• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.13 no.3_4
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• pp.89-95
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• 2007

Functional packaging paper containing botanical antimicrobial agent (BAAG) and inorganic zeolite was developed for antimicrobial activity and adsorption of ethylene gas of the paper. The physical properties of the packaging paper showed different characteristics with addition of BAAG and functional fillers: both tensile strength and burst strength were decreased, but both stiffness and tear strength were slightly increased. Zeolite also contributed to fast removal of ethylene gas known as aging hormone of fruits and vegetables. Alkyl ketene dimer (AKD) was greatly effective to endow the packaging paper with water repellency property.

• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.273-278
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• 2007

The honeycomb adsorbents and adsorption process for carbon dioxide removal from fuel gas were investigated. Zeolite paper was made with Na-X zeolite powder and ceramic fiber as raw materials. $Li^+$, $Ca^{2+}$ or $K^+$ ion exchanges for Na-X zeolite and additional Na-X coating were performed on zeolite paper for increasing the carbon dioxide adsorption capacity, after that the adsorption characteristics of the samples were analyzed. Among the ion exchanged samples, $Li^+$ ion exchanged zeolite paper was most promising but its carbon dioxide adsorption capacity was less than expected for process application. However, additional Na-X coating was found to be an effective method for increasing the carbon dioxide adsorption capacity of the zeolite paper for process application. The carbon dioxide breakthrough test of the honeycomb adsorbent prepared with the zeolite paper was studied, and fuel gas treatment capacity was calculated when the honeycomb adsorbent was used in the rotary adsorption process.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.323-327
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• 2011

A zeolite sheet (ceramic paper containing zeolite) made in a cylindrical configuration can be applied to a honeycomb rotor for the effective VOC removal. In this study, the zeolite sheet containing ZSM-5 was used as a support for Pt-loading, and its catalytic activity for the toluene combustion reaction was compared with those of the other Pt catalysts loaded on ${\gamma}-Al_2O_3$ and cordierite honeycomb. Pt/zeolite sheet catalyst showed a higher activity for toluene combustion reaction than that of $Pt/{\gamma}-Al_2O_3$ or Pt/cordierite honeycomb. On the other hand, the dispersion of Pt particles loaded on the zeolite sheet was improved by the pretreatment with $NH_3-H_2O$ vapor at room temperature. Consequently, the pretreatment of Pt/zeolite sheet by $NH_3-H_2O$ vapor significantly enhanced the catalytic activation for toluene combustion reaction.

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.691-695
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• 2005

Zeolite membranes on various supports such as filter paper, cotton fiber, and glass fiber filter were prepared by secondary growth hydrothermal synthesis. First, zeolite NaA (${\approx}0.5{\mu}m$) and silicalite-1 (${\approx}0.2{\mu}m$) crystals were synthesized as zeolite seed crystals, and they were attached to the surfaces of the supports via chemical bonding. Zeolite NaA or silicalite-1 membranes could be synthesized on the supports coated with the seed crystals. The prepared zeolite membranes were observed by scanning electron microscope and analyzed by X-ray diffraction.

• Bulletin of the Korean Chemical Society
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• v.19 no.4
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• pp.422-428
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• 1998

In the present paper, we report a molecular dynamics (MD) simulation of non-rigid zeolite-A framework only as the base case for a consistent study of the role of intraframework interaction on several zeolite-A systems using the same technique in our previous studies of rigid zeolite-A frameworks. Usual bond stretching, bond angle bending, torsional rotational, and non-bonded Lennard-Jones and electrostatic interactions are considered as intraframework interaction potentials. The comparison of experimental and calculated structural parameters confirms the validity of our MD simulation for zeolite-A framework. The radial distribution functions of non-rigid zeolite-A framework atoms characterize the vibrational motion of the framework atoms. Mean square displacements are all periodic with a short period of 0.08 ps and a slow change in the amplitude of the vibration with a long period of 0.53 ps. The displacement auto-correlation (DAC) and neighbor-correlation (DNC) functions describe the up-and-down motion of the framework atoms from the center of α-cage and the back-and-forth motion on each ring window from the center of each window. The DAC and DNC functions of the framework atoms from the center of α-cage at the 8-ring windows have the same period of the up-and-down motion, but those functions from the center of 8-ring window at the 8-ring windows are of different periods of the back-and-forth motion.

