WOOD RESEARCH Volume 71, Number 2, 2026
MONIKA STANKOVSKÁ, ALBERT RUSS, ANDREJ PAŽITNÝ, ŠTEFAN BOHÁČEK, Elena Opálená, and JURAJ KRIŠTA

THE COMPARISON OF METHODS FOR THE PREPARATION OF FIBRILLATED CELLULOSE FROMDISTILLERY CORN REFUSE USING STEAM EXPLOSION

This study proposes a novel approach involving steam explosion for the production of fibrillated cellulose using distillery refuse as a by-product of bioethanol production. The effect of the steam explosion with or without additional pre-treatment or post-treatment of distillery refuse on lignin and hemicellulose degradation was studied by infrared spectroscopy and fibre length distribution. Partial decomposition of hemicellulose was observed after the use of steam explosion combined with acid-alkali pre-treatment. The process was less effective by using steam explosion, followed by oxidation and bleaching, however, it showed better results in comparison with steam explosion followed by single oxidation. Steam explosion combined with acid-alkali pre-treatment or with oxidation combined with bleaching effectively decomposed lignin. Average arithmetic fibre length after treatment by single steam explosion rapidly decreased but additional treatments no longer caused its further decline. The application of fibrillated cellulose obtained by a single steam explosion on the filter decreased the average pore size. Anchoring of metal salts combined with fibrillated fibres on paper surface was confirmed by SEM-EDS and its ability to act as a barrier against microorganisms was proved.

WOOD RESEARCH Volume 70, Number 4, 2025
ANDREJ PAŽITNÝ, JURAJ KRIŠTA, and MARTA PÁTEKOVÁ

IMPROVING SHEET MATERIAL PROPERTIES IN PAPERMAKING FROM SECONDARY FIBER AND CORN KERNEL’S CASING

The paper is focused on monitoring the impact of corn kernel’s casing content added to old corrugated containers on density, brightness, ultimate tensile load, tensile index, tensile energy absorption, breaking length, tensile strength, relative elongation, air resistance of paper sheet according to Gurley and zero-span tensile strength. A content of 40 % and 60 % corn kernel’s casing added to secondary fiber based on old corrugated containers was tested. Suspensionsprepared by acidification and beating were subjected to chelation and three-stage bleaching.The bleaching method consisting of three steps was applied in two series – acidified and beaten pulp suspension with Schopper-Riegler (°SR) beating degree at level of 72 °SR.The first bleaching step includedperoxide bleaching with added sodium hydroxide, chlorine dioxide bleaching and peroxide bleaching in an alkaline environment. The effect of chemical and hydro-mechanical treatment on the resulting physical and mechanical characteristics of prepared paper sheets was investigated.

WOOD RESEARCH Volume 69, Number 4, 2024
MONIKA STANKOVSKÁ, JURAJ KRIŠTA, ŠTEFAN BOHÁČEK, ALBERT RUSS, and ANDREJ PAŽITNÝ

COMPARISON OF TWO METHOD FOR ISOLATION OF FIBRILLATED CELLULOSE FROM LIGNOCELLULOSIC BIOMASS

Fibrillated cellulose from distillery refuse based on maize starch was prepared by two different procedures. The effect of sonification was evaluated atacid-alkali extractionas well as the type of used acid. The results from the alkali-acid procedure were compared with these obtained by method of steam explosion at different temperatures. The acid-alkali method brings a better result regarding degradation of hemicellulose and lignin as well as cellulose. Lignin/hemicellulose were only released from lignocellulose network using steam explosion at 120-180°C. At higher temperature, the results were comparable with those obtained by acid-alkali method. Similarly pore size distribution of filter paper decreased more significantly when fibrillated cellulose from acid-alkali treatment was applied. After steam explosion, higher extend of longer still fibres remains

WOOD RESEARCH Volume 69, Number 4, 2024
ALBERT RUSS, ANDREJ PAŽITNÝ, JURAJ KRIŠTA, EMMA WESZELOVSZKÁ, and VLADIMÍR IHNÁT

ENZYMATIC HYDROLYSIS OF STEAM EXPLODED STRAW WITH THE ADDITION OF ACETIC ACID

The effect of steam explosion on the enzymatic hydrolysis of straw was investigated in the presence of 5, 10, 15 and 20% wt. addition of acetic acid. Analysis was performed at temperatures of 160, 170, 180, 190, 200 and 210°C. The concentration of monosaccharides obtained after enzymatic hydrolysis was considered the main indicator of the increased availability of cellulose due to their release into the solution. The results indicate that the addition of acetic acid increases the concentration of monosaccharides, but only at lower temperatures. The temperature of 180°C corresponded to the most effective pretreatment by steam explosion in the presence of acetic acid with the highest concentration of 10%, which corresponds to the conversion of polysaccharides to monosaccharides of 74.78%. At high temperatures above 200°C, the addition of acetic acid results in a decrease in the concentration of monosaccharides due to the high severity factor in the range of 3.94 – 4.24