The binary adsorption of nitrogen and carbon dioxide on zeolite-X was investigated. The adsorption equilibria of pure and binary systems were measured by static methods. In the binary system the equilibrium Selectivity of CO₂ over N₂ was very high: about 525 at a CO₂ mole fraction of 0.14 and a temperature of 15°C. Consequently, N₂ can be considered as inert when its mole fraction is less than 0.8. The ideal adsorbed-solution theory () predicted quite well the binary equilibrium data, while the extended Langmuir isotherm showed a great deviation. The dynamics of fixed-bed adsorption of CO₂-N₂ gas mixture (CO₂ 14.86 mole percent) was analyzed by the cell model under non-isothermal conditions, incorporated with binary adsorption equilibria, mass and heat transfer resistances and variation of gas velocity in the bed. The concentration and temperature history curves were determined and compared with the theoretical results. This cell-model with predicted well the dynamic behavior of the adsorption bed.

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Effective utilization of sludge-digestion gas (biogas) could be contributed to promotion of reducing greenhouse gasses and creation of a recycling society. However, the delay in the development of gas storage technology prevents the effective utilization. In this paper a new technology of biogas storage system is introduced, and the capability of the new system is evaluated.
First, we evaluated the adsorbent suitable for this system. High pressure adsorption equilibria of methane and carbon dioxide at 298K up to 6 MPa on various adsorbents were measured, and their adsorbents were evaluated in consideration of net dimensionless density [V/V] for this system. We found that the high packed density activated carbon made from the coconut cell is suitable for this system.
Secondly, we measured and modeling of the biogas storage capacity of activated carbon. Adsorption equilibria of binary mixture of methane and carbon dioxide at 298K and pressures to 1 MPa were also measured with the volumetric-flow desorption method and analyzed using an Ideal Adsorbed Solution Theory () which was one of the most general multi component adsorption equilibrium theories. The gave the good prediction of adsorption equilibrium of methane and carbon dioxide mixed gases that were primary components of biogas. Therefore, biogas storage capacities are probably predicted by the , and net biogas storage capacities of this technology are 13 times larger and 9 times larger than that of conventional compressed storage at 0.3 MPa and 0.7 MPa respectively.
Finally, influences of impurities in biogas on adsorption performance were evaluated. We conclude that the major cause of decreasing on adsorption performance was moisture in biogas, and the storage capacity was maintainable for a long period of time by removing moisture from biogas.

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5種類のメタンなどのガス吸着に適していると考えられる活性炭を用いて消化ガスの吸着貯蔵量の評価を行った．特に本研究では，消化ガス貯蔵における吸着熱の貯蔵量へ与える影響を明らかにし，活性炭の発熱による温度上昇を考慮した消化ガス吸着貯蔵量の評価を行うことを目的とした．まず，それぞれの活性炭について消化ガスの主成分であるメタン，二酸化炭素の単成分吸着等温線を測定し，Toth式および拡張Toth式で解析を行った．次に，求められたパラメーターを用いてIdeal Adsorbed Solution Theory（）でメタン，二酸化炭素混合ガスの2成分吸着量の予測を行った結果，実験値と誤差7%以内で一致した．また，を用いて消化ガスの吸着量を評価することが可能かを検討するため，実際の消化ガスの吸着量とにより求めた消化ガス組成のメタン，二酸化炭素混合ガスの吸着量を比較した結果，両者は8%以内で一致し，により消化ガスの任意の温度，組成，圧力での吸着量の予測が可能であることを確認した．さらに，貯蔵容器内を断熱状態と仮定し，吸着熱による貯蔵容器中心部の温度上昇を考慮した貯蔵量の計算方法を示し，従来の圧縮貯蔵との貯蔵効率の比較を行った結果，消化ガス貯蔵に適した活性炭を用いれば消化ガスを0.7 MPaで充填すると32 Kの温度上昇が予測されたが，圧縮貯蔵に比べ，0.3 MPaで16倍，0.6 MPaで10倍の貯蔵量を得られることを明らかにした．さらに，パイロット試験機を用いて実消化ガスを0.3, 0.5, 0.7 MPaで貯蔵した際の活性炭の温度上昇結果とを比較した結果，両者は3 K以内で一致した．

