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The development of new amine solvents without the major drawbacks of conventional amines is crucial to industrial applications of CO2 capture. This paper presents a water-lean CO2 capture solvent having a low regeneration energy and low degradation. The water-lean solvent, K2Sol, is a sterically hindered diamine; because of the hindered amine site, K2Sol easily forms bicarbonate, resulting in a high absorption capacity. The minimum solvent regeneration energy is obtained using Gaussian process Bayesian optimization (GPBO) and bench-scale pilot plant experiments. GPBO finds the optimal solution using the input and output relationship of experiments; thus, expensive first-principle model construction can be avoided. According to the pilot plant experiment, the optimal regeneration energies of monoethanolamine (MEA) and K2Sol are 4.3 and 2.8 GJ/t CO2, respectively, indicating that K2Sol requires only 65% of the regeneration energy of MEA. Fewer than 30 experiments are required to find the optimal pilot plant operation for both the MEA and K2Sol experiments. We also describe the superior properties of K2Sol in terms of the CO2 loading, cyclic capacity, regeneration temperature, and degradation.

As part of an effort to prepare a refrigerant with zero ozone depletion potential (ODP) and with a low global warming potential (GWP), the catalytic dehydrofluorination of 1,1,1,2,3-tetrafluoropropane (HFC-245eb) is performed to produce 2,3,3,3-tetrafluoropropene (HFO-1234yf). Cr2O3 prepared by the sol-gel method (Cr2O3(SG)) exhibits good catalytic activity attributable to the formation of surface chromium oxyfluoride, which exhibits better catalytic activity with high-valent chromium and a larger fluorine content. The formation of chromium oxyfluoride from chromium oxide is achieved by in-situ fluorination in the early stage of dehydrofluorination, avoiding the conventional fluorination method using toxic HF.

Zn(OAc)2-catalyzed carbonylation and decarboxylation of glycerol and urea for the synthesis of glycidol were conducted at 150 °C, 2.7 kPa for 2 h and 170 °C, 2.0 kPa for 1.5 h, respectively. When the reaction conducted in a one-pot consecutive way, the yield of glycidol was 20%. However, when the formed zinc glycerolate (Zn(C3H6O3)) was filtered out after the carbonylation, the yield increased to 50% with respect to the amount of glycerol, whereas the yields of glycidol were very low when other zinc salts such as ZnCl2, ZnSO4 and Zn(NO3)2, were used as catalysts. The high catalytic activity of Zn(OAc)2 for this carbonylation and decarboxylation of glycerol and urea could be ascribed to the formation of Zn(NH3)x(OAc)2, which was determined from IR and TOF-SIMS studies.

Both DABCO (1,4-diazabicyclo[2.2.2]octane) and Merrifield resin-anchored DABCO ([p-DABCO]Cl), prepared from the reaction of DABCO and Merrifield resin, were found to exhibit high activities for the transesterification of dimethyl carbonate (DMC) with glycerol to produce glycerol carbonate (GLC). FT-IR and NMR spectroscopic results suggest that such a high transesterification activity of DABCO could be attributed to its superior ability to activate glycerol via a strong hydrogen bond formation between a hydroxyl group of glycerol and an amino group of DABCO. Meanwhile, the activation of glycerol by [p-DABCO]Cl proceeds mainly through the hydrogen bond interaction between a hydroxyl group or groups of glycerol and Cl− of [p-DABCO]Cl. The catalytic activity of [p-DABCO]Cl was maintained up to 5 reuses, demonstrating that [p-DABCO]Cl could be used as a recyclable heterogeneous catalyst.

