Membrane Synthesis
Materials Used
Polysulfone polymer beads (9.6 grams), N-methyl-2-pyrrolidone (NMP) solvent (40 ml), Non-woven fabric
sheet (used as support), Glass plate, Acetone (cleaning agent), Roller (casting machine), Clips, Distilled
water,
Synthesis of membrane
1. Clean a laboratory glass bottle and dry it in an oven at 65°C for an hour to remove contaminants.
2. Polymer-Solvent Mixture Preparation: Weigh 9.6 grams of polysulfone polymer and mix it with 40
ml of NMP solvent. Stir and heat the mixture at 65°C for 12-15 hours, ensuring prior cleaning of stirring
equipment with acetone.
3. Solution Drying: After stirring later Let it dry for 24 hours to allow complete solvent evaporation.
4. Non-woven Fabric Support Preparation: Cut a non-woven fabric sheet to match the glass plate’s size,
which will provide mechanical stability during membrane casting.
5. Glass Plate and Roller Cleaning: Thoroughly clean the glass plate with acetone to remove any water or
contaminants. Clean the bottom of the roller with acetone.
6. Membrane Casting: Place the glass plate under the roller and secure the non-woven fabric sheet with
clips. Adjust the gap between the roller and non-woven fabric sheet using a gauge to achieve a desired
membrane thickness of 200 micrometers.
7. Solution Application: Pour the polymer-solvent solution onto the non-woven fabric support covering
the entire surface. Use the roller at 30 to 35 RPM to evenly distribute the solution with one manual
pass.
8. Phase Inversion and Membrane Treatment: Immediately immerse the resulting membrane attached
to the support in distilled water at room temperature. Allow the membrane to stay in the water for 24
hours for the phase inversion process to complete.
Preparation of piperazine (PIP) solution
Procedure:
Prepare a stock solution containing 0.5% PIP and 0.1% SLS in algal water according to the preprepared
solution.
1. Preparation of piperazine (PIP) Solution: Weigh out 300 mg of PIP accurately using a balance and
transfer it to a clean, dry bottle.
2. Addition of Algal Water: Add 60 ml of algal water to the bottle containing the measured PIP.
3. Addition of sodium lauryl sulfate (SLS): Add 60 ml of SLS solution to the same bottle.
4. Stirring: Place the bottle on a magnetic stirrer and stir the contents for 1 hour at room temperature.
5. Final Steps: After stirring, ensure the solution is homogeneous and no visible particles are present.
Label the bottle appropriately with the contents and concentration.
Preparation of TMC solution
Procedure:
1. Clean the bottle thoroughly with distilled water to remove any contaminants. Ensure it is completely
dry. Heat the cleaned bottle properly
2. Preparation of Solution: Measure out 20 ml of hexane accurately and add it to the prepared bottle.
3. Addition of TMC: Weigh out 30 mg of 1,3,5-benzene tricarbonyl trichloride and carefully add it to the
bottle containing the hexane.
4. Stirring: Stir the contents using a magnetic stir bar for 1 hour at room temperature. Do not apply heat
during stirring.
5. Final Steps: After stirring, ensure that the TMC is fully dissolved in the hexane solution. Check for any
visible particles or undissolved material. Label the bottle appropriately with the contents and
concentration
TFC membrane preparation:
Procedure:
Preparation of Membrane: Ensure the polysulfone membrane is clean and dry before starting the procedure.
1. Application of PIP: Apply the PIP solution evenly onto the prepared polysulfone membrane surface.
Allow the PIP to spread and absorb onto the membrane surface for 2 minutes.
2. Rolling the Membrane: After 2 minutes, roll the membrane properly using a dry roller. Ensure even
pressure is applied to promote uniform distribution of PIP on the membrane.
3. Application of TMC: Apply the TMC solution onto the membrane surface immediately after rolling.
Allow the TMC to spread and absorb onto the membrane surface for 1 minute.
4. Drying Process: Transfer the membrane into an oven for heating at a temperature range of 65 to 80°C.
Allow the membrane to dry in the oven for 15 to 20 minutes. Monitor the drying process carefully to
prevent overheating or damage to the membrane.
5. Final Steps: After the drying period, remove the membrane from the oven and allow it to cool to room
temperature.
TFN membrane preparation:
Procedure:
1. Preparation of MoS2 Solutions: Weigh out 3 mg of MoS2 (0.1% of Mos2) powder separately.Add
weighted amount of MoS2 powder to containers with 6 ml of PIP solution (0.3% of PIP)
2. Ultrasonication: Place the containers into an ultrasonicator. Ultrasonicate the solutions for 30 minutes
to promote dispersion and uniform mixing of MoS2 nanoparticles in the PIP solution.
3. Application onto Membrane: Pour the MoS2-PIP solution onto the prepared polysulfon membrane
surface. Ensure an even distribution of the solutions across the membrane.
4. Drying Process: Transfer the membrane into an oven preheated to a temperature range of 60 to 75°C.
Allow the membrane to dry in the oven for 60 to 75 minutes until it is fully dried.
5. Rolling the Membrane: After drying, roll the membrane properly using a roller to ensure good contact
between the MoS2-coated surface and the membrane substrate. Apply even pressure during rolling to
promote uniformity.
6. Application of PIP: Apply the PIP solution evenly onto the prepared membrane surface. Allow the PIP
to spread and absorb onto the membrane surface for 2 minutes.
7. Rolling the Membrane: After 2 minutes, roll the membrane properly using a dry roller. Ensure even
pressure is applied to promote uniform distribution of PIP on the membrane.
8. Application of TMC: Apply the TMC solution onto the membrane surface immediately after rolling.
Allow the TMC to spread and absorb onto the membrane surface for 1 minute.
9. Drying Process: Transfer the membrane into an oven again for heating at a temperature range of 65 to
80°C. Allow the membrane to dry in the oven for 15 to 20 minutes. Monitor the drying process carefully
to prevent overheating or damage to the membrane.
10. Final Steps: After the drying period, remove the membrane from the oven and allow it to cool to room
temperature.