The influences of pulp type, content of acidic groups (i.e., sulfonic and carboxylic groups) in CTMP, kappa number (i.e., residual lignin content) of unbleached kraft pulp, and beating degree of bleached kraft pulp on the conductivity of polyaniline (PAn)-coated conductive paper were investigated. The amounts of PAn coated on chemical pulps were higher than those coated on high yield pulps, and...

The current global conditions provide the pulp mill new opportunities beyond the traditional production of cellulose. Due to stricter environmental regulations, volatility of oil price, energy policies and also the global competitiveness, the challenges for the pulp industry are many. They range from replacing fossil fuels with renewable energy sources to the export of biofuels, chemicals and b...

Bacillus subtilis, locally isolated, produced significant level of xylanase activity in the presence of different carbon sources. However, B. subtilis performed well when grown on pretreated natural substrates such as rice straw, wheat straw, bagasse, wheat bran and kraft pulp at 2% concentration. The organism produced higher level of xylanasse activity when bagasse was used as a carbon source ...

Consumption of chemicals during ECF bleaching of kraft pulp correlates reasonably well with kappa number, which measures with KMnO4 the total amount of oxidizable material in the pulp. However, the method does not distinguish between the oxidizable material in residual lignin and other structures susceptible to oxidation, such as hexenuronic acids (HexAs), extractives and carbonyl groups in the...

The growing demand for rayon and cellulosic products has resulted in the conversion of a number of kraft pulp mills into dissolving pulp mills in recent years. In fact, kraft-based dissolving pulp production fits well into the concept of an integrated forest biorefinery, in particular, the utilization of dissolved organics in the pre-hydrolysis liquor (PHL) for bio-materials and bio-energy purp...

INTRODUCTION Arundo donax, Poaceae, commonly known as “nalgrass,” is a member of the reed family that grows both wild and cultivated in California. Evaluated as a potential paper fiber source in Italy and Hungary over 50 years ago and included in the 1970s USDA evaluation of potential annual fiber crops, the high potential of A. donax has not been widely recognized. A new evaluation was begun i...

In this study, multifunctional alkaline pulping was suggested to produce different pulp grades at one mill site, ranging from high-yield paper pulp to high-purity dissolving pulp. In all process modifications, sulfur was successfully replaced by anthraquinone. Autohydrolysis and alkaline pre-extraction were applied to Eucalyptus globulus wood chips, followed by kraft and soda-AQ pulping. Alkali...

The dark colour of kraft pulp after the wood chips have been heated at high temperature with NaOH solution is caused by lignin (a complex phenolic polymer) still attached to the cellulose fibres. Traditionally this pulp is treated with chlorine to bleach the pulp to make it suitable for paper making. Unfortunately this leads to the formation of some potentially toxic chlorophenolic compounds of...

The anatomical structure and chemical composition of the stem-wall material of giant reed is considered from the viewpoint of raw material characterization for industrial fiber production. The effect of stem morphology (nodes and internodes) on pulping results and general pulp properties is discussed. The advantages of application of modern organic solvent based (organosolv) pulping technologie...

Environmental regulations coupled to market pressures have forced the pulp and paper industry to explore alternatives to chlorine based bleaching practices for the production of bleached kraft pulp.Various technologies and bleaching chemicals have been suggested as answers to kraft pulp bleaching concerns, from which oxygen, ozone and peroxides are the leading candidates for chlorine replacemen...