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Ethylene, the main raw material for polyethylene production, is a by-product produced by thermally decomposing naphtha and it contains a small amount of acetylene. The acetylene reacts as a permanent catalyst poison for the ethylene polymerization catalyst. In this study, we wanted to improve the acetylene conversion and the ethylene selectivity by selective hydrogenation of acetylene for removing acetylene contained in ethylene. Catalyst was prepared by loading nanosized gold (Au) and palladium (Pd) particles on support (Al2O3, TiO2). Deposition order Au and Pd particles was changed. The activity of the catalyst was investigated using a flow-typed fixed bed reactor under atmospheric pressure. Au and Pd particles deposited on TiO2 were oxidized to Au2O3 and PdO due to strong metal support interaction (SMSI). It was considered that the Au/Pd/Al2O3 catalyst was more active than the Pd/Au/Al2O3 catalyst due to the formation of the interface between Au particles and Pd particles (or support). But Pd/Au/Al2O3 catalyst is considered to have poor activity because Pd particles cover part of the interface between Au and the support. Au/Pd/Al2O3 catalyst showed the best catalytic activity, and acetylene conversion and ethylene selectivity were 100% and about 80% at 40 °C, respectively.

Styrenated phenol alkoxylates (SP-A) are prepared from styrenated phenols (SP) and ethylene oxide (EO) under a homogeneous base catalyst. However, to use EO that is difficult to handle, a high-pressure reaction device capable of reaction process control should be used. Additionally, the homogeneous base catalyst requires a neutralization process to remove the remaining catalyst after the reaction, and it is difficult to separate the catalysts and the product. Therefore, in this study, the separation of product and catalyst by using KOH/La₂O₃ catalyst was facilitated in the production of SP-A. Also, it was possible to produce SP-A under atmospheric pressure reaction conditions using EC. The mean molecular weight of SP-A varied depending on the reaction conditions, and the size of the mean molecular weight could be arbitrarily controlled by changing the reaction conditions.

Styrenated phenols (SPs) are usually synthesized by the reaction of styrene and phenol under acid catalysts. SPs with a high content of di-styrenated phenol (DSP) can be used to prepare styrenated phenol alkoxylate (SP-A). Therefore, in this study, a scale-up process for synthesizing SPs with high DSP content which can be used for synthesis of SP-A was studied. The solid catalyst used in this study was prepared by impregnation method. SO2-₄ was impregnated on a SO2-₄/ZrO₂ catalyst in an aqueous 1 M H₂SO₄ solution. The prepared catalysts were characterized by NH3-TPD. Catalytic activity was examined by measuring the conversion of phenol and styrene in a liquid-phase batch reactor. Almost 100% conversion of both phenol and styrene over 5-SO2-₄/ZrO₂ catalyst was obtained at a reaction temperature of 80 °C and a reaction time of 6 h. The amount of catalyst to the reactants was 2 wt%. Under the same reaction conditions, the selectivity of MSP, DSP, and TSP was 12.4%, 64.5%, and 23.1% respectively.

Styrenated phenol was prepared by an alkylation of phenol using NiCl2 and AlCl3 supported on silica gel. The conversion of phenol and styrene of alkylation reaction, and the selectivity of styrenated phenol were investigated. The Al · Ni/SiO2 Supported catalyst was used, the conversion of phenol was almost 100%. The product was in the form of a mixture of mono-styrenated phenol, di-styrenated phenol and tri-styrenated phenol. The styrenated phenol were selectivity of the varies depending on the reaction conditions.

Styrenated phenols (SPs) involving very small amount of unreacted phenol and high content of di-SP (DSP) were synthesized, which can be used to prepare SP alkoxylate. The solid catalyst was prepared by impregnation method. SO2-4 on SO2-4/MxOy catalyst was introduced from an aqueous 1M-H2SO4 solution. The catalysts were characterized by XRD patterns, and FT-IR spectra. The catalytic activity was examined by measuring conversion of phenol and styrene in a batch liquid-phase reactor. The concentration of phenol, styrene, and SPs were measured by GC with capillary column. The optimum synthesis conditions for concentration of sulfuric acid solution, catalyst amount of reactants, reaction temperature, and reaction time over SO2-4/ZrO2 catalyst were 15 wt%, 15 wt%, 100 °C, and 6 hr, respectively. At these conditions, conversion of both phenol and styrene were almost 100%, and the selectivity of DSP was 52.1%. On the other hand, the optimum synthesis conditions over SO2-4/TiO2 catalyst were 10 wt%, 5 wt%, 100 °C, and 1 hr, respectively, and conversion of both phenol and styrene were almost 100%, and the selectivity of DSP was 66.1%.

Hydrogenation of carbon dioxide (CO₂) into methanol (CH₃OH) was carried out in the CuO–ZnO based supported gold catalyst prepared by the co-precipitation method. When gold nanoparticles were added to the CuO–ZnO/Al2O₃ catalysts (CuO–ZnO/Au/Al₂O₃), the CO₂ conversion and CH₃OH yield were increased (two times higher than that of CuO–ZnO/Al₂O₃ catalyst) with increasing reaction pressure, but selectivity of CH3OH was decreased. The main reason of this result could suggest the importance gold-oxides interface in CH₃OH formation through hydrogenation of CO₂. Maximum selectivity and yield to CH₃OH over CuO–ZnO/Au/Al₂O₃ were obtained at 250°C and under 15–20 bars.

