Recent technologies in the production of chemicals and bio-materials products are focusing on lignocellulosic resources since it is the world’s most abundant material, low cost, as well as sustainable. Lignocellulosic biomass consists of three main compounds: cellulose, hemicellulose, and lignin. Productions of carbon fiber from lignin as its precursor are proposed to reduce the usage of fossil fuel based materials. However, the difficulties on recovering lignin from biomass are widely known. Therefore, several studies were conducted to explore possible technologies to isolate lignin from the complex lignocellulosic biomass in simple and minimal cost. One of the potential technologies is by using sub- and supercritical fluids. The polymer made of from phenylpropane units (p-coumaryl alcohol, coniferyl alcohol and sinapyl alcohol), the building block of lignin in plants can be converted to low molecular weight compounds using sub- and supercritical fluid technology with diverse applications including carbon fiber production. Hence, this paper aims to review on the lignin extraction from lignocellulosic biomass using sub- and supercritical fluid technology as precursor for carbon fiber production.

The utilization of renewable resource such as biomass in the production of green materials as an alternative to petrochemistry is increasing due to the depleting fossil resources and the increasing CO₂ emission. The present study focused on the use of tetraethoxysilane (TEOS) and dodecyltriethoxysilane (DTES) to modify surface of nanocellulose. One-pot method provides a facile and convenient route for the fabrication of hydrophobic nanocellulose-silica film as a renewable material for the water resistant packaging application. Morphological characterization of the hydrophobic nanocellulose-silica (NC-SiO₂-DTES) film showed well self-assembled DTES modified silica spherical nanoparticles with an average particle size of 126 nm over the nanocellulose film. The NCSiO₂-DTES film exhibited hydrophobic and superoleophilic properties simultaneously. It also performed chemical durability with an excellent hydrophobic property over a wide range of pH values. This approach is an alternative way to improve the hydrophobicity of nanocellulose films and can be applied in water resistant packaging.

本研究では，間接ガス化プロセスの１つであるBlue TowerプロセスによるBio-H₂燃料を対象に，燃料生産から消費に至るまでに一連のシステムについて，LCA（ライフサイクルアセスメント）指標によりそのシステム全体の性能評価を実施した。特に，ここでは，バイオマス原料を木くずとし，ガス化方式による燃料製造，及びBio-H₂燃料の利用用途として可能性の高い燃料電池を搭載した携帯電話に至るまでの一連のシステムを対象にした。本研究の特徴として，プラント側では，Bio-H₂燃料を精製動力の削減，H₂Sのような不純物の除去への影響について基礎実験を踏まえ検証し，アプリケーション側では，需要データの変動に対応するため電気二重層との複合システム構築を検討した。この結果，プラント側では新たな水素精製装置の導入による運転圧力低減と原料ガスからのCO₂分離を可能とし，一方で，アプリケーション側では電力負荷追随が十分に可能であるとの判断をした。この結果，携帯機器を含めたLCA指標においては，従来のリチウムイオン電池に比べ，最大で13.5％の削減効果が見込まれることが分かった。

This study focused on the synthesis of copper/carbon (Cu/C) composites through hydrothermal treatment of copper (II) acetate in the presence of xylose. The effect of the Cu content in the Cu/C composite on its electrochemical properties was investigated. The reduction of Cu²⁺ (CuO) to Cu¹⁺ (Cu2O) and Cu⁰ was observed during the hydrothermal reaction. The structure, surface morphology and metal dispersion of the Cu/C composites with and without carbonization treatment at 550 °C for 1 h were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy, respectively. The electrochemical properties of the Cu/C composites, in terms of cyclic voltammograms and galvanic charge/discharge, were investigated. The Cu/C composite formed with a 10 wt.% Cu loading by the one-step hydrothermal treatment at 190 °C for 24 h presented a good Cu dispersion on the carbon surface, and displayed a good charge transfer and high specific capacitance of up to 370 F/g.

Oil palm fronds (OPF) are potential resources for production of biomass-based chemicals such as furfural, levulinic acid, and 5-HMF due to its large abundance. Although there are various conventional methods for biomass conversion, they suffer from low yields as well as extreme reaction severity due to the usage of mineral acids as catalyst. A new method using subcritical alcohol can be an alternative. Hence, the aim of this study is to determine the feasibility of using subcritical alcohol for furfural production from OPF. The study will also determine the effect of reaction parameters such as reaction temperature, time, and types of alcohol towards the yield. From the study, it is concluded that high furfural yield can be achieved at milder temperature and moderate reaction time under subcritical conditions. The yield obtained is comparable with other conventional methods indicating that subcritical alcohol technology has the potential for furfural production.

