• 제목/요약/키워드: 4A zeolite

검색결과 524건 처리시간 0.033초

Water Sorption/Desorption Characteristics of Eutectic LiCl-KCl Salt-Occluded Zeolites

  • Harward, Allison;Gardner, Levi;Oldham, Claire M. Decker;Carlson, Krista;Yoo, Tae-Sic;Fredrickson, Guy;Patterson, Michael;Simpson, Michael F.
    • 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.

천연 제올라이트/에폭시 복합재료의 경화반응 속도론 (Cure Kinetics of Natural Zeolite/Epoxy Composites)

  • 이재영;천인숙;심미자;김상욱
    • 공업화학
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    • 제7권2호
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    • pp.387-392
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    • 1996
  • 천연 제올라이트/에폭시 수지 복합재료의 경화반응 속도론을 연구하기 위해 DSC 분석법 중 승온적 방법을 이용하였다. 천연 제올라이트의 함량이 증가함에 따라 반응 시작온도와 발열피크의 온도가 낮아졌다. Diglycidyl ether of bisphenol A(DGEBA)/4,4'-methylene dianiline(MDA)/malononitrile(MN, 10phr)에 제올라이트를 20phr 충전한 경우에는 하나의 발열피크가 나타나며, 30phr인 경우에는 shoulder가 나타났다. 40phr의 제올라이트가 충전된 경우에는 발열피크가 두 개로 분리되며, 첫번째 발열피크의 활성화에너지, $Ea_1$은 12.30 kJ/mol이고, 두번째 발열피크의 활성화에너지, $Ea_2$는 12.70 kJ/mol이었다.

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생균제와 제올라이트를 혼합한 축분첨가제가 돈분 슬러리에서 발생하는 유해 가스 발생량에 미치는 영향 (Effect of Manure Additives Mixed with Probiotics and Zeolite on Harmful Gas Production Released From Pig Slurry)

  • 장우환;최인학
    • 한국환경과학회지
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    • 제31권1호
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    • pp.99-102
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    • 2022
  • The aim of this study was to investigate the effect of manure additives mixed with probiotics and zeolite on harmful gas production generated by pig slurry. A total of 180 crossbred pigs ([Yorkshire × Land race] × Duroc, live weight 70±3.21 kg) were allotted to a completely randomized design with 3 treatments and 3 replications (20 heads per replicate). The treatments consisted of 0% (control), 0.05% (T1), or 1% (T2) of manure additives mixed with probiotics and zeolite. Manure additives were added weekly to pig slurry pits (2 m × 4.5 m × 1.2 m) on a volumetric basis. For ammonia measured at both 10 cm and 90 cm above the pig slurry pit, a statistical significance (p<0.05) was found in probiotics and zeolite-treated manure additives at weeks 1 - 3, except for week 0. In addition, hydrogen sulfide levels measured at 10 cm above the pig slurry pit were not affected by the manure additive at weeks 0 and 1, but showed a significant statistical difference at weeks 2 and 3 (p<0.05). Therefore, supplementing pig slurry with 0.05% and 0.1% manure additives mixed with probiotics and zeolite was found to be effective in reducing environmental pollution in pig facilities.

실란 결합제 처리된 에폭시 수지 복합재료의 계면 특성 (Interface Characteristics of Epoxy Composite Treated with Silane Coupling Agent)

  • 이재영;이홍기;심미자;김상욱
    • 한국재료학회지
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    • 제11권12호
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    • pp.1009-1013
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    • 2001
  • The effects of coupling agent on the interface characteristics between epoxy resin and natural zeolite were studied by SEM, optical microscope and universal testing machine (UTM). Epoxy resin as a matrix was diglycidyl ether of bisphenol A (DGEBA)/4,4'-methylene dianiline (MDA)/malononitrile (MN) system and natural zeolite as an inorganic fillet was produced in Korea. With the increment of zeolite content, tensile strength decreased and it was due to the different elastic moduli of two materials. When external stress was loaded on the composites, the stress concentrated on the weakly bonded interface and crack grew easily. To improve the interface characteristics, the surface of the natural zeolite was treated with the silane coupling agent and it was found that the tensile strength was increased. The morphology of the interface showed that the bonding characteristics were modified by coupling agent.

