For papermaking industry, paper for recycling represents a possiblility to extract secundary fibers for re-use. Every industry's priority is to obtain high-quality paper with the lowest level of environmental impact and low cost. The convencional deinking using chemicals represents environmentally damaging process. Biodeinking, using enzymes, represents environmentally friendly and better solution from economical point of view.
Comparing with convencional deinking process it was aimed to achieve similar results with encymatic deinking, combining lower values of chemicals. Theoretical part includes explanation of key deinking steps and indication of previous researches in the field of encymatic treatment of cellulose fibers. In the practical part of this study various types of recycled paper were used and they contained 60 – 70% of old newspaper and magazines. The majority of samples were printed with offset inks (95%), the rest of samples contained inks of other printing technologies. In the process, there was a combination of low amount of chemicals and encymes like cellulase, lipasse and laccase. Deinking procedure involved basic steps of convencional deinking process – preparation of samples, pulping, enzymatic and chemical treatment, flotation, papermaking and evaluation of mechanical and optical properties.
Encymatically threated samples (in combination with chemicals) achieved better mechanical and optical properties. All off the used enzymes fulfilled better results of ISO brightness, especially combination of cellulase and lipasse. The lowest value of ISO brightness was obtained in encymatic deinking with lipasse individually.
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