This set of Food Processing Unit Operations Multiple Choice Questions & Answers (MCQs) focuses on “ Membrane Separation”.
1. What are the classifications of membrane separation?
a) Pore size
b) Separation driving force
c) Separation driving pressure
d) Separation driving force and pore size
Explanation: Membrane separations are classified by pore size and by the separation driving force. It is a technology which selectively separates materials via pores and minute gaps in the molecular arrangement of a continuous structure.
2. What is pore size of RO membranes?
a) 0.0005 microns
b) 0.005 microns
c) 0.05 microns
d) 0.5 microns
Explanation: The pore size of RO membrane is 0.0005 microns, this is smaller than the size of the sodium chloride molecule which has the size of 0.0007 micron and will not let it through membrane.
3. What are the applications of membrane separation?
a) Nano filtration
d) Microfiltration, ultrafiltration, nano-filtration
Explanation: The membrane processes are used in microfiltration, gas separation, ultrafiltration, membrane distillation, nanofiltration, reverse osmosis, electrolysis, dialysis, electro dialysis and membrane contactors.
4. What is filter membrane made up of?
a) Thin layer of collodion, cellulose acetate
b) Thick layer of collodion, cellulose acetate
c) Thin layer of collodion
d) Thin layer of cellulose acetate
Explanation: The membrane filter is a filter which is made up of a thin film of collodion, cellulose acetate, available in a wide range of defined pore sizes.
5. What is permeate?
a) Fluid that has retained in semi-permeable membrane
b) Fluid that has passed through semi-permeable membrane
c) Fluid that has to be passing through semi-permeable membrane
d) The residue after filtration
Explanation: The membrane separation system splits stream into two fold effluent streams. They are permeate and concentrate. Permeate is defined as the fluid that passes through the semi-permeable membrane.
6. Are these statements about the membrane separation process true?
Statement 1: It replaces the conventional processes like filtration, distillation, ion-exchange and chemical treatment systems.
Statement 2: Greater flexibility in designing systems.
a) True, False
b) True, True
c) False, True
d) False, False
Explanation: Advantages of membrane separation process are appreciable energy saving, clean technology with operational ease and it replaces the conventional processes like filtration, ion-exchange and chemical treatment systems and finally greater flexibility in designing systems.
7. What are classification of membranes from a structural point of view ?
a) Asymmetrical and pore size
b) Symmetrical and pore size
c) Symmetrical and asymmetrical
d) Symmetrical and concentration of solute
Explanation: From a structural point of view membranes are broadly divided into two types. They are Symmetrical and asymmetrical which is also called as anisotropic.
8. What are the driving forces in membrane separation?
a) Osmotic pressure
b) Electrical field
c) Partial pressure
d) Osmotic pressure, electrical field and partial pressure
Explanation: The driving forces in membrane separation are transmembrane (hydrostatic) pressure (TMP), concentration or electrochemical gradient, osmotic pressure electrical field and partial pressure.
9. Is micro filtration is used to remove biological entities in the 0.25 μm to 5.0μm range?
Explanation: The micro filtration is used to remove biological entities in the 0.025 μm to 10.0μm range from fluids by passage through a microporous medium like a membrane filter.
10. Which of the following are in the order of descending order?
a) Nano filtration, ultrafiltration, Reverse osmosis and microfiltration
b) Reverse osmosis, nano filtration, ultrafiltration and microfiltration
c) Microfiltration, ultrafiltration, nano filtration and reverse osmosis
d) Ultrafiltration, microfiltration, nano filtration and reverse osmosis
Explanation: Membrane processes are classified into four types based on size of component in the feed solution. The descending orders are microfiltration, ultrafiltration, nano filtration and reverse osmosis.
Sanfoundry Global Education & Learning Series – Food Processing Unit Operations.
To practice all areas of Food Processing Unit Operations, here is complete set of 1000+ Multiple Choice Questions and Answers.