How to measure pulp ash and acid insoluble ash content?
Pulp ash and acid-insoluble ash content are two important indicators for evaluating pulp quality, and their determination methods are as follows:
Determination method of pulp ash content
The ash content of pulp refers to the percentage of the mass of non-organic components in pulp to the total mass of pulp after drying at 110°C. The determination method usually adopts the standard GB/T 2677.4-1993 "Determination of Inorganic Substances in Paper and Cardboard". The specific operation steps are as follows:
Take a certain amount of pulp sample, about 5g, and place it in the ash measuring cup.
Put the ash measuring cup into a high-temperature oven and dry it at 110±2°C for 2 hours.
Remove the ash measuring cup and let cool to room temperature.
Put the ash measuring cup on the electronic balance for weighing, and record the weighing value.
Put the ash measuring cup into an oven, and dry it at 815±10°C to constant weight.
Remove the ash measuring cup and let cool to room temperature.
Put the ash measuring cup on the electronic balance for weighing, and record the weighing value.
Calculate pulp ash content: pulp ash content (%) = (mass after drying - original mass) / sample mass × 100%.
Method for determination of acid-insoluble ash content
Acid-insoluble ash content refers to the percentage of the mass of non-organic components in pulp to the total mass of pulp under certain acidic conditions. The determination method usually adopts the standard GB/T 2677.6-1994 "Determination of Acid Insoluble Matter in Paper and Cardboard". The specific operation steps are as follows:
Take a certain amount of pulp sample, about 2g, and place it in a conical flask.
Add a certain volume of HCl (5%) to fully infiltrate the sample.
Heat the flask in a boiling Water Bath to separate the fibers in the sample, and keep heating until all the fibers in the sample are separated.
Take out the Erlenmeyer flask, and wash the sample with deionized water until the acidity in the washing solution is lower than PH=6.
Put the flask into an oven and dry it at 105±2°C to constant weight.
Take out the flask and cool to room temperature.
