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CN-122011447-A - Black soldier fly chitosan-based catalytic functional film and preparation method and application thereof

CN122011447ACN 122011447 ACN122011447 ACN 122011447ACN-122011447-A

Abstract

The invention relates to the technical field of functional film materials and green chemical industry, in particular to a hermetia illucens chitosan-based catalytic functional film, and a preparation method and application thereof. The method comprises the steps of carrying out quaternization modification on hermetia illucens chitosan, loading layered double hydroxide or nano solid base catalytic active components into the quaternized chitosan through an in-situ hydrothermal growth method or a physical blending method, and finally, carrying out tape casting film forming and crosslinking curing to obtain the catalytic functional film with the three-dimensional network structure. The invention takes the renewable hermetia illucens chitosan as a matrix, and realizes the firm anchoring of the catalyst and the matrix on the molecular/nano scale and the optimization of the mass transfer channel through the synergistic strategy of 'functional matrix design-in-situ structure symbiotic construction-crosslinked network reinforcement'. The obtained membrane has excellent anion conductivity, catalytic activity, mechanical strength and operation stability, and can be directly used as a core component of a membrane reactor for continuously and efficiently preparing biodiesel.

Inventors

  • DUAN XIAOLING
  • Qi Xingang
  • OuYang Zixuan
  • Huai Chengwan
  • CHEN JIAYAO

Assignees

  • 湖北第二师范学院

Dates

Publication Date
20260512
Application Date
20260127

Claims (10)

  1. 1. The preparation method of the hermetia illucens chitosan-based catalytic functional membrane is characterized by comprising the following steps of: s1, performing quaternization modification on hermetia illucens chitosan to obtain quaternized chitosan; s2, loading a catalytic active component into the quaternized chitosan to obtain a catalyst-loaded compound, wherein the catalytic active component is layered double hydroxide or nano solid base catalyst; And S3, forming the composite into a film, and performing crosslinking curing to obtain the catalytic functional film.
  2. 2. The preparation method according to claim 1, wherein the layered double hydroxide comprises ZnCo-LDH, and the layered double hydroxide is supported in the quaternized chitosan by in-situ hydrothermal growth.
  3. 3. The preparation method according to claim 1, wherein the nano-solid base catalyst is at least one selected from nano CaO, nano MgO, or nano SrO, and the nano-solid base catalyst is supported in the quaternized chitosan by a physical blending method.
  4. 4. The method of claim 2, wherein the in situ hydrothermal growth process comprises: S2-1, dissolving zinc salt, cobalt salt and urea in water to form a precursor solution; S2-2, dissolving the quaternized chitosan obtained in the step S1, and mixing with the precursor solution; s2-3, carrying out hydrothermal reaction on the mixed solution.
  5. 5. The preparation method according to claim 4, wherein the molar ratio of Zn 2+ in the zinc salt to Co 2+ in the cobalt salt is (0.5-3) 1, and the mass ratio of the total mass of the quaternized chitosan, the zinc salt and the cobalt salt to the urea is (1) (2-3) 1.6-2.4.
  6. 6. The method according to claim 4, wherein the hydrothermal reaction is carried out at a temperature of 120 to 180 ℃ for a time of 6 to 24 hours.
  7. 7. The preparation method according to claim 3, wherein the nano solid base catalyst is used in an amount of 10% -60% of the mass of the quaternized chitosan.
  8. 8. The method according to claim 1, wherein in the step S1, the quaternizing agent used for the quaternization modification is at least one member selected from the group consisting of 2, 3-epoxypropyltrimethylammonium chloride and chloroacetamide, and the molar ratio of the quaternizing agent to the chitosan structural unit is (1-3): 1.
  9. 9. A hermetia illucens chitosan-based catalytic functional film obtained by the preparation method according to any one of claims 1-8.
  10. 10. Use of the hermetia illucens chitosan-based catalytic functional membrane according to claim 9 for preparing biodiesel, wherein the raw oil used for preparing the biodiesel comprises free fatty acids and triglycerides.