• Bulletin of the Korean Chemical Society
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• v.20 no.3
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• pp.285-290
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• 1999

In the present paper, we report a molecular dynamics (MD) simulation study for the structure and dynamics of H+ ions in non-rigid dehydrated H12-A zeolite framework at 298.15 K, using the same method we used in our previous studies of rigid and non-rigid zeolite-A frameworks. It is found that two different structures appear, depending on the choice of the Lennard-Jones parameter (σ) for the H+ ion, as is also observed in the study of rigid dehydrated H12-A zeolite framework, but the ranges of σ are different for the two structures. It is also found that some of the H+ ions exchanged their sites without changing the number of H+ ions at each site. The agreement between experimental and calculated structural parameters for non-rigid dehydrated H12-A zeolite is generally quite good. The calculated IR spectrum by Fourier transform of the total dipole moment auto-correlation function shows two major peaks, one around 2700 cm-1 and the other around 7000 cm-1. The former appears in the calculated IR spectra of non-rigid zeolite-A framework only system and the latter remains unexplained except, perhaps, as an indication of a new formation of a vibrational mode of the framework due to the adsorption of the H+ ions.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.5
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• pp.307-311
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• 2013

Direct Air Capture (DAC) technology using reusable energy is a plausible process to capture $CO_2$ from non-point sources. In this paper, adsorption and desorption were repeatedly tested using low concentration $CO_2$. Three types of adsorbents were examined in cyclic $CO_2$ adsorption and thermal regeneration. Adsorption capacities of zeolite 5A, zeolite 13X and activated carbon were 21 mg/g, 12 mg/g and 6 mg/g, respectively. Zeolite 5A shows the highest adsorption capacities after cyclic thermal regeneration.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.1
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• pp.135-141
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• 2014

$NH_3$-SCR has high NOx removal efficiency approximately 80~90%. Recently, the copper or iron ion-exchanged zeolite catalysts are widely used as automobile SCR catalysts. In this paper, the effect of the space velocity, temperature of reaction and $NO_2$ addition on the $NH_3$-SCR reaction were studied using various zeolite SCR catalysts. The test was conducted with small sized fresh catalysts in a laboratory fixed-bed flow reactor system using simulated gases. It is found that the activity of the BEA is better than MFI. It seems that three-dimensional framework and a wide pore entrance of BEA enhances the SCR activity. It is also found that low temperature activity of Cu-zeolites was better than Fe-zeolites. Once $NO_2$ was added, the NOx conversion activity of the Cu-zeolite was slightly enhanced, whereas remarkable improvement was achieved by Fe-zeolite.

• The Journal of Natural Sciences
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• v.5 no.1
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• pp.67-75
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• 1992

In the our country, especially in Yeongil and Wolsung area, abundant authigenic zeolites are found from the tuffaceous sediments and volcanic rocks of Miocene age showing wide variation in their mineralogy and abundance from horizon to horizon. The principal zeolite species identified are clinopti-lolite. mordenite. heulandite. ferrierite, and erionite. etc. Zeolite minerals are widely used in many countries in the following applications; (a) in air separation adsorption processes; (b)as desiccants; (c)in inorganic building materials; (d)in papermaking; (e)in fertilizers; (f)as soilconditioners-this application is based upon the ability of the zeolite to ion exchange with soil nutrients; (g)in the treatment of radioactive wastes; and (h)as adsorbents for toxic gases, etc. In the present paper, using natural zeolite mordenite treated with IN hydrochloric acid or IN sodium chloride solution as column packings, separation characteristics of argon, nitrogen, carbon monoxide, and methane gases have been studied by gas chromatography. By the use of mordenite treated with hydrochloric acid solution, the tailing peak of methane showed from untreated mordenite was satisfactorily reduced, although it was difficult to separate it from carbon monoxide with a column activated at $300^{\circ}C$. Using a column activated at $350^{\circ}C$, methane could be separated from carbon monoxide easily but only carbon monoxide eluted as a bad defined peak. Mordenite treated with sodium chloride solution was generally similar to chromatograms obtained by using the untreated mordenite. Both the above chemical treatments of mordenite had little effect on the separations of argon and nitrogen. The separations and the HETP values obtained from natural zeolite mordenite treated with continuously hydrochloric acid and sodium chloride solutions were almost identical with those obtained with synthetic molecular sieve 5A zeolite. On the other hand, the efficiency of column was good in the range 20~3Oml/min of the carrier helium gas rate.

• Journal of the Korean Ceramic Society
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• v.42 no.10 s.281
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• pp.654-659
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• 2005

The ceramic paper, which could adsorb VOC's effectively, was made by paper-making method with zeolite and ceramic fiber as main constituents. By this experiment, the optimal composition of the slurry for the ceramic paper formation was established. SEM observation showed that zeolite powder was uniformly dispersed and adhered to the paper by applying inorganic binder. The two type zeolites content in the ceramic paper was 26 wt$\%$ and its BET surface area was 131 $m^{2}$/g. The thickness and the basis weight of the ceramic paper were 0.2 mm and 130 g/$m^{2}$ respectively, and it had sufficient tensile characteristics to withstand tensile stress without tearing during corrugation. The total inorganic content of the paper was 78 wt$ \% $ and organic content was 22 wt$\%$. The equilibrium loading amount of toluene at the toluene at the toluene partial pressure of 0.2 mmHg was 3.2 wt$\%$.