing 0.5-1.5M NaNO3And 2.0 to 4.0mM HNO3In the water solution, the nitrogen is used for purging and then sealing, and stirring reaction is carried out for 40-60 h at room temperature; after the reaction is finished, centrifugal separation is carried out, and the obtained solid is washed by water to obtain MgAlNO3LDH, labelling it as NO3-LDH materials;
3) subjecting NO obtained in step 2)3Mixing an LDH material and formamide according to a solid-liquid ratio of 0.001-0.003, wherein the unit of the solid-liquid ratio is g/mL, sealing after nitrogen purging, and carrying out ultrasonic treatment to form a colloidal suspension;
4) adding TiO into the mixture2According to 0.00Dispersing the solid-liquid ratio of 1-0.003 in formamide, wherein the unit of the solid-liquid ratio is g/mL to obtain TiO2A suspension; adding TiO into the mixture2Mixing the suspension with the colloidal suspension obtained in the step 3) according to a volume ratio of 0.2-0.4, stirring at room temperature for 20-30h, and then carrying out centrifugal separation, washing and drying to obtain the layered TiO2LDH adsorbent products.
The layered TiO imitating respiration-photosynthesis2The application of the/LDH adsorbent in degrading organic pollutants in water is characterized in that in the step 2), the room-temperature stirring reaction time is 45-50 h, the rotation speed of centrifugal separation is 8000-10000 rpm, and the centrifugal time is 8-12 minutes.
The layered TiO imitating respiration-photosynthesis2The application of the/LDH adsorbent in degrading organic pollutants in water is characterized in that in the step 3), the ultrasonic treatment time is 20-25 h.
The layered TiO imitating respiration-photosynthesis2The application of the/LDH adsorbent in degrading organic pollutants in water is characterized in that the organic dye is at least one of methyl orange and methylene blue.
The layered TiO imitating respiration-photosynthesis2The application of the LDH adsorbent in degrading organic pollutants in water is characterized in that the adsorbent is put into water containing organic dye, and after adsorption saturation is carried out under the condition of keeping out of the sun, the removal of the organic dye and the regeneration of the adsorbent are realized through solar radiation.
The layered TiO imitating respiration-photosynthesis2The application of the LDH adsorbent in degrading organic pollutants in water body is characterized in that in the step 1), CO is hydrothermally synthesized by adopting a urea hydrolysis method3 2-The specific steps of LDH are: mixing Mg (NO)3)2·6H2O、Al(NO3)3·9H2Dissolving O and urea in deionized water, stirring to form a transparent solution, then placing the transparent solution into a polytetrafluoroethylene high-pressure reaction kettle, reacting in an oven with the temperature of 130-150 ℃, filtering, washing filter residues with alcohol and water for several times, and drying to obtain CO3 2--LDH materials; wherein Mg (NO)3)2·6H2O、Al(NO3)3·9H2The mass ratio of the O to the urea is 1: 0.6-0.8: 1-1.2.
By adopting the technology, compared with the prior art, the invention has the following beneficial effects:
1) in order to simultaneously realize the removal of pollutants and the regeneration of an adsorbent, TiO is adopted2As a photocatalyst, Layered Double Hydroxide (LDH) is used as a substrate, and a typical urea hydrolysis hydrothermal method is adopted to synthesize CO3 2-LDH, followed by removal of carbonate ions, and TiO2Loading to prepare layered TiO/layered double hydroxide adsorbent, layered TiO2Compared with the original adsorbent, the LDH has the advantages of multiplied improvement of adsorption efficiency, higher adsorption performance and simulated respiration-photosynthesis property. Can realize the step-by-step proceeding of adsorption and regeneration so as to realize the organic pollution control of the water body.
2) The adsorbent product obtained by the invention not only has higher adsorption capacity to organic dyes in water, but also has repeatable regeneration capacity after light irradiation, compared with common titanium dioxide, the adsorbent product of the invention has higher photocatalysis efficiency of TiO loaded on LDH, the load of the adsorbent product can not change the layered structure of LDH, and the adsorbent product has high-efficiency light-assisted regeneration capacity. Experimental studies have found that the adsorption amount of the methyl orange is 235.08mg/g, 68.9% of regeneration rate is still achieved after 10h cycle regeneration, and the adsorption amount of the methylene blue is 135.20mg/g, 71.2% of regeneration rate is still achieved after 10h cycle regeneration. Due to the layered TiO of the invention2LDH has the characteristics of higher adsorption capacity and high-efficiency photo-assisted regeneration capability, and has great application potential in the fields of adsorption-photocatalysis, environmental protection and the like.
