日本エネルギー学会誌
検索
OR
閲覧
検索
93 巻 , 8 号
選択された号の論文の4件中1~4を表示しています
    • |<
    • <
    • 1
    • >
    • >|
総説
  • Michael J. ANTAL, Jr., Lieve M. HELSEN, Masato KOUZU, Jacques LÉDÉ, Yu ...
    93 巻 (2014) 8 号 p. 684-702
    公開日: 2014/08/29
    ジャーナル フリー
    The rules of thumb for developing thermochemical conversion technology are introduced together with the fundamental rules of thumb for thermochemical conversion, which is the basic idea for these technologies. The target technologies are, (a) metal-impregnated wood treatment by carbonization, (b) fast pyrolysis, (c) supercritical water gasification and, (d) advanced biodiesel production. They are presented in tables in terms of the rule of thumb and its benefit. We hope those who are considering introduction of these technologies will find this paper useful for their plant design and system development. It also should be noted that the scientific background supports the rules of thumb for each technology, and, thus, knowing the rules of thumb will provide insight into the fundamental science of the technology.
    抄録全体を表示
論文
  • Tetsuo UMEGAKI, Yasuhiro WATANUKI, Qiang XU, Yoshiyuki KOJIMA
    93 巻 (2014) 8 号 p. 703-709
    公開日: 2014/08/29
    ジャーナル フリー
    We study the effect of solvents on morphological and/or structural properties and catalytic activity of hollow nickel-silica composite spheres for hydrolytic dehydrogenation of ammonia borane. Nickel-silica composite shells were coated on polystyrene (PS) templates via sol-gel reaction with L(+)-arginine as the promoter of the sol-gel reaction followed or in parallel with the dissolution of the PS templates in the same medium to form hollow spheres. From the transmission electron microscopy (TEM) images, nickel-silica composite shells were formed for 1.5 h, and the surface roughness of the shells increases with the increase of aging time in methyl alcohol, while the shells were formed via the formation of aggregates of irregular shape in ethyl alcohol and 2-propyl alcohol. From the angle attenuated total reflectance infrared (ATR-IR) spectra, the order of dissolution rate of PS templates is 2-propyl alcohol > ethyl alcohol > methyl alcohol. These results indicate that the shells are formed before the dissolution of PS templates in methyl alcohol, while in ethyl alcohol and 2-propyl alcohol, nickel-silica composite shells was formed in parallel with dissolution of PS templates via the formation of aggregates of irregular shape. From the results of N2 adsorption/desorption isotherm analysis, the order of BET surface area is samples prepared in ethyl alcohol > methyl alcohol ≈ 2-propyl alcohol. The catalytic activity for hydrolytic dehydrogenation from aqueous NaBH4/NH3BH3 solution in the presence of the hollow spheres prepared in ethyl alcohol was much higher than those in the presence of the hollow spheres prepared in methyl alcohol and 2-propyl alcohol. Consequently, the solvents were mainly influenced in morphological homogeneity and BET surface area of hollow nickel-silica composite spheres, and these structural properties affected the catalytic activity.
    抄録全体を表示
  • Masahide YASUDA, Ryo KUROGI, Takayuki TOMO, Tsutomu SHIRAGAMI
    93 巻 (2014) 8 号 p. 710-715
    公開日: 2014/08/29
    ジャーナル フリー
    Biodiesel (BDF) has gained much attention as new sustainable energy alternative to petroleum-based fuels. In particular, BDF market has significantly increased in Europe to adhere energy and climate policies. Therefore, the increased BDF production requires new utilization of glycerol which is by product of BDF synthesis. We have focused on photocatalytic reforming using titanium oxide (TiO2) photocatalyst using glycerol as sacrificial agent (SaH). Recently we have found that SaH with all of the carbon attached oxygen atoms such as glycerol and methanol continued to serve as an electron source until their sacrificial ability was exhausted in photocatalyzed hydrogen evolution using a Pt-loaded TiO2 (Pt/TiO2) catalyst. Here we investigated the utilization of residual glycerol in BDF synthesis by photocatalytic reforming. BDF (methyl alkanoate) preparation by transesterification of commercially-available vegetable oil (136.5 g) was performed by heating with MeOH (23.8 g) in the presence of NaOH (0.485 g) at 61 ℃ for 2 h. After cooling, standard follow-up operation was performed as follows. The products were separated into a lower layer (Solution A) and an upper layer. The upper layer was washed with water and separated into a BDF layer and an aqueous washing solution (Solution B). Glycerol (10.4 g) was obtained from Solution A in 73.3% yield along with methanol (6.85 g). BDF (114.5 g) was isolated in 83.7% yield. Solution B contained methanol in 4.38 g. The residual glycerol and unreacted methanol were turned to hydrogen by TiO2-photocatalytic reforming of Solutions A and B using Pt/TiO2 (100 mg) in aqueous solution (150 mL) under irradiation by high-pressure mercury lamp. Hydrogen was evolved in 2.82 g and 0.28 g from Solutions A and B, respectively. The combustion energy (ΔH) of the evolved H2 corresponded to 100.8% based on the total ΔH of glycerol and methanol involved in Solutions A and B. Similar experiment was performed using pre-used vegetable oil. Hydrogen was recovered from Solutions A and B as 69.6% of ΔH. Presence of sodium alkanoate disturbed the hydrogen evolution.
    抄録全体を表示
技術論文
  • 中川 二彦, 満本 祐太
    93 巻 (2014) 8 号 p. 716-724
    公開日: 2014/08/29
    ジャーナル フリー
    東日本大震災後,日本ではCO2 排出量を抑制するとともに,原子力の依存度を下げるエネルギーシステムの構築が急務になっている。そのためには, 自然エネルギーの利用拡大と省エネルギーの推進を組み合わせたエネルギー供給と消費の方法を考える必要がある。そのひとつの例として,太陽光発電(以下,PVと記す)と電気自動車(以下,EVと記す)を用いたエネルギーシステムがある。しかし,従来のシステムにPVとEV を用いた場合,直流(以下,DC と記す)⇔交流(以下,AC と記す)変換損実が多いという課題がある。本研究では,PVとEV を組み合わせて, 住宅および工場などへ電力を給電するシステムおいて,PV の設置場所,面積およびEV の蓄電池容量などをエネルギーの消費に合わせて有効に利用するスマートPV & EV システムを提案した。また,PV で発電した電力のDC ⇔AC 変換ロスを大幅に低減する方法についても提案した。その結果,提案するシステムでは,PV 電力の総括使用効率を87%以上に向上できることを検証した。また,PV 電力の総括使用効率の向上に伴い,エネルギーシステムの経済性が向上されることを明らかにした。
    抄録全体を表示
    • |<
    • <
    • 1
    • >
    • >|
feedback
Top