Which one among the following is used in bleaching of paper ?

Which one among the following is used in bleaching of paper ?

[amp_mcq option1=”Chloride” option2=”Chlorobenzene” option3=”Ammonium chloride” option4=”Hydrochloric acid” correct=”option1″]

This question was previously asked in
UPSC CDS-2 – 2024
Chloride (referring to chlorine-based compounds) is used in the bleaching of paper.
Bleaching of paper pulp is primarily done using oxidizing agents to remove lignin and whiten the pulp. Historically, elemental chlorine (Cl₂) was used, but it has largely been replaced by more environmentally friendly chlorine-based compounds like chlorine dioxide (ClO₂) or processes using oxygen, hydrogen peroxide, or ozone. Among the given options, “Chloride” is the most general term that points towards the use of chlorine-based bleaching agents.
Options B (Chlorobenzene) is an organic solvent and chemical intermediate, not a paper bleach. Option C (Ammonium chloride) is a salt used in various applications but not paper bleaching. Option D (Hydrochloric acid) is a strong acid, used in some industrial processes but not as the primary bleaching agent for paper pulp.