Drawings
FIG. 1 is a layered TiO produced in example 12One of the material scanning transmission electron micrographs of/LDH adsorbent material;
FIG. 2 is a layered TiO produced in example 12A second material scanning transmission electron microscope image of the/LDH adsorbent material;
FIG. 3 is a schematic view of an embodimentLayered TiO from example 12And the third material scanning transmission electron microscope image of the/LDH adsorbent material.
Detailed Description
The present invention is further illustrated by the following examples, which should not be construed as limiting the scope of the invention. The reagents or materials used in the present invention are commercially available products unless otherwise specified.
Example 1
In this example, layered titanium dioxide/layered double hydroxide (TiO) was prepared2The specific steps of the/LDH) composite material are as follows:
1) adopts urea hydrolysis method to hydrothermally synthesize CO3 2-LDH, i.e. obtained as CO3 2-LDH materials as intercalation anions; wherein, CO is hydrothermally synthesized by adopting a urea hydrolysis method3 2-The specific steps of LDH are: mixing Mg (NO)3)2·6H2O(1.20g)、Al(NO3)3·9H2Dissolving O (0.88g) and urea (1.31g) in 70ml deionized water, stirring for 30min to form a transparent solution, then putting the transparent solution into a 100ml polytetrafluoroethylene high-pressure reaction kettle, reacting in an oven at 140 ℃ for 24h, filtering, washing filter residues with alcohol and water for several times, and drying to obtain CO3 2--LDH materials;
2) then using hydrochloric acid method to prepare CO3 2-Removing carbonate ions from LDH, and specifically comprising the following steps: dispersing 0.5g of the pretreated LDH material obtained in step 1) to 500mL of a solution containing 1M NaNO3And 3.3 mM HNO3In the aqueous solution, sealing after nitrogen purging, and stirring at room temperature for reaction for 48 hours; after the reaction is finished, centrifugal separation is carried out (centrifugal separation is carried out for 10 minutes at 10000 rpm), and the obtained solid is washed by water to obtain MgAlNO3LDH, labelling it as NO3-LDH materials;
3) subjecting NO obtained in step 2)3Mixing 0.6g of LDH material with 300ml of formamide, sealing after nitrogen purging, and carrying out ultrasonic treatment for 22h to form a colloidal suspension;
4) 0.18g of TiO2Dispersing into 90ml of formamide to obtain TiO2A suspension; adding TiO into the mixture2Suspension and the colloid obtained in the step 3)Mixing the suspensions, stirring at room temperature for 24h, centrifuging at 2000rpm for 15min, discarding supernatant, washing with 100ml water, centrifuging at 6000rpm for 45min, washing with water for 3 times, and drying in air at 100 deg.C to obtain the layered TiO2LDH adsorbent products.
Example 2
In this example, a layered titanium oxide/layered double hydroxide (TiO) was prepared2The specific steps of the/LDH) composite material are as follows:
1) adopts urea hydrolysis method to hydrothermally synthesize CO3 2-LDH, i.e. obtained as CO3 2-LDH materials as intercalation anions; wherein, CO is hydrothermally synthesized by adopting a urea hydrolysis method3 2-The specific steps of LDH are: mixing Mg (NO)3)2·6H2O(1.20g)、Al(NO3)3·9H2Dissolving O (0.88g) and urea (1.31g) in 70ml deionized water, stirring for 30min to form a transparent solution, then putting the transparent solution into a 100ml polytetrafluoroethylene high-pressure reaction kettle, reacting in an oven at 140 ℃ for 24h, filtering, washing filter residues with alcohol and water for several times, and drying to obtain CO3 2--LDH materials;
2) then using hydrochloric acid method to prepare CO3 2-Removing carbonate ions from LDH, and specifically comprising the following steps: dispersing 1.0g of the pretreated LDH material obtained in step 1) to 500mL of a solution containing 1M NaNO3And 3.3 mM HNO3In the aqueous solution, sealing after nitrogen purging, and stirring at room temperature for reaction for 48 hours; after the reaction is finished, centrifugal separation is carried out (centrifugal separation is carried out for 10 minutes at 10000 rpm), and the obtained solid is washed by water to obtain MgAlNO3LDH, labelling it as NO3-LDH materials;
3) subjecting NO obtained in step 2)3Mixing 0.6g of LDH material with 300ml of formamide, sealing after nitrogen purging, and carrying out ultrasonic treatment for 22h to form a colloidal suspension;
