• 한국환경농학회지
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• 제27권4호
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• pp.321-327
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• 2008

본 연구는 간척지 토양 중 미사질양토에 대하여 입단형성을 위해 가해진 토양개량제가 토양 중 양이온 함량변화에 미치는 영향을 분석하기 위하여 토양개량제로 이수석고 1550 (G1), 3100 (G2), 6200 (G3) kg/10 a, 팽화왕겨 1000 (H1), 2000 (H2), 3000 (H3) kg/10 a, 팽화왕겨 1500 kg/10 a에 zeolite 200 (HZ1), 400 (HZ2), 800 (HZ3) kg/10 a가 되도록 처리량을 달리하여 3년간 연용시용하고, 버뮤다그래스를 재배한 토양을 60, 90, 120일 경과 후 채취하여 토양개량제 연용이 토양 중 양이온 함량변화에 미치는 결과를 보고한다. 이수석고의 처리는 토양 중 K, Na, Mg의 함량을 현저히 감소시키는 것으로 나타났다. K 함량은 연용 토양개량제의 종류 및 처리수준과 관계없이 년도별 감소현상이 뚜렷하여서 2004 > 2005 > 2006 순으로 낮아지는 경향을 나타내었다. 또한 각 년도별 토양 중 K 함량은 안정적 변화를 보이면서 이수석고 < 팽화왕겨 < 팽화왕겨+zeolite 순으로 토양 중 K 함량이 높았다. Na 함량은 이수석고 < 팽화왕겨 < 팽화왕겨+zeolite의 순으로 연용 토양개량제의 종류 및 처리수준과 관계없이 각 년도에서에서 높게 나타났다. 특히 팽화왕겨 및 팽화왕겨+zeolite의 각각 처리는 이수석고 처리구와는 달리 대조구의 Na 함량 보다 높아지고 있는 현상이 계화도 세사양토의 결과와 비교가 되었다. Mg 함량은 년도별 변화는 이 수석고 < 팽화왕겨+zeolite < 팽화왕겨 순으로 높아지고, 연용기간이 길수록 높아지는 경향이었다. 이수석고 연용처리는 세사양토에서 보여준 결과와 유사하게 처리수준이 높을수록 토양 중 Ca이 높아지는 결과가 되었으며, 년도별 변화도 2004 < 2005 < 2006년의 순으로 연용년수에 따라 높아졌다.

• Membrane and Water Treatment
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• 제8권5호
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• pp.437-448
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• 2017

A high quality Na-X zeolite membrane was synthesized on a seeded ${\alpha}-alumina$ disc by the secondary growth method. Structural characterization was done by X-ray spectroscopy, FT-IR spectroscopy, SEM and AFM imaging. The performance evaluation of the membrane was firstly tested in separation of glucose/water solutions by pervaporation process. There was obtained a separation factor $182.7{\pm}8.8$, while the flux through the membrane was $3.6{\pm}0.3kg\;m^{-2}\;h^{-1}$. The zeolite membrane was then used for desalination of aqueous solutions consisting of $Na^+$, $Ca^{2+}$, $Cs^+$ and $Sr^{2+}$ because of the importance of these ions in water and wastewater treatments. The effects of some parameters such as temperature and solution concentration on the desalination process were studied for investigating of diffusion/adsorption mechanism in membrane separation. Finally, high water fluxes ranged from 2 up to $9kg\;m^{-2}\;h^{-1}$ were obtained and the rejection factors were resulted more than 95% for $Na^+$ and $Ca^{2+}$ and near to 99% for $Cs^+$ and $Sr^{2+}$. Based on the results, fluxes were significantly improved due to convenient passage of water molecules from large pores of NaX, while the fouling was declining dramatically. Based on the results, NaX zeolite can efficiently use for the removal of different cations from wastewaters.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 추계학술발표회요약집
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• pp.283.1-283
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• 2001

• Bulletin of the Korean Chemical Society
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• 제20권4호
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• pp.445-450
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• 1999

Molecular dynamics (MD) simulation of non-rigid H-Y zeolite framework are performed at 298.15 and 5.0 K. Usual bond stretching, bond angle bending, torsional rotational, and non-bonded Lennard-Jones and electrostatic interactions are considered as intraframework interaction potentials. Calculated atomic parameters are in good agreement with the experiment, which indicates the successful reproduction of the framework structure and its motion. Both calculated bond lengths and bond angles are also in good agreement with the experiment except generally for a little longer bond lengths and a little smaller T-O-H bond angles. The calculated overall site occupation of HI keeps the order O(2) > O(3) > O(4) > O(t) at 298.15 K, which is very different from the experimental prediction, O(l) > O(3) > O(2) at 5 K. Calculated IR spectra of the H-Y zeolite framework show that most of the main peaks of the O-H bonds are in the broad region 3700-5000 cm-1 and that the O-T stretching bands appeared in 0-2000 cm-1 and at 2700 cm-1