Styrenated phenols are usually synthesized by the reaction of styrene and phenol under acid catalysts. Styrenated phenol involving high content of di-styrenated phenol (DSP) was synthesized, which can be used to prepare styrenated phenol alkoxylate. The solid catalyst used in this study was prepared by impregnation method. SO4 2- on SO4 2-/ZrO2 catalyst was introduced from an aqueous 1M-H2SO4 solution. The catalysts were characterized by SEM images, XRD patterns, and FT-IR spectra. The catalytic activity was examined by measuring the conversion of phenol and styrene in a liquid-phase batch reactor. Almost 100% conversion of both phenol and styrene over 15-SO4 2-/ZrO2 catalyst were obtained at reaction temperature of 100 °C and reaction time of 6 hr. Amount of catalyst to the reactants was 15 wt%. At same reaction conditions, selectivity of MSP, DSP, and TSP were 23.6%, 52.1%, and 5.4%, respectively. It was known that the selectivity to DSP was increased as IR absorption peak of 1236 cm-1 corresponding to O–S–O bonds was increased.

− In this study, new platinum complexes were synthesized utilizing the ligand of a 2,2'-bispyrimidine (bpim), 2,2'bipyridine (bpy), 5,5'-dimethyl-2,2'-bipyridine (5,5-mebpy), 5'-bromo-2,2'-bipyridine (5-brbpy), 5,5'-dibromo-2,2'-bipyridine (5,5brbpy), 4,4'-dimethyl-2,2'-bipyridine (4,4-mebpy), 4, 4'dihexyl-2, 2'Bipyridine (4,4-hebpy), 1, 10'Phenanthroline (phen), 3, 4, 7, 8'tetramethyl-1, 10'Phenanthroline (3,4,7,8-phen). In order to determine chemical structure of Synthesized platinum complexes, H(C)-NMR, UV-vis and FT-IR were used and optical physics and chemical properties were measured PL. In the case of platinum complexes, wavelength has been identified 356~421 nm. Quantum efficiency in DMSO solution was appeared 0.05~0.46.

The reaction of platinum 5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)di-2,2'-bipyridine with 2,2'-bipyridine) PtCI2, (1,10-phenanthroline)PtC2 and (2,2'-bipyrimidine)PtC2: (2,2'-bipyridine)Pt[5,5"-(9,9-dioctyl-9H- fluorene-2,7-diyl)di-2,2'-bipyridine] (1) (2,2'-bipyrimi-dine)Pt[5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)di- 2,2'-bipyridine] (2) (1,10-Phenantroline)-Pt[5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)di-2,2'-bipyridine] (3). In the study, new platinum complex compounds were synthesized utilizing the ligand of a 5,5"-(9,9- dioctyl-9H-fluorene-2,7-diyl)di-2,2'-bipyridine). Each of the three complexes was obtained through the reaction carried out in this study. These complexes were analyzed using 1H(13C)-NMR, PL, and a UV-vis spectrophotometer. The maximum wavelengths of complexes 1, 2, and 3 appear at 519 nm, 375 nm, and 517 nm, respectively. The quantum yields of these complexes are in the range of 0.35-0.67.

In this study, titanium chips (TC) generated from industrial facilities was utilized as TiO2 support for hydrogenation of carbon dioxide (CO2) to methyl alcohol (CH3OH) over Cu-based catalysts. Nano-sized CuO and ZnO catalysts were deposited on TiO2 support using a co-precipitation (CP) method (CuO-ZnO/TiO2), where the thermal treatment of TC and the particle size of TiC2 are optimized on CO2 conversion under different reaction temperature and contact time. Direct hydrogenation of CO2 to CH3OH over CuO-ZnO/TiO2 catalysts was achieved and the maximum selectivity (22%) and yield (18.2%) of CH3OH were obtained in the range of reaction temperature 210-240 degrees C under the 30 bar. The selectivity was readily increased by increasing the flow rate, which does not affect much to the CO2 conversion and CH3OH yield.

Noble metal/metal oxide nanostructures are an efficient system in photocatalysis. Continuous and scalable production of advanced particle systems will be a requirement for commercial-scale deployment for many applications, including photocatalysis. In this work, Au/ZnO structures were synthesized in a continuous flow micro-reactor at room temperature and the detailed characteristics of the product indicate a specific cotton ball-like core-shell microstructure that showcases specific advantages compared to traditional batch synthesis methods. The formation pathway of the core-shell Au/ZnO structures is discussed with the pH-dependent speciation diagram, and photocatalytic activity was assessed under simulated sunlight, demonstrating the enhanced performance of the cotton ball-like Au/ZnO microstructures in photocatalytic dye degradation. This work describes the application of microreaction technology in the continuous production of metal/metal oxide photocatalysts.

The catalytic activity of a monolithic catalyst with nanosized Pt and Au particles on ZnO/Al2O3 (Pt-Au/ZnO/Al2O3/M) prepared by a wash-coat method was examined, specifically for toluene oxidation. Scanning electron microscopy image showed clearly the formation of a ZnO/Al2O3 layer on the monolith. Nanosized Pt-Au particles on ZnO/Al2O3/M with different sizes could be found in the Pt-Au/ZnO/Al2O3/M catalyst. The conversion of toluene decreased with increasing toluene concentration and was also largely affected by the feed flow rate. The Pt-Au/ZnO/Al2O3/M catalysts prepared in this work have almost the same activity (molecules of toluene per second) compared with a powder Pt-Au/ZnO/Al2O3 catalyst with the same loadings of Pt and Au components; thus this catalyst could be used in controlling air pollution with very low concentrations and high flow rate.