4) 0.18g of TiO2Dispersing into 90ml of formamide to obtain TiO2A suspension; adding TiO into the mixture2Mixing the suspension with the colloidal suspension obtained in step 3), stirring at room temperature for 24h, centrifuging at 2000rpm for 15min, discarding the supernatant, washing with 100ml of water, centrifuging at 6000rpm for 45min, and repeating the above stepsWashing for 3 times, and drying in the air at 100 ℃ to obtain the layered TiO2LDH adsorbent products.
Example 3
In this example, layered titanium dioxide/layered double hydroxide (TiO) was prepared2The specific steps of the/LDH) composite material are as follows:
1) adopts urea hydrolysis method to hydrothermally synthesize CO3 2-LDH, i.e. obtained as CO3 2-LDH materials as intercalation anions; wherein, CO is hydrothermally synthesized by adopting a urea hydrolysis method3 2-The specific steps of LDH are: mixing Mg (NO)3)2·6H2O(1.20g)、Al(NO3)3·9H2Dissolving O (0.88g) and urea (1.31g) in 70ml deionized water, stirring for 30min to form a transparent solution, then putting the transparent solution into a 100ml polytetrafluoroethylene high-pressure reaction kettle, reacting in an oven at 140 ℃ for 24h, filtering, washing filter residues with alcohol and water for several times, and drying to obtain CO3 2--LDH materials;
2) then using hydrochloric acid method to prepare CO3 2-Removing carbonate ions from LDH, and specifically comprising the following steps: dispersing 1.5g of the pretreated LDH material obtained in step 1) to 500mL of a solution containing 1M NaNO3And 3.3 mM HNO3In the aqueous solution, sealing after nitrogen purging, and stirring at room temperature for reaction for 48 hours; after the reaction is finished, centrifugal separation is carried out (centrifugal separation is carried out for 10 minutes at 10000 rpm), and the obtained solid is washed by water to obtain MgAlNO3LDH, labelling it as NO3-LDH materials;
3) subjecting NO obtained in step 2)3Mixing 0.6g of LDH material with 300ml of formamide, sealing after nitrogen purging, and carrying out ultrasonic treatment for 22h to form a colloidal suspension;
4) 0.18g of TiO2Dispersing into 90ml of formamide to obtain TiO2A suspension; adding TiO into the mixture2Mixing the suspension with the colloidal suspension obtained in the step 3), stirring at room temperature for 24h, centrifuging at 2000rpm for 15min, discarding the supernatant, washing with 100ml of water, centrifuging at 6000rpm for 45min, washing with water for 3 times, and drying in the air at 100 ℃ to obtain the layered TiO2LDH adsorbent products.
Example 4
In this example, layered titanium dioxide/layered double hydroxide (TiO) was prepared2The specific steps of the/LDH) composite material are as follows:
1) adopts urea hydrolysis method to hydrothermally synthesize CO3 2-LDH, i.e. obtained as CO3 2-LDH materials as intercalation anions; wherein, CO is hydrothermally synthesized by adopting a urea hydrolysis method3 2-The specific steps of LDH are: mixing Mg (NO)3)2·6H2O(1.20g)、Al(NO3)3·9H2Dissolving O (0.88g) and urea (1.31g) in 70ml deionized water, stirring for 30min to form a transparent solution, then putting the transparent solution into a 100ml polytetrafluoroethylene high-pressure reaction kettle, reacting in an oven at 140 ℃ for 24h, filtering, washing filter residues with alcohol and water for several times, and drying to obtain CO3 2--LDH materials;
2) then using hydrochloric acid method to prepare CO3 2-Removing carbonate ions from LDH, and specifically comprising the following steps: dispersing 2.0g of the pretreated LDH material obtained in step 1) to 500mL of a solution containing 1M NaNO3And 3.3 mM HNO3In the aqueous solution, sealing after nitrogen purging, and stirring at room temperature for reaction for 48 hours; after the reaction is finished, centrifugal separation is carried out (centrifugal separation is carried out for 10 minutes at 10000 rpm), and the obtained solid is washed by water to obtain MgAlNO3LDH, labelling it as NO3-LDH materials;
3) subjecting NO obtained in step 2)3Mixing 0.6g of LDH material with 300ml of formamide, sealing after nitrogen purging, and carrying out ultrasonic treatment for 22h to form a colloidal suspension;
4) 0.18g of TiO2Dispersing into 90ml of formamide to obtain TiO2A suspension; adding TiO into the mixture2Mixing the suspension with the colloidal suspension obtained in the step 3), stirring at room temperature for 24h, centrifuging at 2000rpm for 15min, discarding the supernatant, washing with 100ml of water, centrifuging at 6000rpm for 45min, washing with water for 3 times, and drying in the air at 100 ℃ to obtain the layered TiO2LDH adsorbent products.
Example 5
In this example, layered titanium dioxide/layered double hydroxide (TiO) was prepared2/LDH) complexationThe specific steps of the material are as follows:
