Enzymatic Deinking of Office Waste Papers in Comparison with Conventional Chemical Deinking: part 2-physical and strength properties of paper

Mixed office waste deinking by conventional chemical process, other than having higher chemical consumption and considerable emission of environmental pollutions, has relatively lower deinking efficiency. On the other hand, enzymatic deinking increases deinking efficiency even at reduced environmental pollutions, but it may reduce the strength properties of deinked pulp. At present paper, the physical and strength properties of mixed office waste enzymatic deinked pulps, selected from superior enzymatic treatments in terms of deinking efficiency using commercial cellulase enzyme from Aspergillus niger, were compared with the selected superior samples of chemical deinking treatments and the reference sample. The results showed that, the hand sheets of enzymatic deinked pulps, in comparison with chemical deinking, had lower caliper and bulk but without having significant differences with chemically deinked pulps in terms of the strength properties. As a result, because of its better deinking efficiency and also acceptable physical and strength properties, enzymatic deinking was recommended, as a proper substitute of conventional chemical deinking, for deinking of mixed office waste papers.