Decarboxylation of glycerol carbonate (GLC) to produce 2,3-epoxy-1-propanol (glycidol) was conducted using various kinds of ionic liquids (ILs) as catalysts. ILs bearing an anion with medium hydrogen-bond basicity such as NO3- and I− exhibited the higher glycidol yields than those having an anion with low or strong hydrogen-bond. FT-IR spectroscopic analysis shows that both GLC and glycidol interact with anions of ILs through their hydroxyl groups. It was possible to improve the yield of glycidol when a zinc salt with a medium Lewis acidity was co-present along with an IL. The yield of glycidol was greatly increased up to 98% when the decarboxylation was conducted in the presence of a high-boiling aprotic solvent. Computational calculations on the mechanism using 1-butyl-3-methylimidazolium nitrate as a catalyst revealed that the first step is the NO3--assisted ring-opening of GLC followed by the ring closure, resulting in the formation of a 3-membered ring intermediate species.

Homogeneous zinc-catalyzed synthesis of glycerol carbonate from the reaction of glycerol with urea was investigated. Among the zinc-based catalysts tested, ZnCl2 showed the highest catalytic activity. Spectroscopic and elemental analyses of the zinc species, isolated from the reaction conducted in the presence of ZnCl2, revealed that Zn(NH3)Cl2 was generated first as an intermediate species, which in turn reacted with glycerol to produce zinc glycerolate, Zn(C3H6O3) and NH4Cl. The activity of Zn(C3H6O3) was considerably lower than that of ZnCl2, but the activity was greatly enhanced by the combined use of NH4Cl, implying that both Zn(C3H6O3) and NH4Cl were functioning as essential ingredients for the carbonylation of glycerol by urea. The formation of Zn(C3H6O3) was also observed when ZnBr2, ZnI2, ZnF2, Zn(NO3)2, Zn(CH3CO2)2, or ZnO was used as the catalyst.

The transesterification of dimethyl carbonate (DMC) with glycerol to produce glycerol carbonate was investigated in the presence of CaO under various reaction conditions. CaO was completely dissolved in the reaction mixture of glycerol and DMC in 5 min at 75 °C and at the molar ratio of glycerol/DMC/CaO of 1/2/0.01. The isolation and the characterization of the dissolved Ca species by means of TOF-SIMS, elemental analysis, and FT-IR revealed that an active species, Ca(C 3 H 7 O 3 )(OCO 2 CH 3 ) is generated from the interaction of CaO with glycerol and DMC. The mechanistic pathways to the formations of Ca(C 3 H 7 O 3 )(OCO 2 CH 3 ) and glycerol carbonate are discussed on the basis of experimental and spectroscopic results.

The conceptual design of a coal gasification system for the production of hydrogen is undertaken here using the PRO-II Simulation program. The operating conditions for the gasifier were tuned to between 1200 °C–1500 °C, 15 atm–30 atm and to a feed molar ratio of C:H 2 O:O 2 = 1:0.5–1:0.25–0.5. The refinery temperature and pressure were kept at 550 °Cand 24.5 atm. The syngas produced goes to water gas shift (WGS) reactors operated at 400 °C, 24 atm (HTS) and 250 °C, 23.5 atm (LTS). The production of hydrogen was found to be independent of the concentration of steam in the feed. However, when other operating conditions are constant, the hydrogen output changes dramatically with changes to the concentration of O 2 in the feed. The optimal operating conditions for the production of hydrogen by the gasification of Drayton coal were found to be: 1500 °C, 25 atm and a feed ratio C:H 2 O:O 2 = 1:0.58:0.43.

The solubility of carbon dioxide in room temperature ionic liquids (RTILs), dialkylimidazolium dialkylphosphates, was measured at 313–333 K and at pressures close to atmospheric pressure, from which Henry's law coefficients, standard Gibbs free energy, enthalpy, and entropy changes of solvation were derived. The CO2 solubility in the dialkylimidazolium dialkylphosphate was found to increase with increasing chain length of the alkyl groups on the cation and/or the anion as was similarly found in other RTILs. Among various dialkylimidazolium dialkylphosphates tested, 1-ethyl-3-methylimidazolium diethylphosphate ([EMIM][Et2PO4]) and 1-butyl-3-methylimidazolium dibutylphosphate ([BMIM][Bu2PO4]) exhibited the comparable or better capability of dissolving CO2 in comparison with that of [BMIM][BF4], but their absorption capacities were still lower than that of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][Tf2N]).

