Question

The commonly used filter aid is...........

• A. Cellulose acetate
• B. Solid cake
• C. Kieselguhr
• D. Glass fiber

Hint:

Kieselguhr = Diatomaceous Earth. It's the secret to getting crystal-clear beer and apple juice without clogging expensive equipment.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
The question asks to identify a standard material used as a "filter aid" in the food and beverage industry to prevent the clogging of filters and improve clarity.

Step 2: Detailed Explanation:

• Some fluids (like fruit juices, beer, or syrups) contain fine, slimy, or gelatinous particles that quickly form a non-porous layer on the filter medium, stopping the flow. This is called "blinding" the filter.

• A filter aid is a chemically inert, porous material added to the liquid before filtration or applied as a "pre-coat" on the filter.

• Kieselguhr (also known as Diatomaceous Earth or DE) is the most common filter aid. It consists of the fossilized skeletons of microscopic algae called diatoms.

• These skeletons have very intricate, porous shapes that create a highly permeable "cake" during filtration. This cake traps the impurities while allowing the liquid to pass through freely.

• Other filter aids include perlite, cellulose, and asbestos (rarely used now for safety).

• Cellulose acetate is a membrane material. Glass fiber is a filter medium itself, not an "aid" in the traditional sense.

Step 3: Final Answer: Kieselguhr is the most commonly used filter aid in industrial filtration.