Novel environment-friendly dust falling agent and application thereof

Abstract

The invention discloses a novel environment-friendly dust falling agent and application thereof, and belongs to the technical field of preparation of dust falling agents, the novel environment-friendly dust falling agent comprises, by mass, 0.2%-0.6% of aldehyde polysaccharide, 0.6%-0.8% of chitosan, 0.8%-1.2% of sodium glycerophosphate, 0.2%-1.0% of a water-retaining agent, 0.1%-0.5% of a surfactant and the balance water; the used raw materials are wide in source, low in price, environment-friendly and degradable, and have the advantages of being high in bonding capacity, good in water retention capacity and wetting effect, high in wind erosion resistance and the like; the dust-reducing agent is a two-component dust-reducing system based on a temperature-sensitive response mechanism, is in a low-viscosity state before spraying and at the beginning of spraying, and has better flowability, permeability and atomization effect, and after spraying, a cross-linked network is formed by an imine bond formed by a Schiff base reaction of a hydrogen bond, an aldehyde group and an amino group through electrostatic attraction, so that the viscosity of the dust-reducing agent is increased, and the dust-reducing effect is improved. Therefore, the dust falling effect is enhanced.

Description

Technical Field

[0001] The invention belongs to the technical field of dust suppressant preparation, and in particular relates to an environmentally friendly new dust suppressant and application thereof. Background Art

[0002] With the acceleration of industrialization and urbanization, dust pollution has become an environmental problem that needs to be solved urgently. Dust not only causes serious harm to human health and causes various respiratory diseases, but also affects air quality and damages the ecological environment. In particular, it faces multiple technical challenges in sensitive areas (near bridges, municipal buildings, traffic arteries, etc.). In industrial production, dust is also flammable and explosive, posing a major safety hazard. It will also accelerate equipment wear and affect its service life. Therefore, in many fields such as coal mining, construction, road transportation, ore processing, and port terminals, taking effective dust reduction measures has become an inevitable requirement.

[0003] At present, the commonly used dust suppression methods include water sprinkling and chemical dust suppression. Water sprinkling achieves dust suppression by wetting the dust surface and reducing dust. It has the advantages of simple operation and low price, so it is widely used. In the hot and dry summer environment, traditional water mist dust suppression technology faces a double dilemma: when the ambient temperature exceeds 35°C, the evaporation rate of atomized water is high, and the water loss rate exceeds 60% within 5 minutes after spraying. This rapid evaporation phenomenon causes the dust surface to be only temporarily wet, and the particles cannot be effectively condensed. Instead, the dust is secondary after the water evaporates. Chemical dust suppression has the advantages of significant dust suppression effect and water resource saving, and is the current mainstream direction of development. At present, the dust suppressants on the market can be mainly divided into several categories: inorganic salts, organic polymers and surfactants. Inorganic salt dust suppressants such as calcium chloride and magnesium chloride have the advantages of low cost and quick effect, but they are easy to crystallize and have strong corrosiveness to equipment; organic polymer dust suppressants such as polyacrylamide have the characteristics of good durability and environmental protection, but the cost is relatively high; surfactant dust suppressants have good permeability and are used in small amounts, but there is a problem of poor stability. Compared with water, organic polymer dust suppressants have a higher viscosity, which is beneficial to improve the adhesion and durability of the dust suppressant, but it will reduce its fluidity, permeability and atomization effect. Therefore, an appropriate viscosity value is crucial for the dust reduction effect. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the present invention provides a new environmentally friendly dust suppressant, which is suitable for dust suppression under high temperature conditions in summer. The dust suppressant is based on an interpenetrating structure cross-linked by imine bonds and hydrogen bonds. It has a lower viscosity at low temperatures, better fluidity and permeability, and enhances the thermal motion of molecular chains at high temperatures to form a cross-linked network to improve the adhesion and durability of the dust suppressant.

[0005] The technical solution for achieving the purpose of the present invention is as follows:

[0006] An environmentally friendly new dust suppressant, calculated by mass percentage, comprises 0.2% - 0.6% aldehyde-group polysaccharide, 0.6% - 0.8% chitosan, 0.8% - 1.2% sodium glycerophosphate, 0.2% - 1.0% water retention agent, 0.1% - 0.5% surfactant, and the balance is water;

[0007] The aldehyde-group polysaccharide has one or several of the molecular structures of Formula I, Formula II, and Formula III as follows:

[0008]

[0009] In Formula I, R is at least one of H, Na, K, and alkyl.

[0010] Preferably, the chitosan is at least one of hydroxypropyl chitosan, hydroxyethyl chitosan, and deacetylated chitin, and the deacetylation degree of the chitosan is not less than 70%.