1) adopts urea hydrolysis method to hydrothermally synthesize CO3 2-LDH, i.e. obtained as CO3 2-LDH materials as intercalation anions; wherein, CO is hydrothermally synthesized by adopting a urea hydrolysis method3 2-The specific steps of LDH are: mixing Mg (NO)3)2·6H2O(1.20g)、Al(NO3)3·9H2Dissolving O (0.88g) and urea (1.31g) in 70ml deionized water, stirring for 30min to form a transparent solution, then putting the transparent solution into a 100ml polytetrafluoroethylene high-pressure reaction kettle, reacting in an oven at 140 ℃ for 24h, filtering, washing filter residues with alcohol and water for several times, and drying to obtain CO3 2--LDH materials;
2) then using hydrochloric acid method to prepare CO3 2-Removing carbonate ions from LDH, and specifically comprising the following steps: dispersing 2.5g of the pretreated LDH material obtained in step 1) to 500mL of a solution containing 1M NaNO3And 3.3 mM HNO3In the aqueous solution, sealing after nitrogen purging, and stirring at room temperature for reaction for 48 hours; after the reaction is finished, centrifugal separation is carried out (centrifugal separation is carried out for 10 minutes at 10000 rpm), and the obtained solid is washed by water to obtain MgAlNO3LDH, labelling it as NO3-LDH materials;
3) subjecting NO obtained in step 2)3Mixing 0.6g of LDH material with 300ml of formamide, sealing after nitrogen purging, and carrying out ultrasonic treatment for 22h to form a colloidal suspension;
4) 0.18g of TiO2Dispersing into 90ml of formamide to obtain TiO2A suspension; adding TiO into the mixture2Mixing the suspension with the colloidal suspension obtained in the step 3), stirring at room temperature for 24h, centrifuging at 2000rpm for 15min, discarding the supernatant, washing with 100ml of water, centrifuging at 6000rpm for 45min, washing with water for 3 times, and drying in the air at 100 ℃ to obtain the layered TiO2LDH adsorbent products.
For the layered TiO obtained in example 12The results of transmission electron microscopy scanning of the/LDH powder are shown in FIGS. 1 to 3. As can be seen from FIGS. 1-3, layered TiO2The structure of the/LDH is compact, most of the LDH appears in an aggregated form, the layered structure of the LDH is reserved, the pore density is high, and the content of the LDH is greatly increasedThe adsorption rate of the pollutants is high.
Layered TiO prepared using example 12the/LDH adsorbent product is subjected to an isothermal adsorption experiment.
Layered TiO prepared in example 12Adsorption experiment process of/LDH adsorbent on methylene blue: at 25 ℃, adding 1.0mg of adsorbent into 6 parts of conical bottles with stoppers respectively, then adding 100ml of methylene blue aqueous solution with the concentration of 0, 4, 8, 12, 16 and 20mg/L respectively, and placing the bottles in a constant-temperature shaking table at 25 ℃ and keeping out of the sun to adsorb at 120 r/min. After 4h, the sample was taken, passed through a microporous filter, and the residual concentration C of methylene blue in the solution after adsorption was measured by a two-beam UV-visible spectrophotometer (Persee T6-1650E)t。
Layered TiO prepared in example 12Adsorption experiment process of methyl orange by LDH adsorbent: at 25 ℃, 1.0mg of adsorbent is respectively added into 7 parts of conical bottles with stoppers, then 100ml of methyl orange aqueous solution with the concentration of 0, 10, 20, 30, 40, 50 and 60mg/L is respectively added, and the mixture is respectively placed in a constant temperature shaking table at 25 ℃ and is oscillated and adsorbed at 120 r/min. After 4h, sampling, passing through a microporous filter membrane, and measuring the residual concentration C of methyl orange in the adsorbed solution by using a two-beam ultraviolet-visible spectrophotometer (Persee T6-1650E)t。
In the course of the above experiment, the layered TiO prepared in example 1 was used2When methyl orange and methylene blue are adsorbed by the/LDH adsorbent, the Langmuir and Freundlich isothermal adsorption models are adopted for fitting, and the parameter results of fitting are shown in the table 1.
TABLE 1 layered TiO2Freundlich and Languuir isothermal adsorption parameters of/LDH on organic dyes
Figure BDA0003006964510000101
In Table 1, qmThe theoretical saturated adsorption capacity of the adsorbent to the organic dye is shown in the unit of mg/g; kLAdsorption constant for Langmuir model; kfAnd n are the adsorption constants of the Freundlich model; r2Is Langmuir model or Freundlicorrelation coefficient of ch model.