The reaction of platinum [Pt(4-(N,N-bis(piridyl)amino)stilbene)]Cl2 with 5,5"-(9,9-dioctyl-9H-fluorene- 2,7-diyl)di-2,2'-bipyridine, 2,2'-bipyridine, and 1,10-phenathroline affords the following complexes: [(4-(N,N-bis(piridyl)amino)stilbene)Pt(5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)di-2,2'-bipyridine)] (1), [(4-(N,N-bis(piridyl)amino)stilbene)Pt(2,2'-bipyridine)] (2), and [(4-(N,N-bis(piridyl)amino)stilbene) Pt(1,10-phenathroline)] (3). In this study, new platinum complex compounds were synthesized utilizing the ligand of a 4-(N,N-bis(piridyl)amino)stilbene system. These complexes were analyzed using a 1H(13C)-NMR, UV-vis and PL spectrophotometer. The maximum wavelengths of complexes 1, 2, and 3 appear at 409 nm, 410 nm, and 503 nm, respectively. The quantum yields of these complexes are 0.32-0.92.

The reaction of styrene with phenol using photoacid catalyst has been investigated. Upon irradiation with 450 nm light, protonated merocyanine photoacid converts into spiropyran form with releasing proton. The reaction of styrene with phenol has been conducted under irradiation with 450 nm light using merocyanine photoacid catalyst at room temperature in comparison with the results using some selected catalysts including or at the reaction temperature of .

In order to reutilize the spent metallic titanium chips, TiO2 photocatalysts were prepared using the self-propagating high-temperature synthesis (SHS) method, and were characterized by N2 gas adsorption, X-ray diffraction, and scanning electron microscope, particle size distribution. Also, their photocatalytic activities were evaluated using methylene blue as a model organic compound. It was confirmed that the crystal structure of TiO2 prepared by SHS method was relatively homogeneous powder of rutile type. Optimum conditions for photocatalytic degradation of methylene blue under UV-C irradiation were methylene blue 9.5 ppm in solution and at amount of TiO2 added of 0.02 g/L. In addition, it was found that the photocatalytic activity for methylene blue degradation over the prepared TiO2 particles was positively related with BET specific surface area.

The objective of this paper is to investigate the decomposition process of organic pollutants by liquid phase plasma. A bipolar pulsed power supply was used to generate discharges in the aqueous TiO2 nanoparticle dispersions. The applied voltage, pulse width, and frequency were 250 V, 5 micros, and 30 kHz, respectively. Properties of generated plasma were investigated by electrical and optical emission spectroscopy methods. The comparison of properties of the discharge operated with and without oxygen gas bubbling is shown. The results of electrical-discharge degradation of methylene blue showed that the decomposition rate increased with the TiO2 particle dosages. Addition of oxygen gas bubbles also increased the degradation rate of methylene blue.

Methyl alcohol is one of the basic intermediates in the chemical industry and is also being used as a fuel additive and as a clean burning fuel. In this study, conversion of carbon dioxide to methyl alcohol was investigated using catalytic chemical methods. Ceramic monoliths (M) with were used as catalyst supports. Monolith-supported CuO-ZnO catalysts were prepared by wash-coat method. The prepared catalysts were characterized by using ICP analysis, TEM images and XRD patterns. The catalytic activity for carbon dioxide hydrogenation to methyl alcohol was investigated using a flow-type reactor under various reaction temperature, pressure and contact time. In the preparation of monolith-supported CuO-ZnO catalysts by wash-coat method, proper concentration of precursors solution was 25.7% (w/v). The mixed crystal of CuO and ZnO was well supported on monolith. And it was known that more CuO component may be supported than ZnO component. Conversion of carbon dioxide was increased with increasing reaction temperature, but methyl alcohol selectivity was decreased. Optimum reaction temperature was about under 20 atm because of the reverse water gas shift reaction. Maximum yield of methyl alcohol over CuO-ZnO/M catalyst was 5.1 mol% at and 20 atm.

Autothermal reforming of propane was studied with respect to the addition of ceria to the supported Ni catalysts. Ni/Al2O3 catalysts showed a higher activity than Ni/MgAl catalysts. It was related to the ease of the catalyst reduction. Ni/Ce/MgAl and Ni/Ce/Al2O3 catalysts showed higher propane conversions and higher hydrogen yields. These were related to the particle size and the reducibilities of the catalysts. XRD analysis showed that the added CeO2 decreased the particle sizes of the supported Ni, but increased the amount of NiO on the catalyst surface, thus it improved the resistance to coking.

If the surface of the titanium chips (TC) was modified by thermal treatment under air atmosphere, it could be reused as catalyst support or photocatalytic materials. TC-supported CuO and ZnO catalysts were prepared by impregnation (IMP) method and co-precipitation (CP) method using cupric nitrate and zinc nitrate solution as precursors. Loading of CuO and ZnO on TC was 40.6wt% and 50.3wt%, respectively. The catalytic activity for CO2 hydrogenation was investigated using a flow-typed reactor under various pressures. Conversion of carbon dioxide to methyl alcohol over the CuO-ZnO/TC catalyst by CP and IMP methods were ca. 22% and ca. 10%, respectively. Conversion of carbon dioxide over CuO-ZnO/TC catalyst by CP method was increased with increasing reaction temperature in ranging of 15atm to 30 atm. Maximum selectivity and yield to methyl alcohol over CuO-ZnO/TC catalyst at 250°C were ca. 90% at 20 atm and ca. 18.2% at 30 atm, respectively.