[0011] Preferably, the water retention agent is one or several of sodium carboxymethyl cellulose and sodium alginate.

[0012] Preferably, the surfactant is one or several of cocamidopropyl betaine, 3-sulfopropyl tetradecyldimethyl betaine, sodium dioctyl sulfosuccinate, fatty alcohol polyoxyethylene ether, alkyl sulfonate, and alkyl glycoside.

[0013] Preferably, the molecular structure of Formula I is obtained by oxidizing hyaluronic acid with Dess-Martin oxidant; the molecular structure of Formula II is obtained by oxidizing pullulan with Dess-Martin oxidant.

[0014] Preferably, the preparation method of the molecular structure of Formula III is as follows:

[0015] 1) The amino group in chitosan reacts with the epoxy group of N,N-bis(2-hydroxyethyl)-N-(oxiranylmethyl)amine;

[0016] 2) The product obtained from the reaction is oxidized with Dess-Martin oxidant to obtain the molecular structure of Formula III.

[0017] The present invention also discloses the using method of the environmentally friendly new dust suppressant: Mix the aldehyde-group polysaccharide, sodium glycerophosphate, and water to form Component A, mix the chitosan, water retention agent, surfactant, and water to form Component B, and spray using a two-component spraying device.

[0018] Preferably, the two-component spraying device includes a driving motor, an A-component feeding pipe, a B-component feeding pipe, and an atomizing disc; the A-component feeding pipe and the B-component feeding pipe are respectively connected to the atomizing disc, and the A-component and the B-component can be simultaneously input into the atomizing disc through the A-component feeding pipe and the B-component feeding pipe respectively.

[0019] The present invention also protects the application of the above-mentioned environmentally friendly new dust suppressant in complex geological construction, coal mining, building construction, road transportation, and ore processing.

[0020] Beneficial effects

[0021] The present invention includes the following beneficial effects: The present invention provides an environmentally friendly new dust suppressant, which uses raw materials with wide sources, low prices, environmental protection and degradability, and has the advantages of strong bonding ability, good water retention performance and wetting effect, and good anti-wind erosion effect; Based on the thermosensitive response mechanism of the two-component dust suppression system, the viscosity is low before spraying and at the beginning after spraying, and it has good fluidity, permeability and atomization effect. After spraying, through electrostatic attraction, hydrogen bonds and imine bonds formed by the reaction of aldehyde groups and amino groups through Schiff base reaction, a cross-linked network is formed, increasing its viscosity, thereby enhancing the dust suppression effect. Description of the drawings

[0022] Figure 1 It is a schematic diagram of the synthesis route of aldehyde group-containing polysaccharide of the present invention;

[0023] Figure 2 It is the cross-linking mechanism of the environmentally friendly new dust suppressant of the present invention. Specific embodiments

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

[0025] In the embodiments, the experimental methods used are all conventional methods unless otherwise specified, and the materials, reagents, etc. used can be obtained from commercial channels unless otherwise specified.

[0026] Now, the raw materials and equipment used in the examples and comparative examples are described as follows:

[0027] Hyaluronic acid: average molecular weight 10,000, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0028] Pullulan polysaccharide: average molecular weight 20,000, purchased from Shanghai Haohong Biopharmaceutical Technology Co., Ltd.;

[0029] Chitosan: Hydroxymethyl chitosan, degree of deacetylation ≥ 95% (viscosity 50-100 mPa.s), purchased from Shanghai Yien Chemical Technology;

[0030] Sodium glycerophosphate: purchased from Shanghai Dingfen Chemical Technology;

[0031] Water-retaining agent: sodium carboxymethyl cellulose, average molecular weight 90,000, (viscosity 50-100 mPa·s), purchased from Aike Reagents;

[0032] Surfactant: cocamidopropyl betaine, Guangdong Wengjiang Chemical Reagent;

[0033] Dess-Martin oxidant: purchased from Shanghai Yien Chemical Technology;

[0034] Diethanolamine: purchased from Aiko Reagents;

[0035] Epichlorohydrin: purchased from Shanghai MacLean Biochemical Technology Co., Ltd.;

[0036] N,N-bis(2-hydroxyethyl)-N-(oxiranylmethyl)amine (self-made): obtained by the reaction of diethanolamine and epichlorohydrin.

