A method for preparing porous adsorption material using Pickering emulsion stabilized by olive pomace as template

Abstract

The invention belongs to the technical field of polymer material manufacturing, and particularly relates to a method for preparing a porous adsorption material using a Pickering emulsion stabilized by olive pomace as a template, comprising the following steps: crushing the olive pomace, passing through a 10-600 mesh sieve, and then dispersing in water; adding a functional monomer, a crosslinking agent, and an initiator and stirring evenly, then adding an organic solvent and stirring at 100-500 rpm to form an emulsion, and then polymerizing at 50-90 DEG C for 4-24 hours; after the reaction is completed, extracting with acetone Soxhlet for 12-48 hours, and drying at 40-105 DEG C to obtain a porous adsorption material; the method has the following beneficial effects: the method uses olive pomace as Pickering emulsion stabilized particles, and uses the emulsion as a template to polymerize functional monomers in a continuous phase, and then extracting and drying with Soxhlet, so that the prepared adsorption material has rich internal pore structure, good mechanical strength, good adsorption effect on heavy metals, anionic dyes and cationic dyes, fast adsorption rate, and high adsorption capacity.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer material manufacturing, and in particular relates to a method for preparing a porous adsorption material using a Pickering emulsion stabilized by olive pomace as a template, which is mainly used for adsorbing anions / cations and heavy metal pollutants in wastewater. Background Art

[0002] Olive, also known as olive and olea europaea, is an evergreen tree belonging to the family Oleaceae and the genus Olea. It is a world-famous evergreen woody oil and fruit oil. It is widely planted in Gansu, Shaanxi, Yunnan, Sichuan and other provinces in my country. It has the characteristics of long life, high yield and high oil content. Its fresh fruit can be directly pressed for oil or made into preserved fruit. The oil content of olive fruit is 30%. According to statistics, 35 to 40 kg of pomace will be produced after 100 kg of fresh olive fruit is pressed for oil. Except for a very small part of these pomace used as fertilizer or feed, most of them are directly discarded, which not only seriously pollutes the environment, but also causes a waste of resources.

[0003] Secondly, porous adsorption materials have very broad application prospects in the fields of water treatment and adsorption separation due to their rich internal pore structure, fully exposed adsorption groups, and low mass transfer resistance. In particular, porous materials constructed by the emulsion template method have attracted widespread attention in the industry because their porous structure can be adjusted through experimental parameters, the preparation process is simple, and the adsorption performance can be designed. Using water-in-oil emulsions as templates is an important method for constructing porous materials. Among them, Pickering emulsions are emulsions stabilized by particles instead of surfactants, and their emulsion stability is good. In recent years, the research on stabilizing pickerling emulsions with solid waste particles instead of synthetic particles has become an important direction for the development of this field. Using waste particle-stabilized Pickering emulsions as templates to construct porous adsorption materials not only greatly reduces the preparation cost of emulsions and porous materials, but also realizes the efficient reuse of waste, so it is of great significance. Olive pomace contains polymerizable macromolecular aggregates such as polyphenols, hydroxytyrosol and lignin cellulose, which can be used as solid particles instead of synthetic particles to prepare Pickering emulsions, but there is no report on the use of olive pomace to prepare porous adsorption materials through Pickering emulsions. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing a porous adsorption material using a Pickering emulsion stabilized by olive pomace as a template, and at the same time to study the adsorption performance of the constructed porous adsorption material for dye molecules and heavy metal ions.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A method for preparing a porous adsorption material using a Pickering emulsion stabilized by olive pomace as a template, characterized in that it comprises the following steps:

[0007] Step 1: Crush the olive pomace, pass it through a 10-600 mesh sieve, and then disperse it into water;

[0008] Step 2: Add functional monomer, crosslinking agent, initiator and stir evenly, then add organic solvent and stir at 100-500 rpm to form emulsion, and then polymerize at 50-90°C for 4-24h;

[0009] Step 3: After the reaction is completed, use acetone Soxhlet to extract for 12 to 48 hours, and dry at 40 to 105°C to obtain a porous adsorption material.

[0010] Preferably, in step 1, the mass percentage of the treated olive pomace dispersed in water is 0.5 to 19%.

[0011] Preferably, in step 2, the functional monomers are at least two of methacrylic acid, methyl methacrylate, acrylonitrile, styrene, butyl acrylate, 2-acrylamido-2-methylpropanesulfonic acid, allylthiourea, 2-ethylhexyl acrylate, dimethylaminoethyl methacrylate, acrylic acid, and 3-(dimethylamino)ethyl acrylate; and the added amount of the functional monomers is 10 to 35 times the mass of the olive pomace.