• 한국환경과학회지
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• 제24권2호
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• pp.151-162
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• 2015

The adsorption characteristics of Sr ions and Cs ions in single and binary solution by zeolite A were investigated in batch experiment. The adsorption rate of Sr ions and Cs ions by zeolite A obeyed pseudo-second-order kinetic model in single and binary solution. The initial adsorption rates (h) and adsorption capacities of both ions obtained from pseudo-second-order kinetic model, and the values were decreased with increasing concentration of the competitive ions (0~1.5 mM). Also, adsorption isotherm data in binary solution were well fitted to the extended Langmuir model, the maximum adsorption capacities of Sr and Cs calculated from the model were 1.78 mmol/g and 1.64 mmol/g, respectively. The adsorption of Sr and Cs ions by zeolite A was carried out in the presence of other cations such as $Na^+$, $K^+$, $Mg^{2+}$ and $Ca^{2+}$. The results showed that the zeolite A can maintain a relatively high adsorption capacity for Sr and Cs ions and exhibits a high selectivity in the presence of competitive cations. The effect of competition had an order of $Ca^{2+}$ > $K^+$ > $Mg^{2+}$ > $Na^+$ for Sr ions and $K^+$ > $Ca^{2+}$ > $Na^+$ > $Mg^{2+}$ for Cs ions at the same cation concentration.

• 대한환경공학회지
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• 제34권8호
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• pp.517-522
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• 2012

본 연구에서는 오 폐수의 처리에 있어서 천연제올라이트 및 맥반석을 활용하여 오 폐수의 응집 및 흡착 메커니즘에 적용하여 수처리제로서의 타당성을 검토하고자 하였다. Jar test를 이용한 응집 전 후의 $COD_{Cr}$의 제거율을 평가하였다. 맥반석과 천연제올라이트를 수처리제로써 주입량을 400~1,200 g/L로 변화시켜 처리한 결과 $COD_{Cr}$ 최종제거율은 별 차이를 보이지 않았으나, 맥반석과 천연제올라이트를 $600^{\circ}C$로 소결하여서 도시하수를 처리할 경우 $COD_{Cr}$제거율이 각각 15%, 3%정도 상승하였다. 또한 맥반석과 천연제올라이트를 혼합하여 미용화장지 폐수처리에 적용하였으며, 또 다른 폐수처리제로서의 가능성을 검토하였다.

• Asian Journal of Atmospheric Environment
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• 제11권1호
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• pp.15-28
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• 2017

The adsorptive removal properties of synthetic A4 zeolite were investigated against a total of 16 offensive odors consisting of reduced sulfur compounds (RSCs), nitrogenous compounds (NCs), volatile fatty acids (VFAs), and phenols/indoles (PnI). Removal of these odors was measured using a laboratory-scale impinger-based adsorption setup containing 25 g of the zeolite bed (flow rate of $100mL\;min^{-1}$). The high est and lowest breakthrough (%) values were shown for PnIs and RSCs, respectively, and the maximum and minimum adsorption capacity (${\mu}g\;g^{-1}$) of the zeolite was observed for the RSCs (range of 0.77-3.4) and PnIs (0.06-0.104), respectively. As a result of sorptive removal by zeolite, a reduction in odor strength, measured as odor intensity (OI), was recorded from the minimum of approximately 0.7 OI units (indole [from 2.4 to 1.6]), skatole [2.2 to 1.4], and p-cresol [5.1 to 4.4]) to the maximum of approximately 4 OI units (methanethiol [11.4 to 7.5], n-valeric acid [10.4 to 6.5], i-butyric acid [7.9 to 4.4], and propionic acid [7.2 to 3.7]). Likewise, when removal was examined in terms of odor activity value (OAV), the extent of reduction was significant (i.e., 1000-fold) in the increasing order of amy acetate, i-butyric acid, phenol, propionic acid, and ammonia.

