A comparative study of conventional chemical deinking and environment-friendly bio-deinking of mixed office wastepaper

Abstract

Bio-deinking is an environmentally friendly process that improves the pulp and paper properties and reduces chemical consumption during the recycling of waste paper. This study was performed to evaluate the efficacy of enzyme by Penicillium sp. AKB-24. Chemical deinking of MOW showed freeness (CSF), pulp brightness (ISO), deinking efficiency, and dirt count by 426±4 ml, 75.55±0.1%, 82.13±0.7%, and 733±24 mm2/m2 respectively at optimum repulping parameters. The physical strength properties including burst index, tear index, tensile index and double fold numbers were found 2.97±0.14 kPa.m2/g, 11.14±0.61 mN.m2/g, 46.60±1.99 N.m/g, and 36±2 respectively during chemical deinking of MOW. The deinking chemicals including NaOH, Na2SiO3, and H2O2 were replaced with crude enzyme by Penicillium sp. AKB-24 during enzymatic deinking of MOW. Enzymatic deinking of MOW resulted in an improvement in pulp freeness by 18.30% compared to chemical deinking while the dirt count value decreased by 32.60% during enzymatic deinking of MOW. Physical strength properties such as burst index, tensile index, and double fold numbers were improved by 16.07%, 14.54% and 8.57% respectively while tear index was decreased by 11.61% during enzymatic deinking of MOW compared to chemical deinking.

Keywords

• Cellulase deinking
• Recycling
• Deinking efficiency
• Brightness
• Repulping