[0012] Preferably, in step 2, the cross-linking agent is at least one of triallyl isocyanate, N,N'-methylenebisacrylamide, divinylbenzene, ethylene glycol dimethacrylate, trimethylolpropane triacrylate, and trimethylolpropane trimethacrylate; and the amount of the cross-linking agent added is 1.5 to 8 times the mass of the olive pomace.

[0013] Preferably, in step 2, the initiator is one of potassium persulfate, ammonium persulfate, azobisisobutylnitrile, azobisisoheptylnitrile, cumene hydroperoxide, p-menthane hydroperoxide, and benzoyl peroxide; and the amount of the initiator added is 1 to 4.5 times the mass of the olive pomace.

[0014] Preferably, in step 2, the organic solvent is one of acetone, ethanol, n-hexane, n-octane, xylene, cyclohexane, olive oil, soybean oil, linolenic acid oil, and corn oil; and the volume ratio of the organic solvent to water is 1:0.3 to 1:50.

[0015] Compared with the prior art, the invention has the following beneficial effects: the invention uses olive pomace as Pickering emulsion-stabilized particles, uses the emulsion as a template, polymerizes functional monomers in a continuous phase, and then extracts and dries the particles through Soxhlet extraction, thereby obtaining an adsorption material with rich internal pore structure and good mechanical strength, and has a good adsorption effect on heavy metals, anionic dyes and cationic dyes, and has a fast adsorption rate and a high adsorption capacity, and can be widely used in the fields of heavy metal pollution, dye wastewater treatment, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is an optical microscope photo of the pomace-stabilized Pickering emulsion prepared by the present invention;

[0017] Figure 2 This is the SEM image of the porous material constructed using the Pickering emulsion stabilized by pomace as a template;

[0018] Figure 3 Figure 2 shows the adsorption capacity of anionic / cationic dyes and heavy metals for porous materials constructed using Pickering emulsion stabilized by pomace as template. Figure 3 a is dye, Figure 3 b is heavy metal);

[0019] Figure 4 The adsorption rate of anionic / cationic dyes and heavy metals on the porous material constructed with Pickering emulsion stabilized by pomace as template ( Figure 4 a is dye, Figure 4 b is heavy metal). DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] 1. Morphology and structure of porous multifunctional adsorption materials

[0022] The structural morphology of the porous adsorbent prepared by the present invention is analyzed by scanning electron microscopy (SEM) and other characterization methods.

[0023] 1. Optical microscope analysis

[0024] Figure 1The optical microscope photo of the olive pomace stabilized Pickering emulsion prepared by the present invention. It was observed under an optical microscope that the diameter of the formed Pickering emulsion droplets was about 5 μm. A small amount of pomace particles agglomerated, but most of the pomace was evenly distributed and fixed on the oil-water two-phase interface, indicating that the pomace has good amphiphilicity and can be used to stabilize the emulsion without adding a surfactant.

[0025] 2. SEM analysis

[0026] Figure 2 This is a SEM image of the porous adsorption material prepared by the present invention. It can be observed that the porous material has a rich pore structure inside, and the pore structure has good connectivity. The primary pore diameter is about 10-20um, and the connected pore diameter is about 3-10um. o

[0027] 2. Adsorption performance of porous multifunctional adsorption materials

[0028] 1. Adsorption capacity for heavy metals and anionic / cationic dyes

[0029] Figure 3 The porous adsorption material prepared by the present invention is for heavy metal ions Cu 2+ , Pb 2+ and the adsorption capacity of organic cationic dye methylene blue and anionic dye acid fuchsin ( Figure 3 a is dye, Figure 3 b is heavy metal). Figure 3 It can be seen that the maximum adsorption capacity of the porous adsorption material for methylene blue and acid fuchsin is 101.25 mg / g and 251.28 mg / g, respectively, and for Cu 2+ , Pb 2+ The maximum adsorption amounts were 123.58 mg / g and 207.13 mg / g respectively.

[0030] 2. Adsorption rate of heavy metals and anionic / cationic dyes

[0031] Figure 4 The adsorption rate curve of the porous adsorbent prepared by the present invention for heavy metals and anionic / cationic dyes ( Figure 4 a is dye, Figure 4 b is heavy metal). As can be seen from the figure, the adsorption of anionic / cationic dyes and heavy metals by the porous adsorption material can be completed within 50min and 30min respectively, showing a faster adsorption rate.