The reaction of platinum(II) complexes of [Pt(bpy-R)Cl2] (R = H; 2,2’-bipyridine(bpy), R = 2(CH)3; 4,4’-dimethyl-2,2’-biypridine (DM-bpy), R = 4(CH3); 3,3’-5,5’-tertamethyl-2,2’-bipyridiyl (TM-bpy), (1-3) or [Pt(1,10-phen-R’)Cl2] (R’ = H; 1,10-phenanthroline(1,10-phen), R’= 4(CH3); 3,4,7,8-tetramethyl-1,10-phenanthroline(3,4,7,8-tetramethyl-1,10-phen) (4-5) with 1,4-bis(5'-2',2"-bipyridine)benzene(bpy-Ph-bpy) affords the following monomeric platinium(II) complexes: [Pt(bpy)(bpy-Ph-bpy)]2+(1), [Pt(DM-bpy)(bpy-Ph-bpy)](2), and [Pt(TM-bpy)(bpy-ph-bpy)]2+(3), [Pt(1,10-phenanthroline)(bpy-ph-bpy)]2+2+(4), [Pt(3,4,7,82+-tetramethyl-1,10-phen)(bpy-ph-bpy)]2+(5), respectively. These complexes were characterized by NMR, IR, UV/VIS and PL spectroscopy of the complexes were elucidated. The internal quantum yields of these platinum complexes are very high (0.13 ~ 0.99) and they emit light in the blue region (360 ~ 417 nm).

Mordenite and X- or Y-type faujasite were used to remove volatile organic compounds (VOCs) by adsorption at 25 °C. A microwave heating desorption system was applied for pollutant adsorbent regeneration. Studies were focused on the relationship between the adsorption and/or desorption behavior of selected VOCs (benzene, toluene, o-, m-, p-xylene, methanol, ethanol, iso-propanol, and methylethylketone: MEK) and the physicochemical properties of the zeolites (i.e. acidity, Si/Al ratio, crystal structure, pore structure, surface area, and pore volume) in this work. It was shown that the adsorption behavior of mordenite zeolites with low surface area depended on its crystal structure, while the faujasite zeolites with large surface area depended on the mesopore volume. Faujasite zeolites showed the greatest adsorption capacity for the selected VOCs. It was also shown that the mesopore volume with ink-bottle pores was advantageous for adsorption and, contrarily, the mesopore volume with cylindrical mesopores was advantageous for VOC desorption and zeolite regeneration. High efficiency desorption of VOCs was obtained using microwave heating. The highest microwave heating desorption efficiency was obtained with molecular sieve 13X due to the cylindrical pore structure.

Gold catalysts with loadings ranging from 0.5 to 7.0 wt% on a ZnO/Al2O3 support were prepared by the deposition–precipitation method (Au/ZnO/Al2O3) with ammonium bicarbonate as the precipitation agent and were evaluated for performance in CO oxidation. These catalysts were characterized by inductively coupled plasma-atom emission spectrometry, temperature programmed reduction, and scanning transmission electron microscopy. The catalytic activity for CO oxidation was measured using a flow reactor under atmospheric pressure. Catalytic activity was found to be strongly dependent on the reduction property of oxygen adsorbed on the gold surface, which related to gold particle size. Higher catalytic activity was found when the gold particles had an average diameter of 3–5 nm; in this range, gold catalysts were more active than the Pt/ZnO/Al2O3 catalyst in CO oxidation. Au/ZnO/Al2O3 catalyst with small amount of ZnO is more active than Au/Al2O3 catalyst due to higher dispersion of gold particles.

The Nanolayered TiO2 photocatalysts were prepared by thermal treatment of metallic titanium chips. Photocatalytic activity for methyl ethyl ketone (MEK) and toluene was investigated using a closed circulating system. The photocatalysts were characterized by SEM and XRD. Surface of the Ti chips changed to be rough with increase of treatment temperature, and severe oxidation over 900 degrees C resulted in TiO2 powder. Uniform TiO2 nanolayer was formed as a rutile type on the metallic chip. Photocatalytic decomposition of MEK over the TiO2 photocatalysts occurred efficiently by UV-C irradiation. The maximum activity for MEK was obtained over Ti Chip treated at 700 degrees C. It was known that the prepared photocatalyts could be applied to remove various VOCs.

The reaction of the iridium dimer [Ir(ppy)2(micro-Cl)]2 (ppy = 2-pyridiylphenyl) with bis(2,2'-bipyridin-5-yl) ethyne (bpy-C2-bpy), bis(2,2'-bipyridine)-butadiyne (bpy-C4-bpy), and bis(2,2'-bipyridin-5-yl-(Z)-hexa-3-ene-1,5-diyl) (bpy-C6H2-bpy) affords the following diiridium complexes: [ClO4]2 [(ppy)2Ir(bpy-C2-bpy)Ir(ppy)2] (1), [ClO4]2 [(ppy)2Ir(bpy-C4-bpy)Ir(ppy)2 (2), and [ClO4]2 [(ppy)2Ir(bpy-C6H6-bpy)Ir (ppy)2 (3), respectively. Herein, we describe the synthesis, characterization, and physical and electrochemical properties of the diiridium complexes in which the two iridium units are connected by a pi-conjugated nanowire bridge.

