CN-121991406-A - Preparation method of cellulose full-biology base aerogel based on furfural residues

CN121991406ACN 121991406 ACN121991406 ACN 121991406ACN-121991406-A

Abstract

The invention discloses a preparation method of cellulose full-biology base aerogel based on furfural residues, and belongs to the technical field of biomass materials. According to the method, furfural residue is used as a raw material, choline chloride-lactic acid eutectic solvent is adopted to separate for 8 hours under the conditions of 120 ℃ and a solid-liquid ratio of 1:30 to extract cellulose, a precursor is prepared according to a proportion of 0.2g of cellulose, 4g of 1.5wt% of chitosan mixed solution and 3g of 2.5wt% of PVA aqueous solution, and the hydrophobic modification is completed through 3 times of freezing-freeze thawing cycles and 24 hours of freeze drying aerogel and 3 times of palm wax dipping-drying cycles. The contact angle of the prepared aerogel water reaches 133.2 degrees, the oil absorption rate of the prepared aerogel water is up to 25.607g/g, the oil absorption capacity of the prepared aerogel water after 10 times of circulation is kept 96.46%, the prepared aerogel water has excellent compression resilience performance, can selectively adsorb an oil phase, is suitable for the treatment of oily wastewater, and realizes win-win utilization of furfural residue and environmental protection treatment.

Inventors

ZHU CHUNSHAN
ZHANG QIAOFEI
ZHANG BINPENG
SUN WANPENG
ZHAO MEIJING
GAO TINGTING
YANG YINGHUI
LI ZONGHAN

Assignees

河南工业大学

Dates

Publication Date: 20260508
Application Date: 20260130

Claims (7)

1. The preparation method of the cellulose all-bio-based aerogel based on the furfural residues is characterized by comprising the following steps of: Separating and extracting cellulose by using furfural residue as a raw material by adopting a eutectic solvent method, wherein the eutectic solvent is a choline chloride-lactic acid system, the molar ratio of choline chloride to lactic acid is 1:10, and the separation conditions are that the separation temperature is 120 ℃, the separation time is 8h, and the solid-liquid ratio is 1:30, so as to obtain the cellulose after extraction; Preparing 2.5wt% of polyvinyl alcohol (PVA) aqueous solution, dissolving chitosan in 1wt% of acetic acid and 1wt% of citric acid aqueous solution to prepare 1.5wt% of chitosan mixed solution, mixing according to the proportion of 0.2g of cellulose, 4g of 1.5wt% of chitosan mixed solution and 3g of 2.5wt% of PVA aqueous solution, and uniformly stirring to obtain aerogel precursor mixed solution; Step three, freezing-freeze thawing the precursor mixed solution obtained in the step two for 3 times, and then putting the precursor mixed solution into a freeze drying box for freeze drying for 24 hours to obtain furfural residue cellulose aerogel; And fourthly, adding the palm wax into ethyl acetate, continuously stirring at 60 ℃ until a transparent solution is formed, transferring into a water bath at 30 ℃ for heat preservation, immersing the cellulose aerogel prepared in the third step into the wax solution for 1 minute, taking out, drying in a vacuum oven at 60 ℃ for 1 hour, and repeating the immersion-drying cycle for 3 times to obtain the cellulose all-bio-based aerogel oil absorption material.
2. The preparation method of the eutectic solvent according to claim 1, wherein the preparation method of the eutectic solvent in the first step comprises the steps of mixing choline chloride and lactic acid in a molar ratio of 1:10 in a round-bottomed flask, heating and stirring at 60 ℃ for reaction for 1 hour until the mixture is in a uniform transparent state.
3. The method according to claim 1, wherein the step one of extracting cellulose further comprises a post-treatment step of filtering the mixture after the reaction, washing the residue with absolute ethanol, washing with deionized water, and drying at 105 ℃ for 4 hours to obtain refined cellulose.
4. The preparation method according to claim 1, wherein the specific conditions of the freezing-thawing cycle in the third step are that the thawing is carried out in a refrigerator and repeated 3 times, the freezing temperature is-18 ℃ to 25 ℃, the time of each freezing is not less than 4 hours, and the thawing mode is room temperature natural thawing.
5. The method according to claim 1, wherein the ratio of the amount of palm wax to ethyl acetate in the fourth step is 400 mg/50 mL.
6. The preparation method of claim 1, wherein in the second step, the stirring speed is 300-500 r/min, and the stirring time is 1-2 h, so that the uniformity and stability of the mixed solution are ensured.
7. The method according to claim 1, wherein the vacuum degree of freeze-drying in the third step is 1 to 10pa, and the freezing temperature is-50 ℃ to 60 ℃.

