CN-122007136-A - Gradient oxygen release material with multilayer core-shell structure and preparation method and application thereof

CN122007136ACN 122007136 ACN122007136 ACN 122007136ACN-122007136-A

Abstract

The invention provides a multilayer core-shell structure gradient oxygen release material, a preparation method and application thereof, wherein the gradient oxygen release material comprises an inner core, an oxygen release functional shell layer and a permeation regulation layer from inside to outside; the core is quartz sand, the oxygen release functional shell layer is powder material wrapped outside the core, the powder material comprises calcium peroxide and sodium percarbonate, the permeation regulating layer is a paraffin film oxygen release material, and the paraffin film oxygen release material has obvious gradient oxygen release characteristics of early quick oxygen release, medium-term stable oxygen supply and later slow attenuation in water through the design of a multi-layer core-shell structure, so that the gradient and continuous release of oxygen are realized, the stability and the oxygen utilization rate of the oxygen release material are improved, the dissolved oxygen level of a water body can be effectively maintained, and the restoration requirements of different scenes of a groundwater source are adapted.

Inventors

LI YILUN
GUO LIN
LIU SHASHA
MA XIAOYU
ZHANG JUNZHENG
FENG CHEN
PAN FUJUN
FENG MENGYUAN

Assignees

河南省地质研究院

Dates

Publication Date: 20260512
Application Date: 20260415

Claims (10)

1. The gradient oxygen release material with the multilayer core-shell structure is characterized by comprising an inner core, an oxygen release functional shell layer and a permeation regulating layer from inside to outside; the inner core is quartz sand, the oxygen release functional shell layer is powder wrapped outside the inner core, the powder comprises calcium peroxide and sodium percarbonate, and the permeation regulating layer is a paraffin film.
2. The gradient oxygen release material with the multilayer core-shell structure according to claim 1, wherein the oxygen release functional shell layer further comprises bentonite and calcium carbonate, and the weight ratio of the calcium peroxide to the sodium percarbonate to the bentonite to the calcium carbonate is 8-12:3-5:3-5:1-3.
3. The gradient oxygen-releasing material of claim 2, wherein the weight ratio of calcium peroxide, sodium percarbonate, bentonite and calcium carbonate is 10:4:4:2.
4. The gradient oxygen release material with the multilayer core-shell structure according to claim 1, wherein the particle size of quartz sand is 0.5-1mm, the particle size of the coated oxygen release functional shell layer is 1.5-3mm, and the particle size of the coated permeation regulating layer is 2-3.5mm.
5. A method for preparing a gradient oxygen release material with a multilayer core-shell structure, which is characterized by comprising the following steps of: step S1, screening quartz sand, flushing the quartz sand with deionized water for multiple times after screening, and drying the quartz sand for later use; Step S2, spreading quartz sand in a rotating disc which is obliquely arranged for roll coating, uniformly spraying a polyvinyl alcohol solution on the quartz sand through spraying equipment, uniformly scattering mixed powder of an oxygen release functional shell layer on the surface of the quartz sand, and rotating the rotating disc to roll the quartz sand to form particles; Step S3, repeating the working procedure of the step S2 for 4-6 times until the shell powder with the oxygen release function is completely coated; s4, drying the particles coated by the roll coating, turning over at least once in the drying process, and scattering the particles; S5, after the particles are cooled to room temperature, sieving by a sieving device with the diameter of 1.5mm and 3mm, and collecting the particles with the diameter of 1.5-3.0 mm; and S6, melting paraffin, loading the particles collected in the step S5 on a metal net ladle, immersing the metal net ladle in the melted paraffin, lifting the metal net ladle, and cooling to form a paraffin film outside the particles.
6. The method for preparing a gradient oxygen-releasing material with a multilayer core-shell structure according to claim 5, wherein in step S5, particles with a particle size of <1.5mm are added into a rotating disc for secondary roll coating.
7. The preparation method of the gradient oxygen release material with the multilayer core-shell structure, which is characterized in that the loading thickness of particles in a metal net ladle is less than or equal to 1cm, the immersion time of the particles in paraffin is 2-3 seconds, and the particles stay above the molten paraffin for 10-15 seconds after the metal net ladle is lifted.
8. The preparation method of the multilayer core-shell structure gradient oxygen release material according to claim 5, wherein the particles are cooled by a cooling disc, stirring is carried out by a glass stirring device in the cooling process, paraffin is naturally cooled to solidify at room temperature, and the agglomerated particles are removed by sieving to obtain the gradient oxygen release material.
9. The application of the gradient oxygen release material with the multilayer core-shell structure in repairing a groundwater source by the gradient oxygen release material according to any one of claims 1 to 4 is characterized in that an in-situ injection method is adopted to perform prevention and control repair on a pollution source.
10. The application of the gradient oxygen release material with the multilayer core-shell structure in repairing a groundwater source by the gradient oxygen release material according to any one of claims 1 to 4 is characterized in that an in-situ oxidant injection method is adopted to repair and treat a polluted receptor.