Bimetallic Pt-Au catalysts supported on ZnO/Al2O3 were prepared by incipient wetness impregnation (IW-IMP) method with different pretreatment conditions such as flow velocity, calcination temperature, and heating rate under H2 during the calcination procedure, and characterized by X-ray diffraction (XRD), CO chemisorption, and scanning transmission electron microscopy (STEM) equipped energy dispersive spectroscopy (EDS). Furthermore, catalytic activity for complete oxidation of toluene was measured using a flow reactor under atmospheric pressure. Finally, relationship between the particle sizes with pretreatment conditions and catalytic activity for toluene on the bimetallic Pt-Au catalysts was discussed. In these results, nanosized bimetallic Pt-Au particles on ZnO/Al2O3 could be prepared by IW-IMP method. Relationship between the Pt and Au particle size and activity for toluene oxidation was clearly observed.

As adsorption characteristics, breakthrough curve and adsorption capacity were investigated using a flow-typed fixed-bed adsorption system for single or binary component, mixed gas systems of toluene and methylethylketone (MEK) on activated carbon (AC) modified with phosphoric acid (PA). In the results, the amount of toluene and MEK adsorbed on the PA modified AC (PA/AC) was larger than that on the purified AC. The breakthrough curve of the key component (toluene) was sigmoidal in the binary components. However, the breakthrough curve of the non-key component (MEK) exhibited the roll-up phenomenon, which was entirely different from the single component adsorption process because of the competitive adsorption of the key component. After passing a stream of toluene over the MEK adsorbed PA/AC, almost all of the MEK was easily substituted with toluene and desorbed at 25 °C. Therefore, the roll-up of MEK was attributed to its lower adsorption intensity than toluene.

In this study, the photo-catalytic degradation of methylene blue in TiO2 particles-dispersed aqueous solution was carried out by irradiating microwave and UV light simultaneously. The results of photocatalytic degradation of methylene blue showed that the decomposition rate increased with the microwave intensity, UV intensity, TiO2 particle dosages and the circulating fluid velocity. From the result of microwave-assisted photo-catalytic degradation of methylene blue, decomposition rate were shown gradually increased according to the increase of pH. The photo-catalytic degradation rate constant obtained under simultaneous irradiation of microwave and UV light case was about 1.5 times higher than irradiation of UV light only case. This result suggests that there is a synergy effect when the constituent techniques are applied together and that the additional irradiation of microwave can play a very important role in photo-catalysis of organic water pollutants.

The bimetallic Pt–Au catalysts supported on ZnO/Al 2 O 3 with different Pt/Au molar ratios were prepared by impregnation (IMP) method using a mixed solution of Pt and Au precursor. These were characterized by X-ray diffraction (XRD), CO chemisorption, temperature programmed reduction (TPR), and transmission electron microscopy (TEM) equipped energy dispersive spectroscopy (EDS). Catalytic activity for complete oxidation of toluene was measured using a flow reactor under atmospheric pressure. In the results, the aggregation of Au particles depended on the molar ratio in the bimetallic Pt–Au catalyst, and Pt particles was well dispersed homogeneously even by the IMP method. The Pt 75 Au 25 and Pt 67 Au 33 catalysts concurrently coated with Pt and Au precursors by IMP method showed higher activity than monometallic Pt and Au catalyst for toluene oxidation. Also, in order of the catalytic activity for toluene was very good agreement compare with the TPR results. The Au particles might promote the toluene oxidation over the bimetallic catalyst concurrently coated with Pt and Au particles. Therefore, the size of Pt and Au particles and catalytic activity were confirmed to be correlated to molar ratio of Pt and Au loaded.

The selective catalytic reduction (SCR) of NO(x) with C3H6 was studied in the presence of oxygen. The double wash-coat monolith catalysts for SCR comprised a lower layer of Au (or Pt)/Al2O3 and a upper layer of zeolites. The catalytic performance of the double wash-coated catalyst was remarkably improved to broaden the temperature window. The Au and Pt particles were dispersed uniformly on the monolith with particle sizes range of 3 approximately 5 nm and 5 approximately 10 nm, respectively. The catalyst binders used were colloidal silica, potassium silicate and tetraethyl orthosilicate, and the best catalyst activity was achieved with using colloidal silica as a binder. The zeolites used for the catalyst upper layer were MCM-41, FER, Y5.3-Zeolite and ZSM5, among which the NH4-ZSM5-coated catalyst showed the highest activity. The experimental results confirmed the promising potential of the double wash-coat, monolith catalyst for SCR of NO(x) with C3H6 due to the effective combination of noble metal monolith catalyst with zeolite for the removal of NO(x) by SCR with hydrocarbons.