Description

Preparation method of cellulose full-biology base aerogel based on furfural residues Technical Field The invention relates to the technical field of biomass material preparation, in particular to a preparation method of cellulose full-biology base aerogel based on furfural residues. Background With the acceleration of industrialization progress, the discharge amount of oily wastewater produced in industries such as petroleum exploration, refining and machining is increased year by year, and meanwhile, the problem of oil spilling pollution caused by ship leakage, oil depot accidents and the like is also increasingly prominent. If the oily wastewater is directly discharged without effective treatment, the ecological balance of the water body can be seriously destroyed, soil and underground water are polluted, and finally the human health is endangered through a food chain. At present, the treatment method of the oily wastewater mainly comprises a physical method, a chemical method and a biological method, but has obvious defects that an oil separation tank in the physical method can only remove floating oil, the removal rate of the air floatation method on the emulsified oil is low, the energy consumption is high, the chemical method is easy to produce oily sludge or toxic intermediate products, the biological method has long treatment period, and the high-concentration oil can inhibit the microbial activity. The adsorption method is a preferable technology for advanced treatment of oily wastewater due to simple operation, environmental protection and no pollution, but the traditional adsorption material has various bottlenecks of high regeneration energy consumption of active carbon, rapid attenuation of adsorption capacity, nondegradable synthetic polymer material, easy secondary pollution, low porosity of natural material, poor mechanical strength and unstable oil absorption performance. Cellulose is taken as a natural polymer material with the most abundant reserves in the nature, has the advantages of being renewable, degradable, good in biocompatibility and the like, and is an ideal raw material for preparing the green oil absorption material. The aerogel is taken as an ultra-light solid material with a nano porous structure, has the characteristics of high porosity, large specific surface area and the like, and the cellulose aerogel prepared by combining cellulose and the aerogel has the advantages of the cellulose aerogel and the aerogel, and has great potential in the oil absorption field. However, natural cellulose contains a large amount of hydroxyl groups, the prepared cellulose-based aerogel is strong in hydrophilicity, cannot be directly used for oil-water separation and needs to be subjected to hydrophobic modification, and meanwhile, the cost and the source of the cellulose raw material limit the large-scale application of the cellulose-based aerogel. The furfural residue is a main byproduct of producing furfural by acid-catalyzed hydrolysis of agricultural and forestry wastes such as corncobs, the yield of China is huge every year, and the furfural residue is mostly treated in a stacking or burning mode at present, so that not only is the resource wasted, but also serious environmental problems are caused. The furfural residue is rich in lignocellulose components, the treatment cost is low, cellulose is extracted from the furfural residue for preparing aerogel, the recycling of the furfural residue can be realized, the production cost is reduced, the environmental pressure is reduced, and the sustainable development concept is met. Therefore, the development of the preparation method of the cellulose full-bio-based aerogel with the furfural residue as the raw material, simple process and excellent performance has important significance for solving the problem of oil pollution. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a preparation method of cellulose full-bio-based aerogel based on furfural residues, which is characterized in that the cellulose is extracted from the furfural residues as raw materials, and the full-bio-based aerogel oil-absorbing material with high oil absorption multiplying power, good circulation stability and excellent compression-resistant rebound performance is prepared by combining a sol-gel-freeze drying process and hydrophobic modification treatment, so that the dual purposes of high-value utilization of the furfural residues and oil-containing pollution treatment are realized. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows, and the preparation method of the cellulose full bio-based aerogel based on furfural residues comprises the following steps: extracting furfural residue cellulose, namely separating and extracting the cellulose by adopting a eutectic solvent method, wherein the eutectic solvent is a choline chloride-lactic acid system, the molar ratio of choline chlori