As can be seen from table 1: layered TiO prepared in example 12When the/LDH adsorbent adsorbs methyl orange and methylene blue, the correlation coefficients fitted by a Langmuir adsorption model are higher than those fitted by a Freundlich adsorption model, and the results show that the organic dye adsorbs layered TiO2Adsorption by/LDH non-carbon based adsorbents tends to be monolayer rather than multilayer adsorption. Layered TiO2The adsorption capacity (235.08mg/g) of the negative methyl orange by the/LDH non-carbon-based adsorbent is much higher than that (135.20mg/g) of the positive methylene blue. Layered TiO as compared to the adsorption capacity of other carbon-based adsorbents2LDH exhibits excellent adsorption properties: for example, see document 1, "Yangye, Chenglang, Guanzhan, et al. study of adsorption kinetics of activated carbon fiber ACF on methyl orange dye [ J]Guangzhou chemical 2020, (1):66-68 "discloses the technical content that the theoretical saturated adsorption capacity q of the activated carbon fiber to methyl orange ism294.12 mg/g; see document 2 "Timen. modification of semi-coke and study on adsorption property of dye in wastewater [ D]Combined fertilizer in 2016, the theoretical saturated adsorption quantity q of semi-coke material to methylene bluem＝40.8mg/g)。
Application example 2:
layered TiO prepared using example 12the/LDH adsorbent was subjected to kinetic adsorption experiments.
Dynamic adsorption experiments were performed on methylene blue: 100ml of methylene blue solution with the concentration of 5mg/L is measured and put into a 250ml conical flask with a plug, 1.0mg of adsorbent is accurately weighed and added into the conical flask, and the conical flask is put into a light-proof constant temperature shaking table with the temperature of 25 ℃ to be vibrated and adsorbed at the speed of 120 r/min. Sampling at 15min intervals, passing through a microporous filter membrane, and measuring the residual concentration C of the dye in the solutiont。
Dynamic adsorption experiments were performed on methyl orange: 100ml of 20mg/L methyl orange solution is weighed into a 250ml conical flask with a plug, 1.0mg of adsorbent is accurately weighed into the conical flask, and the conical flask is placed into a light-proof constant-temperature shaking table at 25 ℃ to be vibrated and adsorbed at 120 r/min. Sampling at 15min intervals, passing through a microporous filter membrane, and measuring the residual concentration C of the dye in the solutiont。
By simulatingHierarchical TiO with two-level and quasi-two-level dynamics model2The processes of methyl orange and methylene blue adsorption by the/LDH adsorbent are respectively fitted, and the experimental results are shown in Table 2. In Table 2, k1Is a quasi-first order rate constant with the unit of 1/s; k is a radical of2Is a quasi-second order rate constant in units of g/(mg · s); q. q.seTo balance the adsorption, mg/g.
TABLE 2 layered TiO2Adsorption kinetics parameters of LDH on organic dyes
Figure BDA0003006964510000111
As can be seen from table 2: layered TiO with quasi-two-stage kinetic equation2The correlation coefficient for the adsorption of two organic dyes by the/LDH material is larger than the equation of first order kinetics, which means that the adsorption mechanism for the two pollutants may be the same. LDH delamination leaves the surface of the LDH layer exposed for easy adsorption in the bulk phase.
Application example 3:
the adsorbent obtained in example 1 was used to carry out a light-assisted regeneration experiment. The experimental process comprises the following steps: 15mg of pre-adsorbing material (the pre-adsorbing material is layered TiO saturated in methylene blue adsorption)2LDH material, or layered TiO saturated in methyl orange adsorption2/LDH material) in 15ml of deionized water, stirred with a magnetic stirrer and passed through a low-pressure mercury lamp (16 mW/cm)2) The sample solution is irradiated. A quantitative suspension is taken out at a certain time, and a sample of the suspension is acidified by 15ml of hydrochloric acid with a concentration of 1mol/L to elute the dye remaining in the suspension (the solubility to LDH after acidification is negligible). After passing through a microporous filter membrane, detecting the concentration of the dye in the supernatant, estimating the percentage of the available adsorption sites after photocatalytic degradation by obtaining the residual amount of the dye in the adsorption of the composite material after different irradiation times, and estimating the photo-assisted regeneration kinetics of the composite material. The results are shown in Table 3, where Table 3 shows layered TiO2Experimental results of regeneration kinetic parameters of LDH materials to organic dyes. The material with saturated methylene blue adsorption completes more than 50.6 percent of