Pulp cellulose content refers to the ratio of the mass of cellulose in pulp to the total mass of pulp, and is one of the important indicators of pulp. There are two main methods for determining pulp cellulose content: heating acid hydrolysis and enzymatic hydrolysis.
heating acid hydrolysis
principle
The pulp sample is heated to a certain temperature, and then acid-hydrolyzed with a dilute acid solution to dissolve non-cellulose substances, then filtered and washed, weighed after drying, and the cellulose content is calculated.
Instruments and Reagents
Heater: used to heat pulp samples;
Balance: used for weighing;
Test tube: for acid hydrolysis;
Dilute acid: Usually 2% sulfuric acid or sodium hydroxide is used.
Steps
Take a certain amount of pulp sample and add it to the test tube.
Heat the test tube to 90-100°C for 1 hour to dissolve the non-cellulosic matter in the pulp.
Add dilute acid solution for acid hydrolysis to precipitate cellulose.
The solution was filtered and the precipitate was washed clean.
Dry the pellet in a desiccator until completely dry.
The dried precipitate was weighed to calculate the cellulose content.
enzymatic method
principle
Cellulase is used to hydrolyze the cellulose in the pulp into sugars, and then the content of sugars is determined by the phenol-sulfuric acid method, and then the cellulose content is calculated.
Instruments and Reagents
Enzymolysis instrument: used to control the temperature and time of enzymolysis;
Phenol-sulfuric acid reagent: for the determination of sugar content.
