eJournal MAPEKI (Masyarakat Peneliti Kayu Indonesia)
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Pengaruh Jenis Perekat terhadap Sifat Papan Partikel dari Campuran Limbah Vinir Sengon dan Bagas Sorgum
No full textLimbah industri perkayuan dan pertanian memiliki potensi untuk dijadikan bahan baku dalam pembuatan papan partikel. Penelitian ini bertujuan untuk mengetahui pengaruh jenis perekat terhadap sifat fisis dan mekanis papan partikel. Papan partikel dibuat dengan menggunakan perekat 10% urea formaldehida (UF), 10% fenol formaldehida (PF) dan 20% asam sitrat (CA). Komposisi campuran bahan baku partikel vinir sengon dan bagas sorgum yang digunakan dalam penelitian ini adalah 25:75 berdasarkan berat. Karakteristik papan partikel diuji secara fisis dan mekanis berdasarkan standar JIS A 5908:2003. Hasil penelitian ini menunjukkan bahwa sifat fisis terbaik dimiliki oleh papan yang dibuat dengan perekat CA. Sementara itu, sifat mekanis terbaik dimiliki oleh papan yang dibuat dengan perekat UF. Berdasarkan hasil penelitian, kadar air, pengembangan tebal, keteguhan patah, dan keteguhan rekat papan partikel telah memenuhi standar JIS A 5908:2003 untuk papan partikel
Recent Research Activities in Solid and Liquid Bioenergy from Lignocellulosic Biomass
No full textThe increase in energy demand, the lack of petroleum resources, and concern over global climate change have placed great emphasis on the development of new alternative energy technologies that can be used to replace fossil transportation fuels (Himmel et al. 2007; Labbe et al. 2008; Lee et al. 2009a,b,c; Teramoto et al. 2008, 2009). In this context, many countries have initiated extensive research and development programs for bioenergy. Bioenergy can be classified into three kinds of solid, liquid, and gas bioenergy. For the effective production and utilization of these three types of bioenergy, different technologies are required (Figure 1). Lignocellulosic biomass, such as wood and agricultural residues, are widely distributed and easily accessible at relatively low costs. Of these, wood has the benefit of having a higher energy content per volume, lower ash content, and nitrogen content. In this review, recent research trends and advances in bioenergy from lignocellulosic biomass will be summarized from the author’s point of view
Softening Behaviour of Indonesian Wood Species
No full textThis paper deals with softening behaviour measurements of Indonesian wood species by static bending tests. Wood samples with a size of 110mm (R) x 10mm (T) x 4mm (L) were bending tested in air-dry at 20°C and 65% relative humidity (RH), in water saturation at 20°C, and in water saturation at 80°C to know the decreasing of modulus of elasticity (MOE) and modulus of rupture (MOR) due to moisture content (MC) and both moisture content and temperature (MCT) changes. The wood samples represented Randu (Bombax ceiba. L) as the lowest specific gravity, i.e. 0.27 to Lamtoro (Leucaena glauca (Willd) Benth) as the highest specific gravity, i.e. 0.81. The three-point static bending test was carried out by a mechanical testing machine with a load capacity of 100kgf, loading deflection speed of 5mm/min, a span distance of 80mm at a room with a temperature of 20°C and 65% RH for air-dry wood samples, and that for wet wood samples were conducted in a water bath at 20°C (change in MC) and 80°C (change in MCT), respectively. MOE and MOR increased linearly with specific gravity regardless of wood species. On the other hand, maximum deflection did not correlate with specific gravity for any MCT conditions. The relative MOE and MOR which were calculated in wet 20°C to air-dry were affected from hardly to strongly depending on the wood species. Meanwhile, they decreased extremely when saturated in water at 80°C regardless of wood species. The relative MOE and MOR due to the change in MC or MCT was independent of specific gravity, as well. Furthermore, chemical compositions of the wood species were analysed to clarify the main factors that affected the decreasing of MOE and MOR due to MC and MCT changes. The results showed that the percentage of lignin and hemicelluloses in each wood played an important role in decreasing the static bending properties. Relative MOE and MOR decreased with increasing lignin and hemicellulose contents. It can be concluded that the hygrothermal properties of lignin and hemicelluloses significantly affect the changes of elastic and strength properties of wood in softening conditions
Extractive Content and Colour Properties of 11-Year-Old Superior Teak Wood
