In this work, a xylanase-producing strain, Streptomyces griseorubens LH-3, was cultured, and the crude xylanase was prepared. Analysis of its enzymatic properties revealed that the crude xylanase possessed good thermal stability at temperatures below 60 o C, exhibited a wide pH range from 4.0 to 9.0, and was cellulase-free. This crude enzyme was used to treat eucalyptus kraft pulp, and the rele...

The lipophilic extractives of Eucalyptus globulus, Eucalyptus grandis, Eucalyptus urograndis, Betula verrucosa and Acacia mangium woods and of the corresponding ECF bleached kraft pulps, were characterized by GC-MS. The five hardwoods showed significant differences in the content and composition of the main families of extractives, namely fatty acids, long chain aliphatic alcohols and sterols. ...

In this study, several kraft pulps were produced by kraft pulping of fastgrowing Eucalyptus with a wide range of cooking conditions. The dependences between pulp yields and some pulp properties, namely, kappa number, HexA contents, and cellulose viscosities, were well investigated. It was found that kraft pulp yields linearly decreased with the reduction of HexA-free kappa number in two differe...

A variety of the Leucaena genus, Leucaena diversifolia, was used for pulp and paper making by kraft and refining processes and a OD(EP)DP bleaching sequence. The same species has been suggested as an energy crop and, in fact, this species used shows a high gross heating value; besides, this variety of Leucaena has appropriate characteristics for pulp and paper making. The holocellulose content ...

The addition of aluminum nitrate (up to 100 ppm A1 on pulp) to a two-stage, acidalkali, hydrogen peroxide bleach of Eucalyptus regnans stone groundwood pulp enhanced the brightness gain of the pulp, over a range of consistencies. It is proposed that the presence of aluminum ions modifies the catalytic behaviour of the transition metal ions present in the pulp, especially manganese, reducing per...

Eucalyptus is a species of great interest for the pulp and paper industry. Worldwide there are 20 million hectares planted and within Chile a total of 700.000 ha, being the main species grown for short-fibre pulp Eucalyptus globulus, which is extensively used for pulping due to its fast growth, high pulp yield, and good fiber properties. Genetic programs of this specie have been oriented in imp...

Eucalyptus (Eucapyptus spp.), an evergreen tall tree native to Australia and Tasmania, has been used since ancient times by the aboriginal population for several purposes. In particular, the species E. globulus is widely used in the pulp industry, as well as for the production of eucalyptus oil extracted on a commercial scale in many countries as raw materials in perfumery, cosmetics, food, bev...

Vermiculite, pine shavings and unbleached eucalyptus pulp contact-bedding were compared using the number of litters and individuals born and weaned, mortality rates at different stages of the lactation period, and the weight increase of pups as evaluation indices for bedding quality. These bedding materials exerted different effects on the reproductive performance of the same mouse strain. The ...

Thermal and infrared spectroscopic analyzes were carried out in order to study the kind of interaction between the anatomical components of the bleached eucalyptus kraft pulp with offset inks. A Bauer-McNett fiber classifier was used in order to obtain the anatomical components of the pulp, separately. The determinations of the enthalpy of the processes occurring in the samples of inks and pulp...