SPGIntroduction to membrane

SPGfilm（Shirasu Porous Glass）It's JapanSPGThe company is1981The new type of inorganic membrane developed in the year,SPGThe membrane has consistent and uniform micropores, and the size of the pores can be easily changed,SPGDuring the production process of the membrane, the first step is to mix volcanic ash, glass, and lime1350℃Boric acidformingThen heat it up againarrive700℃aboutGenerate phase change and separation:CaO·B₂O₃andAl₂O₃·SіO₂Make a glassy material with minimal phase separation, and finally place it in acidhandleRemove soluble substances and manually process themafter, containingAl₂O₃·SіO₂ofPorous glass is ultimately formed;The material isProcessed into a certain thickness and shape, that isSPGThe membrane. By changing the preparation conditions, different pore sizes can be obtainedSPGfilmTube and membrane.

1.raw material---〉

2. pass through1350℃Post molding

3. 650C-750℃reprocessing

4. 50-90℃After acid treatment, the finished product is obtained

5. microscopicSPGMembrane surface

SPGThe shape of the membrane

1. tubularSPGMembrane2. FlakySPGfilm

SPG membrane specifications

SPGMembrane emulsification method

1Direct emulsification

The dispersed phase and continuous phase are prepared separately in different containers, and the dispersed phase passes throughSPGThe membrane produces a uniform emulsion, and the continuous phase requires slight flow. The particle size of the emulsion is3-4doubleSPGThe pore size of the membrane.

Aperture=1micron(emulsion=3.0micron)aperture=2micron(emulsion=7.6micron)aperture=5micron(emulsion=14.3micron)

Aperture=10micron(emulsion=31.3micron)aperture=15micron(emulsion=43.1micron)aperture=20micron(emulsion=66.2micron)

2Mixing emulsion

Mixing dispersed and continuous phase solutions together, penetrating throughSPGThe membrane obtains a uniform emulsion, and the particle size of the emulsion is1-2doubleSPGThe pore size of the membrane. (The left side in the picture shows direct emulsification, and the right side shows mixed emulsification)

Regeneration and Reuse of SPG Membrane

1. After emulsification of diesel engine oilSPGfilm

2. exist400℃Under high temperaturehandle2After hoursSPGfilm

3. exist500℃Under high temperaturehandle4After hoursSPGMembrane

4. exist400℃Under high temperaturehandle6SPG membrane after hours

SPGmembrane emulsification

By stirring and mixing two immiscible liquids with an appropriate amount of surface active ingredients, an emulsion can be produced. However, the droplets of the emulsion are highly dispersed and can differ in diameter by several times or even tens of times.

Principle:The dispersed phase passes through the membrane hole of the microporous membrane under the action of nitrogen pressure, and forms droplets on the membrane surface. Under the washing action of the continuous phase flowing along the membrane surface, after the diameter of the droplets reaches a certain value, they peel off from the membrane surface, thus forming lotion. Utilizing uniform aperture sizeSPGThe size and distribution of lotion particles can be well controlled. Due to the relatively uniform diameter of the micropores in the membrane, the droplets produced into the emulsion are also relatively uniform. As long as the composition of the water phase is adjusted and the stability of the droplets is maintained, highly monodisperse emulsion droplets can be obtained, and corresponding polymer particles can be obtained after polymerization.

Application:It is mainly used to prepare lotion, beads, microspheres, microcapsules, etc. with uniform size, and can be preparedW/O、O/W、W/O/W、O/W/ODifferent lotion. Realize the size uniformity of lotion; Controllable surface functionality of microspheres; Stability of porous microsphere structure; Homogeneous lotionofpreparation; Porous microspheres or sustained-release capsules with pore channelscontrolWait.

SPGParticle distribution of membrane emulsion

Particle distribution of emulsion in high-pressure homogenizer

Particle size and distribution:The above picture isSPGThe distribution map of particle characteristics after membrane emulsification, as well as the comparison with high-pressure homogenizer, is shown in the graphSPGAfter membrane emulsification, a uniformly sized emulsion was obtained, which is exactly what we hoped for; Considering the different usage requirements for products during the production process,SPGThe membrane can achieve emulsion with different particle sizes, uniform particle distribution, and product quality90%All particle sizes are within this range; However, the samples obtained using a high-pressure homogenizer contain particles of different sizes, which means that the high-pressure homogenizer cannot obtain stable and uniform products. For example, membrane emulsification can be achieved90%The particles are0.8μmAnd the high-pressure homogenizer is6.0μmThe above particles are also20%.