[0032] Example 1

[0033] The olive pomace was crushed and passed through a 100-mesh sieve; 1g of olive pomace was dispersed in 16mL of water and dispersed evenly under 500rpm stirring; 10g of 2-acrylamido-2-methylpropanesulfonic acid, 16g of allylthiourea, 3g of N,N'-methylenebisacrylamide, and 1g of ammonium persulfate were taken and dispersed evenly; 53mL of xylene was added and stirred at 500rpm to form an emulsion, and then polymerized at 50℃ for 24h, extracted with acetone Soxhlet for 48h, and dried at 65℃ for 4h to obtain a porous adsorption material. The porous adsorption material has an adsorption capacity of 91.22mg / g for heavy metal Pb2+, 105.31mg / g for cationic dye methylene blue, and 187.59mg / g for anionic dye acid fuchsin.

[0034] Example 2

[0035] The olive pomace was crushed through a 600-mesh sieve, 8 g of olive pomace powder was dispersed in 30 mL of water, and evenly dispersed under stirring at 500 rpm; 22 g of styrene, 23 g of acrylonitrile, 4 mL of cyclohexane, 8 g of triallyl isofluorate and 5 g of benzoyl peroxide were added, and an emulsion was formed under stirring at 500 rpm; after polymerization at 90 ° C for 4 h, acetone Soxhlet extraction was performed for 12 h, and drying was performed at 105 ° C for 4 h to obtain a porous adsorption material. The porous adsorption material has an adsorption capacity of 66.76 mg / g for heavy metal Pb2+, 106.63 mg / g for cationic dye methylene blue, and 297.33 mg / g for anionic dye acid fuchsin.

[0036] Example 3

[0037] The olive pomace was crushed through a 400-mesh sieve; 3g of olive pomace was dispersed in 25mL of water and stirred at 500rpm to disperse uniformly; 10g of 3-(dimethylamino)ethyl acrylate, 22g of acrylic acid, 3g of azobisisobutylnitrile and 4g of trimethylolpropane trimethacrylate were added, and 33mL of n-hexane was added under stirring at 500rpm to form an emulsion, and then polymerized at 80℃ for 8h, extracted with acetone Soxhlet for 24h, and dried at 105℃ for 4h to obtain a porous adsorption material. The porous adsorption material has an adsorption capacity of 200.19mg / g for heavy metal Pb2+, 95.17mg / g for cationic dye methylene blue, and 287.45mg / g for anionic dye acid fuchsin.

[0038] Example 4

[0039] The olive pomace was crushed through a 200-mesh sieve; 5 g of olive pomace was dispersed in 20 mL of water and stirred at 500 rpm to disperse uniformly; 15 g of dimethylaminoethyl methacrylate, 15 g of 2-acrylamido-2-methylpropanesulfonic acid, 5 g of ammonium persulfate and 5 g of N,N'-methylenebisacrylamide were added, and 35 mL of soybean oil was added under stirring at 500 rpm to form an emulsion, and then polymerized at 60 ° C for 24 h, extracted with acetone Soxhlet for 48 h, and dried at 105 ° C for 4 h to obtain a porous adsorption material. The adsorption amount of the adsorption material for heavy metal Pb2+ is 126.23 mg / g, the adsorption amount for cationic dye methylene blue is 144.25 mg / g, and the adsorption amount for anionic dye acid fuchsin is 223.21 mg / g, respectively.

[0040] Example 5

[0041] The olive pomace was crushed through a 300-mesh sieve; 6.5 g of olive pomace was dispersed in 25 mL of water, and the mixture was stirred and dispersed evenly at 500 rpm; 10 g of butyl acrylate, 25.5 g of allyl thiourea, 3.0 g of azobisisoheptanitrile and 5 g of trimethylolpropane triacrylate were added, and 25 mL of n-octane was added under stirring at 500 rpm to form an emulsion, and the mixture was polymerized at 80 °C for 4 h, and then extracted with acetone Soxhlet for 24 h, and dried at 105 °C for 4 h to obtain a porous adsorption material. The porous adsorption material has an adsorption capacity of 66.15 mg / g for heavy metal Pb2+, 122.55 mg / g for cationic dye methylene blue, and 127.82 mg / g for anionic dye acid fuchsin.

[0042] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a porous adsorption material using a Pickering emulsion stabilized by olive pomace as a template, characterized in that: The steps include: The olive pomace was crushed through a 600-mesh sieve, 8 g of olive pomace powder was dispersed in 30 mL of water, and dispersed evenly under stirring at 500 rpm; 22 g of styrene, 23 g of acrylonitrile, 4 mL of cyclohexane, 8 g of triallyl isocyanate and 5 g of benzoyl peroxide were added, and an emulsion was formed under stirring at 500 rpm; after polymerization at 90° C. for 4 h, the mixture was extracted with acetone Soxhlet for 12 h, and dried at 105° C. for 4 h to obtain a porous adsorption material.

Images