Description

Black soldier fly chitosan-based catalytic functional film and preparation method and application thereof Technical Field The invention relates to the technical field of functional film materials and green chemical industry, in particular to a hermetia illucens chitosan-based catalytic functional film, and a preparation method and application thereof. Background Biodiesel, which is a green renewable liquid fuel, is critical for achieving the "two carbon" goal in its large-scale production. Currently, catalytic membrane reactors coupled with heterogeneous catalysis and membrane separation technologies offer great potential. However, the core catalytic functional membrane faces a series of bottlenecks in the combination mode of the catalyst and the carrier in the process of industrialization in laboratories. For example, in the prior art, the catalyst is loaded on the polymer membrane through single physical blending or impregnation, and the catalyst is easy to leach and fall off in fluid shearing, heat and chemical environments running for a long time due to weak interaction, so that the catalytic activity is attenuated, products are polluted, the advantages of heterogeneous catalysis and easy separation are lost, and crosslinking modification cannot be fundamentally solved. Secondly, catalyst loading is required to be increased to improve efficiency, but high loading is easy to cause membrane densification and mass transfer channel blockage, so that contradiction between high loading and low utilization is formed; and the traditional polymer carrier only plays a mechanical supporting role, further exacerbating mass transfer limitation. In addition, the existing catalytic film has single function, the acidic film only can catalyze the esterification of free fatty acid and has low efficiency on triglyceride, the alkaline film or the solid base catalyst has good transesterification, but is easy to be saponified and deactivated by the free fatty acid in the raw materials, and the complex pretreatment is needed to increase the process cost in the face of the actual waste grease raw materials containing two types of components. For example, according to the response surface method optimization HTCC/Na 2SiO3/ECH hybrid membrane, epichlorohydrin is used as a connecting agent, sodium silicate is chemically fixed on a chitosan quaternary ammonium salt molecular chain to prepare the sodium silicate/chitosan quaternary ammonium salt organic-inorganic hybrid membrane, but the sodium silicate has leaching risk, covalent bonds can be broken in long-term use, and the patent CN117339630A discloses a solid phase preparation of a sulfonated chitosan membrane, which can only catalyze esterification, and the acidity nature of the sulfonated chitosan membrane limits the application of the sulfonated chitosan membrane in transesterification. Therefore, there is a need to develop a catalytic functional membrane that systematically solves the above-mentioned dilemma from the combined mode, structural design and functional integration level, and has a milestone significance for promoting the green and continuous process of biodiesel production. Disclosure of Invention In view of the above, the invention provides a hermetia illucens chitosan-based catalytic functional film, and a preparation method and application thereof. The invention aims to realize firm and uniform loading of catalytic active components in a membrane matrix through innovation of material design and preparation process, construct a through microstructure favorable for substance transmission, endow the membrane with the capability of synergetically catalyzing various reactions, and solve the technical problems of poor stability, low mass transfer efficiency due to compact structure and limited raw material adaptability due to single function of the existing catalytic functional membrane caused by unstable combination of a catalyst and a carrier. The technical scheme of the invention is realized as follows: In a first aspect, the invention provides a preparation method of a hermetia illucens chitosan-based catalytic functional film, which comprises the following steps: s1, performing quaternization modification on hermetia illucens chitosan to obtain quaternized chitosan; s2, loading a catalytic active component into the quaternized chitosan to obtain a catalyst-loaded compound, wherein the catalytic active component is layered double hydroxide or nano solid base catalyst; And S3, forming the composite into a film, and performing crosslinking curing to obtain the catalytic functional film. Preferably, the layered double hydroxide comprises ZnCo-LDH, which is supported in the quaternized chitosan by in situ hydrothermal growth. Specifically, the ZnCo-LDH has the advantages of acid-base synergistic catalytic capability, good compatibility with chitosan matrix, high structural stability and controllable cost. Preferably, the nano solid base catalyst is selected from at