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In this study, a chemical reduction strategy was explored for deinking of newspaper waste using xylano-pectinolytic catalysts. A remarkable reduction of 40% in toxic chemicals consumption was obtained by introducing this enzymatic approach of deinking along with improved level of various physical and optical properties. Similarly, a reduction of 18.89% and 17.68% in BOD, COD values of effluent has also been noticed. This combined deinking methodology also resulted in a gain of 5.82% in breaking length, 6.45% in tear factor, 8.57% in burst factor and 9.64% in viscosity, which greatly improved the quality of the handsheets. The study revealed that enzymatic deinking followed by chemical deinking with 40% less chemicals consumption, could be an effective method for reducing the negative impact over the environment caused by 100% deinking chemicals. This is the first report of newspaper waste deinking using xylano-pectinolytic catalysts produced concurrently in the same production media by a bacterial isolate using agricultural wastes as carbon sources.

The effect of ultrafiltered xylanase–pectinase concoction produced simultaneously by a bacterial isolate using agro-waste-based media was assessed in prebleaching of plywood waste pulp. Ultrafiltered enzymes caused 12.5% reduction in kappa number at reduced enzyme dose of xylanase–pectinase (4.0–0.8 IU) per gram of pulp under optimized conditions at pH 8.5, temperature 55 °C, and treatment period of 2 h. Using this methodology, amount of Cl2–ClO2 consumption can be reduced up to 30 and 28.86%. Significant improvement in physical and optical properties of pulp was obtained along with an additional reduction in BOD and COD values up to 18.13 and 21.66% using this novel biodelignification approach. This is the first report showing the advantages of using ultrafiltered xylanase–pectinase over crude enzymes in enhancing the bleaching capacity of pulp. This study focussing on the development of good quality paper with less pollution generating strategy will definitely prove a boon for industries.

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Mixed hardwood chips were treated with lignin-degrading fungi to study the effect of fungal pretreatment on bleaching characteristics of kraft pulp. Pretreated wood chips were subjected to reduced active alkali doses in comparison to untreated chips. Comparable results were obtained for pretreated chips with reduced alkali dose as was obtained with higher dose of alkali in case of untreated chips. Fungal treatment made the process more energy-efficient, and 4.8% less chlorine was consumed in comparison to the control process. Pretreatment with Ceriporiopsis subvermispora was responsible for reduction of 4.7% in lignin contents, 14.3% permanganate number, and overall reduction of 15.5 kg/T of Cl2 consumption. The pollution load in terms of COD and BOD at the CD stage was reduced by 32.6% and 41.5% respectively, whereas 12% reduction in AOX compounds was observed in effluent of pretreated pulp.