No full textThere is a lack of understanding about the properties of fast-growing teak trees harvested in young stage. Superior teak woods (11 years, 5 trees) grown in Pemalang FMU were assessed in vertical and radial positions for its extractive contents and colour properties. Extractions were conducted using a sequence of toluene, ethanol, and hot water. The color evaluation was performed using CIEL*a*b*’s chromaticity system. Toluene-, ethanol-, hot-water-, and total extractive contents ranged between 1.16~5.00%; 0.29~1,04%, and 0.98~2.35%, and 4.03~7.31%, respectively. For color properties, the brightness (L*), redness (a*), and yellowness (b*) indices ranged from 49.50~57.42, 6.08~10.81, and 20.47~25.74, espectively.Toluene- and total extractive contents were greater in heartwood than in sapwood, while the reverse occurred for the hot-water extractive content. Toluene- and total extractive contents were higher in outer heartwood than in inner heartwood. With regard to colour properties, L* and a* values were significantly differed between sapwood and heartwood. Vertical stem analysis of samples obtained at bottom, center, and top showed the toluene extractive content, total extractive content, and a* levels of center part of the tree were found to be lower than other parts. The L* were negatively correlated with extractive contents, with the highest correlation degree (-0.83**) being observed in the total extractive content in the heartwood. It is also noticed that superior teak wood wood was less darker and extractive contents than the heartwood control of a 72-year-old tree. Therefore, the properties measured in the present work might be related with natural durability of the woods
Peningkatan Kerapatan Kayu Samama Melalui Pre-kompresi Asam Sitrat (Density Improvement of Samama Wood by Pre-compression of Citric Acid)
No full textSamama wood (Anthocephalus macrophyllus (Roxb.) Havil.) is a potential fast-growing species of Sulawesi and Maluku. This study aimed to increase the density of the wood through citric acid pre-compression. The temperature/time pressing formula and the optimal concentration of citric acid for fixation were also determined. Water saturated samples of (5x5x4) cm3 (L = longitudinal x T = tangential x R = radial) were pre-compressed at 100 °C for one hour to reach drying set. Subsquently, the samples were soaked for 4 hours in a citric acid solution of 5% and 10% concentration, drained and wrapped in aluminum foil before re-pressed at 180 °C for 10, 20, 30, 40, 50, and 60 minutes. Fixation was measured by soaking the samples into water for 24 hours at room temperature. The results showed that the moisture contents at fiber saturation point ranged from 33.15-33.94%, with density of 0.46 g cm-3 and oven dry density of 0.37 g cm-3. The L, T, and R shrinkages were 0.18-0.20%, 4.13-4.14%, and 2.53-3.10%, respectively; while the T/R ratio was 1.33-1.63%. Pre-compression can only be done at a compression target of 25% with compression level of 19.57-20.01%. Pre-compression increased the oven dry density of 17.11-20.13% to 0.44-0.45 g cm-3. After thickness recovery, the weight of the oven dried samples increased by 1.79-2.72% at the 5% citric acid concentration and by 12.04-15.25% at the 10% citric acid concentration. Permanent fixation achieved at 180 °C for 50 minutes pressing time with 10% citric acid concentration
Analysis on Chemical Components of Woods to Predict Ethanol Production Values
No full textThis paper deals with analysis on chemical components of woods to predict ethanol production values. The aim is expected to give a reliable value of ethanol production, eliminating the effort needed to directly measure this ethanol production from each wood species. Since the data of wood chemical components is widely available, this result will be valuable in determining a potential use of a wood species as bio-ethanol feedstock. Saccharification and fermentation processes by enzymatic hydrolysis were applied for xylems derived from49 branch trees of Cibodas, 32 branch trees of Purwodadi, and 19 branch trees of Bali Botanical Gardens in Indonesia. Three major wood components were analysed, i.e. cellulose, hemicellulose, and lignin. The results show varied relationships between ethanol production and chemical components of wood. The content of cellulose in wood was not exactly related to its ethanol production. This trend was also occurred for the relationship between hemicellulose and ethanol production. However, lignin content in woods gave an expected trend where the less lignin content, the higher the ethanol production.Furthermore, the ratios of cellulose-hemicelluloses and cellulose-lignin have been quantified. The result showed that the celullose-lignin ratio can potentially be used to predict the value of ethanol production which is expressed by linear regression y = 0.0616x + 0.8341; where R² = 0.4127, x = ethanol production and y = cellulose-lignin ratio. Gymnostoma sumatranum with cellulose content of 43.8% and lignin content of 24.1% (celullose-lignin ratio of 1.8) has actual ethanol production of 12.1 mg/100mg wood meal, compared to 15.7 mg/100mg wood meal resulted from above equation. Therefore, by using its cellulose-lignin ratio, the woods having high ethanol production can be screened from literatures
Properties of Included Phloem in Teakwood
