Alginate-base organic-inorganic composite hydrogel filtering membrane and preparation method thereof

Abstract

The invention discloses an alginate-base organic-inorganic composite hydrogel filtering membrane, which is designed and prepared aiming at the problems of low mechanical strength, high probability of deformation, low flux and the like of a pure ionic cross-linked hydrogel filtering membrane. According to the filtering membrane, sodium alginate is used as a membrane forming substrate, micro-nano inorganic particles are used as a reinforcing agent and a pore-enlarging agent, and the composite hydrogel membrane which is obtained after cross-linking of a cross-linking agent and elution of a pore-forming agent has better stability and mechanical performance than the pure ionic cross-linked alginate hydrogel membrane. The mechanical strength and the pore size of the membrane are adjusted by changing the type, the particle diameter size and the added amount of the micro-nano inorganic particles and the type and the concentration of the ionic cross-linking agent. The composite hydrogel filtering membrane is prepared through a simple preparation process and is low in cost; no organic waste liquid is produced; the obtained hydrogel flat membrane can resist the pressure of 0.1-0.6 MPa; the alginate hydrogel is dissolved after being subjected to soaking treatment of a sodium citrate solution; expensive micro-nano inorganic particles can be recovered through simple precipitation separation.

Description

technical field

[0001] The invention relates to an alginate-based organic-inorganic composite hydrogel filtration membrane and a preparation method thereof, belonging to the field of environmental functional materials and membranes. Background technique

[0002] Due to its own hydrophobicity, traditional membrane filtration materials can easily cause irreversible deposition of macromolecules, colloids, electrolytes, etc. on the membrane surface or in the membrane, resulting in membrane fouling and a continuous decrease in the flux of the membrane, so that the membrane separation process cannot be carried out normally. In view of the fact that the surface of the polymer membrane is easy to adsorb hydrophobic substances such as proteins, an effective way to reduce membrane fouling is to improve the surface properties of the membrane, such as charging the membrane surface or hydrophilizing the hydrophobic membrane.

[0003] Blending modification is a simple method to improve me...