regeneration within 2 hours, and reaches 60.7 percent of regeneration after 4 hours. Methyl orange saturated in adsorptionLayered TiO2the/LDH material can complete more than 48.6 percent of regeneration within 2 hours, and achieves 62.8 percent of regeneration after 4 hours. Methyl orange adsorption saturated layered TiO2the/LDH material also maintained a regeneration rate of 68.9% after 10h of cyclic regeneration adsorption. TiO saturated by methylene blue adsorption2The regeneration rate of the/LDH material is still kept above 71.2 percent after 10 hours of cyclic regeneration. The absorption efficiency of the photocatalyst TiO2 is improved in the adsorption-regeneration process due to the strong oxidation resistance of the LDH.
TABLE 3 layered TiO2Regeneration kinetic parameters of/LDH on organic dyes
Figure BDA0003006964510000121
Comparative example 1
In the method for adsorbing anionic and cationic pollutants in water by using the layered double hydroxide composite adsorbing material disclosed in the Chinese patent 111001375A, the layered double hydroxide is compounded with a macroscopic adsorbing material to improve the adsorbing effect on the pollutants, and the adsorbed pollutants can be removed in situ after organisms are attached to the composite material. The adsorbing material is prepared by compounding a layered double hydroxide nano material with a traditional adsorbing material such as activated carbon, a ceramsite filter material and the like, and the anion adsorption characteristic of the layered double hydroxide material and the adsorption capacity of the traditional adsorbing material are utilized to realize simultaneous adsorption of anion and cation pollutants in water. The conditions that the method needs to control are various and complicated, and comprise:
step 1) weighing divalent metal salt and trivalent metal salt which form layered double hydroxide and are mixed and dissolved in water to obtain mixed salt solution, wherein the molar ratio of the divalent metal salt to the trivalent metal salt is 1:1-3: 1; dissolving anhydrous sodium carbonate and sodium hydroxide in water to prepare mixed alkali liquor; dropping the mixed alkali liquor into the mixed salt solution until the pH value is 10;
step 2) adding an adsorbing material into the mixed salt solution, and stirring at the rotating speed of 1000-1400 r/min to load layered double hydroxide on the surface and in the micropores of the adsorbing material; after the reaction is finished, keeping the rotating speed and continuously stirring for a period of time for aging;
and 3) separating the product in a centrifugal mode, cleaning the product and drying the product to obtain the layered double hydroxide composite adsorbing material.
In addition, the composite material has high unstable factors in the mode of utilizing microorganisms to achieve adsorption point position regeneration, the activity of the microorganisms is restricted by water body factors, the death or excessive reproduction of the microorganisms can bring adverse effects on the water purification result, and the long-term stable operation cost is not controllable, so that the good adsorption-regeneration effect is difficult to realize.
Compared with the preparation process of the adsorbing material in the comparative example 1, the method of the adsorbing material has obvious advantages in the synthesis process, and particularly has the following advantages:
firstly, the production cost is lower, and the production efficiency is higher. The adsorption material has the oxidation resistance and the light transmittance, can avoid the reduction of the light quantum efficiency caused by the attack of active oxygen and the light absorption of the substrate in the photocatalysis process, and ensures the long-term stable operation and controllable cost. And in addition, the production process of the adsorbing material disclosed by the invention has no metal raw material, and strong base is not required to be added, so that the environmental risks caused by metal leaching and strong base are reduced. The product has higher adsorption capacity and high-efficiency photo-assisted regeneration capacity, artificial calcination regeneration is not needed, the efficiency of degrading organic dye in water is greatly improved, meanwhile, the self-regeneration of the adsorption point position is realized by utilizing renewable sunlight resources, and high efficiency, energy conservation and environmental protection are really realized.
The statements in this specification merely set forth a list of implementations of the inventive concept and the scope of the present invention should not be construed as limited to the particular forms set forth in the examples.

