Preparation method and application of mixed substrate membrane with laminar and cage-shaped synergetic sieving effect

Abstract

The invention discloses a preparation method and application of a mixed substrate membrane with a laminar and cage-shaped synergetic sieving effect. The preparation method is characterized in that firstly, a zeolite imidazole framework ester material ZIF-8 is introduced into g-C3N4 (graphitized carbonitride) dispersion liquid in site; then, a composite material is dispersed into a polyether blockamide copolymer; a polyether block amide gas separation membrane with the laminar and cage-shaped synergetic sieving effect is prepared by a solution tape casting method; the prepared membrane is a homogeneous dense membrane; the wet membrane thickness is controlled to be 50 to 500mum. The provided inorganic material preparation process is easy to control; holes in tri-s-triazine rings of g-C3N4 and between nanosheet layers of a g-C3N4 and ZIF-8 composite material provide passages for CO2; the prepared membrane has acid and alkali resistance and good flexibility; when the membrane is used forgas separation, the excellent comprehensive performance is realized; the CO2 can be effectively and selectively separated; a fast migration passage is provided for CO2 transfer.

Description

technical field

[0001] The invention relates to a preparation method and application of a mixed matrix membrane with sheet-layer and cage-like synergistic screening functions, and belongs to the technical field of gas separation membranes. Background technique

[0002] Mixed matrix membrane is a composite membrane in which inorganic materials are added to organic polymers. Due to its excellent separation performance, simple preparation, economical and practical, it has become a research hotspot for current researchers. The introduction of inorganic particles in the mixed matrix membrane on the one hand interrupts the accumulation of molecular chains, speeds up the transfer of gas molecules, and improves the gas permeability. On the other hand, inorganic particles can not only increase the affinity for the target gas, but also provide diffusion channels that match the molecular dynamic diameter of the target gas, thereby enhancing the gas selectivity. Therefore, mixed matrix...