CN-115608162-B - GO/Al2O3Preparation method of composite ceramic ultrafiltration membrane

Abstract

The invention discloses a preparation method of a GO/Al 2 O 3 composite ceramic ultrafiltration membrane, which comprises the following steps of weighing graphene oxide, pouring the graphene oxide into a container, adding distilled water, stirring and dispersing on a constant-temperature water bath magnetic stirrer, then performing ultrasonic dispersion by using an ultrasonic dispersing instrument to obtain graphene oxide dispersion, weighing pseudo-boehmite, dissolving the pseudo-boehmite into the graphene oxide dispersion, placing the graphene oxide dispersion on the constant-temperature water bath magnetic stirrer for stirring and dispersing, then dripping calculated nitric acid by using a constant-pressure dropping funnel, continuously stirring and peptizing to obtain GO/AlOOH mixed sol, and weighing PVA solution with the mass of 1:1 and GO/AlOOH mixed sol, and stirring the PVA solution to obtain a coating liquid.

Inventors

• LI YANG
• LI JING
• WANG NING
• LI TAO
• LIN JIAYI
• CHEN QI
• XUE AN
• CHEN LU
• PEI XIANGLIN

Assignees

• 贵州师范大学

Dates

Publication Date

20260512

Application Date

20221110

Claims (7)

1. 1. The preparation method of the GO/Al 2 O 3 composite ceramic ultrafiltration membrane is characterized by comprising the following steps of: Weighing graphene oxide, pouring the graphene oxide into a container, adding distilled water, stirring and dispersing on a constant-temperature water bath magnetic stirrer, and then performing ultrasonic dispersion by using an ultrasonic dispersing instrument to obtain graphene oxide dispersion liquid; Weighing pseudo-boehmite, dissolving the pseudo-boehmite into graphene oxide dispersion liquid, placing the graphene oxide dispersion liquid on a constant-temperature water bath magnetic stirrer for stirring and dispersing, then dripping calculated nitric acid by using a constant-pressure dropping funnel, and continuing stirring and peptizing to obtain GO/AlOOH mixed sol; Step three, weighing PVA solution with the mass of 1:1 and GO/AlOOH mixed sol, and stirring the PVA solution and the GO/AlOOH mixed sol to obtain coating liquid; And fourthly, coating a film on the surface of the matrix by using an impregnation method, and drying and calcining at a high temperature to obtain the GO/Al 2 O 3 composite ceramic ultrafiltration membrane.
2. 2. The method for preparing the GO/Al 2 O 3 composite ceramic ultrafiltration membrane according to claim 1, wherein the mass ratio of pseudoboehmite to water in the second step is 1:10-1:20, and the molar ratio of nitric acid to pseudoboehmite is 1:5.
3. 3. The preparation method of the GO/Al 2 O 3 composite ceramic ultrafiltration membrane according to claim 1, wherein the heating and stirring temperature in the second step is 25 ℃, and the peptization time is 5-40 min.
4. 4. The method for preparing the GO/Al 2 O 3 composite ceramic ultrafiltration membrane according to claim 1, wherein PVA solution added into the film coating liquid in the third step is film forming agent, and the PVA concentration is 2% -4%.
5. 5. The method for preparing the GO/Al 2 O 3 composite ceramic ultrafiltration membrane according to claim 1, wherein the matrix material used for the coating in the fourth step is alumina, zirconia or silicon carbide porous ceramic or porous ceramic microfiltration membrane.
6. 6. The preparation method of the GO/Al 2 O 3 composite ceramic ultrafiltration membrane according to claim 1 is characterized in that the drying system of the composite ceramic ultrafiltration membrane in the fourth step is that the drying temperature of a blast drying oven is 60-80 ℃ and the drying time is 1-3 h.
7. 7. The method for preparing the GO/Al 2 O 3 composite ceramic ultrafiltration membrane according to claim 1, wherein in the fourth step, the calcination mechanism of the composite ceramic ultrafiltration membrane in a muffle furnace is that the calcination temperature is 400-600 ℃, the heating rate is 0.5-2 ℃ per minute, and the heat preservation time is 0.5-2 hours.