Description

Gradient oxygen release material with multilayer core-shell structure and preparation method and application thereof Technical Field The invention belongs to the technical field of groundwater treatment, and particularly relates to a multilayer core-shell structure gradient oxygen release material, and a preparation method and application thereof. Background In recent years, a slow release technology has attracted a great deal of attention in the field of groundwater environment restoration. The application of the slow-release material can overcome the phenomena of tail support and rebound in the repairing process caused by the defects of short effect time of an oxidant, low utilization rate and the like in the traditional ISCO technology, so that the slow-release technology has great application potential in the aspect of in-situ groundwater repairing. The slow release material can bear various active components, including microbial clusters, matrixes, oxidants, oxygen release materials and the like, and can select proper active components for treatment aiming at different pollution sites. The slow-release material technology has low application cost and long acting time, and has good treatment effect on refractory organic pollutants, so that the slow-release material technology has wide application prospect in groundwater repair engineering. However, the existing groundwater slow-release technology is mostly used for repairing organic pollution, and aims at solving the problems that the existing slow-release material with exceeding iron and manganese in groundwater has complex manufacturing flow, high cost, easy secondary pollution and the like. Accordingly, there is a need to provide an improved solution to the above-mentioned deficiencies of the prior art. Disclosure of Invention The invention aims to overcome the defects in the prior art, and provides a multilayer core-shell structure gradient oxygen release material, and a preparation method and application thereof. In order to achieve the above object, the present invention provides the following technical solutions: The gradient oxygen release material comprises an inner core, an oxygen release functional shell layer and a permeation regulating layer from inside to outside; the inner core is quartz sand, the oxygen release functional shell layer is powder wrapped outside the inner core, the powder comprises calcium peroxide and sodium percarbonate, and the permeation regulating layer is a paraffin film. Preferably, the oxygen-releasing functional shell layer also comprises bentonite and calcium carbonate, wherein the weight ratio of the calcium peroxide to the sodium percarbonate to the bentonite to the calcium carbonate is 8-12:3-5:3-5:1-3. Preferably, the weight ratio of the calcium peroxide to the sodium percarbonate to the bentonite to the calcium carbonate is 10:4:4:2. Preferably, the particle size of the quartz sand is 0.5-1mm, the particle size of the shell layer coated with the oxygen release function is 1.5-3mm, and the particle size of the coating permeation regulating layer is 2-3.5mm. The preparation method of the gradient oxygen release material with the multilayer core-shell structure is used for preparing any gradient oxygen release material and comprises the following steps: step S1, screening quartz sand, flushing the quartz sand with deionized water for multiple times after screening, and drying the quartz sand for later use; Step S2, spreading quartz sand in a rotating disc which is obliquely arranged for roll coating, uniformly spraying a polyvinyl alcohol solution on the quartz sand through spraying equipment, uniformly scattering mixed powder of an oxygen release functional shell layer on the surface of the quartz sand, and rotating the rotating disc to roll the quartz sand to form particles; Step S3, repeating the working procedure of the step S2 for 4-6 times until the shell powder with the oxygen release function is completely coated; s4, drying the particles coated by the roll coating, turning over at least once in the drying process, and scattering the particles; S5, after the particles are cooled to room temperature, sieving by a sieving device with the diameter of 1.5mm and 3mm, and collecting the particles with the diameter of 1.5-3.0 mm; and S6, melting paraffin, loading the particles collected in the step S5 on a metal net ladle, immersing the metal net ladle in the melted paraffin, lifting the metal net ladle, and cooling to form a paraffin film outside the particles. Preferably, in step S5, particles with a particle size of <1.5mm are added to a rotating disc for a secondary roll coating. Preferably, the loading thickness of the particles in the metal net ladle is less than or equal to 1cm, the immersion time of the particles in the paraffin is 2-3 seconds, and the particles stay above the molten paraffin for 10-15 seconds after the metal net ladle is lifted. Preferably, the particles are cooled by a cooling disc, s