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Structural Effects on the Tensile and Morphological Properties of Zeolite-filled Polypropylene Derivative Composites

  • Jagannath, Jagannath Biswas;Kim, Hyun;Yim, Chai-Suk;Cho, Jungh-Wan;Kim, Geon-Joong;Choe, Soon-Ja;Lee, Dai-Soo
    • Macromolecular Research
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    • 제12권5호
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    • pp.443-450
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    • 2004
  • We have studied the effects that inorganic zeolite powder have on structurally different copolymer [poly(propylene-co-ethylene)] and terpolymer [poly(propylene-co-ethylene-co-l-butene)] systems and the possibility of preparing suitable porous composite films. The impact strength and yield stress of the composites did not improve upon any further loading of zeolite, but the modulus increased gradually with respect to the filler loading. The experimental modulus of each of the two systems was compared with theoretical models. We performed a morphological study of the filler mixing efficiency and image analysis. The number-, weight-, and z-average air hole diameters were compared with respect to the draw ratio as well as the zeolite loading. The experimental results suggest that these two matrices can provide a new choice for preparing future multiphase polymeric porous films by stretching them unidirectionally. In particular, we suggest that a 40 wt% zeolite loading at a draw ratio of 4 is useful for porous film applications.

PET와 이온교환 Zeolite 나노 복합 방적사로 제조한 니트의 항균성 (Antimicrobial Properties of Knit made with PET and Ion Exchange Zeolite Nanocomposite Spun Yarn)

  • 전용욱;박영미
    • 한국염색가공학회지
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    • 제33권1호
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    • pp.24-30
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    • 2021
  • In this study, PET containing 3% silver ion-exchange zeolite was mixed with cotton in a ratio of 6:4 to prepare a spun yarn to evaluate the tensile strength, absorption speed, absorption rate, antibacterial property, and the efficiency of deodorization. As a result, the following conclusions were obtained. First, it can be confirmed that silver ion exchange zeolite is evenly distributed inside and on the surface of the antimicrobial PET-SF through SEM. It was found that the tensile strength between the CVC sample mixed with silver ion zeolite PET and cotton and the normal cotton 100% sample was slightly lower in the CVC sample. Although the absorption speed and water absorption rate were measured to find out the moisture characteristics, it was confirmed that there was no significant difference. The contact angle was slightly larger in the antimicrobial CVC sample, but the time it took for the moisture to completely penetrate into the knit fabric was 0.85 seconds. In addition, it was found that out of the total mixing ratio, 40% of antibacterial PET was spun with regular cotton to produce yarn, which had an excellent bacteria reduction rate of 99.9% and a deodorization efficiency of 85%.

Nitrate Reduction without Ammonium Release using Fe-loaded Zeolite

  • Lee Seunghak;Lee Kwanghun;Lee Sungsu;Park Junboum
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제10권1호
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    • pp.1-5
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    • 2005
  • 영가 철을 이용한 질산성 질소 환원에 대한 연구는 지금까지 활발히 진행되어 왔지만, 이 반응에서 생성된 암모늄 부산물에 대한 적절한 처리과정은 아직 보고되지 않았다. 하지만, 암모늄은 먹는 물 수질기준에 의해 지하수 오염물로 분류되고 있어 (허용치 0.5 mg-N/L), 질산성 질소로 오염된 지하수 정화에 영가 철을 단독으로 사용하는 것에는 한계가 있다. 따라서, 본 연구의 목적은 질산성 질소를 환원함과 동시에 이 과정에서 발생하는 암모늄을 제거할 수 있는 반응물질을 개발하는데 있다. 본 연구에 사용한 Fe-loaded zeolite는, 제올라이트와 Fe(II) 용액을 교반시켜 제올라이트 구조 안으로 Fe(II)를 흡착유도하고, 이를 sodium borohydride로 환원하는 과정을 통해 제작되었다. Fe-loaded zeolite 제작에 사용된 Fe(II) 용액의 농도를 실험을 통해 산정하고, 이를 통해 Fe-loaded zeolite를 제작한 후, Fe-loaded zeolite의 질산성 질소 제거 성능을 확인하기 위해 두 가지 pH조건에서 회분식 실험을 수행하였다. 80시간의 반응을 통해 Fe-loaded zeolite는 초기 pH가 3.3인 경우 약 $60\%$의 질산성 질소를, pH가 6인 경우는 약 $40\%$의 질산성 질소를 제거하였고, 암모늄 부산물은 전혀 검출되지 않았다. 영가 철의 경우, 각 초기 pH조건에서 Fe-loaded zeolite보다 뛰어난 질산성 질소 제거성능을 보였지만, 반응 후 상당량의 암모늄 부산물을 생성하였다. 질산성 질소와 암모늄을 포함한 질소(-N)제거 효능의 관점에서 Fe-loaded zeolite의 경우 pH 3.3과 6의 경우에서 각각 $60\%$$40\%$의 제거효율을 보인 반면, 영가 철의 제거효율은 무시할만한 수준으로 나타났다.