The alloy catalyst has been widely used because it will be able to improve the activity and selectivity of the single metal catalyst in a given chemical reaction. In this study, the preparation and characteristics of nanosized Pt and Au particles on alumina and their catalytic activity were described. Nanosized Pt–Au catalysts were prepared by impregnation (IMP) method and deposition (DP) method using alumina or ZnO/Al2O3 as support. The size of Pt and Au particles were observed by transmission electron microscopy (TEM), energy dispersive spectroscope (EDS), and X-ray diffraction (XRD). Catalytic activity for oxidation of methanol was measured using a flow reactor. It could be seen that the Pt particle size and dispersion in the alloy catalysts was rarely influenced by preparation methods and Au particles coated by deposition method were well dispersed. TEM images showed that Au particles were well dispersed in the Pt/Au/ZnO/Al2O3 catalyst of which Au particles was supported by deposition method. The catalytic activity for methanol are given in the order of Pt-Au[IMP]/ZnO/Al2O3 > Pt[IMP]/Au[DP]/ZnO/Al2O3 > Au[DP]/Pt[IMP]/ZnO/Al2O3 > Pt-Au[DP]/ZnO/Al2O3. Therefore, Au particle size was doing not play an important role in increasing the oxidation activity, but the Au particles may promote the methanol oxidation.

[ ] thin film were prepared in order to clarify optimum conditions for growth of the thin film depending upon process, and then by changing a number of deposition conditions and heat treatment conditions variously, structural and electrical characteristics were measured. Thereby, optimum process variables were derived. For the manufacture of the , Cu, In and Se were deposited in the named order. Among them, Cu and In were deposited by using the sputtering method in consideration of their adhesive force to the substrate, and the DC/RF power was controlled so that the composition of Cu and In might be 1:1, while the annealing temperature having an effect on the quality of the thin film was changed from to at intervals of .

Gold catalysts supported on alumina (Au/Al2O3) and zinc oxide/Al2O3 (Au/ZnO/Al2O3) were prepared by deposition-precipitation with ammonium bicarbonate, and were characterized by nitrogen gas adsorption, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and temperature programmed reduction. The effect of ZnO addition to the surface of Al2O3 on the catalytic activity of Al2O3-supported gold catalysts in carbon monoxide oxidation is discussed in detail. The additions of 4 wt% ZnO loading to Au/Al2O3 showed a higher degree of gold particle dispersion which resulted in higher catalytic activity with Au/ZnO/Al2O3 catalyst than with Au/Al2O3 catalyst.

The greenhouse effect of carbon dioxide (CO2) has been recognized as one of the most serious problems in the world. Conversion of CO2 to methyl alcohol (CH3OH) was studied using catalytic chemical methods. Honeycomb-typed monolith used as catalyst support was 400 cell/inch2. Pretreatment of the monolith surface was carried out by thermal treatment and acid treatment. Monolith-supported nanosized CuO-ZnO catalysts were prepared by wash-coat method. The prepared catalysts were characterized by using SEM, TEM, and XRD. The catalytic activity for CO2 hydrogenation to CH3OH was investigated using a flow-type reactor with varying reaction temperature, reaction pressure and contact time. Conversion of CO2 was increased with increasing reaction temperature, but selectivity to CH3OH was decreased. Optimum reaction temperature was about 250 degrees C under 20 atm. Because of the reverse water gas shift reaction.

The reaction of platinum [Pt(5,5-dmbpy)]Cl2 (5,5-dmbpy = 5,5'-dimethyl-2,2'-bipyridine) with 4,4'-dimethyl-2,2'-bipyridine (4,4-dmbpy), [Pt(dbbpy)]Cl2 (dbbpy = 4,4'-dibutyl-2,2'-bipyridine), [Pt(dpbpy)]Cl2 (dpbpy = 4,4'-dipentyl-2,2'-bipyridine) with 5,5'-dimethyl-2,2'-bipyridine (5,5-dmbpy) affords the following complexes: [(4,4-dmbpy)Pt(5,5-dmbpy)][PF6]2 (1) and [(dbbpy)Pt(5,5-dmbpy)][PF6]2 (2), [(dpbpy)Pt(5,5-dmbpy)][PF6]2 (3), [(5,5-dmbpy)Pt(5,5-dmbpy)][PF6]2 (4). This study was synthesized new platinum complex compounds utilizing ligand of 5,5'-Dimethyl-2,2'-dipyridyl System. To study the chemical composition was used 1H(13C)-NMR, UV-vis, Spectro photometer and Measurements about optical physics and chemical properties were measured to use spectrofluorometer. UV-vis absorption area was measured 310 nm to 383 nm and luminous wavelength was measured 390 nm to 419 nm.

Process variables for manufacturing CuInSe2 thin films were established in order to clarify optimum conditions for growth of the thin film depending upon process conditions (substrate temperature, sputtering pressure, DC/RF power), and then by changing the number of vapor deposition conditions and annealing conditions, structural and electrical characteristics were measured. Thereby, optimum process variables were derived. For the manufacture of CuInSe2, Cu, In and Se were vapor-deposited in the named order. Among them, Cu and In were vapor-deposited by using the sputtering method in consideration of their adhesive force to the substrate, and the DC/RF power was controlled so that the composition of Cu and In might be 1 : 1, while the surface temperature having an effect on the quality of the thin film was changed from 100 °C to 300 °C at intervals of 50 °C. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Selective catalytic reduction (SCR) among the approaches for alleviating NOx emission was much attracted. Zeolites have the advantage for adsorption of propene, and noble metal catalyst has the advantage for oxidation of NO to NO 2 . Pt (or Au)/Al 2 O 3 (or SiO 2 ) were used as the lower layer of double wash-coated monolith catalysts. Zeolites (H-mordenite or ZSM-5) were coated as the upper layer. The catalytic performance of the double wash-coated catalyst was, remarkably, improved. Also, temperature window was shifted to lower temperature and broadened. It was known that the combined noble metal monolith catalyst with zeolite was very effective in removing NOx by SCR with hydrocarbons.