CF 3 CHFCF 2 OCH 2 CF 3 (1,1,2,3,3,3-hexafluoropropyl- 2 ′ , 2 ′ , 2 ′ -trifluoroethylether), one of the third generation CFC alternatives, was obtained in high yield and selectivity from the hydroalkoxylation reaction of hexafluoropropene with 2,2,2-trifluoroethanol conducted in the presence of a catalytic system consisting of a potassium salt and an ionic liquid, 1-butyl-3-methylimidazolium chloride ([BMIm]Cl). The formation of commonly observed olefinic side products in the hydroalkoxylation catalyzed by potassium salts was greatly reduced by the co-presence of [BMIm]Cl. Theoretical calculations and mechanistic studies suggested that potassium ion is largely responsible for the formation of olefinic side products.

An iso -octane fuel processor system with three different reaction stages, autothermal reforming (ATR) reaction of iso -octane, high temperature shift (HTS) and low temperature shift (LTS) reactions, was developed for applications in a fuel cell system. Catalytic properties of the prepared Ni/Fe/MgO/Al 2 O 3 and Pt–Ni/CeO 2 or molybdenum carbide catalysts were compared to those of commercial NiO/CaO/Al 2 O 3 and Cu/Zn/Al 2 O 3 catalysts for ATR and LTS reaction, respectively. It was found that the prepared catalysts formulations in the fuel processor system were more active than those of the commercial catalysts. As the exit gas of iso -octane ATR over the Ni/Fe/MgO/Al 2 O 3 catalyst was passed through Fe 3 O 4 –Cr 2 O 3 catalyst for HTS and Mo 2 C or Pt–Ni/CeO 2 catalyst for LTS reaction, the concentration of CO in hydrogen-rich stream was reduced to less than 2400 ppm. The results suggest that the iso -octane fuel processor system with prepared catalysts can be applied to PEMFC system when a preferential partial oxidation reaction is added to KIST iso -octane reformer system.

The tri-reforming reaction was carried out over NiO–YSZ–CeO2 catalyst to produce a synthesis gas from greenhouse gases like CH4 and CO2 contributing to the greenhouse effect. The NiO–YSZ–CeO2 catalysts were characterized by N2 physisorption, X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM) techniques. It was found that the tri-reforming reaction was more favorable than the dry reforming reaction for the production of synthesis gas. It was also observed that NiO–YSZ–CeO2 catalyst showed higher catalytic activity and stability than commercial Holder Topsoe (HT) and Imperial Chemical Industries (ICI) catalysts in the tri-reforming of CH4. The results suggest that the tri-reforming process can be applied to the production of high-valued chemicals and the fuel processor of solid oxide fuel cell (SOFC) and molten carbonate fuel cell (MCFC) systems.

The performance and operation results of the reformer that supplies synthesis gases to a 100 kW class molten carbonate fuel cell are reported. A CH 4 conversion ratio of 95.6%, a CO conversion ratio of 31.2%, a reforming reaction temperature of 745 °C and a produced hydrogen rate of 70.7 Nm 3 h −1 are obtained from a comparison of post gas analysis and theoretical estimation of thermodynamics at 87.6 h. To calculate the efficiency, the Cycle-Tempo 5.0 program is used. The thermal efficiency of the designed system is 61.1% and the real thermal efficiency of the system is 44.5% at 108 h. The low thermal efficiency is mainly attributed to supplying excess fuel to meet the outlet temperature of the reforming reactors. In the present system, the outlet temperature of the reforming reactors appears to be below the temperature required at the stack of molten carbonate fuel cell (MCFC), that is, over 580 °C. In order to maintain the outlet temperature of the reforming reactor over 580 °C, it is necessary to heat the reformed gases at the convection zone of combustion gases. For higher thermal efficiency, the combustion space and the excess fuel should be reduced until reaching minimum temperature of the surface of reforming tube, at which point has no influence on the CH 4 conversion ratio.

