• Journal of the Korean Chemical Society
• /
• v.32 no.5
• /
• pp.452-457
• /
• 1988

Capacity factors (k') of some inorganic anions including $BF_4^{-1}$ were measured on cetylpyridinium coated column, and with dynamic system using tetrabutylammonium salicylate on PRP-1 reversed-phase column, respectively. After optimum separation condition was obtained this method was applied to the determination of boron in some different type samples.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2012.05a
• /
• pp.216-217
• /
• 2012

QM/MM 혼성 이론 방법인 ONIOM 계산을 통해, $CO_2$가 $B_N$-BNNT 벽면에서의 흡착 반응과 $H_2CO_3$로의 전환 반응 메커니즘을 규명함으로써 $B_N$-BNNT가 효과적인 $CO_2$ 흡착제와 $H_2CO_3$ 생성 반응 촉매로 개발 가능함을 확인하였다.

• Journal of the Korean Chemical Society
• /
• v.33 no.4
• /
• pp.379-387
• /
• 1989

The synthesis of borosilicate consisted of boron and silicon was stadied. The composition, acidity and adsorption characteristics of synthesized borosilicate were examined. The synthesis rate increased with temperature and concentration of $Na_2O$, but the enhansing effects were different according to the reaction conditons. The synthesis process could be simulated by solution transfer mechanism assuming that crystals grow on the surface of crystal or nuclei with dissolved reactant. Adsorption characteristics of synthesized borosilicate was discussed with temperature programmed desorption patterns of ammonia and propylene and adsorption isotherms of propylene and propane.

• Korean Chemical Engineering Research
• /
• v.49 no.6
• /
• pp.739-744
• /
• 2011

Activated carbon SCR(CSCR) catalyst that is used to remove $NO_x$ in exhaust gas including boron discharged from the production process of liquid crystal display(LCD) shows deactivation when boron is deposited to block the pores within the catalyst or to cover its active sites. The spent carbon catalyst is regenerated by washing with various surfactants, drying and calcination. For comparison of the physical and chemical properties before and after the regeneration with the variables, type of surfactants and calcination condition, element analysis by ICP, $N_{2}$ adsorption were conducted. $DeNO_{x}$ in SCR with $NH_3$ was carried out in a fixed bed reactor at $120^{\circ}C$. The activated carbon catalyst regenerated through washing with a non-ionic surfactant in $H_{2}O$ at $90^{\circ}C$ and calcination under $N_{2}$ gas at $550^{\circ}C$ shows similar level of surface area and $NO_x$ removal efficiency with those of fresh catalyst.

• Journal of the Mineralogical Society of Korea
• /
• v.29 no.3
• /
• pp.103-111
• /
• 2016

Li-bearing hectorite, one member of trioctahedral smectite, occurred large in quantity and confirmed in Turkey western sedimentary boron deposit. Li-bearing hectorite attracted a particular attention because it is one of potential lithium resources. There have been no consensus for the change of hectorite due to heat and acid treatment although it is very important to use in industrial application. In this study, we examined changes of hectorite after heat and acid treatment as well as acid treatement followed by heating. We used clay ores collected in Bigadic deposit, which contained the highest $Li_2O$ content in Turkey boron deposits. Hectorite showed a strong endothermic reaction at $84^{\circ}C$ due to dehydration of absorbed water and interlayer water and a weak endothermic reaction above $600^{\circ}C$ owing to dehydration of crystallization water. The first endothermic reaction accompanied a large weight loss about 6%. Hectorite decomposed into enstatite, cristobalite and amorphous Fe material at $762^{\circ}C$ with exothermic reaction. When hectorite reacted with 3 kinds of 0.1 M acid during 1 hours, it had a good dissolution efficiency with $H_2SO_4{\geq}HCl$ > $HNO_3$ in order.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.08a
• /
• pp.194-194
• /
• 2011

지구상에서 화석 연료에 기초한 에너지가 고갈되어 가고 있는 지금, 여러 가지 대체 에너지들이 주목 받고 있는데 그 중에서도 수소는 친환경적 에너지원으로서 최근 많은 연구가 진행중이다. 여러 가지 저 분자 중에서 보레인은 수소 질량비가 큰 물질 중의 하나로서 이를 이용하면 적은 무게에 비하여 다른 유사한 질량의 분자들 보다 많은 수소를 발생할 수 있다. 그래서 우리는 이에 착안하여 촉매를 이용한 수소 발생 실험을 구상하게 되었다. Ru과 Co를 수산화인회석에 도입하여 우리는 이종상 촉매인 Ru-HAP와 Co-HAP를 만들었다. 이를 TEM을 이용하여 시료상의 이온교환 전후의 상을 관찰 하였고 SEM을 이용하여 촉매 표면 상의 붕소유리를 관찰 하였다. 높은 온도와 압력일수록 HAP에 더 많이 표면에 Ru과 Co가 흡착됨을 ICP를 통해서 알 수 있었다.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1998.10a
• /
• pp.156-158
• /
• 1998