Oxidation of ethylene was carried out over alumina-supported metal oxide catalysts and highly dispersed gold catalysts, respectively, under atmospheric pressure. The ethylene was completely oxidized to produce carbon dioxide and water with both metal oxide and gold catalysts. The activity of gold catalyst prepared by deposition method was much higher than that of supported metal oxide catalysts. Ultra-fine gold particles on Co3O4 were more active than on Al2O3. Fe2O3/Al2O3 and MnO2/Al2O3 catalysts were more active than MoO3/Al2O3 catalyst. The activity of the supported metal oxide catalysts was greatly enhanced by addition of gold particles. It was therefore considered that gold particles promote dissociative adsorption of oxygen and the adsorbed oxygen reacts with adsorbed ethylene on support adjacent to the active site.

PURPOSE To investigate the effects of visible light on human corneal epithelial cells and the impact of natural antioxidants on oxidative stress produced by overexposure to light. METHODS Light-emitting diodes with various wavelengths (410-830 nm) were used to irradiate human corneal epithelial cells, and cell viability was assessed. The production of reactive oxygen species (ROS) was analyzed using 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA). Ethyl alcohol (EtOH) extracts were prepared from mixtures of medicinal plants. After application of the EtOH extracts, the free radical scavenging activity was measured using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The induction of antioxidant enzymes including heme oxygenase-1 (HO-1), peroxiredoxin-1 (Prx-1), catalase (CAT), and superoxide dismutase-2 (SOD-2) by the extracts was evaluated by reverse transcription-polymerase chain reaction and Western blotting. The ability of the extracts to inhibit ROS was also analyzed using DCF-DA. RESULTS The viability of corneal epithelial cells was diminished after irradiation of blue light (above 10 J at 410 nm and 50 J at 480 nm). Reactive oxygen species production was induced by irradiation at 410 and 480 nm at doses of 5 J/cm(2) and higher. Ethyl alcohol extracts had potent radical scavenging activity. Application of the extracts not only increased the expression of HO-1, Prx-1, CAT, and SOD-2, but it also attenuated the ROS production induced by blue light in a dose-dependent manner. CONCLUSIONS Overexposure to blue light (410-480 nm) may have a harmful effect on human corneal epithelial cells compared with other visible light wavelengths. Medicinal plant extracts can have potent protective effects on blue light-induced oxidative stress.

Platinum complexes [Pt(bpy)Cl2](bpy: 2,2'-bipyridine) and [Pt(PT)Cl2](PT: 1,10-phenantroline) were reacted with 5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis(2,2'-bipyrine), bpy-spiro-bpy, to afford mono and diplatinium complexes: [(bpy)Pt(bpy-spiro-bpy)][PF6]2, [(bpy)Pt(bpy-spiro-bpy)Pt(bpy)])[PF6]4, and [(PT)Pt(bpy-spiro-bpy)])][PF6]2, which were characterized by NMR, UV/VIS, mass spectrum, and PL spectroscopy. They showed very high internal quantum yields (0.35-0.67) and emitted light in the blue region (473-520 nm). Herein, we describe the synthesis, characterization of the mono- and di-platinum complexes in detail.

We investigated the influence of a surfactant and reducing agent on the preparation of palladium nanoparticles, characterizing the prepared palladium nanoparticles by Transmission Electron Microscopy (TEM), and X-ray diffractometer (XRD). Colloidal palladium nanoparticles are prepared using PdCl2 as a precursor and polyvinylpyrrolidone (PVP) as a surfactant. In addition, hydrogen and sodium borohydride are used as reducing agents are used to characterize the prepared palladium nanoparticles. The concentrations of a precursor, a surfactant and its molecular weight affect the size of palladium nanoparticles, while the reducing agents influence the morphologies and structures of palladium nanoparticles.

The role of gold nanoparticles supported on ZnO in photocatalytic activity for dye degradation was investigated. To this end, gold nanoparticles supported on ZnO (Au–ZnO) were prepared using a simple co-precipitation method. The prepared nanocatalyst was characterized by high-resolution transmission electron microscopy, X-ray diffraction, temperature-programmed reduction, X-ray photoelectron spectroscopy, UV–Vis absorption, and photoluminescence. The photocatalytic activity of Au–ZnO was examined by the degradation of methylene blue in aqueous solution using a light source that has more than 95 % (i.e., energy) of emitted photons between 400 and 800 nm. Highly enhanced photocatalytic degradation of methylene blue in air at room temperature was observed from these Au–ZnO nanocatalysts with gold particle size ranging from 2 to 7 nm, with an average size of 3.8 nm. The observed rate constant for MB degradation on Au–ZnO was 0.0118/min compared with 0.0007/min for pure ZnO. Furthermore, the charge transfer pathway for the degradation of methylene blue in Au–ZnO is suggested.