A series of ionic liquid-based zinc tetrahalide complexes were synthesized and their effects in the coupling reactions of ethylene oxide (EO) and carbon dioxide to produce ethylene carbonate (EC) were evaluated. The zinc tetrahalide complexes displayed high catalytic activities for the coupling reaction, but were found to cause a severe decomposition of EC during the vacuum-distillation of the product mixture. Among the various factors affecting the EC decomposition, the concentration of zinc tetrahalide species was most responsible for the decomposition: the lower the concentration, the lesser the decomposition. The addition of an imidazolium or ammonium halide was effective for enhancing the activity of the zinc tetrahalide complex while having only a minor effect on the decomposition rate. The optimum catalyst composition was discussed for producing EC feasibly with minimized product decomposition.

Phosphine adducts of zinc(II) halides, ZnX2L2 (X = Cl, Br, I; L = PMe2Ph, PEt3, PBu3, PPh3, PCy3), prepared by the reaction of ZnX2 with two equivalents of corresponding phosphines, showed high activities for the coupling reaction of CO2 and ethylene oxide to produce ethylene carbonate. The catalytic activity of ZnX2L2 was hardly affected by the nucleophilicity of the phosphine ligands, with the exception of ZnX2(PCy3)2, but depended strongly on the nature of halide ligands. An active species containing ethoxyphosphonium ligands, Zn3Br6[μ-OCH2CH2-P(C6H5)3]3, was isolated and characterized by X-ray crystallography, elemental analysis, and NMR spectroscopy. The mechanistic pathway for the formation of active species and cyclic carbonates is discussed.

To examine whether acid treatment of a non-graphitizing hard carbon influences positively or negatively its electrochemical anodic performance, this study reports the effects of sulfuric acid treatment on the microstructural changes and electrochemical performance of PAN-based hard carbons prepared at various temperatures. It was found that PAN-based hard carbons heat treated at 900 °C (TAN9) exhibit an increased reversible capacity by up to ∼20% and a decreased irreversible capacity by up to ∼8% following the sulfuric acid treatment (TAN9S series). Since small changes in microstructure, except for slight reductions in surface area and crystallite size (La) value, were observed after sulfuric acid treatment, it was speculated that the capacity responses of samples in series TAN9S were due to the introduction of new functional groups such as SO3H and SO4H. As the newly introduced functional groups are strong acids but their conjugates ( SO 3 - and SO 4 - ) are weak bases, those conjugates were thus considered to be able to react with Li+ ion relatively weakly and reversibly. For PAN-based hard carbons heat treated at 1100 °C (TAN11), there were much smaller changes, as compared with series TAN9S samples, in surface chemistry and microstructure by sulfuric acid treatment. Consequently, we observed an analogous but smaller influence of sulfuric acid oxidation on electrochemical performance. The samples from series TAN11S exhibited very stable cycling behavior. It was suggested that the acidity/basicity of surface functional groups may be an influential factor for improving the electrochemical performance of hard carbon-based anodic materials for lithium ion batteries.

The partial oxidation (POX) reforming process of gasoline is an attractive option for the applications to fuel cell-powered vehicles. As a part of the development of a gasoline fuel processor, various supported transition metal formulations for the POX-reforming of iso -octane were investigated. Many of the tested catalysts displayed reasonably good activity towards the POX-reforming of iso -octane. Some catalyst formulations showed better activity than a commercial ICI catalyst under the tested conditions. It was found that catalytic formulations of Ni/M/MgO/Al 2 O 3 were more active than the other catalyst formulations in the POX-reforming of iso -octane. Especially, Ni/Fe/MgO/Al 2 O 3 catalyst with high stability in POX-reforming of iso -octane ( C s iso -octane containing sulfur ( C s =100 ppm), even though none of the systems was found to be completely sulfur resistant. It was suggested that Ni/Fe/MgO/Al 2 O 3 catalyst may be used as an alternative option in place of the commercial ICI reforming catalyst for fuel cell-powered vehicles.