酸素と水蒸気をガス化剤として用いる部分燃焼ガス化技術および水蒸気のみをガス化剤として用いる新たな高カロリーガス化によるガス化技術は，種々のバイオマス原料を900-1,000℃で完全にガス化し，煤やタールを極度に減じることができる技術の構築を目指して開発した。この技術の出口は，エンジン・タービンによる発電のほか，生成ガスが優れた組成の混合ガスであることからZn/Cu触媒を用いた化学合成によって液体バイオ燃料の製造が可能である。最初に開発した試作機「農林グリーン１号機」は2002年４月18日，さらに高カロリーガス化技術による「農林バイオマス３号機」は2004年に建設され稼働を開始した。2011年に農林水産省の補助により，廃材を利用したガス化，バイオメタノール生産（目標100リットル／時）が可能な大規模実用機が長崎市に建設され，技術実証に成功した。これらの大気を用いずに酸素や水蒸気のみをガス化剤として用いる本ガス化法の技術と試作機および生成ガスの特性について詳細に記述するとともに，従来の大気を用いたガス化技術との比較を行った。さらに，開発したガス化技術の利用の現状を鑑み，実用機の普及に向けた展望を議論した。

The environmental footprint for microalgae based biofuel can be reduced by coupling the microalgae cultivation with wastewater treatment. In the present study, the nutrients source for microalga Chlorella vulgaris was replaced by municipal wastewater from wastewater treatment plant located at USM Engineering Campus, Penang. All cultivation experiments were conducted in 5 L photobioreactors (PBRs) under indoor condition with illumination from artificial lights and compressed-air aeration. The growth performances of microalga C. vulgaris and nutrients uptake from wastewater were monitored throughout a 13-day cultivation period. The nutrients removal efficiency (NRE) for total nitrogen (TN) and total phosphorus (TP) by microalgae are 72.1 wt% and 89.7 wt%, respectively under the optimum cultivation conditions. Subsequently, microalgae biomass was collected by flocculation method, followed by extraction of lipid and transesterified to biodiesel. It was found that the biomass collected under optimum cultivation conditions achieved a maximum biomass dry weight density (N) of 0.76 g/L (or an equivalent biomass daily productivity, P of 58.6 mg/(L･d)).

バイオマスから得られるバイオマス水素は環境負荷の低い燃料として注目がされている。バイオマス水素の固体高分子型燃料電池（PEMFC）への応用するためには、バイオマス水素に含まれる不純物ガスの除去が必要である。したがって我々はこれまで，バイオマス水素の貯蔵と高純度化に水素吸蔵合金を用いることを提案してきた。水素吸蔵合金は、常温常圧の条件下においても，高圧タンクや液化水素よりも高密度に水素の吸収と放出ができるという特徴がある。さらに，水素吸蔵合金は水素のみを選択的に吸収放出するという性質があるため、これまでの我々の先行研究ではランタンリッチミッシュメタル合金を用いて、二酸化炭素や一酸化炭素などの不純物を含んだガスの不純物濃度を低下させることに成功している。現在，バイオマス水素はPSA（Pressure Swing Absorption）を組み合わせることで不純物は3％のメタンのみとなっている。本研究ではメタンの水素吸蔵合金の水素吸収性能や水素の回収率について評価したため報告する。

Viscosity of a solution is a convenient method to indirectly estimate the size of the solute in the solution. The current work investigates the viscosity of the solutions with different vegetable oil concentrations in two solvents, i.e., methyl ethyl ketone and tetrahydrofuran. The Huggins equation has been then applied to determine the intrinsic viscosity and the Huggins constant which are related to the size of the solute and the intermolecular interaction of solute in the solution, respectively. According to the results, intrinsic viscosities of vegetable oils increase following the order coconut oil (CO), sunflower oil (SF), and palm oil (PO). However, the intermolecular interaction is following the reverse order. This result is in accordance with our previous research on the relationship between molecular weight of triglyceride and its transesterification reaction rate in methyl ethyl ketone.

