STUDIES ON XYLANASE AND LACCASE ENZYMATIC PREBLEACHING TO REDUCE CHLORINE-BASED CHEMICALS DURING CEH AND ECF BLEACHING

The biobleaching efficiency of xylanase and laccase enzymes was studied on kraft pulps from wood and nonwood based raw materials employed in the Indian paper industry. Treatment of these pulps with xylanase enzyme could result in improved properties, showing 2.0% ISO gain in pulp brightness and/or reducing the demand of chlorine-based bleach chemicals by up to 15% with simultaneous reduction of 20 to 25% in AOX generation in bleach effluents. Further, mill-scale trial results revealed that enzymatic prebleaching can be successfully employed with xylanases to reach the same bleach boosting efficacy. Laccase bleaching was also studied on hardwood pulp at a pH around 8.0, where most of the pulp mills in India are operating, in contrast to earlier studies on laccase enzyme bleaching, which were conducted at acidic pHs, i.e. 4.0 to 5.0. In case of laccase bleaching, interesting results were found wherein a bleach-boosting effect was observed even at pH 8.0. Further studies carried out with HOBT as mediator in comparison to the commonly used and expensive ABTS laccase mediator system (LMS) resulted in improvement of the bleaching efficiency with reduction in demand of chlorine dioxide by more than 35%. Potential for further reduction was indicated by the brightness gain, when compared with a control using the DE(p)D bleach sequence

Trace the Best Factor by Path Analysis for the Under-Five Mortality Deaths in India

The outcome of the paper is to trace the best factor by the path analysis and effect of Total Fertility Rate on under five mortality rates in India and also to analyze other socio economic factors affecting for the development of a region or a community or a country. The under five mortality rate, preschool children mortality rate and Total fertility rates have been observed. The most affected factors have been identified among the few variables and analyzed from the available data. Employed Statistical and Mathematical application; Path Analysis technique, Regression analysis technique and found correlation matrices as well as descriptive values. It has been high proportion of Total fertility rate R2, affected the under five mortality rate in India. Identified the direct and indirect effects by the Path analysis technique, fitted Regression and path models