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The effects of adding Cr, Ni, Mo, V, Si and Mn on the low-alloy heat-resisting Mo-V steel of the base component 0·15% C, 0·8% Mo and 0·3% V were systematically studied.
The results obtained are as follows.
(1) S-curve is affected by Mo more remarkably than by V. When Mo and V are added together, then the noses of A₃ and A₁ transformation curves appear at about 770 and 700°C respectively and the bainite transformation at below about 575°C. By increasing Si, Cr and Mn, the beginning of A₃ transformation is retarded down to below about 700°C, and also that of bainite transformation down to below about 500°C, according to the decrease of temperature.
(2) By the X-ray analysis of the precipitated carbides extracted electrolytically from the isothermal transformed steels, M₂₃C₆, Fe₃C and VC are found in Mo-V steel, but only Fe₃C is found in plain Mo or V steel. No differences are found in the kinds of carbides of Mo-V steel even by changing Cr, Si, Mn etc.
(3) By adding Mo and V together, the hardness as quenched is far higher than by adding them independently of each other, and the hardness increases further by addin Cr, Mn, Si etc. respectively. These results are well understood according to the effects of the added elements on S-curves. The maximum Charpy impact value is obtained by tempering at temperatures between 730-750°C after quenching from 970°C.
(4) The tensile strengths of the Mo-V steels at room temperature are far higher than those of plain Mo or V steel and the ratios of the yield points to the tensile strengths are also high. As far as the variations of Cr, Si, Mn and Ni of the Mo-V steel are less than those described above, the required mechanical properties are obtainable by tempering at the adequate telmperatures between 730-750°C.
(5) By the results of creep-rupture tests of Mo-V steels at 500°C, the followings are confirmed; the effect of Si between 0·03-0·42% is not distinct; by adding Cr up to about 0·93%, the strengths are apt to decrease after long time; by those coataining about 0·45%Cr, the strengths are higher when Mn is lower; by those containing Cr and Ni up to the upper limit of specification the strengths are higher than those containing no Cr and no Ni.

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The Brunauer–Emmitt–Teller (BET) equation for multicomponent adsorption was derived using assumptions similar to those used in the derivation of the original BET equation. In addition to the assumptions used in the derivation of the original BET equation, the BET equation for mixture adsorption was obtained by assuming that multilayer adsorption in a given layer is independent of the identity of the molecule adsorbed beneath it in the previous layer. The adsorption and desorption processes were considered to be reactions and the expression for the equilibrium concentration on surface was obtained using the equilibrium constants of the reactions. The performance of the BET equation derived for mixtures was compared with that of the widely used extended Langmuir equation using some selected binary adsorption isotherm data shown in the literature. The performance of the BET equation derived in this work was better than that of the extended Langmuir equation in the prediction of adsorbed phase concentrations and adsorbed amounts for the binary systems considered in this work.

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-Freundlich モデルを用いて多成分系吸着のシミュレーションを行い, 全成分合計量の吸着平衡特性におよぼす初期濃度, 活性炭添加量, 濃度残存率の影響について検討した. 回分吸着等温線とカラム吸着等温線の差異と相互関係を明かにした上で, 初期濃度と基準吸着量により無次元化した吸着等温線がほぼ成立することを示し, 原水初期濃度の変化による回分吸着等温線の変化を予測するための実用的なモデルを誘導した.

