• Korean Chemical Engineering Research
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• v.53 no.1
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• pp.121-126
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• 2015

The objective of this study is to evaluate the catalytic potential of the porous material prepared from water treatment sludge. The textural properties of the catalyst were studied using $N_2$ adsorption and desorption isotherms, scanning electron microscope, and X-ray diffraction. The pellet-type catalyst prepared using water treatment sludge is determined to be a material that contains mesopores as well as micropores. The specific surface area of the catalyst is $157m^2/g$. Acidic characteristics of the catalyst are analyzed by temperature-programmed desorption of ammonia and infrared spectroscopy of adsorbed pyridine. 2-Butanol dehydration reaction was carried out in a fixed bed catalytic reactor. Yields of 1-butene, trans-2-butene, and cis-2-butene at $350^{\circ}C$ were 25.6 wt%, 19.2 wt%, and 29.9 wt%, respectively. This catalytic activity of the catalyst based on water treatment sludge in 2-butanol dehydration is due to the acid sites composed of Bronsted acid sites and Lewis acid sites. It was confirmed that the catalyst based on water treatment sludge can be utilized to produce $C_4$ olefin through butanol dehydration.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.117-123
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• 2003

In succession to the previous paper, the tritium injection system and the regeneration system of the tritium handling system are presented. Both systems should be placed inside glove boxes since there can be potential leakage of tritium from these systems. The tritium injection system should be capable of measuring the exact amount of the injected tritium to keep track of the tritium inventory. The tritium injection system is designed to recover the remaining tritium from the system after injection for the minimization of tritum release to the environment as well as for the recovery of precious resource. TRS equipment such as MS, Ni catalyst bed, and metal getter are regenerated with a standalone regeneration system. Unlike other equipments which can be regenerated by heating and purging with appropriate gas, regeneration of the metal getter used to recover tritium is somewhat complicated.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.3
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• pp.15-21
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• 2011

With petroleum reserves dwindling, interest has been increasing worldwide in Fischer-Tropsch synthesis (FT) as a method of producing synthetic liquid fuels and chemicals from coal, natural gas or biomass. In general, FT synthesis is operated through the gas phase fixed-bed reaction system. Recently, there are lots of study in supercritical fluid due to unique characteristics such as the quick diffusion of reactant gas, effective removal of reaction heat, and the in-situ extraction of high molecular weight hydrocarbon, such as wax. In this study, our major aim is to obtain a deeper insight into the effect of the type of support on the reaction performance over a supported cobalt catalyst in a fixed bed reactor.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.591-597
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• 2023

Pakistan depends heavily on imports for its fuel requirements. In this experiment, catalytic pyrolysis of a blend of feedstock's consisting of date seed, wheat straw, and corn cob was conducted in a fixed bed reactor to produce oil that can be used as an alternative fuel. The main focus was to emphasize the outcome of important variables on the produced oil. The effects of operating conditions on the yield of bio-oil were studied by changing temperature (350-500 ℃), heating rate (10, 15, 20 ℃/min), and particle size (1, 2, 3 mm). Moreover, ZnO was used as a catalyst in the process. First, the thermal degradation of the feedstock was investigated by TGA and DTG analysis at 10 ℃/min of different particle sizes of 1, 2, and 3mm from a temperature range of 0 to 1000 ℃. The optimum temperature was found to be 450 ℃ for maximum degradation, and the oil yield was indicated to be around 37%. It was deduced from the experiment that the maximum production of bio-oil was 32.21% at a temperature of 450 ℃, a particle size of 1mm, and a heating rate of 15 ℃/min. When using the catalyst under the same operating conditions, the bio-oil production increased to 41.05%. The heating value of the produced oil was 22 MJ/kg compared to low-quality biodiesel oil, which could be used as a fuel.

• Clean Technology
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• v.6 no.1
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• pp.17-25
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• 2000

Catalytic oxidation of volatile organic compounds(benzene, toluene, xylene) over transition metals/ALO-6 catalysts was investigated in a fixed bed flow reactor system at atmospheric pressure. The orders of catalytic activities for the complete oxidation of toluene were Cu>Mn>Fe>V>Mo>Co>Ni>Zn for 15% transition metals/ALO-6 catalyst system. Increasing the calcination temperature resulted in decreasing the specific surface areas of catalyst, subsequently the catalytic activity. The loading of Cu on ALO-6 had a great effect on the catalytic activity and 5% Cu/ALO-6 catalyst showed higher catalytic activity, which may be contributed to the uniformly distributed active sites. Benzene, toluene and xylene were completely oxidized to carbon dioxide over 5% Cu/ALO-6 catalyst at over $380^{\circ}C$ and 4.5 g-cat.hr./g-mole. The orders of the kinds of reactants for catalytic activity over 5% Cu/ALO-6 were toluene>xylene>benzene. As the concentration of reactant increased, the catalytic activity decreased due to self-poison of reactant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6575-6580
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• 2013

Various modified SCR catalysts were prepared and tested to improve the strength of catalysts for use under severe conditions. The SCR catalysts were modified with a binder and dispersion agent, and tested at the fixed bed reactor. FT-IR and $H_2$-TPR were used to analyze the degree of hydrogen use and ammonia adsorption by the modified catalysts. In the case of the SCR catalysts coated with 2.3g of the binder, 4.7g of ethanol, and 0.1g of dispersion agent, the strength of catalyst was increased by approximately 12%. On the other hand, despite the enhancement of strength, the activities of the SCR catalysts were decreased by 2-10%. When the mixed solution composed of binder, dispersion agent and $SiO_2$ solution was precipitated on the catalyst, the $NO_x$ conversion of the catalyst was decreased slightly. The Bronsted acid site and Lewis acid site worked as the activators for the SCR reaction, and were decreased by $SiO_2$.

