ENHANCEMENT OF OPTICAL PROPERTIES OF BA GASSE PULP BY IN-SITU FILLER PRECIPITA TION

Abstract

The present report describes the experimental method and the results of a study conducted to improve the optical properties of bagasse pulp by using in-situ precipitation of calcium carbonate. In-situ precipitation of calcium carbonate in bagasse fibers results in a very significant increase in specific scattering coefficient of the bagasse pulp, and consequently large improvements in opacity and brightness of the handsheets made of such pulp. At the same level of filler loading, the. scattering coefficient of in-situ precipitated pulp was much greater than the direct loaded pulp. In-situ precipitation of calcium carbonate caused a drop in strength properties of bagasse Pulp. All the strength properties of in-situ precipitated bagasse pulp could be improved by blending with either softwood (5%) or hardwood (10%) or wheat straw (7.5%) in furnish. In-situ precipitation of calcium carbonate resulted in a significant reduction of print-through in bagasse handsheets for offset printing. The effect of in-situ precipitation of calcium carbonate on pulp fibers was quite different for bagasse pulp from the hardwood pulp. In-situ precipitation of calcium carbonate on hardwood fibers did not show much improvement in optical properties and the print through. Similarly, the reduction in strength properties of hardwood pulp was also small.