Question

The _______ uses sodium sulfite and a small amount of sodium hydroxide or sodium carbonate to give slightly alkaline liquor.

(a) Basic-sulfite semichemical (NSSC) process

(b) Acidic-sulfite semichemical (NSSC) process

(c) Neutral-sulfite semichemical (NSSC) process

(d) Alkaline-sulfite semichemical (NSSC) process

The question was posed to me in an interview for internship.

The doubt is from Chemical Pulping & Semichemical Pulp in division Paper and Paper Based Packaging Materials of Food Packaging Technology

Answer 1

The correct option is (c) Neutral-sulfite semichemical (NSSC) process

To elaborate: The neutral-sulfite semichemical (NSSC) process (applied mainly to hardwood chips) uses sodium sulfite and a small amount of sodium hydroxide or sodium carbonate to give slightly alkaline liquor. The NSSC pulp is obtained in higher yield but with higher lignin content than in the other sulfite processes. It is used mainly for the manufacture of corrugating medium.