무기계 혼화재료를 혼입한 모르타르 시편의 광촉매 처리를 고려한 NOx 저감 성능 (NOx Reduction Performance in Cement Mortar with TiO2 Treatment and Mineral Admixture)

  • 윤용식;김혁중;박장현;권성준
    • 한국건설순환자원학회논문집
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    • 제8권4호
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    • pp.506-513
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    • 2020
  • 본 연구에서는 무기계 혼화재료인 제올라이트 및 활성 황토를 혼입한 모르타르의 역학적 특성, 흡수율, NOx 저감 성능을 평가하였다. 제올라이트 및 활성 황토는 결합재로서 시멘트의 대체재로 사용되었으며 치환율은 각 20, 30%로 설정하였다. 각 배합의 압축강도 및 휨강도를 평가한 결과, Plain 배합에서 가장 높은 강도가 평가되었다. 제올라이트 및 활성 황토의 혼입율이 증가할수록 강도가 낮아지는 경향이 나타났다. 또한 활성 황토와 제올라이트 혼입 배합간의 강도 차이는 미미한 수준으로 나타났다. 흡수율을 평가하기 위해 기존의 배합의 물-결합재 비를 낮추고 활성 황토 및 제올라이트의 치환률을 25%로 설정한 배합을 설계하였다. 제올라이트 혼입 배합에서 가장 높은 흡수율이 평가되었으며, 나머지 두 배합 간에 흡수율의 차이는 매우 적었다. 광촉매 코팅의 유무를 고려한 NOx 저감 성능을 평가한 결과, 동일 배합이라 하더라도 광촉매를 코팅함에 따라 뚜렷한 NOx 농도 저감이 나타났다. 또한 제올라이트 및 활성 황토는 다공성 성질을 갖기 때문에 Plain 배합 보다 높은 NOx 감소 성능을 나타내었다. 활성 황토 배합의 경우 흡수율은 제올라이트 배합보다 낮은 값을 나타내었지만, 제올라이트 혼입 배합보다 뛰어난 NOx 저감 성능이 나타났다.

중석광 폐재광미의 매립지에서 나오는 침출수 중의 중금속 제거 (Heavy matal removal in leaching water from the region buried tungsten tailing)

  • 이동훈;오세강;최충렬;박만;최정
    • 한국환경농학회지
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    • 제19권3호
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    • pp.218-222
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    • 2000
  • 중석광의 광미를 매립한 토양에서 유출되는 침출수에 의한 환경영향을 알아보기 의하여 시기별로 용출수를 분석하고 및 zeolite column실험을 통하여 용출수 중의 zeolite를 이용하여 중금속 제거 가능성을 조사하였다. 폐재댐 침출수는 As $1.21{\sim}1.54ppm$, Pb $0.11{\sim}0.15ppm$, $SO_4\;^{2-}\;302{\sim}378ppm$으로 건설된지 수년이 지난 지금까지도 수질을 오염시키는 정도의 중금속이 침출되고 있다. 탈이온수 및 인공산성비 (pH3, pH4)를 광미를 충진시킨 칼럼을 통과시켰을 때 pH 4의 용액에 의하여 용출되는 Mn, Na, Ca량이 탈이온수에 의한 용출보다 $1{\sim}8%$정도 증가되었으나, W, Mo은 pH가 높을수록 용출량이 많았다. Zeolite에 의한 용출수 중 중금속 제거효과는 중금속의 종류에 따라 약간씩 다르게 나타났지만 zeolite를 통과한 용액에서 낮은 농도의 중금속이 검출 되어, zeolite에 의한 폐재댐의 중금속 제거가 효과가 높은 것으로 판단되었다.

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Synthesis and Characterization of Selenium-sorbed Ca2+-exchanged Zeolite A for High-performance Feed

  • Seo, Sung Man;Lee, Sang Gull;Kim, Hu Sik;Lee, Ha Young;Lim, Woo Taik
    • 한국토양비료학회지
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    • 제47권4호
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    • pp.306-312
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    • 2014
  • This study was carried out to develop high-performance feed using selenium-sorbed $Ca^{2+}$-exchanged zeolite A. The contents of Se increased with increasing reaction temperature and the content of $Ca^{2+}$ ions in $Ca^{2+}$-exchanged zeolite A. A synthesized high-performance feed (0.306 ppm) was applied to poultry farming for 4 and 7 weeks, respectively. Se contents in chicken meats and eggs were 18.8, 27.2, and 94.1 ppb and 73.7, 14.9, and 64.5 ppb for control (retail chicken meats), 4, and 7 weeks, respectively; Ca contents were 3.8, 9.9, and 11.9 ppm and 48.6, 48.3, and 53.6 ppm, respectively. In conclusion, Se and Ca contents in chicken meats increased as feeding periods increased, but significant differences were not observed in the eggs.