PAPER making! g! FROM THE PUBLISHERS OF PAPER TECHNOLOGY INTERNATIONAL ® Volume 11, Number 3, 2025
and 170ºC), retention times (45–90 min), and acid:base ratios (a:b = 1.00 to a:b = 0.55) were investigated. Fractionation at 170ºC for 45 min with a reduced acid:base ratio of a:b = 0.86 allowed for maximum delignification (lignin content of 4.4 %) and preservation of fibre length. Pulps recovered under optimal conditions were bleached using a single stage method based on H 2 O 2 increasing pulp purity, achieving optimal decolorization and retaining fibre dimensions comparable to those obtained from a commercial process (Lc(l) = 0.509mm and Lc(w) = 0.775 vs Lc(l) = 0.540mm and Lc(w) = 0.975). This highlights the potential of the ionoSolv process as a greener fractionation alternative to produce cellulose fibre materials. RECYCLING “Terahertz-based identification of waste paper for improved recycling in Japan”, lDai Otsuka, Asami Kawaguchi, Ayaka Abe, Shiho Sasaki, Yusuke Yoshimura, Iori Tomoda & Tadao Tanabe, Waste Management , 202, July 2025, 114795. The identification of different types of wastepaper is important during recycling. In this study, we demonstrate the effectiveness of non-destructive diagnostic testing using terahertz waves. Seven types of paper, including contraband paper, were irradiated with terahertz waves of multiple frequencies over a wide bandwidth, and their transmission characteristics evaluated and contrasted. The experimental results show a negative correlation between the basis weight of the samples and the transmittance of paper pulp, which allows to identification of paper pulp types. These results suggest that terahertz waves can be an effective method for identifying different types of paper pulp. Based on these results, we believe that Terahertz transmission measurements can significantly contribute to the improved recycling of recovered paper resources. “Removal of fillers and chemical reagents from waste paper for its sustainable use”, Marek Kucbel, Helena Raclavská, Jana Růžičková, Michal Šafář, Pavel Kantor, Karolina Slamová & Jarmila Drozdová, Environmental Science and Pollution Research , https://doi.org/10.1007/s11356-025-37133-5. Waste paper represents a valuable secondary source of cellulose fibres, contributing to the reduction of virgin wood consumption in paper production. To support sustainable development objectives, the integration of natural fibres with synthetic polymers is increasingly explored across industrial sectors. Reliable use of waste paper materials requires baseline data on pollutant content and migration potential. In this study, cellulose fibres were separated using 0.2 M acetic acid (CH 3 COOH) extraction, followed by washing. This method effectively removed precipitated calcium carbonate-based filler from office paper, achieving an extraction efficiency of 86%. A total of 138 compounds were identified in waste paper, originating from: virgin wood (n = 31), paper manufacturing and recycling processes (n = 19 + 15 fragrance compounds), and printing inks (n = 67), with solvents (n = 25) forming the largest subgroup. Additional substances were associated with surface treatments and ink formulations. Compound hazard profiles were assessed using the Globally Harmonized System (GHS). The identified substances were, among others, persistent organic pollutants, including benzophenone, butylated hydroxytoluene, and bis(2-ethylhexyl) phthalate, bisphenol A, and bisphenol S, while solvents exhibited the highest proportion of hazardous classifications. Following CH 3 COOH extraction, concentrations of hazardous solvents were reduced by 93%, indicating the method’s potential for pollutant mitigation in fibre recovery. TISSUE “Dimensional Analysis of Absorbency in Paper Towels: A Study of Three- and Two- Dimensional Mechanisms”, Soon Wan Kweon, Na Young Kang & Hyoung Jin Kim, BioResources , 2025, 20(1), p683. The dimensional absorbency properties of paper towels were studied, focusing on three- and two-dimensional absorption mechanisms. Key factors
Technical Abstracts
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