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We investigate the adsorption of D₂/H₂ and HD/H₂ binary mixtures in carbon slit pores and carbon cylindrical pores using equilibrium molecular simulations, and determine the optimum pore size and topology for the quantum sieving of hydrogen isotopes at 77 K. We show that the grand canonical Monte Carlo method with the Feynman–Hibbs variational approach (FH-GCMC) can be used as an alternative to that with the rigorous Feynman path-integral formalism (PI-GCMC) for exploring quantum H₂ adsorption at 77 K. Further, we employ FH-GCMC to investigate the adsorption of D₂/H₂ and HD/H₂ binary mixtures at 77 K. We show that, under the separation conditions of adsorption/desorption cycling between 0.1 and 1 MPa at 77 K, the optimum pore topology for quantum sieving of hydrogen isotopes is a cylindrical pore, and the pore sizes that yield the largest recoverable adsorption amounts with high selectivity are 0.623 nm for D₂ and 0.625 nm for HD. We also demonstrate, by comparing the results with those from the binary-mixture FH-GCMC simulations, that the ideal adsorbed solution theory can effectively predict the selectivity of D₂ and HD over H₂ in nanopores at 77 K (below 1 MPa).

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活性炭等の多孔質吸着剤は揮発性有機化合物類（VOCs）の吸着除去や室内空気の清浄など様々な場面で
使用されているが，近年特に問題となっているppbレベルの極低濃度のVOCsの活性炭に対する吸着特性
はほとんど検討されていない．そこで，VOCsの気相濃度をガスクロマトグラフィー，ガスクロマトグラフ
ィー付質量分析計等で測定することで極低濃度の平衡吸着量を容易に測定できるヘッドスペースガスクロ
マトグラフィー（HSGC）法を用いてVOCsの活性炭に対する吸着平衡の測定を行い，その有効性を検討
した．まず，HSGC法と容量法による吸着等温線を比較し，HSGC法による吸着等温線の信頼性を確認し
た．次に3種類の活性炭，6種類の代表的なVOCsの幅広い濃度範囲での吸着等温線を測定し，Tothおよ
びDubinin-Radushkevichモデルで解析を行い，HSGC法において極低濃度吸着等温線の測定が可能で
あることを示した．さらに，HSGC法を用いれば容易に多成分系へ拡張が可能であるためジクロロメタン
-トリクロロエチレンの2成分吸着平衡を測定した結果，その吸着量は理想吸着相理論（ldealAdsorbed
SolutionTheory）による計算値とよく一致した．
したがって，HSGC法を用いれば容易に正確なVOCsの極低濃度の単成分および多成分系吸着等温線の
測定が可能であることを示した．

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An extended Dubinin-Radushkevich (DR) equation for predicting VOCs mixture adsorption equilibria on activated carbon has been proposed. Using Bering's mixture DR model within the framework of Myers-Prausnitz theory has derived a simple formulation of multicomponent adsorption equilibria. This equilibria equation provides following two advantages for reliable and rapid calculation of adsorption dynamics: (a)preservation of thermodynamic consistency (b)analytical form expression. This equation provides a satisfactory description of the adsorption equilibria of toluene+benzene vapors on activated carbon. Application for calculation of binary adsorption dynamics has been also successful.

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In this study, the hydrothermal conversion of FAU-type zeolites using an aqueous ammonia solution was investigated to understand the solid-phase transformation mechanism of the selective synthesis of target zeolites. In addition, the CO₂/N₂ separation ability of prepared materials was estimated from single-component adsorption isotherms by the ideal adsorbed solution theory. ABW and ANA-type zeolites were successfully synthesized from the FAU-type zeolites such as Li–LSX and Na–X, respectively, by a hydrothermal treatment using an aqueous ammonia solution. Li–LSX was completely converted into ABW by treating at a temperature above 150°C for 24 h, and ANA was mainly produced from Na–X at 250°C after treating for over 72 h. The pellet shape of the raw zeolites was maintained even after the hydrothermal treatment. Considering the transformation mechanisms, the results suggest that the transformation of the zeolite topology was caused by the ion exchange between the counter cation of the zeolite and ammonium ion in the solvent and the cation structure-directing effect under hydrothermal conditions. It can be concluded that the counter cations of the raw zeolites played an important role in the structural transformation. The simple synthesis method presented in this study enables the conversion of FAU-type zeolites, particularly X-type zeolite, into other types of zeolites without using strong bases, such as alkali hydroxides. In terms of the CO₂/N₂ separation ability, CO₂/N₂ selectivity for post-combustion CO₂ capture conditions drastically increased upon the hydrothermal treatment. In particular, the ABW-type zeolite exhibited extremely high CO₂/N₂ selectivity over 10000.