The reaction of the [Pt(bpy-R)Cl2](bpy-R: R=H (2,2'-bipyridine); R=CH3 (4,4'-dimethyl-2,2'-biypridine (DM-bpy), 3,3'-5,5'-tertamethyl-2,2'-bipyridiyl (TM-bpy)) with 1,4-Bis(5'-2',2"-bipyridine)benzene (bpy-Ph-bpy) affords the following mono- and di-platinum complexes of [(bpy)Pt(bpy-Ph-bpy)][PF6]2 (1), [(bpy)Pt(bpy-Ph-bpy)Pt(bpy)])[PF6]4 (2), [(DM-bpy)Pt(bpy-Ph-bpy)])][PF6]2 (3), and [(TM-bpy)Pt(bpy-ph-bpy)[PF6]2 (4), respectively. These complexes were characterized by NMR, IR, UV/VIS, PL and cyclic voltammetry. The internal quantum yields of these platinum(II) complexes are very high (0.83-0.99) and these complexes emit light at deep blue regions (373-417 nm). The redox behavior of complexes 1 and 2 shows quasi-reversible process.

Nanosized TiO2 thin film on the substrate such as stainless steel plate and slide glass film were prepared by magnetron sputtering method, and these TiO2 thin films were characterized by field emission-scanning electron microscopy (FE-SEM). Photocatalytic activity for Methyl-ethyl-ketone (MEK) and acetaldehyde were measured using a closed circulating reaction system through the various ultra violet (UV) sources. From the results of SEM images, nanosized TiO2 thin film was uniformly coated on slide glass, ranging from 360 nm to 370 nm. Photocatalytic activity of MEK over TiO2 thin film on stainless steel plate did not occur by UV-A irradiation, but was efficiently decomposed by UV-B and UV-C. Also, acetaldehyde could be decomposed than MEK. The effect of sputtering conditions on their structure and photocatalytic activities were investigated in detail.

The photo-catalytic decomposition of rhodamine B was examined in aqueous nano TiO2 particles dispersions to assess effects of the microwave radiation assisted photo-catalytic process driven by UV radiation. The results of photo-catalytic degradation of rhodamine B showed that the decomposition rate increased with the microwave intensity, UV intensity, TiO2 particle dosages and the circulating fluid velocity. Addition of oxygen gas in the photo-catalytic degradation of rhodamine B increased the reaction rate. The effect of addition of H2O2 was not significant when photo-catalysis was used without additional microwave radiation or when microwave was irradiated without the use of photo-catalysts. When H2O2 was added under simultaneous use of photo-catalysis and microwave irradiation, however, considerably higher degradation reaction rates were observed. This study demonstrates that the microwave irradiation can play a very important role in photo-catalytic degradation.

Sn(CH3)4/Al2O3 prepared by the deposition of Sn(CH3)4 to alumina which was previously dehydroxylated by heating at 773–1223 K was found to be an active catalyst for the metathesis of alkenes. The catalytic activity greatly depended on the pretreatment temperature of the alumina and the amount of Sn(CH3)4 deposited.

Complete oxidation of ethylene was performed over supported noble metals or transition metals oxide catalysts and on monoliths under atmospheric pressure. Gold nanoparticles on Al2O3 or MxOy (M = Mo, Fe, Mn) were prepared by impregnation, coprecipitation, deposition, and dispersion methods. Nanoparticles prepared by impregnation method were irregular and very large above 25 nm, but those by coprecipitation and deposition method were uniformly nanosized at 4 ∼ 5 nm. The gold nanoparticle were outstandingly active in catalyzing oxidation of ethylene. The activity order of these catalysts with preparation methods was deposition > coprecipitation > impregnation, and Au/Co3O4 prepared by deposition method showed the best performance in ethylene oxidation. The addition of gold particles to MxOy/Al2O3 catalyst enhanced the ethylene oxidation activity significantly. The main role of the gold nanoparticles apparently was to promote dissociative adsorption of oxygen and to enhance the reoxidation of the catalyst.

Gold has rarely been utilized as a catalytic component because of its poor affinity to chemical species. It is however known that nanosized gold particles promote the dissociation of oxygen or hydrogen. In this study, alumina-supported metal oxide catalysts were prepared by impregnation method and applied to methanol oxidation. The dispersion form and size of the gold particles were observed by transmission electron microscopy (TEM). In the results, the maximum catalytic activity was obtained over the ZnO/Al2O3 catalyst, and the optimum loading was 4 wt%. Furthermore, nanosized gold particles at various loadings were added to ZnO/Al2O3 catalyst by deposition method. The gold particles on Au/ZnO/Al2O3 catalyst were well dispersed and the catalyst activity was remarkably increased compared to ZnO/Al2O3 catalyst. The role of gold particles in the increased catalytic activity is discussed and a possible mechanism is presented.

The interaction of butadiynediyl dimetal complexes [Fp*-C≡C-C≡C-M, Fp*=FeCp*(CO) 2 , M= Fp*, Rp, SiMe 3 , Rp= RuCp(CO) 2 ] with diiron nonacarbonyl, Fe 2 (CO) 9 , results in the formation of a mixture of products, as is also observed in the case of their interaction with organic acetylenes. Interesting polymetallic complexes, μ 3 -η 3 -propargylidene-ketene compounds, zwitterionic cluster compounds, and μ 3 -η 3 -propargyliden'e-cyclobutene compounds were isolated from the reaction mixtures and successfully characterized. The product distributions were found to be dependent on the metal fragment (M) at the other end of the C 4 rod. The results of the reaction are described.