Description

Preparation method of GO/Al 2O3 composite ceramic ultrafiltration membrane Technical Field The invention relates to the technical field of preparation of composite ceramic ultrafiltration membranes, in particular to a preparation method of a GO/Al 2O3 composite ceramic ultrafiltration membrane. Background In recent years, due to the advantages of ultrathin thickness, excellent molecular sieving capability, high chemical stability, high mechanical strength and the like of a Graphene Oxide film (Graphene Oxide Membrane, GOM), the Graphene Oxide film has become a research hot spot in the field of film materials, the interlayer spacing of Graphene Oxide (GO) is about 0.35-0.45 nm, the interlayer spacing of the GOM formed by stacking GO sheets is 0.78-0.80 nm, the interlayer spacing can repel most molecules and ions freely through water molecules, the application prospect in the fields of nanofiltration and reverse osmosis is wide, a large number of hydrophilic oxygen-containing functional groups (carboxyl, hydroxyl, epoxy, carbonyl and the like) are contained on the basal plane or edge of Graphene Oxide (GO), and the groups endow the GO with excellent dispersibility, hydrophilicity, compatibility with a substrate and the like, and simultaneously a reaction site is provided for functional modification of the GO, so that a large number of GOs formed by stacking the sheets have excellent separation performance. However, the space of the nanometer scale of the GOM limits the transmission of water molecules in the membrane, the retention performance is maintained, the water flux is limited, the reduction of the water flux can cause the problems of low efficiency and high consumption, and the existing regulation and control method of the internal structure of the GOM mainly regulates the pore structure, the interlayer spacing, the order degree of the layered structure and the like of the GO nanometer sheets. The current method for preparing the GO/Al 2O3 composite ceramic ultrafiltration membrane is to directly deposit graphene oxide on the alumina ultrafiltration membrane by using a vacuum filtration method, the GO cannot be effectively embedded or inlaid in the method, the membrane layer structure degree of GOM cannot be regulated and controlled, membrane layering or interlayer expansion phenomenon is likely to occur, and the membrane separation performance is greatly reduced. Disclosure of Invention The invention aims to overcome the existing defects, and provides the preparation method of the GO/Al 2O3 composite ceramic ultrafiltration membrane, which has the advantages of simple process flow, environmental friendliness, smaller pore diameter of the ceramic membrane and stronger permeability, and can effectively solve the problems in the background technology. In order to achieve the aim, the invention provides the following technical scheme that the preparation method of the GO/Al 2O3 composite ceramic ultrafiltration membrane comprises the following steps of: Weighing graphene oxide, pouring the graphene oxide into a container, adding distilled water, stirring and dispersing on a constant-temperature water bath magnetic stirrer, and then performing ultrasonic dispersion by using an ultrasonic dispersing instrument to obtain graphene oxide dispersion liquid; Weighing pseudo-boehmite, dissolving the pseudo-boehmite into graphene oxide dispersion liquid, placing the graphene oxide dispersion liquid on a constant-temperature water bath magnetic stirrer for stirring and dispersing, then dripping calculated nitric acid by using a constant-pressure dropping funnel, and continuing stirring and peptizing to obtain GO/AlOOH mixed sol; Step three, weighing PVA solution with the mass of 1:1 and GO/AlOOH mixed sol, and stirring the PVA solution and the GO/AlOOH mixed sol to obtain coating liquid; And fourthly, coating a film on the surface of the matrix by using an impregnation method, and drying and calcining at a high temperature to obtain the GO/Al 2O3 composite ceramic ultrafiltration membrane. Preferably, in the first step, the mass ratio of the graphene oxide to the pseudo-boehmite is 1:50-1:200, and the ultrasonic time is 0.5-2 h. Preferably, in the second step, the mass ratio of the pseudo-boehmite to the water is 1:10-1:20, and the molar ratio of the nitric acid to the pseudo-boehmite is 1:5. Preferably, in the second step, the temperature of heating and stirring is 25 ℃, and the peptization time is 5-40 min. Preferably, the PVA solution added into the film coating liquid in the third step is a film forming agent, and the concentration of PVA is 2% -4%. Preferably, the substrate material used for the coating film in the fourth step is alumina, zirconia or silicon carbide porous ceramic or porous ceramic microfiltration membrane. Preferably, the drying system of the composite ceramic ultrafiltration membrane in the fourth step is that the drying temperature of a forced air drying oven is 60-80 ℃ and the drying time