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用廃水に普遍的に存在するフミン質のような組成未知の有機物群に対して有機物全体の回分吸着等温線と分子量分布クロマトグラムを測定し, 理想吸着溶液理論 () から誘導した競合吸着モデル (-Freundlich モデル) を用いて解析することにより, 吸着強度と分子量の分布に基づいた組成分類と吸着特性を評価する方法を提案した. この解析評価方法は従来の評価手法に比べて解析作業が簡単化されており, 組成未知の混合有機物群の組成を定量的に把握し, 有機物群全体あるいはその分子量画分の平衡吸着容量特性を評価する上で有効であることを実証した. また, この解析評価方法を適用することにより, 凝集やオゾン酸化などの処理プロセスが有機物群の吸着特性に及ぼす影響を組成分布の変化に基づいて合理的に解釈できることを明らかにした.

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The multicomponent adsorption rate theory based on Dubinin-Astakhov model (MART-DA), which has been proposed in the previous report, is a practical model for predicting break-through curves of gas mixtures on activated carbon filter. In this paper, the MART-DA has been tested for abilities to predict total and component capacities reported for 13 sets of binary gas adsorption equilibria. Verified by the experimental data, it has been found that the MART-DA is successful in predicting adsorption equilibria of gas mixtures on activated carbon, and this precisions of prediction is comparable to that of the ideal adsorbed solution theory (). From the mathematical study, a multicomponent adsorption isotherm equation (for N⪰2) has been derived from the MART-DA. For pure gas adsorption (for N=1), this isotherm equation is theoretically identical with Dubinin-Astakhov equation. Moreover, it has been clarified that the adsorption/desorption kinetics calculated from MART-DA is equivalent to the linear driving force (LDF) approximated adsorption rate calculation.

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Patients with orthostatic dysregulation (OD)-associated disease may show autonomic disorders more frequently as compared with patients with other types of dizziness. However, the pathological mechanisms of OD remain unclear. We examined the cardiovascular autonomic function in dizzy patients with postural orthostatic tachycardia syndrome (POTS) or chronic orthostatic intolerance (OI) in order to evaluate the contribution of the autonomic disorders to the occurrence of dizziness. Heart rate variability analysis during the Schellong test showed that patients with POTS have hypo-parasympathetic function and relative hyper-sympathetic function, and that some patients with OI also have hypo-parasympathetic function. In our clinic, single therapy with a β1-blocker (Atenolol) for patients with POTS or single therapy with an a- agonist for patients with OI relieved orthostatic symptoms in 60% of the patients with POTS and OI. Further clinical studies on OD-associated disease to evaluate methods for accurate diagnosis and appropriate combined physical and pharmacotherapy may improve the outcomes in patients with OD-associated disease.

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The matrix solution behaviors of humic substances were studied by characterizing molecular weight distribution, hydrophilicity and others before and after batch tests of activated carbon treatment. Aquatic humic substances in peat water and pretreated peat water by alum coagulation were classified by size exclusion HPLC and Sep-Pak C-18 cartridge adsorption and extraction. The lower molecular weight and the less hydrophilic group has higher carbon adsorbability. Ideal adsorbed solution theory () using the Freundlich isotherm equation was used for the evaluation of adsorption isotherms of each classified groups of humic substances in batch adsorption experiments.

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Batch experiments on activated carbon adsorption of background organics of unknown composition were conducted. A few specific characteristics of the adsorption equilibria, such as the dependence of the overall isotherms on the overall initial concentrations, were demonstrated. Accordingly, a new approach was developed to mathematically describe the overall adsorption isotherms. This method consists of an overall adsorption isotherm expression derived from the ideal adsorbed solution theory () and a technique of fractionating the background organics into a multicomponent mixture in terms of the adsorptive strength described by the Freundlich parameters. Once the composition was determined by fitting the calculated overall isotherms to experimental data, the distribution of organics in both the liquid and the solid phases was calculated, and its relationship with the characteristic behavior of the overall adsorption isotherms was discussed.

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