• Advances in Energy Research
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• v.8 no.4
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• pp.223-231
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• 2022

An ex-situ gravitational fixed bed pyrolysis reactor was used over Al₂O₃ supported Ni₂P based catalyst with various Ni/P molar ratios (0.5-2.0) and constant nickel loading of 5.37 mmol/g Al₂O₃ to determine the hydrodeoxygenation of rubberwood sawdust (RWS) at atmospheric pressure. The 3D catalysts formed were characterized structurally as well as acidic properties were determined by hydrogen-temperature programmed reduction (TPR). The Ni₂P phase formed completely on Al₂O₃ for 1.5 Ni/P ratio, although lesser crystallite sizes of Ni₂P were seen at Ni/P ratios less than 1.5. Additionally, it was shown that when nickel loading level increased, acidity increased and specific surface area dropped, probably because nickel phosphate is not easily converted to Ni₂P. When Ni/P ratio was 1.5, Ni₂P phase fully formed on Al₂O₃. The catalytic activity was explained in terms of impacts of reaction temperature and Ni/P molar ratio. At relatively high temperature of 450℃, the high-value deoxygenated produce was predominantly composed of n-alkanes. Based on the findings, it was suggested that hydrogenolysis, hydrodeoxygenation, dehydration, decarbonylation, and hydrogenation are all part of mechanism underlying hydrotreatment of RWS. In conclusion, the synthesized Ni₂P/ Al₂O₃ catalyst was capable of deoxygenating RWS with ease at atmospheric pressure, primarily resulting in long chained (C₉-C₂₄) hydrocarbons and acetic acid.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.3
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• pp.27-33
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• 2004

The catalytic effect of waterworks sludge on NOx removal in $BaTiO_3$pellets and sludge pellets combined packed-bed plasma reactor with plate-plate electrode geometry is measured for the various conditions. NOx removal rate is about 90[%] at $BaTiO_3$-sludge combined reactor used fresh sludge. $NO_2$ and $O_3$ as byproducts are significantly generated in only $BaTiO_3$ packed-bed plasma reactor, however, in $BaTiO_3$-sludge combined packed-bed reactor, $NO_2$ and $O_3$ are completely removed while $CO_2$ as by-products are observed from FTIR spectra. $NO_2$ and $O_3$ seem to react with metallic molecules, metal oxide, and organic compounds that are generally chlorophyll included in sludge. NOx removal rate increases with $O_2$ concentration increasing. Removal rates $NO_2$ and $O_3$ are independent of operating time and repetition measurement times.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.652-659
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• 1999

The trend of poisoning of reforming catalyst along with the position of anodic catalyst bed was studied. Keeping the conditions that steam to carbon ratio was 2.5, operating voltage was 0.75 V, current density was $140mA/cm^2$, the unit cell was operated during 24 hrs at a steady state. And then the cell was stopped, the catalysts packed in the position of inlet, middle and outlet were sampled individually and then the amount of carbon, Li and K poisoned were analysed. After 100 hrs operated, the catalysts at the same positions were analysed at the same manner. The result of this experiment was as followings. After 24 hrs operated, the poisoning amounts of Li and K in the catalyst were 0.27 wt% at inlet, 0.23 wt% at middle and the highest value 1.59 wt% at outlet. After 100 hrs, the amount of poisoning is the highest in the catalyst packed at the inlet of unit cell. The performance simulation of unit cell explained these trends of poisoning catalysts. The simulation told that the catalyst in the region of the inlet of unit cell treated the 90% of initial methane flow rate and the highest electrochemical reaction happened in this region. So the catalysts of this region were the most poisoned with carbon, Li and K and also the rate of poisoning is faster than that of the catalyst at other regions. The temperature at the region of outlet of unit cell was $30^{\circ}C$ higher than that of other regions, so more Li, and K vaporized than at other regions and little reforming reaction at this region made the catalysts poisoning rate low.

• Journal of the Korean GEO-environmental Society
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• v.17 no.10
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• pp.5-11
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• 2016

In this study, the factors affecting commercialization of $Pt/TiO_2$ catalyst, which can oxidize HCHO at room temperature, was investigated. In order to determine the optimum noble metal loading, the catalytic activity was evaluated by varying the Pt loadings; the best catalytic activity was achieved for 1 wt% of Pt. In addition, the catalyst prepared under the reduction condition showed an excellent HCHO oxidation conversion at room temperature. Based on these results, it was confirmed that the activity could be changed by oxidation state of active metal, and in case of Pt, metallic Pt ($Pt^0$) species was more active on HCHO oxidation at room temperature. As a result of evaluating an effect of space velocity to determine the optimum operating condition, it was found that in the lower space velocity, conversion rate of HCHO was increased due to increase of catalyst bed. Catalytic activity was greater in the presence of moisture than in its absence. Through above results, the key factors for commercialization of oxidation catalyst, which was operated at room temperature even without any additional energy source was confirmed.