Using amylases to optimize the desintegration process

The rising utilization Mixed Office Waste (MOW) as a source of secondry fiber makes necessary to develop news tecnologies to make this secondary fiber grade suitale for the manufacturee of higgh brightness printing paper. Deinking this kind of paper is necessary to achieve the required properties. But the deinking operation is as impotant as the previous desintegration operation. This desintegration could be improved by biotechnology. Amylases are enzymes which hydrolyze starch and, in this work, they were used to remove the starch in the paper and, thus, to reduce the cohesion of the sheet, making the disintegration easier We have not found studies about this subject in the bibliography. For this work, special inkjet printer paper was used because its desintegration is much more difficult than in the case of using standard printing paper. Moreover, a method to assess the action of the enzymee based on the remaining flakes in the pulp after standard lab desintegration is proposed. The study was split in two different parts in which two different statistical plans were carried out. In to first part, a special inkjet printer paper was compared with a standard printing paper, suitable for photocopiers. The results of the first part showed thatt the inkjet printer paper was more difficult to desintegrate than the standard one. The effect of a commercial amylase was evaluated in the second part. A statistical plan was used to perform the study in which the variables were the enzime dose (1,6 to 5%), the treatment time (20 yo 60 min) and number of revolutions of a standard laboratoy desintedgrator (15.000 to 65.000 revolutions). Two different responses were evaluated: the flakes amount after enzymatic treatment and desintegration and the remaining starch in the pulp after enzymatic treatment. The results of the second part showed that the enzyme had a significant effect on the final flakes amount in the pulp. The conclusion is that a previous treatment with amylases makes the desintegration easier, so it if posible to obtain pulp in better conditions to be deinked.