Various tin complexes including dibutyltin oxide and dibutyltin diacetate were tested for their activities in the transesterification between dimethyl carbonate (DMC) and phenol to produce diphenyl carbonate (DPC). The activities of tin complexes were significantly enhanced by the co-presence of alkyl or arylsulfonic acid, possibly due to the in situ formation of sulfonate-bonded tin complexes. Highly active triflate-bonded tin species, [Bu 2 Sn(OH)(OTf)] 2 and [Bu 2 Sn(OAc)(OTf)] 2 , were isolated from the reaction of triflic acid with dibutyltin oxide and dibutyltin diacetate, and characterized by single crystal X-ray diffraction study.

The purpose of this study was to evaluate the stabilization of salmon calcitonin (sCT) by PEGylation in nasal mucosa. Degradation of native sCT in the homogenates of rat nasal mucosa was investigated by matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF MS). The initial cleavage of sCT was due to tryptic-like endopeptidase activity, and the subsequent degradation followed the sequential pattern of aminopeptidase activity. To prepare PEGylated sCT resistantto theproteolytic degradation, thelysine residues susceptible totryptic activity were selectively PEGylated by controlling reaction pH. The PEGylated sCT showed strong resistance against enzymatic degradation in rat nasal mucosa, with 56-fold prolonged half-life compared with that of native sCT. In the MALDI-TOF MS spectrum, the PEGylated sCT did not show any degradation peak for incubation of 120 min in the homogenates of rat nasal mucosa. The improved stability may be responsible for en- hancing nasal absorption of PEGylated sCT. 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 93:256-261, 2004

The purpose of this research was to assess the acylation reactions of peptides, salmon calcitonin (sCT), human parathyroid hormone 1-34 (hPTH1-34) and leuprolide, in poly(lactic-co-glycolic acid) (PLGA) microspheres. Capillary electrophoresis (CE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) were used for determining and monitoring peptide acylation and quantitating acylation products in the degrading PLGA microspheres. In the degrading PLGA microspheres of sCT and hPTH1-34, the acylation products were observed and determined to be adducts with glycolic acid units from degradable PLGA polymer by MALDI-TOF MS. In the microsphere of leuprolide, however, the acylation product was not observed even after 28 days of incubation at the release medium, which represents the different stabilities among peptides according to the primary structure. As the leuprolide contains tyrosine and serine having hydroxyl group of nucleophilic amino acids, the acylation reaction of peptide is shown to be mainly due to the primary amino groups of N-terminus or lysine residue. The complementary use of CE and MALDI-TOF MS will be useful for searching the counter measures as well as determining the peptide acylation in the manufactured formulations on the market.

Hydrogen generation for fuel-cell powered vehicles by reforming technologies from various fuels has gained much attention recently. The successful development of a fuel cell-powered vehicle is dependent on the developement of a fuel processor. As part of the development of gasoline reforming system for intergration with PEM fuel cell, we investigated POX reforming (or autothermal reforming, ATR) reaction of iso-octane with/without 100 ppm sulfur and of reformulated naphta over a commercial naphta reforming (NRC) catalyst. We also investigated high temperature water gas shift (HTS) reaction over Fe3O4–Cr2O3 catalysts and low temperature shift (LTS) reaction over Cu/ZnO/Al2O3 catalyst to remove CO from the hydrogen-rich stream produced by fuel processing section. The H2 and CO concentrations from the POX reforming of iso-octane over the NRC catalyst increased with increasing reaction temperature, while that of CO2 and CH4 decreased. It was found that the NRC catalyst was prone to be poisoned by sulfur contained in gasoline, but there is no coke deposition at 700°C under the tested conditions. We confirmed that the concentration of CO in hydrogen-rich stream is reduced to

CHF 2 OCH 3 (HFE-152a), an important starting material for synthesizing various C 2 hydrofluoroethers and a prospective alternative to CH 3 CF 2 Cl (HCFC-142b), has been found to be effectively produced from the reaction of CHF 2 Cl (HCFC-22) with alkali metal carbonates in methanol. Some alkali metal carbonates induce selective production of CHF 2 OCH 3 with a small amount of CH(OCH 3 ) 3 , a major side product. Activities of alkali metal carbonates for producing CHF 2 OCH 3 are in the order of K 2 CO 3 >Na 2 CO 3 >Li 2 CO 3 , suggesting that the solubility and ionization tendency of alkali metal carbonate in methanol play important roles in the reaction.