[0037] Aldehyde polysaccharide 1

[0038] 2.0 g of hyaluronic acid was dissolved in 100 mL of DMSO, 4.0 g of Dess-Martin periodinane was slowly added to the solution, and the reaction was carried out at 30° C. in the dark for 24 h. The reaction solution was diluted with deionized water, and a saturated sodium carbonate solution was added to terminate the reaction. The solid was removed after centrifugation, and a mixed solution of ethanol and acetone was added to the obtained solution. The precipitated solid was added into a flask, washed with a mixed solution of ethanol and acetone three times, and freeze-dried to obtain the formaldehyde polysaccharide 1.

[0039] Aldehyde polysaccharide 2

[0040] Take 2.0 g of pullulan and dissolve it in 100 mL of DMSO. Slowly add 4.0 g of Dess-Martin periodinane to the solution, react at 30°C in the dark for 24 hours, dilute the reaction solution with deionized water, add saturated sodium carbonate solution to terminate the reaction, remove the solid after centrifugation, add a mixed solution of ethanol and acetone to the resulting solution, add the precipitated solid into the flask, wash it three times with a mixed solution of ethanol and acetone, and freeze-dry to obtain the formaldehyde polysaccharide 2.

[0041] Aldehyde polysaccharide 3

[0042] 1) Add 3.0 g of chitosan and 8 g of 1-allyl-3-methylimidazolium chloride ionic liquid into a three-necked flask, heat and stir at 80 °C until the chitosan is completely dissolved. Add 4.5 g of N,N-bis(2-hydroxyethyl)-N-(oxiranylmethyl)amine into the flask and stir at 75 °C for 6 h. Then add a mixed solution of ethanol and acetone into the flask to precipitate a solid. Filter the mixed solution to obtain the solid, wash it 3 times with the mixed solution of ethanol and acetone to remove 1-allyl-3-methylimidazolium chloride and N,N-bis(2-hydroxyethyl)-N-(oxiranylmethyl)amine, and dry it to obtain modified chitosan;

[0043] 2) Dissolve 2.0 g of modified chitosan in 100 mL of DMSO, slowly add 4.0 g of Dess-Martin oxidant to the solution, react in the dark at 30 °C for 24 h, dilute the reaction solution with deionized water, add saturated sodium carbonate solution to terminate the reaction, remove the solid by centrifugation, add a mixed solution of ethanol and acetone to the obtained solution, add it into the flask to precipitate a solid, wash it 3 times with the mixed solution of ethanol and acetone, and freeze-dry to obtain aldehyde-functionalized polysaccharide 3.

[0044] Usage method of an environmentally friendly new dust suppressant

[0045] Mix aldehyde-functionalized polysaccharide, sodium glycerophosphate and water to form component A, and mix chitosan, water-retaining agent, surfactant and water to form component B. The water in component A and component B is of equal volume, and a two-component spraying device is used for spraying.

[0046] Table 1 Formulation of environmentally friendly new dust suppressant (unit / g)

[0047]

[0048] The following are the test methods for the performance parameters involved in the present invention:

[0049] (1) Surface tension: At 20 °C, use an automatic interfacial tension instrument and measure it by the ring method;

[0050] (2) Viscosity: Measure it according to the standard "ASTM D445-2024". After preparing the dust suppressant, conduct the first measurement at 25 °C, and then place the dust suppressant at 30 °C, 35 °C, and 40 °C for 60 s, 200 s, and 400 s respectively, and then conduct the measurement;

[0051] (3) Wind erosion resistance experiment: Prepare several glass plates of 20 cm * 20 cm, let 20 g of dry dust naturally fall on the glass plates to form dust piles, and then spray the dust suppressant solution on the dust piles to make the surface of the dust wet. Put the treated dust samples into an oven at 60 °C and dry for 6 h, then take them out and weigh the dust weight M0 at this time. Place the dust piles in front of a blower and blow them for 30 min, and measure the remaining mass Mx , the mass loss rate of the dust pile is calculated by formula (1), and the wind speed is set at 16 m / s.

[0052]

[0053] (4) Water retention performance: Sprinkle the dust suppressant solution on the dust pile respectively, weigh the mass as M1, place the sample in an oven at 60 °C and dry it for 2 h, then weigh the mass as M2, and calculate the water content determination by formula (2).