원자력 발전소에서 사용하는 1차 냉각수에 대해 살펴보면, 일차냉각수의 pH는 5~8 범위이며, 수질기준은 염소이온과 불소이온이 0.15 ppm, 현탁고형물 이 0.2 ppm이나 실제 농도는 기준치보다 훨씬 낮은 매우 순수한 상태로 유지된다. 다만, 핵분열 반응도를 제어하기 위해 주입되는 붕소가 수백 ppm정도, pH를 조절하기 위해 부가되는 리튬의 1 ppm정도 포함되며, 그밖에 1ppm 정도의 실리카가 포함될 수 있다. 붕산으로 포화 운전되는 이온교환 수지탑 내에서는 붕산보다 이온선택도가 낮은 실리카는 이온교환수지에 흡착되지 않기 때문에 발전소의 가동년수의 증가에 ㄷ아라 원자로 냉각제의 실리카 농도는 점차 증가하게 되었다.

• Journal of the Korean Chemical Society
• /
• v.51 no.2
• /
• pp.178-185
• /
• 2007

Intermediate pentasil borosilicate zeolite-like materials have been crystallized by a novel method named steam-assisted conversion, which involves vapor-phase transport of water. Indeed, amorphous powders obtained by drying Na2O.SiO2.B2O3.TBA2O gels of various compositions using different boron sources are transformed into crystalline borosilicate zeolite belonging to pentasil family structure by contact with vapors of water under hydrothermal conditions. Using a variant of this method, a new material which has an intermediate structure of MFI/MEL in the ratio 90:10 was crystallized. The results show that steam and sufficiently high pH in the reacting hydrous solid are necessary for the crystallization to proceed. Characterization of the products shows some specific structural aspects which may have its unique catalytic properties. X-ray diffraction patterns of these microporous crystalline borosilicates are subjected to investigation, then, it is shown that the product structure has good crystallinity and is interpreted in terms of regular stacking of pentasil layers correlated by inversion centers (MFI structure) but interrupted by faults consisting of mirror-related layers (MEL structure). The products are also characterized by nitrogen adsorption at 77 K that shows higher microporous volume (0.160 cc/g) than that of pure MFI phase (0.119 cc/g). The obtained materials revealed high surface area (~600 m2/g). The infrared spectrum reveals the presence of an absorption band at 900.75 cm-1 indicating the incorporation of boron in tetrahedral sites in the silicate matrix of the crystalline phase.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.3 no.1
• /
• pp.49-56
• /
• 2005

Many different kinds of radwastes are discharged from the nuclear power plants, and $^{129}$I is included in these radwastes. Recovery test of $^{129}$I was evaluated for different radwastes(dry active waste, sludge, spent resin and simulated evaporator bottom). Recovery of $^{129}$I for dry active waste by acid leaching with $1.8\%$ NaClO was $74.3\%$$(RSD,\;2.2\%)$ and l291 for spent rein by alkali fusion method with KOH as a flux agent was $87.7\%$$(RSD,\;0.9\%$), respectively. iodide in simulated evaporator bottom containing a high concentration of borate was adsorbed with anion exchange resin at pH 7 phosphate buffer solution. Recovery of $^{129}$I for anion exchange resin was $92.5\%$ and not affected up to 1,200 $\mu$g/mL $H_3BO)3$(as a Boron). Recovery of $^{129}$I for the spent resin from nuclear power plant was $87.2\%$ $(RSD,\;1.2\%)$.

• Journal of Korean Society of Environmental Engineers
• /
• v.39 no.5
• /
• pp.237-245
• /
• 2017

This study was aimed at investigating effluent water quality and proposing reuse possibilities for 12 sewage treatment plants discharged more than $5,000m^3/day$ in order to recycle the sewage treatment plant effluent of Jeollabuk-do effectively. Additionally, a laboratory scale test for reprocessing water discharge was performed. Categories of reclaimed sewage water reuse were divided into 7 topics and analyzed a total of 28 items including 16 heavy metals based on water quality standard. As a results, color, BOD, TN, chloride and Electrical Conductivity (EC) exceeded reused water quality standard. In particular, color and TN exceeded in 8 and 5 sewage treatment plants, respectively. The value of chloride and EC were high in sewage treatment plants including the food and industrial wastewater. At 4 sewage treatment plants were possible to reuse without re-treatment. The laboratory scale test was conducted to SandFilter (SF)-Granular Activated Carbon (GAC)-MicroFiltraion (MF)-Reverse Osmosis (RO). Both the removal efficiencies and economic feasibility of total E. coli., color and Suspended Solid (SS) suited in case using the SF-GAC treatment method. The removal of chloride and EC had little effect in the case of SF-GAC-MF system, but RO showed over 90% of removal efficiency. After using SF-GAC process only, the concentration of $UV_{254}$ decreased sharply from 0.3651 /cm to 0.0306 /cm and it showed over 92% of removal efficiency rate. In conclusion, for the effective reuse of sewage discharged water, water quality and the surrounding terrain of treatment plants should be all taken into account. If it needed for the reprocessing, both the selection for treatment and economic combination treatment methods will have to be considered.