Particulates can be removed from smokestack emissions by which of the following methods?

• A. Thermal decomposition
• B. Fractional distillation
• C. Catalytic cracking
• D. Electrostatic precipitation

Answer: (D)

Verified step by step guidance

1. Understand the nature of particulates in smokestack emissions: these are tiny solid or liquid particles suspended in the gas stream that need to be removed to reduce pollution.
2. Review the given methods and their typical applications: Thermal decomposition involves breaking down compounds by heat, fractional distillation separates mixtures based on boiling points, and catalytic cracking breaks large hydrocarbons into smaller ones in petroleum refining.
3. Recognize that none of these methods are designed to physically remove solid particles from a gas stream; instead, they alter chemical composition or separate liquids.
4. Learn about electrostatic precipitation, which removes particulates by charging the particles electrically and then collecting them on oppositely charged plates, effectively cleaning the gas stream.
5. Conclude that electrostatic precipitation is the appropriate method for removing particulates from smokestack emissions because it physically captures and removes solid particles from the gas.