トレファクション処理による高性能木質燃料を製造するための小規模実証プラントを設計した。そのプラントでの連続製造を行う前に，予備試験としてペレット状のトレファクション燃料を試作し，これを市販の木質ペレットストーブでの燃焼試験に供した。燃料の主な性状（かさ密度，含水率，機械的耐久性等）はISO TS 17225-8の指標値を満たした。トレファクション燃料をペレットストーブで燃焼させると従来ペレット燃料に比べて着火時間が遅れは見られず，着火時の煙の発生が少ないことがわかった。

Recently, Rubber Seed Oil (RSO) has been considered as a promising potential oil source for biodiesel production. However, like other non-edible feedstocks, RSO contains a significant amount of high free fatty acids which affect the process of biodiesel production. In the present work, microwave-assisted esterification process was conducted as a pre-treatment step to reduce the high free fatty acid (FFA) content of RSO from 40.14% to less than 1%. Response surface methodology (RSM) involving central composite design (CCD) was employed in the design of experiments (DOE) and the optimization of esterification reaction. The optimum conditions were found at 60 °C, with methanol to oil molar ratio of 19.94:1, H₂SO₄ catalyst of 7.93 wt% and reaction time of 23 min. The result shows that methanol to oil molar ratio was the most influencing parameter towards the FFA reduction followed by temperature, whereas the catalyst loading and the reaction time both were observed to be insignificantly effective.

Liquefaction of oil palm trunk (OPT) in ethylene glycol and glycerol, with H₂SO₄ as a catalyst, at a temperature of 150 °C was conducted based on Design of Experiment (DoE) aided by software Stat-Ease Inc., Design-Expert^® Version 7. A 2^4-1 fractional factorial design was used. The results showed that factors such as types of solvents, percentage of H2SO4 catalyst and liquefaction time influenced the final liquefaction yield. Liquefaction of OPT in glycerol gave higher amount of liquefied yield. Besides, higher percentage of H₂SO₄ catalyst and longer liquefaction time also gave higher liquefaction yields.

Preparation, characteristic, and activity of CuO/γ-Al₂O₃ as re-generable SO₂ adsorbent have been studied. The model gas containing SO₂ of about 2,500 mg/m³ (700 mmHg, and 27 °C) was made to simulate the flue gas from combustion of algae biomass: Enteromorpha and Chlorella. Experiments were carried out in a tubular reactor electrically heated to maintain adsorption temperature of 300, 350, 400 or 450 °C. Amount of adsorbent was 1, 2, 4, or 8 g, and the gas flow rate was set at 1.21 L/min (700 mmHg, and 27 °C). Adsorbent with CuO content of about 7.5%-mass could adsorb SO₂ successfully and release the outlet gas with a SO₂ concentration to meet the national standard of SO₂ emission of 750 mg/Nm³. Naturally, the more amount of adsorbent in the reactor, the more complete conversion of SO₂ and the lower utilization of CuO.

本研究では，ルテニウム系触媒の担体として，メタケイ酸ナトリウムを原料とし，尿素を沈殿剤とした方法で球状シリカ粒子の調製を試みた。シリカ粒子の均一性は，メタケイ酸ナトリウムと尿素の比率により調整可能であり，そのサイズは20～1600 nmまで調整可能であることが確認された。ルテニウム担持触媒はこれらのシリカ粒子を担体として含浸法により調製したところ，ルテニウム溶液の濃度により担持されるルテニウム量が変化し，そのルテニウム量によって二酸化炭素水素化からのギ酸合成活性が変化することが確認された。一方，担持されるルテニウム量はシリカ担体の粒径が小さいほど増大するが，活性にはそれほど影響しないことが確認された。

メタノールは薬品，燃料，樹脂などを生産する上での重要な工業基礎原料であり，一般にメタンの水蒸気改質で得られるCOとH₂を触媒下で反応させることで合成する。しかし，このプロセスはエネルギー消費量が多く，直接合成法などの開発が望まれている。そこで，本研究ではメタンからのメタノール直接合成を目的として，水熱環境下でのフェントン反応による流通式メタン部分酸化試験を実施した。その際，反応温度T = 100～250℃，反応時間τ = 2～31 s，H₂O₂/CH₄ = 0.5～2.0を試験範囲とした。その結果，T = 200℃以下においてフェントン反応は無触媒条件よりも高いメタン転化率を示し，T = 200℃，τ = 31 s，H₂O₂/CH₄ = 2.0で最大値6.04%を得た。フェントン反応が反応活性種である・OHの生成を促したと考えられる。しかし，T = 250℃ではメタン転化率は急減し，無触媒条件よりも低い値であった。