No full textIn some areas of Indonesia, the heartwood of teak tree (Tectona grandis L.f.) contains included phloem, which is categorized as defects. This paper characterized the colour and chemical properties of such abnormal wood. Three selected trees from Perhutani plantation, Randublatung region, were assessed. The heartwood colour properties were measured by CIELAB system. Result showed that the included phloem-containing heartwood (IPHW) was darker (L*), but less red (a*) and yellow (b*) compared to the adjacent normal heartwood (NHW). The lignin and ash contents were not significantly different in the wood radial direction. In contrast, the level of extractive contents were significantly different between sapwood and heartwood. The amount of ethanol-benzene extractive and solubility in 1% NaOH in the IPHW region were significantly higher than that in normal tissues. The analysis of extractive components using gas chromatography-mass spectrometry showed that the deoxylapachol and lapachol was highly marked in the IPWH region. The obtained results suggest that napthaquinone compounds were related to the protection against wood-destroying organisme attack
Anti-proliferative Activity of Some Oleanolic Acid Derivatives with Potent Topoisomerase Inhibitory Activity on B16 Melanoma Cells
No full textOur previous study included the semisynthetic reactions on oleanolic acid, a common wood-derived oleanane-type triterpene. Ten rationally designed derivatives of oleanolic acid were synthesized based on docking studies and tested for their topoisomerase I and IIα inhibitory activity. Semisynthetic reactions targeted C-3, C-12, C-13 and C-17. Some of these compounds act as dual inhibitors for both topoisomerase I and IIα giving new anticancer agents. The cytotoxic activity of these compounds on B16 melanoma cancer cells was evaluated. Results showed that most of these compounds have a higher cytotoxic activity on B16 melanoma cells
Beam-Column Timber Joint Connection Behavior Due to Nail and Modified-Washer Reinforcement Tests
No full textTimber connection capacity, in case of beam-column joint connection provides significant impact on the wooden building structures. Strength and stiffness of timber connections using reinforcement technique of wooden building structures have not been studied intensively. This paper studies the use of nails and modified-washer to improve wood connection’s performance. The experimental tests were conducted in the laboratory by comparing the partial connection between test specimen timber without reinforcement (standard type) and the reinforcement (PRP type). The testing was conducted based on partial connection beam-column joint test using Universal Testing Machine’s with a modified holder. Wood studied includes Meranti (Shorea spp.) and Mersawa (Anisoptera spp.). PRP type connection was using nails and modified-washer strengthening, and standard type connection was using a classic washer. Parameters studied were strength and stiffness of the connection, reviewed both: proportional limit load and ultimate limit load conditions. Result obtained from this research indicates that the use of nails and modified-washer make a positive contribution to improving the performance of the beam- column timber joint connections, in terms of strength capacity (both of proportional limit and ultimate limit loads) and stiffness capacity (displacement ductility ratio). Meranti beam-column timber joint is more brittle than Mersawa beam column timber joint, it has an impact on the results. PRP-type of Mersawa timber connection produces a higher ductility than the standard type, while the PRP-type of Meranti timber connection produces a similar ductility to the standard type
Sifat Fisis dan Mekanis Papan Partikel Hibrida dari Kayu Cepat Tumbuh dan Bambu dengan Perlakuan Perendaman Panas ( Physical and Mechanical Properties of Hybrid Particleboard from Fast Growing Wood Species and Bamboo with Heat Immersion Treatment)
Get PDFThe purpose of this study was to evaluate the physical and mechanical properties of hybrid particleboard made from combination of sengon wood (Falcataria moluccana), jabon wood (Anthocephalus cadamba), and betung bamboo (Dendrocalamus asper) with hot water immersion treatment. Pretreatment with hot water immersion was carried out in water bath at 80 ºC for 2 hours. The boards were made using urea formaldehyde (UF) adhesive with (30x30x0.9) cm3 size and 0.6 g cm-3 target density. Physical and mechanical properties of hybrid particleboards were evaluated based on JIS A 5908-2003 standard. The results showed that the combination treatment with bamboo particles can increase the mechanical properties and dimensional stability of the particleboards especially when combined with jabon particles. Hot water immersion treatment can improve the mechanical properties (MOE, MOR and IB) of hybrid particleboards. However, hot water immersion treatment decreased dimensional stability (thickness swelling and water absorption) of hybrid particleboards