• 한국재료학회지
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• 제5권8호
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• pp.1035-1039
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• 1995

경북 감포지역에서 산출되는 천연 벤토나이트를 이용하여 제올라이트를 합성하였으며 세제용 builder로서 가능성을 연구하였다. 최적의 합성조건은 기질의 몰비가 SiO$_2$/Al$_2$O$_3$=2, $Na_2$O$_3$/Al$_2$O$_3$=1, $H_2O$/A1$_2$O$_3$=30이고 9$0^{\circ}C$에서 3시간 반응시킬 경우였고, 이 조건에서는 A형 제올라이트가 합성되는 것을 XRD를 통하여 확인하였다. 최적 조건에서 합성된 제올라이트의 이온교환능을 측정하기 위하여 경도 40$^{\circ}$Dh의 CaCl$_2$용액과 3$0^{\circ}C$에서 IS분 접촉시킨 결과 264.9mg CaO/g-zeolite 정도로 우수한 값을 나타내었다. 이 시료의 백색도는 89%이었고, 평균 입자크기는 9.95$\mu\textrm{m}$이었다.

• 방사성폐기물학회지
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• 제20권3호
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• pp.259-268
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• 2022

Molten salt consisting primarily of eutectic LiCl-KCl is currently being used in electrorefiners in the Fuel Conditioning Facility at Idaho National Laboratory. Options are currently being evaluated for storing this salt outside of the argon atmosphere hot cell. The hygroscopic nature of eutectic LiCl-KCl makes is susceptible to deliquescence in air followed by extreme corrosion of metallic cannisters. In this study, the effect of occluding the salt into a zeolite on water sorption/desorption was tested. Two zeolites were investigated: Na-Y and zeolite 4A. Na-Y was ineffective at occluding a high percentage of the salt at either 10 or 20wt% loading. Zeolite-4A was effective at occluding the salt with high efficiency at both loading levels. Weight gain in salt occluded zeolite-4A (SOZ) from water sorption at 20% relative humidity and 40℃ was 17wt% for 10% SOZ and 10wt% for 20% SOZ. In both cases, neither deliquescence nor corrosion occurred over a period of 31 days. After hydration, most of the water could be driven off by heating the hydrated salt occluded zeolite to 530℃. However, some HCl forms during dehydration due to salt hydrolysis. Over a wide range of temperatures (320-700℃) and ramp rates (5, 10, and 20℃ min^-1), HCl formation was no more than 0.6% of the Cl^- in the original salt.

• 한국환경농학회지
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• 제15권2호
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• pp.232-238
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• 1996

폐수(廢水) 중(中) 암모니아태(態) 질소(窒素)를 zeolite column을 이용(利用)하여 제거(除去)할 경우 그 제거효율(除去效率)을 높이기 위한 zeolite column의 적정조건(適正條件)을 조사(調査)하였다. 암모니아태(態) 질소(窒素) 용액(溶液)의 column 투과속도(透過速度), 유입수(流入水)의 농도(濃度) 및 분취회수(分取回數)가 증가(增加)할수록 제거효율(除去效率)은 감소(減少)하였다. Zeolite첨가량(添加量)이 증가(增加)할수록 암모니아태(態) 질소(窒素)의 제거효율(除去效率)은 증가(增加)하였으나, column의 직경(直徑)이 커질수록 그 효율(效率)은 감소(減少)하였다. 암모니아태(態) 질소(窒素)의 제거효율(除去效率)에 미치는 요인(要因)들을 다중회귀분석(多重回歸分析)한 결과(結果) zeolite의 첨가량(添加量), 투과속도(透過速度), 용액(溶液)의 첨가농도(添加濃度) 및 분취회수(分取回數)와 제거효율(除去效率) 간에는 고도(高度)의 유의성(有意性)이 인정(認定)되었으나, column의 직경(直徑)과는 유의성(有意性)이 인정(認定)되지 않았다. Column의 직경요인(直徑要因)을 제외(除外)한 변수(變數)들에 대한 회귀식(回歸式)은 암모니아태(態) 질소(窒素)의 제거효율(除去效率)(%) = $0.620\;{\times}\;zeolite$의 양(量) $-0.456\;{\times}$ 투과속도(透過速度)$-0.212{\times}$ 용액(溶液)의 첨가농도(添加濃度)$-3.038{\times}$ 분취회수(分取回數)+100.1로 나타났다. 회귀식(回歸式)에 의한 제거효율(除去效率) 리논치(理論値)와 실제 축산폐수(畜産廢水)의 투과실험결과(透過實驗結果)인 실험치(實驗値)는 거의 일치(一致)하는 것으로 나타났다.