[0054]

[0055] Table 2 Physical properties of the environmentally friendly new dust suppressant

[0056]

[0057] From the data of Examples 1 to 5 in Table 2, it can be seen that the environmentally friendly new dust suppressant prepared by the present invention has a lower surface tension, a lower viscosity in the initial stage, and good fluidity, permeability and wetting ability. From the data of Examples 1 to 3, it can be seen that as the content of aldehyde-modified polysaccharide increases, the initial viscosity increases, and the increase in viscosity with time also increases significantly. From the data of Examples 1, 4 and 5, it can be seen that at 30 °C, the viscosity of aldehyde-modified polysaccharide 3 increases more significantly, followed by aldehyde-modified polysaccharide 2, and aldehyde-modified polysaccharide 1 is the worst. The aldehyde content in aldehyde-modified polysaccharide 1 is the lowest, and it is on the ring with a large position and low reactivity; the aldehyde content in aldehyde-modified polysaccharide 3 is the highest, and two of the aldehydes are outside the ring with a small steric hindrance and good reactivity even at a lower temperature. From the data of Comparative Example 2, it can be seen that when unmodified pullulan polysaccharide is added, the viscosity only increases slightly at a temperature of 40 °C. Therefore, dust suppressants applicable to different temperature ranges can be prepared by adjusting the content and type of aldehyde-modified polysaccharide.

[0058] Table 3 Determination of the dust suppression performance of the environmentally friendly new dust suppressant

[0059]

[0060] From the data in Table 3, it can be seen that the environmentally friendly new dust suppressant prepared by the present invention has good anti-wind erosion ability and water retention rate, and can effectively suppress dust. As the water is lost, the concentrations of aldehyde-modified polysaccharide, chitosan and sodium glycerophosphate gradually increase, and the crosslinking density gradually increases, forming a hydrogel film. Within a certain range, the more the water is lost, the better its water retention ability and the better its anti-wind erosion ability; from the data of Examples 1 to 3, it can be seen that the water retention rate and anti-wind erosion ability increase with the increase of aldehyde-modified polysaccharide, which is due to the increase of crosslinking density.

[0061] As can be seen from the above, the environmentally friendly new dust suppressant prepared by the present invention is very suitable for high-temperature environments and also has good performance in normal-temperature environments.

[0062] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. An environmentally friendly new dust suppressant, characterized in that, By mass percentage, it includes 0.2% - 0.6% aldehyde group-containing polysaccharide, 0.6% - 0.8% chitosan, 0.8% - 1.2% sodium glycerophosphate, 0.2% - 1.0% water retaining agent, 0.1% - 0.5% surfactant, and the balance is water; The aldehyde group-containing polysaccharide has one or more of the molecular structures of Formula I, Formula II and Formula III as follows: In Formula I, R is at least one of H, Na, K, and alkyl.

2. The environmentally friendly and new dust suppressant according to claim 1, characterized in that The chitosan is at least one of hydroxypropyl chitosan, hydroxyethyl chitosan and deacetylated chitin, and the deacetylation degree of the chitosan is not less than 70%.

3. An environmentally friendly new dust suppressant as claimed in claim 1, characterized in that, The water retaining agent is one or more of sodium carboxymethyl cellulose and sodium alginate.

4. The environmentally friendly new dust suppressant according to claim 1, characterized in that, The surfactant is one or more of coconut oil amide propyl betaine, 3-sulfopropyl tetradecyl dimethyl betaine, dioctyl sulfosuccinate, fatty alcohol polyoxyethylene ether, alkyl sulfonate and alkyl glycoside.

5. The environmentally friendly new dust suppressant according to claim 1, characterized in that, The molecular structure of Formula I is obtained by oxidizing hyaluronic acid with Dess-Martin oxidant; the molecular structure of Formula II is obtained by oxidizing pullulan with Dess-Martin oxidant.

6. The environmentally friendly and novel dust suppressant according to claim 1, wherein The preparation method of the molecular structure of Formula III is as follows: 1) The amino group in chitosan reacts with the epoxy group of N,N-bis(2-hydroxyethyl)-N-(oxiranylmethyl)amine; 2) The reaction product is oxidized with Dess-Martin oxidant to obtain the molecular structure of Formula III.

7. An environmentally friendly new dust suppressant according to any one of claims 1 to 6, characterized in that, The using method of the environment-friendly new dust suppressant: Mix the aldehyde group-containing polysaccharide, sodium glycerophosphate and water as Component A, mix the chitosan, water retaining agent, surfactant and water as Component B, and spray them using a two-component spraying device.

8. The environmentally friendly new dust suppressant according to claim 7, characterized in that, The two-component spraying device includes a driving motor, an A-component feeding pipe, a B-component feeding pipe and an atomizing disc; the A-component feeding pipe and the B-component feeding pipe are respectively connected to the atomizing disc, and Component A and Component B can be simultaneously input into the atomizing disc through the A-component feeding pipe and the B-component feeding pipe respectively.

9. The application of an environment-friendly new dust suppressant according to any one of claims 1 - 6 in dust suppression during complex geological construction, coal mining, building construction, road transportation and ore processing.

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