Various factors affecting the oxidative carbonylation of aromatic amines were investigated in the presence of a catalyst system comprising SeO2 and alkali metal carbonate. An active catalyst, K2SeO3 was obtained from the reaction of SeO2 and K2CO3 in methanol and the activity was tested. The effects of added alkali metal salts, solvents, aromatic amine substrates, molar ratio of aniline to catalyst, temperature, and pressure on the catalytic activity were studied. The activation energy of the carbonylation of aniline was evaluated as 17.0 kcal/mol. The highest turnover frequency was found to be 2082/h at aniline/catalyst=12,800. A plausible mechanism for the carbonylation of aniline to diphenyl urea and phenyl carbamate has also been proposed.

The influences of added alkali metal nitrates and nitrites on the performances of ruthenium catalysts in the liquid phase ring hydrogenation of 4,4′-methylenedianiline (MDA) and 1,4-phenylenediamine (PDA) have been examined. Sodium nitrate and sodium nitrite were shown to be the most effective promoters in enhancing the catalytic activity and in suppressing the formation of by-products. The effects of various solvents and the added water on the hydrogenation activity have also been investigated. The promoting effects of sodium nitrate and sodium nitrite were considerably enhanced in the presence of small amounts of water. XRD patterns of the Ru/Al2O3 catalyst sample obtained from the reaction performed in the presence of NaNO3 or NaNO2 revealed that the sodium aluminate (NaAlO2) phase appears indicating that the cations of metal salts are interacting with the supporting material. An active species, NaOCH(CH3)2, was isolated and identified by spectroscopic and elemental analyses.

A high-performance liquid chromatographic method was developed for the determination of a new non-narcotic analgesic, DA-5018 (I), in rat plasma, urine and bile samples, using propranolol for plasma samples and protriptyline for urine and bile samples as internal standards. The method involved extraction followed by injection of 100 μl of the aqueous layer onto a C18 reversed-phase column. The mobile phases were 5 mM methanesulfonic acid with 10 mM NaH2PO4 (pH 2.5)-acetonitrile, 70:30 (v/v) for plasma samples and 75:25 (v/v) for urine and bile samples. The flow-rates were 1.0 ml/min for plasma samples and 1.2 ml/min for urine and bile samples. The column effluent was monitored by a fluorescence detector with an excitation wavelength of 270 nm and an emission wavelength of 330 nm. The retention time for I was 4.8 min in plasma samples and 10.0 min in urine and bile samples. The detection limits for I in rat plasma, urine and bile were 20, 100 and 100 ng/ml, respectively. There was no interference from endogenous substances.

The use of imidazolium-based ionic liquids as promoters was found to be highly effective for the hydrolysis reaction of CF3CH2Cl with aqueous potassium acetate to produce 2,2,2-trifluoroethanol (TFE). Among ionic liquids tested, 1-butyl-3-methylimidazolium chloride ([bmim]Cl) showed the highest yield of TFE, over 90%, which is almost two times higher than that obtained in the absence of an ionic liquid. The integrity of imidazolium salt was maintained during the reaction, which was confirmed from the recycling studies and 1H NMR spectroscopy.

A nonlinear self-tuning regulator for controlling the pH value of weak acid streams by a strong base is proposed. The nonlinear state equations describing the neutralization process are transformed so that we can estimate the unknown parameters, the concentration and the dissociation constant of the influent weak acid, via the recursive least squares method with a variable forgetting factor. Then we apply the one-step-ahead control law. Simulation results show that the regulator provides good performance for realistic situations such as multicomponent weak acid and strong base systems.