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All Journal Communications in Science and Technology Journal of Applied Materials and Technology Molekul: Jurnal Ilmiah Kimia
Ohi, Hiroshi
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Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Engineering Materials Science & Nanotechnology Mechanical Engineering

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Enhancing dissolving pulp quality of mixed raw materials through pre-hydrolysis kraft-cooking: A study on Acacia crassicarpa and Terminalia catappa Sahan, Yusnimar; Rahmi, Sri Wahdini; Evelyn; Herman, Syamsu; Chairul; Khairat; Ohi, Hiroshi; Amri, Amun
Communications in Science and Technology Vol 9 No 2 (2024)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21924/cst.9.2.2024.1519

Abstract

Acacia crassicarpa wood is widely used in Indonesia as a raw material for dissolving pulp (DP) by the kraft-cooking process. Given that Indonesia has a rich variety and abundance of cellulose-rich wood, it is deemed crucial to research alternative raw materials, such as Terminalia catappa wood. As an alternative source of raw material, Terminalia catappa possesses excellent adaptability to various environmental conditions and is easy to grow everywhere. The current research sought to produce DP using the mixtures of materials from these two plant species as raw materials by pre-hydrolysis, kraft-cooking, and Elementary Chlorine Free (ECF) bleaching. The DP produced had ISO brightness > 88%, alpha-cellulose content > 94%, viscosity > 6.2 cP, and pentosan content of 2.54%. The DP quality traits have met the SNI 938:2017 standards for rayon-grade pulp. Acacia Crassicarpa and Terminalia Catappa are the prospective wood mixture for producing high-quality dissolving pulp via the kraft-cooking process.
From waste to value: Lapachol from teak wood waste as a green catalyst for sustainable soda cooking of Acacia and Eucalyptus Sari, Esty Octiana; Utami, Syelvia Putri; -, Evelyn; Nakagawa-Izumi, Akiko; Ohi, Hiroshi
Journal of Applied Materials and Technology Vol. 7 No. 1 (2025): September 2025
Publisher : Faculty of Engineering Universitas Riau and Applied Materials and Technology Society

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31258/Jamt.7.1.22-30

Abstract

The development of a sustainable catalyst as an alternative to synthetic anthraquinone (AQ) is urgently needed for a more efficient pulping process. This study investigates the potency of lapachol, a natural naphthoquinone isolated from teak (Tectona grandis) wood waste, as a catalyst in soda cooking of three industrially important hardwoods: Acacia crassicarpa, Eucalyptus pellita, and Eucalyptus globulus. Approximately 97.7% purity of lapachol was isolated and applied at 0.09% (on oven-dry wood). For comparison, the commercial synthetic additive, 2-Methylanthraquinone (2-MAQ) was also used at the same dosage.  Cooking experiments were conducted at 160°C under varying alkali dosages (23, 27, 31%) and times (4, 5, 6 h). The result revealed that the delignification performance was species-dependent: A. crassicarpa (S/V=0.74) was the hardest, while E. globulus (S/V=3.04) was the easiest to delignify. Notably, E. pellita (S/V=2.04) shows the greatest selectivity index. Lapachol shows the capability of enhancing delignification across the three wood species by decreasing the residual lignin by up to 5% in A. crassicarpa, 5% in E. Pellita, and 2% in E. globulus compared with soda cooking (control). Although the delignification is slightly lower than 2-MAQ, lapachol maintains pulp yields comparable to or higher than 2-MAQ. The selectivity index analysis confirmed that lapachol improved the balance between lignin removal and carbohydrate preservation, with the benefits most pronounced in E. globulus. These findings underscore lapachol as a promising sustainable pulping catalyst, offering the potential for impactful industry transformation through sustainable innovation.
Characteristics of Purified Lignin Obtained from Metroxylon Sagu Palm Fronds, Oil Palm Fronds, Cratoxylum arborescens, and Eucalyptus pellita via Soda-Methylanthraquinone Pulping Evelyn, Evelyn; Utami, Syelvia Putri; Yusnimar, Yusnimar; Fermi, Iwan; Chairul, Chairul; Ohi, Hiroshi
Molekul Vol 20 No 3 (2025)
Publisher : Universitas Jenderal Soedirman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.jm.2025.20.3.11016

Abstract

ABSTRACT. Lignin is a valuable material that can be obtained from the black liquor generated during dissolving pulp production from lignocellulosic materials. Lignin can be used to produce biopolymers, fuels, value-added chemicals, and other functional materials. This study investigates the isolation and characterization of lignin from four lignocellulosic biomass sources i.e. Metroxylon sagu palm fronds (SPF), oil palm fronds (OPF), Cratoxylum arborescens, and Eucalyptus pellita using environmentally friendly soda–methylanthraquinone (soda–MAQ, 160 ºC for 1.5 h) pulping followed by acid precipitation with hydrochloric acid (pH 2.0-2.5). The lignin yield varied among the materials (68.3-88.8%), with E. pellita showing the highest recovery. SEM analysis revealed distinct differences in lignin morphology, where E. pellita lignin exhibited a more condensed and homogeneous structure compared to the more fragmented forms from non-wood biomass. FT-IR spectra confirmed the presence of guaiacyl, syringyl, and hydroxyl phenol units in all samples. EDX analysis supported the natural lignin composition, especially in E. pellita, OPF, and C. arborescens. Among the four sources, lignin from E. pellita demonstrated the greatest potential for value-added applications, followed by C. arborescens and OPF. These findings provide valuable insight into lignin recovery from diverse biomass and its suitability for further bioproduct development. Keywords: Biomass, characterization, dissolving pulp, lignin, soda-methylanthraquinone
Co-Authors -, Evelyn Amun Amri Chairul Chairul Chairul Evelyn EVELYN EVELYN Fermi, Iwan Khairat Nakagawa-Izumi, Akiko Rahmi, Sri Wahdini Sari, Esty Octiana Syamsu Herman Syelvia Putri Utami Yusnimar Sahan