Question

As per the pore size of membrane, state the correct sequence:

• A. NF > MF > UF > RO
• B. MF > UF > NF > RO
• C. UF > MF > NF > RO
• D. RO > MF > UF > NF

Hint:

Remember the order by pore size: {Micro $\rightarrow$ Ultra $\rightarrow$ Nano $\rightarrow$ RO}.

Answer 1

The Correct Option is B

Step 1: Understanding membrane filtration.
Membrane processes are classified based on pore size, which determines the size of particles or solutes removed from water.
Step 2: Relative pore sizes.
Microfiltration (MF) has the largest pore size, followed by Ultrafiltration (UF), then Nanofiltration (NF), while Reverse Osmosis (RO) has the smallest effective pore size.
Step 3: Evaluating the options.
(A) Incorrect, NF does not have larger pores than MF.
(B) Correct, this follows decreasing pore size from MF to RO.
(C) Incorrect, UF pores are smaller than MF.
(D) Incorrect, RO has the smallest pores, not the largest.
Step 4: Conclusion.
The correct sequence according to decreasing pore size is MF > UF > NF > RO.