Claims (7)

1. Layered TiO imitating respiration-photosynthesis2Use of/LDH adsorbent in degrading organic pollutant in water body, characterized in that the adsorbent is TiO2The particles are photocatalyst, TiO is added2The particles are loaded on a layered magnalium double hydroxide LDH substrate to form layered TiO2a/LDH composite material.
2. The 'breath-photosynthesis' -mimicking layered TiO of claim 12The application of the/LDH adsorbent in degrading organic pollutants in water is characterized in that the preparation method of the adsorbent comprises the following steps:
1) hydro-thermal synthesis of CO by urea hydrolysis method3 2−LDH, i.e. obtained as CO3 2−LDH materials as intercalation anions;
2) then using hydrochloric acid method to prepare CO3 2−Removing carbonate ions from LDH, and specifically comprising the following steps: 0.4 to 3.0g of CO obtained in step 1)3 2−Dispersing an LDH material in 400-600 mL of a dispersion containing 0.5-1.5M NaNO3And 2.0 to 4.0mM HNO3In the water solution, the nitrogen is used for purging and then sealing, and stirring reaction is carried out for 40-60 h at room temperature; after the reaction is finished, centrifugal separation is carried out, and the obtained solid is washed by water to obtain MgAlNO3LDH, labelling it as NO3-LDH materials;
3) subjecting NO obtained in step 2)3Mixing an LDH material and formamide according to a solid-liquid ratio of 0.001-0.003, wherein the unit of the solid-liquid ratio is g/mL, sealing after nitrogen purging, and carrying out ultrasonic treatment to form a colloidal suspension;
4) adding TiO into the mixture2Dispersing the mixture into formamide according to a solid-liquid ratio of 0.001-0.003, wherein the unit of the solid-liquid ratio is g/mL, and obtaining TiO2A suspension; adding TiO into the mixture2Mixing the suspension with the colloidal suspension obtained in the step 3) according to a volume ratio of 0.2-0.4, stirring at room temperature for 20-30h, and then carrying out centrifugal separation, washing and drying to obtain the layered TiO2LDH adsorbent products.
3. The 'breath-photosynthesis' -mimicking layered TiO of claim 22The application of the/LDH adsorbent in degrading organic pollutants in water is characterized in that in the step 2), the room-temperature stirring reaction time is 45-50 h, the rotation speed of centrifugal separation is 8000-10000 rpm, and the centrifugal time is 8-12 minutes.
4. The 'breath-photosynthesis' -mimicking layered TiO of claim 22The application of the/LDH adsorbent in degrading organic pollutants in water is characterized in that in the step 3), the ultrasonic treatment time is 20-25 h.
5. The 'breath-photosynthesis' -mimicking layered TiO of claim 12The application of the/LDH adsorbent in degrading organic pollutants in water is characterized in that the organic dye is at least one of methyl orange and methylene blue.
6. The 'breath-photosynthesis' -mimicking layered TiO of claim 12The application of the LDH adsorbent in degrading organic pollutants in water is characterized in that the adsorbent is put into water containing organic dye, and after adsorption saturation is carried out under the condition of keeping out of the sun, the removal of the organic dye and the regeneration of the adsorbent are realized through solar radiation.
7. The 'breath-photosynthesis' -mimicking layered TiO of claim 22The application of the LDH adsorbent in degrading organic pollutants in water body is characterized in that in the step 1), CO is hydrothermally synthesized by adopting a urea hydrolysis method3 2−The specific steps of LDH are: mixing Mg (NO)3)2·6H2O、Al(NO3)3·9H2Dissolving O and urea in deionized water, stirring to form a transparent solution, then placing the transparent solution into a polytetrafluoroethylene high-pressure reaction kettle, reacting in an oven with the temperature of 130-150 ℃, filtering, washing filter residues with alcohol and water for several times, and drying to obtain CO3 2−-LDH materials; wherein Mg (NO)3)2·6H2O、Al(NO3)3·9H2The mass ratio of the O to the urea is 1: 0.6-0.8: 1-1.2.
CN202110364832.1A 2021-04-06 2021-04-06 Layered TiO imitating respiration-photosynthesis2Application of LDH adsorbent in degradation of organic pollutants in water body Pending CN113058543A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110364832.1A CN113058543A (en) 2021-04-06 2021-04-06 Layered TiO imitating respiration-photosynthesis2Application of LDH adsorbent in degradation of organic pollutants in water body

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110364832.1A CN113058543A (en) 2021-04-06 2021-04-06 Layered TiO imitating respiration-photosynthesis2Application of LDH adsorbent in degradation of organic pollutants in water body

Publications (1)

Publication Number Publication Date
CN113058543A true CN113058543A (en) 2021-07-02

Family

ID=76565963

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110364832.1A Pending CN113058543A (en) 2021-04-06 2021-04-06 Layered TiO imitating respiration-photosynthesis2Application of LDH adsorbent in degradation of organic pollutants in water body

Country Status (1)

Country Link
CN (1) CN113058543A (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108514888A (en) * 2018-04-16 2018-09-11 北京化工大学 A kind of preparation of polyacid intercalation hydrotalcite catalysis material and photocatalysis deep desulfurization of fuel oil system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108514888A (en) * 2018-04-16 2018-09-11 北京化工大学 A kind of preparation of polyacid intercalation hydrotalcite catalysis material and photocatalysis deep desulfurization of fuel oil system

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
胡京宇等: "可光助再生二氧化钛/层状双氢氧化物去除水体中有机染料", 《化工学报》 *
马辉等: "MgAl-LDH的去碳酸化-二步酸盐法制备NO3型LDH", 《北京师范大学学报（自然科学版）》 *

Similar Documents

Publication Publication Date Title
US11642649B2 (en) Method for preparing biochar from phosphoric acid-modified Enteromorpha prolifera, and use of biochar in removal of cadmium
CN109126893B (en) Titanium oxycarbide-metal organic framework composite material, and preparation method and application thereof
US20180291266A1 (en) A carbon quantum dot synthesizing method and its application of modifying functional water purification material
CN105148964B (en) A kind of three-dimensional redox graphene Mn3O4/MnCO3Nano composite material and preparation method thereof
CN110124655B (en) Zinc oxide/carbon quantum dot composite photocatalyst and preparation method and application thereof
CN112915972A (en) high-Cr (VI) adsorption amount core-shell structure high-molecular magnetic nanosphere and preparation method and application thereof
CN112521617B (en) Polyacid-based metal organic framework material for adsorbing antibiotics and preparation method and application thereof
CN111545246A (en) Preparation method of nano composite photocatalyst AgCl/ZIF-8 and nano composite photocatalyst prepared by same
CN111530490A (en) Co3O4-TiO2Heterojunction loaded carbon nanotube photocatalytic degradation material and preparation method thereof
CN112452292B (en) Composite manganese oxide adsorption material and preparation method and application thereof
CN113145174B (en) Coordination modulator modified iron-based metal organic framework porous composite material and preparation method and application thereof
CN110064407A (en) Biological preparation method based on zinc-manganese ferrite loaded nano copper sulfide
CN110624534A (en) Biological genetic WO3Photocatalyst and preparation method and application thereof
Li et al. Adsorption of heavy metals and antibacterial activity of silicon-doped chitosan composite microspheres loaded with ZIF-8
CN111135839B (en) Iron oxide modified attapulgite/bismuth molybdate composite photocatalyst and preparation method and application thereof
CN109095546B (en) Method for preparing hydrogen by cooperation of photocatalytic treatment of wastewater
CN112973744A (en) Novel photoelectric catalyst and preparation method thereof
CN108940348B (en) Silver chromate/sulfur-doped nitrogen carbon Z-type photocatalyst and preparation method thereof
CN114950358B (en) Manganese-titanium oxide-biomass charcoal composite material and preparation method and application thereof
CN107486203B (en) Recyclable floating type composite photocatalytic ball and preparation method and application thereof
CN113058543A (en) Layered TiO imitating respiration-photosynthesis2Application of LDH adsorbent in degradation of organic pollutants in water body
Wang et al. Efficient adsorption of tetracycline from aqueous solution using copper and zinc oxides modified porous boron nitride adsorbent
CN110302768B (en) Diatomaceous earth/TiO2Composite photocatalyst and preparation method and application thereof
CN113578265A (en) Preparation and application method of modified corncob biochar adsorbent
CN109529774B (en) Graphene oxide-terbium hydroxide composite material, preparation method and application thereof

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
RJ01 Rejection of invention patent application after publication

Application publication date: 20210702

RJ01 Rejection of invention patent application after publication